TWI250550B - Plasma processing method and plasma processor - Google Patents

Abstract

A plasma processing system comprises a pair of electrodes (12, 13) arranged in parallel to each other in a processing vessel (11), and a focus ring (17) arranged on one (12) of the electrodes for holding an object to be processed (8) and surrounding the object on the electrode (12). A plasma processing method for processing the object with the plasma, applying a high frequency power to the electrodes of the system to generate the plasma between the pair of electrodes, is carried out as follows. First, a focus ring having a certain material, dimension and shape is used for carrying out the plasma processing on certain processing conditions. Then, on the basis of the results of this plasma processing, if the processing rate on the outer peripheral region of the object is lower (higher) than the processing rate on the central region thereof, a new focus ring having at least one of changed material, dimension and shape is prepared so as to increase (decrease) impedance and/or relative dielectric constant of the focus ring. Then, the prepared new focus ring is used for carrying out another plasma processing on the same processing conditions.

Description

1250550 A7 B7 Ministry of Economic Affairs Intellectual Property Office Employees Consumption Cooperatives Printing 5, Invention Description (1) (Technical Field) The present invention relates to a plasma processing apparatus having a pair of electrodes arranged in parallel with each other, and using the same A plasma processing method, particularly relates to an improvement for improving the uniformity of plasma treatment for a treated object. (Background Art) A conventional plasma processing apparatus includes a lower electrode 1 that is vertically disposed in a processing container (not shown) as shown in Fig. 15, and which is opposed to the lower electrode 1 and parallel to each other The upper electrode 2 is disposed. For the electrodes 1 and 2, high-frequency power having different frequencies is applied from the first and second high-frequency power sources 3 and 4 via the matching units 3 A and 3 B. Thereby, plasma is generated between the electrodes 1 and 2, and the tantalum oxide film on the surface of the wafer 8 of the object to be processed can be etched. Further, a focus ring 5 surrounding the wafer 8 is disposed on the outer peripheral portion of the upper surface of the lower electrode 1. The focus ring 5 is used to focus the plasma between the electrodes 1 and 2 on the wafer 8. Further, a shadow ring 6 as described below is attached to the outer peripheral side of the upper electrode 2. However, in the case of the conventional plasma processing apparatus, an electric field is formed between the lower electrode 1 and the upper electrode 2 at the time of plasma treatment such as etching. However, in the lower electrode 1, the portion of the wafer and the portion of the focus ring 5 are electrically discontinuously placed, and the circuits of the high-frequency power sources 3, 4 are not formed in an equal manner. Thus, by the influence of the focus ring 5, the phase difference of the electric field strength is generated between the outer peripheral side and the center side of the wafer 8. Therefore, the etching rate of the outer periphery of the wafer 8 is relatively lowered, and the etching ratio becomes uneven (please read the back sheet of the precautions and then fill in the page); loading and setting 4 paper scales are applicable to the Chinese national standard ( CNS ) A4 Specification (210X297 公董) -4 - 1250550 A7 B7 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed

V. Description of the invention (2). Therefore, various countermeasures have been proposed to prevent the disorder of the electric field of the lower electrode. For example, Japanese Laid-Open Patent Publication No. Hei 6-166-119 discloses a semiconductor manufacturing apparatus in which a peripheral ring for varying the density distribution of reactive ions is provided around the lower electrode. Further, in Japanese Patent Application Laid-Open No. Sho. No. Sho. No. Sho. No. Sho. No. 6 2 297 197, a dry etching apparatus for providing a ring-assisted plate which can adjust the height around the outer periphery of the wafer is proposed. Further, in Japanese Patent Application Laid-Open No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. Plasma treatment method of the same potential. However, by such countermeasures, the uniformity of the electric field strength can be improved, and the uniformity of ±10% can be achieved with all efforts. Therefore, the phase difference between the electric field strengths between the outer peripheral side and the center side of the wafer 8 due to the influence of the focus ring 5 cannot be sufficiently solved. That is, there is still a problem that the etching rate becomes uneven on the outer peripheral side and the center side of the wafer 8. Hereinafter, although not shown in Fig. 15, the lower electrode 2 has an electrode material and a support body for supporting the electrode material. At this time, the electrode material is spirally formed on the support by a spiral made of stainless steel or the like. The shield ring 6 protects the spirals from the plasma, and is coupled to the focus ring 5 to be mounted on the upper electrode 2 in order to focus the plasma on the wafer 8. The shadow ring 6 is formed of an insulating material made of an inorganic oxide such as quartz, which is not contaminated during the etching process. However, in the case of plasma treatment of the shadow ring 6 formed of quartz, for example, the following problems are known. That is, use fluorocarbon gas (CXFX (please read the note on the back and fill out this page). Packing - set 4 paper size for Chinese National Standard (CNS) A4 specification (2i〇x 297 public) -5 - 1250550 A7 B7 V. INSTRUCTIONS (3) (Please read the note on the back and fill out this page)). After the oxide film on the wafer 8 is etched through the photoresist film, it is suitable for the etching process. As shown in Fig. 6, the uranium engraving rate of the photoresist film is higher on the outer peripheral side than the center side of the wafer 8, and it is understood that the uranium engraving rate of the photoresist film becomes uneven. At this time, as shown in Fig. 16, the interval between the electrodes 1 and 2 was changed in three stages from 21 mm to 35 mm, and the etching of the photoresist film at each of the intervals was measured. As a result, in any case, the etching ratio sharply rises on the outer peripheral side of the wafer 8, so that the etching rate of the photoresist film becomes uneven. As described above, when the uranium engraving rate of the photoresist film becomes uneven, it becomes a result of the uranium engraving of the tantalum oxide film, and the shape is deviated as a target. Hereinafter, as another conventional plasma processing apparatus, it is known that a magnetic field introduced into a processing space by rotation can obtain a uniformity of plasma density and uniformity of self-biasing. In this device, the plasma can be homogenized on the virtual scale, but the mechanism for rotating the magnetic field is required, so that miniaturization of the plasma device becomes a problem. Printed by the Consumers' Cooperatives of the Intellectual Property Office of the Ministry of Economic Affairs In recent years, a plasma processing apparatus has been proposed which can be miniaturized without requiring a rotating magnetic field to homogenize the plasma. As shown in Fig. 17, the device is provided with an upper electrode 2 2 具 having a conductive upper ring electrode 2 2 4 . Forming a rotating iron disposed around the processing container enables a parallel and uniform magnetic field to occur on the processed surface of the wafer while at the feeding point of the four poles of the magnetic field corresponding to the upper ring electrode 2 24 [North (N) Side 2 3 1 , south (S) side 2 3 2 , east (E) side 2 3 3, west (W) side 2 3 4 of each power supply contact], respectively, for example, a high frequency of 10 〇Μ Η z The voltage 俾 can generate an electric field. That is, near the bottom of the upper ring electrode 2 2 4, the Chinese National Standard (CNS) Α4 specification (210X 297 mm) -6- 1250550 A7 B7 is applied to the paper scale. 5. Inventive Note (4) and on the wafer The drift of the plasma between W and E can be obtained by shifting from the W side to the E side in the opposite direction of the EXB drift direction. (Please read the precautions on the back and fill out this page.) However, in the plasma processing apparatus, the horizontal magnetic field formed by the magnets disposed around the processing container is relatively high in the magnetic field density on the E side, and on the W side. Will be relatively low. Therefore, the E X B drift effect of electrons from the W side toward the E side near the lower side of the upper ring electrode 2 2 4 is lowered. SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems. First, the first item provides a difference in electric field strength between the outer peripheral side and the center side of the object to be processed which is caused by the influence of the focus ring. The plasma processing method for the plasma treatment of the object to be processed can be performed uniformly. The present inventors have found various results of the review of the plasma processing conditions, and found that the outer circumference side and the center side of the object to be processed can be reduced by making the focus ring with a specific material or size and shape depending on the processing conditions. The phase difference of the electric field strength. The invention is based on the above findings and provides a plasma processing method in which a pair of electrodes disposed in parallel with each other in a processing container are held on the electrodes of either side. In the plasma processing apparatus in which the electrode is provided with a focus ring surrounding the object to be processed, at least one of the electrodes is applied with high frequency power, and plasma is generated between the pair of electrodes by the electric power. A plasma processing method for treating a processed object, characterized in that: (a) a process of performing plasma treatment under a certain processing condition using the above-mentioned focus ring of a certain material, size and shape, and the paper scale is applicable to China National Standard (CNS) A4 Specification (210X297 mm) 1250550 A7 B7 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed V. Invention Description (5) (b) According to the result of the plasma treatment, (b - 1) is processed When the processing rate on the outer peripheral side of the body is lower than the processing rate on the center side, the impedance and/or the dielectric constant of the focus ring are increased, and the (b - 2 ) object to be processed is increased. When the processing rate on the outer peripheral side is higher than the processing rate on the center side, the impedance of the focus ring and/or the dielectric constant are lowered in accordance with the degree, and a new focus ring of at least one of a material, a size, and a shape is prepared. The process, and (c) using the prepared new focus ring, the plasma treatment process is carried out under the processing conditions of the above process (a). According to the plasma treatment, the phase difference between the outer peripheral side and the center side of the object to be processed due to the influence of the focus ring can be reduced, and the plasma treatment of the object to be processed can be performed uniformly. According to a second aspect of the present invention, in a plasma processing apparatus including the above-described shielding ring, when the object to be processed is subjected to an etching treatment or another plasma treatment, the plasma can be improved in uniformity of the plasma treatment. In the present inventors, the inventors of the present invention etched the tantalum oxide film using a plasma processing apparatus including a shadow ring made of quartz (S i 〇 2), and reviewed various causes of an increase in the etching rate on the outer peripheral side of the photoresist film. As a result, the following matters were known. That is, the surface of the shadow ring 6 is subjected to ion attack in the plasma during etching. At this time, since the shadow ring 6 is formed by quartz, the following reaction occurs by ion attack, and a reaction product such as oxygen is generated from the S i〇2 (please read the precautions on the back). This page) %> : Packing · Book d This paper scale applies to China National Standard (CNS) A4 specification (210X297 mm) -8 - 1250550 Ministry of Economic Affairs Intellectual Property Bureau employee consumption cooperative printed A7 B7 V. Invention description (6 ) between the two electrodes 1, 2. In particular, if there is a phase difference between the inner peripheral end of the shield ring 6 and the electrode material as shown in Fig. 15, the phase difference portion is easily splashed, and the oxygen release amount from the shadow ring 6 is obtained. Will increase. As described above, it is estimated that the etching rate of the photoresist film is increased on the outer peripheral side of the wafer 8 from the center side due to the influence of the oxygen gas, and is uneven. S i 〇 2+ CxFy - S i F4f + C 〇 + 〇 2 Further, the problem of such oxygen generation is not limited to quartz. It is common to the shielding ring 6 composed of other inorganic oxides. The present invention provides a plasma processing apparatus according to the above findings, comprising: a processing container; and a first electrode disposed in the processing container; and the processing unit disposed in parallel with the first electrode a second electrode that holds the object to be processed, a high-frequency power source that applies at least high-frequency power to the first electrode, and an inorganic oxide that covers an outer peripheral portion of the first electrode opposite to the second electrode The shielding ring is configured to generate a plasma between the first and second electrodes by applying a local frequency power according to the tubular power source, and the plasma is configured to process the object to be processed, and simultaneously with the shielding ring The contact portion of the plasma is covered with a plasma resistant film. According to the plasma processing apparatus, in the plasma processing apparatus including the shielding ring formed of the inorganic oxide, when the plasma is processed by the object to be processed, the uniformity of the plasma treatment can be improved. The invention further provides a plasma processing device, which belongs to the Chinese National Standard (CNS) A4 specification (210X297 mm) which is applicable to the scale of the photoresist paper, >I-------" -----, order------- (Please read the notes on the back and fill out this page) -9 - 1250550 A7 B7 V. Inventions (7) (Please read the notes on the back and fill in This is a plasma processing apparatus for performing a uranium engraving treatment of the film in accordance with the shape of the photoresist film, and is characterized in that: a processing container is provided and disposed in the processing a first electrode in the container, a second electrode disposed in the processing container in parallel with the first electrode to hold the object to be processed, and a high-frequency power source for applying at least high-frequency power to the first electrode, and covering and a shielding ring formed by at least the inorganic oxide of the outer surface of the second electrode facing the outer surface of the first electrode; and a plasma is generated between the first electrode and the second electrode by applying high frequency power according to the high frequency power source By the plasma formed in the object to be treated Subjected to the processing of uranium moment, at the same time, the contact portion of the shield ring plasma in plasma resistance to be covered by the film. According to the plasma processing apparatus, in the plasma processing apparatus including the shielding ring formed of the inorganic oxide, the etching of the photoresist film can be uniformized, and the uniformity of etching of the thin film can be improved. According to a third aspect of the present invention, there is provided a small-sized plasma processing apparatus which can improve the E X B drift effect of electrons from the W side to the E side in the vicinity of the lower surface of the upper electrode, thereby obtaining uniform plasma density. In order to achieve the object, the present invention provides a plasma processing apparatus, comprising: a processing container, and a central electrode disposed in the processing container and electrically grounded at the same time And a first electrode surrounding the high-frequency electrode on the outer circumference of the central electrode, and a second electrode disposed in parallel with the first electrode in the processing container to hold the object to be processed having the surface to be processed, and An applied magnetic field mechanism for forming a magnetic field having a certain directivity to the processed surface of the object to be processed, and the paper size is applicable to the Chinese National Standard (CNS) A4 specification (210×297 mm) ~ " 'Ministry of Economics, Intellectual Property Bureau, Staff and Consumers Co., Ltd. Printed 1250550 A7 B7 V. INSTRUCTIONS (8) A high-frequency power source that applies high-frequency power to at least the high-frequency electrode of the first electrode; from the above-mentioned high-frequency power source to the above-mentioned high-frequency electrode For the power supply, only the power supply contact on the west side of the magnetic field of the high-frequency electrode is performed. According to the plasma processing apparatus, a stronger electric field is formed on the W side of the high-frequency electrode of the first electrode than on the other pole side, so that the relatively low magnetic field on the W side formed by the applied magnetic field mechanism can be compensated for. Thus, in the vicinity of the surface of the high-frequency electrode on the side of the object to be processed, the EXB drift effect of electrons from the W side to the W side can be improved. Therefore, it is possible to provide a small-sized plasma processing apparatus which can obtain uniform and high density of plasma density. Further, in the plasma processing apparatus, the focus ring is electrically connected to the periphery of the high-frequency electrode of the first electrode, so that the uniformity of the processing rate on the outer peripheral side of the object to be processed can be improved. In this case, it is preferable to have an insulating member interposed between the center electrode of the first electrode and the high-frequency electrode. As a result, a parasitic capacitance is formed in the insulating member. Therefore, when the power contact is applied only to the W side, the resistance component of the parasitic capacitance can be reduced from the W side toward the downstream side (S side, N side, E side). Current and electricity. As a result, a strong electric field occurs relatively on the W side, and a weak electric field can relatively occur on the downstream side (S side, N side, E side). Further, since the second electrode constitutes high-frequency power for plasma generation and biasing, processing components such as an etchant in the plasma can be efficiently incident on the surface to be processed of the object to be processed. (Best form for implementing the invention) The first embodiment of the paper scale applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) " -11 - I--------0^----Ί ——, 玎——---------0 (Please read the note on the back and fill out this page) 1250550 A7 ___ B7__ V. Invention description (9) First, refer to Figure 1 to Figure 5 A first embodiment of the present invention will be described. (Please read the precautions on the back side and fill out this page.) As shown in Fig. 1, the plasma processing apparatus 10 used in the plasma processing method of the present embodiment is provided with a processing container made of a conductive material such as aluminum. 1 1. In the processing container 1 1, the lower electrode 1 2 and the upper electrode 13 are disposed to face each other in parallel. The lower electrode 12 disposed at the bottom of the processing container 1 is made of aluminum, and the wafer 8 as the object to be processed is placed and held. The upper electrode 13 disposed at the top of the processing container 1 is a supply unit that also has a processing gas. The Ministry of Economic Affairs, Intellectual Property Office, Staff Consumer Cooperative, printed on the lower electrode 12, via the matcher 1 4 A, connected to the first high frequency power supply 14 . On the other hand, the upper electrode 13 is connected to the second high-frequency power source 15 having a higher frequency from the first high-frequency power source via the matching unit 15 5 A. At the upper electrode 13, a gas supply source 16 is connected to the mass flow controller 16 6 via a valve 16 A. A processing gas such as a fluorocarbon gas is supplied from the gas supply source 16 to the upper electrode 13. Further, an exhaust port 1 1 A is formed on the bottom surface of the processing container 1 1. Further, the inside of the processing container 1 is exhausted via an exhaust unit (not shown) connected to the exhaust port 1 1 A to maintain the degree of vacuum generated by the processing gas. For example, in the state in which the processing gas is maintained at a predetermined degree of vacuum in the processing container 1 1 , the first high-frequency power of 2 Μ Η z is applied from the first high-frequency power source 14 to the lower electrode 1 2 while being the second highest. The frequency power source 15 applies a second high frequency power of 60 ΜΗ to the upper electrode 13. The plasma of the processing gas is generated between the lower electrode 12 and the upper electrode 13 by the action of the second high-frequency power, and the bias voltage occurs according to the function of the first high-frequency power, and the Chinese national standard is applied ( CNS ) Α 4 specifications (210 Χ 297 mm) -12- 1250550 Ministry of Economic Affairs Intellectual Property Bureau employee consumption cooperative printed A7 B7 V. Invention description (1〇) at the lower electrode 1 2 . Thereby, the wafer 1 on the lower electrode 1 2 can be subjected to plasma treatment such as reactive ion uranium engraving. Further, on the outer peripheral side of the upper surface of the lower electrode 12, a focus ring 17 surrounding the outer periphery of the wafer 8 is disposed. The focus ring 17 is used to concentrate the electrical edge on the wafer 8. An electrostatic chuck 18 connected to a high voltage DC power source 18A is disposed above the lower electrode 12. The electrostatic chuck 18 electrostatically adsorbs the crystal 8 by a high voltage direct current voltage applied from a high voltage direct current power source 1 8 A. A cooling mechanism 19 and a heating mechanism (not shown) are provided in the lower electrode 1 2, and the wafer 8 is adjusted to a predetermined temperature by the cooling mechanism 19 and the heating mechanism. In the lower electrode 12, a gas passage 1 2 A through which a gas (e.g., H e gas) as a heat transfer medium flows is formed in a plurality of positions on the upper surface. A plurality of holes 18B corresponding to the openings of the gas passages 1 2 A are formed in the electrostatic chuck 18. The heat transfer between the lower electrode 12 and the wafer 8 can be promoted by supplying Hee gas from the holes 18B to the fine gaps between the wafer 8 and the electrostatic chuck 18. A bellows 20 made of, for example, aluminum is interposed between the lower surface of the lower electrode 12 and the bottom surface of the processing container 1 1 . Moreover, the lower electrode 1 2 is lifted and lowered by a lifting mechanism (not shown), and the distance from the upper electrode 13 can be appropriately set in accordance with the type of plasma treatment. The upper electrode 13 has a plate-shaped electrode material 13 A and a hollow support 1 3B that detachably supports the electrode material 13A. In the electrode material 1 3 A and the support 1 3 B, a plurality of pores 1 3 C which are mutually coincident are formed. These holes 1 3 C are uniformly dispersed and supplied from the gas supply source 16 by the processing gas supplied from the upper electrode 13 to the overall processing volume. The Chinese National Standard (CNS) A4 specification (210×297 mm) is applied. " -13- (Please read the note on the back first, then fill in the item · install :- write this page) 4 1250550 Α7 Β7 5, invention description (11) inside the device 1 1. Further, in Fig. 1, the symbol 2 2 is a high-pass chopper that filters the high-frequency current flowing from the second high-frequency power source 15 into the lower electrode 12; and the symbol 2 3 is passed from the first high-frequency power source 1 4 A low-pass chopper that flows into the high-frequency current of the upper electrode 13. However, the electric field formed between the lower electrode 1 2 and the upper electrode 13 by the second high-frequency power is changed by the material of the focus ring 17 . This is possible by changing the phenomenon that the second high-frequency current of the focus ring 17 is easily penetrated by the difference in the impedance of the material. That is, when the impedance of the focus ring 17 of the high-frequency current is high, the second high-frequency current does not easily penetrate the focus ring 17' and no plasma is generated above the focus ring 17. Therefore, by suppressing the diffusion of the plasma and sealing it in the range of the wafer 8, the plasma density on the outer peripheral side of the wafer 8 can be increased and the electron density can be increased. Thereby, the etching rate of the outer peripheral side of the wafer 8 can be relatively increased. On the one hand, when the impedance of the focus ring 17 is low, the second high frequency current easily penetrates the focus ring 17 and plasma is also generated above the focus ring 17. Therefore, the plasma is easily diffused to the outside in the radial direction of the focus ring 17, and the plasma density is lowered on the outer peripheral side of the wafer 8, and the etching rate is also lowered. The impedance Z of the focus ring 17 for the high-frequency current is composed of the resistance (R) component and the reactance (X) component. The resistance component is defined by the resistivity p of the material of the focus ring 17 and the projection area 5 and the length (thickness) d in the axial direction as shown in the formula 1. Further, as shown in the formula 2, the reactance component is defined by the dielectric constant ε r of the material of the focus ring 17 and the projected area 5 and the length (thickness) d in the axial direction (however, ε is the dielectric constant of the vacuum) ). The paper scale applies to the Chinese National Standard (CNS) Α4 specification (210x297 mm) '~~' -14 - (Please read the notes on the back and fill in the following: Write this page) Ministry of Economic Affairs Intellectual Property Office Staff Cooperatives Print 1250550 A7 ______ B7___ V. Description of invention (1 bow R = P*d/S ............1 X = -l/C*w =, l/(s,sr*S/d *f0 Further, the material of the focus ring 17 is composed of the R component and the X component, and thus can be represented as a circuit shown in Fig. 2. The circuit has two kinds of currents. The parallel circuit of the path is thus transformed into a series circuit which is normalized by a series circuit. The resistance 値 of the parallel circuit of the material is defined as RP; the electrostatic capacitance is defined as C p ; the reactance is defined as XP; The transformed resistance 値 is defined as R s ; when the reactance is defined as X s , the transformation is expressed by Equations 3 and 4.

Rs = Rp/(l + cu2*Cp2*Rp2) ...3

Xs = -co*Cp*Rp2/(l + w2*Cp2*Rp2) ...4 Thus, a material having a physical property 値 (resistivity p, dielectric constant ε r , electrostatic capacitance C p ) shown in the following table is used, That is, using 矽(S i ), two kinds of carbonized bismuth (S i C — 1 , S i C - 2 ) having different resistivity, oxidation pin (Z r〇2 ) and aluminum nitride (A 1 N ), respectively Make a focus ring. Further, the impedance Z of the focus ring of each material after normalization is obtained, and is shown in the next table. Further, the next table also shows that there are other physical properties of the wafer 8 and the like. This paper size applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) ' ' -15- 1' mn mu n - In m» =_ (Please read the note on the back and fill in the tribute) Ministry of Intellectual Property Bureau Staff Consumer Cooperative Printed 1250550 Α7 Β7 V. Invention Description (13) P Tao £r Parallel CP [PF] Parallel Rp [Ω] Parallel XP Series Rs ϋΩ] [Ω] Series X jj〇L Normalized ΖΓΩ1 Wafer 0.02 12 4760 4.5x 10_4 -0.56 4·5χ l〇4 -3.6xl〇·7 0.0004 Si 0.02 12 200 l.lx 10'2 -14 l.lx l〇'2 -8.7xl〇'6 0.01 SiC -1 5x 102 18 290 2.7x 102 -9.1 3.0X101 -9.05 9.05 SiC-2 5x 105 18 290 2.7x 105 -9.1 3.0x 1024 -9.05 9.0 Zr〇2 7x 105 30 490 3.8x 105 -5.4 7.7x 10_5 - 5.44 5.44 AIN lx 107 7 110 5.4x 106 -23 9.9x 10*6 -23.3 23.3 (Please read the notes on the back and fill in. : Write this page) Printed and used by the Intellectual Property Office of the Ministry of Economic Affairs The focus ring of each material is uranium-etched with a blanket-tantalum oxide film of the wafer 8 under the following processing conditions. Thereafter, the etching rate of each portion of the wafer 8 was measured, and the measurement results are shown in Fig. 3. (Processing conditions) Wafer diameter: 200mm Etched film: Overlay layer - tantalum oxide film Upper electrode: Power supply frequency = 60MHz, power supply =

1 5 0 0 W

Lower electrode: power supply frequency 2 2MH z, power supply power 2 1 600 W Interelectrode gap: 2 5 mm Processing pressure: 20m Torr This paper scale is applicable to China National Standard (CNS) A4 specification (210 X 297 mm) -16 - 1250550 Ministry of Economic Affairs Intellectual Property Office Staff Consumer Cooperatives Printed A7 B7 V. Description of Invention (Processing Gas (Flow): C4F8 (8sccm), Ar (3〇Osccm), 〇2 (8sccm) According to the results shown in Figure 3 In the focus ring of the known S i , the etching rate is reduced on the outer peripheral side of the wafer 8. For this, in the focus ring of the material other than S i , the uranium engraving rate on the outer peripheral side of the crystal _ 8 and S i is higher in comparison. This is because the impedance Z and S i of these materials are 2 to 3 digits higher, which makes the high-frequency current not easy to flow. However, the observation depends on S i C - 1 and S When the focus ring of i C — 2 is the latter, the latter is three digits higher than the resistance R s of the former, but the etching rate is almost unchanged. This may be that the capacitive reactance X s is higher than the resistance R s by the high frequency current. The flow, only the resistance rs, and can not make the impedance Z excessively change. According to Z r〇2 In the case of the focal ring, the resistance @Z is slightly lower than that of the S i C - 2 , but the etching rate on the outer peripheral side of the wafer 8 is rather high. Moreover, the impedance Z is the highest when the focus ring of A 1 N is used. However, the etching of the outer peripheral side of the wafer 8 has a tendency to decrease, which may be due to the fact that the reactance X s contributes to the etching rate in addition to the impedance z. The influence of X s. In the field of the screen formed between the focus ring 17 and the wafer 8 and the plasma, there may be an equal circuit shown in Fig. 4. In Fig. 4, the Vsl is on the wafer. Screen voltage; V-system wafer voltage; vs 2 system sheath voltage on the focus ring; vfr is the voltage of the focus ring. The voltage of the wafer is V = 〇, which may be the resistance of the wafer R p and others The material is relatively small, so it is almost short-circuited by the lower electrode 12. As can be seen from Fig. 4, the paper size of the lower electrode 12 is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm). ----Ί.--订------I (please read the notes on the back and fill out this page) -17- 1250550 A7 B7 V. Invention (1 The voltage of the part of the bow wafer 8 and the part of the focus ring 17 can be set to 5. (Please read the note on the back and then fill in this page) V s 1 = V s 2 + V f Γ .... ..5 Here, by V = Q / C (the charge of the Q system is constant in the electrode which jumps into the lower electrode 1 2), the larger the electrostatic capacitance C of the focus ring 17 is, the smaller the V fr is. The larger the ground capacitance C is, the larger V s 2 is and close to V s 1 . The screen voltage V e d g e on the outer peripheral side of the wafer is the middle of V s 1 and Vs2. Therefore, the larger the electrostatic capacitance of the focus ring 17 is, the higher the V e d g e is, and the higher the etching rate is. Therefore, it can be seen that the higher the capacitance of the focus ring 17 is, the higher the etching rate on the outer peripheral side of the wafer is. Therefore, it is understood that the focus ring 17 not only has its impedance Z, but also the reactance X S affects the height of the etching rate on the outer peripheral side of the wafer. The Ministry of Economic Affairs, the Intellectual Property Office, and the Consumer Cooperatives Co., Ltd. printed and determined the relationship between the impedance Z (Ω) and the dielectric constant ε r of the focus ring formed by the various materials in the above table, and the uniformity of the etching rate (±%). The result is indicated by a 〇 mark in Fig. 5. The negative number in Fig. 5 indicates that the etching rate on the outer peripheral side of the wafer is higher than the center side. Further, a positive number indicates that the etching rate on the outer peripheral side of the wafer is lower than that on the center side. According to the result shown in Fig. 5, the larger the impedance Z and/or the medium constant ε r , the larger the number 均匀 of the uniformity becomes on the negative side. That is, the etching rate on the outer peripheral side of the wafer is higher than that on the center side. Conversely, the smaller the impedance Z and/or the medium constant ε r , the larger the number 均匀 of the uniformity becomes on the positive side. That is, it means that the etching rate on the outer peripheral side of the wafer tends to be lower than that on the center side. Thus, among the above processing conditions and materials, the focus ring according to Z r 0 2 is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) -18- 1250550 A7 ___ B7

V. Description of the invention (W is the best uniformity between 1 and 0. 0% and 1 to 3. 0%. Also, the uniformity of A 1 N is inferior to zr〇2, in a 3 Between 0% and 1/4%. However, the uniformity of the focus ring according to S i C is about + 5 · 0 %, which is worse than the above two. Moreover, it is known that the conventionally known S i The uniformity of the focus ring is more than §. 〇%. Considering the further miniaturization in the future, the uniformity of the uranium engraving rate is preferably ±4.0% or less, and more preferably ±3.0% or less. For example, In the case of Fig. 5, as the material of the focus ring, the range in which the impedance z is in the range of 1 to 2 5 Ω and the dielectric constant ε r is surrounded by the dotted line of 2 1 to 3 0 is used, or the impedance Z is in the range of 1 2 to 2 A material having a range of 5 Ω and a dielectric constant surrounded by a dotted line of 5 to 30, a uniformity of ± 4 · 0 % or less can be obtained. Further, an impedance Ζ is used at 13 3 to 2 1 Ω and a dielectric constant ε r is used. The material in the range surrounded by the solid line of 5 to 2 9 can obtain a uniformity of ±3.0% or less. As a material of the focus ring of such physical properties, such as chromium oxide, the nitride is more appropriately made. In addition, a combination of a ring of zirconia and a ring made of alumina is used, or a composite material of mixed chrome oxide and tantalum carbide, or a composite material of mixed aluminum nitride and carbonized sand, etc., of course, at least two in the composite material. The above-described bonded body in which a ring composed of a single material is joined also includes a joined body of a composite material composed of two kinds of bonded plural materials. Further, a desired impedance Z can be realized and a projected area s in order to adjust the axial direction of the focus ring is obtained. And / or the length (width) d, the size and shape may be changed. According to the above, the electric prize processing method according to the present invention is performed in the following order using the plasma processing apparatus 1 configured as described above. This paper size applies to the Chinese National Standard (CNS) A4 specification (21〇><297 mm) ' -19- ---------^-- (Please read the notes on the back first) Fill in this page) Order Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed 1250550 A7 B7 V. Invention Description (a) First, use a certain material, size and shape of the focus ring 1 7 in certain processing conditions (such as Under the processing condition A), the etching treatment of the crystal _ 8 is performed. (Please read the note on the back side and then fill in the page.) (b) Hereinafter, the etching rate on the wafer 8 obtained as a result of the uranium engraving treatment is obtained. Distribution, (b - 1 ) When the etching rate on the outer peripheral side of the wafer 8 is lower than the uranium engraving rate on the center side, the impedance Z and/or the dielectric constant ε r of the focus ring 17 are increased with the degree ( b — 2) When the uranium engraving rate on the outer peripheral side of the wafer 8 is higher than the uranium engraving rate on the center side, the impedance Z of the focus ring 17 and/or the dielectric constant ε r are lowered in accordance with the degree, and the material is prepared to be changed. A new focus ring 17 of at least one of size and shape. (c) Thereafter, an etching process is performed under the processing conditions of the above (a) process using the prepared new focus ring 17 . Printed by the Intellectual Property Office of the Ministry of Economic Affairs and the Consumer Cooperatives. The process of (b) and (c) may be repeated by the etching process of the above (c) process. On the other hand, if the result of the (c) process is satisfactory, the changed focus ring 17 is used and the process (c) is repeated only as needed. According to the plasma processing method of the present embodiment, the phase difference between the outer peripheral side and the center side of the wafer 8 due to the influence of the focus ring 17 can be reduced, and the etching of the wafer 8 can be performed uniformly. deal with. Further, the material for forming the focus ring used in the present invention is not limited to the above embodiment, and may be a composite material which is required to mix or bond various materials. Further, in the present embodiment, the etching process is taken as an example. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X 297 mm). -20- Ministry of Economic Affairs Intellectual Property Office Staff Consumer Cooperative Printed 1250550 A 7 ____________ V. (Description of the Invention) The present invention is also applicable to other plasma treatments. Second Embodiment Hereinafter, a second embodiment of the present invention will be described with reference to Figs. 1 and 6 to 0. The plasma processing apparatus of the present embodiment basically has the same configuration as the apparatus of the first embodiment shown in Fig. 1. Therefore, the same components are denoted by the same reference numerals, and the description thereof will not be repeated. As shown in Fig. 6, the upper electrode 13 of the present embodiment has, for example, a plate-shaped tantalum electrode material 1 3 A, and a hollow aluminum support body 1 3B that detachably supports the electrode material 13A. On the outer peripheral side of the electrode material 1 3A, a thin portion 1 3 C is formed on all the entire circumferences. The electrode material 1 3 A is attached to the support body 1 3 B in the thin portion 1 3 C by a plurality of bolts 1 3 P. The bolts 1 3 D are equally spaced A shadow ring 2 1 is attached to the upper electrode 13 in the circumferential direction of the thin portion 1 3 C. The shadow ring 2 1 is made of an inorganic oxide such as quartz or alumina (in the present embodiment, quartz is used). The shielding ring 2 1 covers the outer peripheral surface of the upper electrode 1 3 and the thin portion 1 3 C of the electrode material 13 A, and is on the lower surface side of the upper electrode 13 to be the same as the electrode material 13 3 A. The masking ring 21 covers a portion of the thin portion 1 3 C of the electrode material 1 3A, and is formed as a flange portion 2 1 A. The lower surface of the flange portion 2 1 A is covered with the plasma resistant film 21B. The shadow ring 21 does not directly contact the plasma. The so-called plasma resistant film refers to the plasma resistance, and even if it is subject to the paper size, the Chinese National Standard (CNS) A4 specification (210X297 mm) I ---- --IT-------Aw (Please read the note on the back and fill out this page) -21 - Ministry of Economic Affairs, Intellectual Property Bureau, Staff Consumer Cooperative, Printed 1250550 A7 ______B7 _ V. Invention Description (Ion attack A film of oxygen or a pollutant may occur. The electric resistance film 2 1 B is oxidized by, for example, i. Y 2 〇 3 ) is formed by an oxide of an olefinic element or a heat-resistant resin such as a polyimide-based resin. The yttrium oxide film is formed by spraying a ruthenium oxide with atmospheric plasma to form an appropriate film thickness. The thickness of the film is not particularly limited, but is preferably, for example, a thickness of from 10 to 50 Å//m. As a film of the polyimide film, a bonding tape made of, for example, a polyimide resin is used. Ideally, the lanthanum oxide system contains an oxygen atom in the crystal structure as in the case of quartz. However, the binding amount of the ruthenium atom to the oxygen atom is high and stable, so even if the ruthenium oxide is subjected to ion attack, it is difficult to completely split the Y-turn bond, and the dissociation of the oxygen atom can be particularly suppressed. Polyimide-based resins are also thermally stable, and can suppress the dissociation of oxygen atoms generated by ion attack. Therefore, even if the shadow ring 21 of the upper electrode 13 is subjected to ion attack, the occurrence of oxygen from the shadow ring 2 1 can be suppressed exceptionally. Therefore, in the outer peripheral side of the wafer 8, the etch rate of the photoresist film on the wafer 8 can be made uniform without increasing the uranium engraving rate of the photoresist film by conventionally using oxygen plasma. On the other hand, when the etching rate of the photoresist film on the outer peripheral side of the wafer 8 is increased, it is understood that the plasma on the outer peripheral side of the wafer 8 is in a state of concentrated oxygen. For example, when the ruthenium oxide film is etched using a fluorocarbon gas (C x F y ), if the shadow ring 2 1 is covered by the plasma resistant film 2 1 B, the plasma on the outer peripheral side of the wafer 8 does not become concentrated oxygen. In the case of 'the etch rate of the photoresist film can be uniformized. Further, when the plasma on the outer peripheral side of the wafer 8 becomes concentrated oxygen, the etching rate of the portion of the photoresist film becomes high, and the following phenomenon occurs. That is, on the outer peripheral side of the wafer 8, the side paper size in the opening of the tantalum oxide film which is etched and etched is applied to the Chinese National Standard (CNS) A4 specification (210×297 mm). I Ί—IT-- -----Aw ~^ (Please read the note on the back and fill out this page) - 22- 1250550 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed A7 B7 V. Invention Description (F-polymer of wall protective film) Or CF ions in the plasma in the opening react with oxygen to form C〇 and C〇2. Thereby, in the outer peripheral side of the wafer 8, the plasma in the opening becomes a concentrated fluorine state and rises relatively. The etching rate of the tantalum oxide film is expanded by the sidewall of the opening, so that the uniformity of the erbium oxide film on the wafer 8 is deteriorated, and the shape of the etching is deteriorated. However, in the present embodiment, Due to the effect of the plasma-resistant film 2 1 B, the plasma does not become concentrated in the outer peripheral side of the wafer 8, so that not only the photoresist film but also the uranium engraving rate itself of the tantalum oxide film can be uniformed. In all of the wafer 8, all of them become vertical in the opening of the tantalum oxide film. When the uranium is engraved with an oxide film, for example, it is shown in the form of (a) to (f) in Fig. 8 (again, the letter sequence code used in Fig. 8 is different from the chemical formula, etc.). The wafer 8 of the eighth (a) diagram has a tantalum oxide film S and a photoresist film R on the crucible S. When the tantalum oxide film S 0 of the wafer 8 is to be etched, 'the pattern of the photoresist film R is fixed. At this time, in the present embodiment, oxygen does not easily occur from the shadow ring 21, so that the uranium engraving rate of the photoresist film R can be made uniform even in all of the wafers 8. The oxide film S 〇 is uniformly etched to form vertical sidewalls. In particular, when the ruthenium oxide film R is BPSG, Boeing is likely to be generated by the influence of oxygen, but in the present embodiment, Boeing can be prevented. It is shown in the eighth (b). The wafer 8 of the figure has a sand nitride film SN and a photoresist film R on the tantalum oxide film S, and the paper size shown in the figure 8 (c) applies the Chinese National Standard (CNS) A4 specification (210X297). )) I ------ ------ Aw L (please read the note on the back and fill out this page) -23- 1250550 A7 B7 (Invention) (21) (Please read the precautions on the back and fill out this page.) The wafer 8 system has a polysilicon film PS and a photoresist film R on the oxide film S. These cases are also shown in the 8th. (a) Wafer 8 of the figure Similarly, the etching rate of the photoresist film R can be made uniform in all of the wafers 8, and uniform etching can be applied to the tantalum oxide film S 。. (d) The wafer 8 of the figure has aluminum, sand and copper metal AL and a photoresist film R on the crucible S. At this time, oxidation of the alloy film AL on the outer peripheral side of the wafer 8 can be suppressed. The wafer 8 shown in Fig. 8(e) is a sand oxide film S〇 and a tungsten film M W . When the tungsten film M W of the wafer 8 is planarized, oxidation of tungsten on the outer peripheral side of the crystal 8 can be suppressed. The wafer 8 shown in the eighth (f) has a polysilicon film P S covered with a tantalum nitride film S N , a tantalum oxide film S 0 and a photoresist film R. When the wafer 8 is self-aligned contact hole (SAC) etched, the influence of oxygen can also be suppressed. When the wafer 8 is comprehensive, the uranium engraving rate of the photoresist film R can be made uniform, and uniformity can be applied. SAC etching. According to the present embodiment, the Ministry of Economic Affairs, the Intellectual Property Office, and the employee's consumer cooperative are printed with the plasma-resistant film 2 1 B covering the contact portion with the plasma of the quartz shield ring 2 1 . In the plasma treatment, generation of oxygen depending on the ion attack on the shadow ring 2 1 can be prevented. Therefore, the plasma on the outer peripheral side of the wafer 8 does not become concentrated, and the etching rate of the photoresist film on the outer peripheral side of the wafer 8 can be prevented from increasing. Thereby, the etching rate of the photoresist film on the wafer 8 can be made uniform, and the etching rate and shape of the tantalum oxide film on the wafer 8 can be made uniform. Hereinafter, Fig. 7 is a view showing a modification of the upper electrode 13 in Fig. 6 . It is shown in Figure 7 above the electrode 1 1 3 , which has the paper size applicable to China National Standard (CNS) A4 specification (210X297 mm) 24- 1250550 A7 B7 V. Invention description (22) Tanning electrode material 1 1 3A The support 1 1 3B and the shadow ring 1 2 1 are the same as those shown in FIG. 6 except that the shapes of the electrode material 1 1 3 A and the shadow ring 1 21 are different. The electrode material 1 χ 3A as a whole is formed to have the same thickness. Further, the plurality of bolts 1 1 3 D connecting the electrode material 1 1 3 A and the support body 1 1 3 B are covered by the flange portion 121A ' of the shadow ring 121. The flange portion 1 2 1 A has a step difference from the surface below the electrode material 1 3 1 A, and is different from that shown in Fig. 6. Further, the lower surface of the flange portion 1 2 1 A and the inner peripheral surface which is stepped, that is, the portion in contact with the plasma, is covered by the plasma resistant film 1 2 1 A. At this time, the generation of oxygen from the shadow ring 1 2 1 at the time of plasma treatment can be suppressed, and the same effects can be expected. Hereinafter, specific embodiments of the embodiment will be described. [Embodiment 1] In the present embodiment, a spray film of ruthenium oxide was used as the plasma resistant film 2 1 B. Further, under the following processing condition B, the distance between the lower electrode 1 2 and the upper electrode 13 was set to 21 mm, 25 mm, and 35 mm', and the uranium engraving rate of the photoresist film in each case was measured. The result is shown in Fig. 9. (Processing condition B) Wafer diameter: 200 mm Photoresist film: K r-F photoresist film is etched: tantalum oxide film Processing content: forming contact holes The paper size is applicable to China National Standard (CNS) A4 specification ( 210X297 mm) I---------Lesson - (Please read the notes on the back and fill out this page) Book 4 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed -25 - 1250550 A7 B7 V. Description of invention (23) Upper electrode: power supply frequency = 6 ΟΜΗζ, power supply =

1 5 0 〇 W Lower electrode: Power frequency = 2 ΜΗ ζ, power supply =

1 6 0 〇W Processing pressure: 2〇m Torr process gas (flow rate); C4F8 (8sccm), Ar (300sccm), 〇2 (8sccm) according to the results shown in Figure 9, and shown in Figure 16 ( As compared with the results of the conventional plasma processing apparatus of the plasma-free resistant film, it is understood that the etch rate of the photoresist film on the wafer 8 can be uniformized while suppressing an increase in the uranium engraving rate on the outer peripheral side of the wafer 8. From this, it is also apparent that the plasma resistant film 2 1 B is covered on the shadow ring 2 1 , and generation of oxygen on the outer peripheral side of the wafer 8 can be suppressed, and it is possible to suppress the adverse effect of oxygen on etching in an exceptional manner. In the present embodiment, the same measurement as in the first embodiment was carried out using a polyimide film (specifically, a Kapton (trademark) tape) as the plasma resistant film 2 1 B. Further, as shown in Fig. 10, in the present embodiment, the same effect as that of the first embodiment can be obtained. Further, in the present embodiment, a case where a ruthenium oxide sprayed film or a polyimide film is used as the plasma resistant film will be described. However, the present invention is a plasma resistant film which covers the shadow ring and can suppress the occurrence of oxygen. Special restrictions. Further, in the present embodiment, a quartz mask ring is exemplified, and the paper size is applied to the Chinese National Standard (CNS) A4 specification (210〆297 mm) I--------*· (Please read the notes on the back and fill out this page.) Order d Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed -26- 1250550 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed A7 B7 V. Invention Description (24) The shadow ring to be used in the present invention is not particularly limited as long as it is composed of an inorganic oxide that emits oxygen when exposed to plasma, and in the present embodiment, an uranium engraving treatment is exemplified. However, the present invention is also applicable to other plasma treatments such as CVD. Further, in the case where the protective cover or the focus ring attached to the lower electrode is formed of an inorganic oxide such as quartz, the same effect can be expected when the member is covered with the plasma resistant film. (THIRD EMBODIMENT) Hereinafter, a third embodiment of the present invention will be described with reference to Figs. 1 to 14 . In the following, the same components as those having the same functions and configurations are denoted by the same reference numerals, and the description thereof will not be repeated. Fig. 1 is a cross-sectional view showing the plasma processing apparatus of the embodiment taken along the w-electrode direction of the magnetic field of the magnet 138 described below. The plasma processing apparatus 1 shown in Fig. 1 is provided with a cylindrical processing container 1 〇 4 which forms a processing plasma processing chamber) 102. The processing container 104 is configured to be hermetically sealed, and is made of aluminum or the like which is treated with acid-resistant tin, and is grounded via the grounding wire 1 〇 6 . Further, in the processing chamber 102, a conductive lower electrode 1 0 8 which is a mounting surface of the wafer 8 is disposed. An electrostatic chuck 1 10 for adsorbing and holding the wafer 8 is provided on the mounting surface of the lower electrode 110. The electrostatic chuck 1 10 has a structure in which both sides of the conductive film are sandwiched by a polyimide resin. The voltage is from the standard of the paper set outside the processing container 104. The Chinese National Standard (CNS) A4 specification (210X: 297 mm) I, 丨丨 '订---------01 (please first Read the notes on the back and fill out this page.) -27- 1250550 Ministry of Economic Affairs Intellectual Property Office Staff Consumer Cooperatives Print A7 B7 V. Invention Description (25) A DC power supply (not shown) is applied to the film by the Coulomb The force adsorption holds the wafer 8. Further, the electrostatic chuck 1 11 不 is not used, and the peripheral portion of the wafer 8 can be pressed by mechanical clamping, for example, to form the wafer 8 . Further, on the lower electrode 1 0 8 , a focus ring 1 1 2 which can surround the electrostatic chuck 1 10 is provided. The focus ring 1 1 2 is made of an insulating material such as quartz, and has a uniformity of uranium engraving rate on the outer peripheral side of the wafer 8, and is connected to the lower electrode 108 via the second matching unit 1 14 . The high-frequency power source 1 16 and the high-frequency power (5 0 to 2 500 W) of a predetermined frequency (for example, 1 3, 56 M Hz) are applied to the lower electrode 1 0 8 . With this configuration, the processing gas is plasmatized, and in the plasma processing, a bias voltage is applied to the electrode 10 8 placed on the lower surface of the wafer 8 to efficiently inject the uranium engraving agent in the plasma. The processed surface of the wafer 8. Further, in the processing chamber 102, the conductive upper electrode 1 200 facing the mounting table of the lower electrode 108 is disposed to constitute the top wall of the processing chamber 1 0 2 . As also shown in Fig. 2, the upper electrode 120 of the present embodiment is composed of a central electrode 1 2 2 having a disk-shaped upper portion and an upper ring electrode 1 2 4 surrounding the outer periphery of the central electrode 1 2 2 . . An upper focus ring 1 2 6 for improving the uniformity of the etching rate on the outer peripheral side of the wafer 8 is disposed around the upper ring electrode 1 2 4 . Further, the upper central electrode 1 2 2, the upper ring electrode 1 24 and the upper focus ring 1 2 6 are made of aluminum treated with alumite. Also, in the upper central electrode 1 2 2 and the upper ring electrode 1 2, the paper size applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) - -28-; Pack----Ί (Please read the back of the note first) Matters fill out this page) ------ d 1250550 A7 B7 5, invention description (26) 4, and between the upper ring electrode 丨 2 4 and the upper focus ring 丨 2 6 with quartz The insulating ring (insulator) is composed of 1 4 〇a, 1 40b. Further, the upper central electrode 1 2 2 and the upper focus ring 1 26 are grounded by a ground line 1 2 8 . The upper ring electrode 1 2 4 of the present embodiment is different from the conventional one, and the power supply from the high-frequency power source is performed only by the power supply contact 丨 3 4 on the W side of the magnetic field. That is, at the upper ring electrode 1 2 4, the first high frequency power source 1 3 2 is only connected to the power supply contact 1 3 4 on the W side via the first matching device 1 3 0, and a certain frequency is applied (for example, 1 〇〇) High frequency power of μ Η z ) (50~l〇〇〇W). In this manner, by configuring the frequency-frequency power from the first high-frequency power source 133 to be applied to the w-side power supply node 1 3 4 of the upper ring electrode 1 2 4, the upper electrode 1 2 0 is as follows. On the W side, an electric field stronger than the other pole sides can occur. Further, in the upper center electrode 1 2 2, a gas supply source (not shown) is supplied with a flow rate adjustment valve (not shown), and an opening/closing valve (not shown) and a gas discharge hole 1 2 2 a are supplied with, for example, A r , A treatment gas such as C 4 F 8 gas or CF 4 gas. The gas supplied into the processing chamber 102 is exhausted through a vacuum pump (not shown) such as a turbine molecular pump via an exhaust pipe 163 provided at the bottom of the processing chamber 102. The processing chamber 1 0 2 can be evacuated to any degree of reduced pressure. A permanent magnet (e.g., a dipole ring magnet) 138 is provided as a magnetic field forming mechanism for forming a magnetic field in the processing chamber 10 2 outside the processing chamber 1 0 2 . A magnetic field parallel to the processed surface of the wafer 8 and having a certain directivity is formed by the magnet 138. This paper scale applies to China National Standard (CNS) A4 specification (210X297 mm) (please read the note on the back and fill out this page) -裴- 4 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed -29- 1250550 A7 B7 V. DESCRIPTION OF THE INVENTION (27) The magnetic field distribution on the wafer 8 formed by the magnet 138 is described based on Fig. 3, and Fig. 3 is a view showing the plasma processing apparatus of the present embodiment. The vector and equal-intensity lines of the magnetic field on the wafer 8 represent a pattern of actually measuring the magnetic field distribution obtained by the magnetic field formed on the wafer 8. Further, the magnetic field distribution shown in FIG. The magnetic field distribution formed by the plasma processing apparatus is the same. As shown in Fig. 3, the magnetic field is formed on the wafer from the N side to the S side, and it is understood that the interval of the intensity line of the E-electromagnetic field is smaller than the w side. This means that the strength of the magnetic field formed on the E-electrode side is stronger than the magnetic field strength on the W side. In other words, the magnetic field strength on the W side is weaker than the magnetic field strength on the E side, and thus on the W side of the upper electrode. Near the bottom, the electron acceleration system on the E side is reduced. That is, the EXB drift effect as the overall plasma processing apparatus is reduced. In the present embodiment, in order to compensate for the relatively low magnetic field density formed on the W side, only the power supply from the high frequency power source is applied to the upper ring. The configuration of the W side of the electrode 1 2 2 is the electric contact point 134. By this configuration, a strong electric field for compensating a relatively low magnetic field density is formed on the W side, so that the Ex B drift effect can be improved. According to Fig. 14, a principle of applying a stronger electric field to the W side of the upper ring electrode and a relatively strong electric field on the W side will be described. First, as shown in Fig. 14, the upper ring electrode 1 of the present embodiment is shown. 2 4, is applied with high-frequency power, and can be regarded as an LC circuit with parasitic impedance L and parasitic capacitance C. At this time, the parasitic impedance L is the above-mentioned standard of the ring paper, which is applicable to the Chinese National Standard (CNS) A4 specification (210X297 public). PCT) (Please read the notes on the back and fill out this page)

, 1T

Jm Ministry of Economic Affairs Intellectual Property Bureau employee consumption cooperative printing -30- 1250550 A 7 _____B7_ V. Invention description (28) The pole 1 2 4 itself has a self-sufficient impedance L. Further, the parasitic capacitance C corresponds to the insulator 1 4 0 a, 1 4 0 b between the upper ring electrode 12 4 and the GND (that is, the upper central electrode 1 2 2 and the upper focus ring 1 2 6 ) (see the 1 2) and the field of plasma screens. The field of the screen electrode refers to an electron having a moving speed higher than the moving speed of ions in the plasma, and is deposited by a plasma formed by adhering to a member closer to the front of the ion or a surface such as a Changyuan. Bad field. Further, since the LC circuit (ring electrode 1 24) functions as a filter at a high frequency, the parasitic capacitance C of the insulator acts as an LC low-pass filter circuit which is output on the W side and is output on the E side. . The transmission efficiency of the fading current is mainly caused by the parasitic capacitance C of the insulator on the output side, which will be described below. In the LC circuit (upper ring electrode 1 2 4 ), the intensity E of the electric field generated on each pole side is expressed as follows (hereinafter, w, n, s, and e are added to correspond to W, N, S). , the various poles of E). W pole side: Ew=Iw* (Z〇-1/Cw 氺ω) Ν Polar side: En=In* (Z〇+ L*o− l/Cn*o) S pole side: Es = I s* ( Z〇+ L*0— 1/Cs 氺ω) E Polar side: Ee = I e* (Z〇+ 2*L*w− 1/Ce* ω ) (However, Z 0 : from the power supply to the W side Impedance, L: self-contained impedance, C: parasitic capacitance, I: current flowing on each pole side) This paper scale applies to China National Standard (CNS) Α4 specification (210Χ297 mm) (Please read the notes on the back and fill in the form) Page), 11 4 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed -31 - 1250550 A7 B7 V. Inventive Note (29) At this time, when the high-frequency current is supplied to the W-side power supply contact of the upper ring electrode 1 2 4 , the impedance of the parasitic capacitance formed by the insulator is reduced. As a result, the current flowing from the parasitic capacitance C to the G N D increases, and the parasitic capacitance C consumes power. Since the parasitic capacitance C has the resistance component R, the current and power flowing on the downstream side (S side, N side, and E side) are reduced. 2Ie = Iw-2*Ic (However, I c : current flowing in the parasitic capacitance) I-----^——^ (Please read the notes on the back and fill out this page) P e P w — 2 氺 c

氺R is ordered by the Intellectual Property Office of the Ministry of Economic Affairs, and is printed by the Consumer Cooperatives (However, P: the power of each pole side, R c : the resistance of the parasitic capacitance). At this time, the inductive reactance (L ω j ) also increases, so The transmission of current from the upstream side (W side) to the downstream side (E side) is hindered. Therefore, the current flowing on the E side (output side) is smaller than the current on the W side. As a result, the current I e flowing on the E side becomes smaller than the current Iw supplied on the W side (i.e., Iw > In = Is > Ie). Therefore, the electric field formed at each pole is relatively strong on the W side and weaker on the E side (i.e., Ew > En II Es > Ee). In this way, in particular, the parasitic capacitance C of the insulator acts as a filter, so that the Chinese National Standard (CNS) A4 specification (210×297 mm) is applied to the paper scale by feeding only the W side of the upper ring electrode to the electrical contact. ) -32- 1250550 A7 B7 V. INSTRUCTIONS (3〇) The W side can generate a relatively strong electric field relative to the E side. The plasma processing apparatus having the above-described configuration is described as an example in which the uranium etching treatment is performed on the oxide film (S i 〇 2 ) of the sand wafer 8 as an example. First, after the wafer 8 is placed on the electrostatic chuck 1 10, the processing chamber 102 is gradually depressurized by a vacuum extraction mechanism (not shown). Thereafter, after a predetermined degree of pressure reduction, a processing gas (for example, C 4 F 8 gas, C 〇 gas, ar gas, 〇 2 gas) is supplied from the processing gas supply source (not shown) to the processing chamber 1 0 2, It is maintained at a set pressure of, for example, 40 m T 〇rr. Then, for example, a high frequency power of 13.56 MHz and 1500 W is applied from the second high frequency power source 1 16 to the lower electrode 1 0 8 . Further, for example, a high frequency power of 100 MHz, 300 W is applied from the first high frequency power source 13 2 to the W side of the upper ring electrode 1 2 4 to the electric contact 1 3 4 so that the plasma is excited to the processing chamber 1 0 2 Inside. The electric field between the two electrodes 1 0 8, 1 2 0 and the magnetic field perpendicular to the electric field form electromagnetic fields that are orthogonal to each other in the plasma field. At this time, as described above, the magnetic field formed in the processing chamber 1 〇 2 by the magnet 138 is formed by a lower magnetic field density on the W side than on the E side. Also, the distance between the electrodes was set at 2 7 m m. Further, when a voltage is applied to the lower electrode 1 0 8 on which the semiconductor wafer 8 is placed by the second high-frequency power source 116, the electrons in the plasma are prioritized over the ion particles, and the wafer 8 becomes charged negatively. Self-biased bias. Thus, a large potential difference is generated between the plasma voltage and the self-bias bias of the wafer 8, and the Chinese National Standard (CNS) A4 specification (210X297) is applied to the paper size. I-------- -I (Please read the note on the back and then fill out this page) Book 4 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed -33- 1250550 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed A7 B7 V. Invention Description (31) A field of sheathing is formed between the slurry field and the surface of the wafer 8. In the present embodiment, as described above, when the voltage is applied only to the W-side feeding contact 1 3 4 of the upper ring electrode 1 24, the field of the screen acts as the parasitic capacitance C of the upper electrode 120. On the N side, the S side and the E side form a relatively weak electric field, and a strong electric field is formed on the W side. Thus, on the W side, a relatively strong electric field is formed relatively for a relatively weak magnetic field. With such an electromagnetic field, the electrons and ion particles in the plasma inductively induce the E X B drift motion, and perform a cycloid motion in the elliptical region between the electrodes to form a uniform and high-density plasma. Thus, the ions in the plasma fly through the sheath field at a high speed by their potential differences, and vertically collide with the surface of the semiconductor wafer 8. Thereby, reactive ion etching is performed along with the photoresist pattern formed on the surface of the semiconductor wafer 8. At this time, the generated gas generated by the etching is discharged to the outside through the discharge port 136. Further, in the above-described embodiment, the plasma processing apparatus is configured as a device for ruthenium oxide film on the surface of a semiconductor wafer on which uranium is engraved, and other objects such as an LCD substrate may be used as the object to be processed. Other etching processes can be implemented. Further, in the above embodiment, an example in which the plasma processing apparatus is configured as an etching apparatus will be described, but other plasma processing apparatuses such as an ashing apparatus, a sputtering apparatus, or a C VD apparatus may be constructed. Further, in the above-described embodiment, the case where the upper ring electrode is configured as a ring electrode having a single structure is described. However, a ring electrode having a multiple structure in which a plurality of ring electrodes are arranged concentrically may be formed. At this time, for each ring electrode, the paper size is applicable to the Chinese National Standard (CNS) Α4 specification (210Χ297 mm) 丨^装---1 ϋϋ ·ϋϋ ϋ_1_^—^τ1>ϋ ϋϋ· · (Please read the back first Note: Please fill out this page again.) 4 -34- 1250550 A7 B7 V. INSTRUCTIONS (32) Do not give electricity to the proper position, and it can also improve the drift effect more effectively. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a longitudinal sectional view showing a plasma processing apparatus according to a first embodiment of the present invention. Fig. 2 is a view showing an isoelectric circuit of the focus ring shown in Fig. 1. Fig. 3 is a graph showing the etch rate distribution in the radial direction of the wafer in the case where the material of the focus ring is subjected to various etching treatments in the plasma processing apparatus shown in Fig. 1 . Fig. 4 is a circuit diagram showing the relationship between the wafer on the lower electrode of the plasma processing apparatus of Fig. 1 and the relationship between the focus ring and the sheath. Fig. 5 is a graph showing the relationship between the impedance of each material and the dielectric constant and the uniformity of the etching rate when the material of the focus ring is changed. Fig. 6 is a view showing a second embodiment of the present invention, and is an enlarged view of a shadow ring of the upper electrode shown in Fig. 1. Fig. 7 is a view showing a modification of the upper electrode shown in Fig. 6. Fig. 8 is a schematic longitudinal cross-sectional view showing the configuration of the uranium-etched wafer according to the types of (a) to (f) in the second embodiment. Fig. 9 is a graph showing the uranium engraving rate of the photoresist film when the ruthenium oxide film is etched by etching the mask ring of Fig. 6 with yttrium oxide and changing the interval between the upper and lower electrodes. Figure 10 shows the coverage of the paper with the polyimide film in Figure 6 for the Chinese National Standard (CNS) A4 specification (210X297 mm) - (Please read the back note and fill out this page) Order d Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed -35 - 1250550 A7 B7 V. INSTRUCTIONS (33) The same chart as in Figure 9 when obscuring the ring. Fig. 1 is a cross-sectional view showing the plasma processing apparatus according to the third embodiment of the present invention, taken along the W-pole direction of the magnetic field. Fig. 12 is a plan view showing the configuration of the upper electrode of the plasma processing apparatus shown in Fig. 11. Fig. 13 is a view showing the measurement result of the magnetic field distribution formed on the wafer in the plasma processing apparatus shown in Fig. 1 . Fig. 14 is a view for explaining the principle of forming an electric field by the upper electrode of the third embodiment. Fig. 15 is a view showing a configuration of an example of a conventional plasma processing apparatus. Fig. 16 is a graph showing the etching rate of the photoresist film when the ruthenium oxide film is treated by uranium etching using the plasma processing apparatus shown in Fig. 15. Fig. 17 is a plan view showing the configuration of the upper electrode of the conventional plasma processing apparatus. Main component comparison table 1, 1 2, 1 0 8 : lower electrode 2, 13, 120: upper electrode 3, 14, 132: first high-frequency power source 4, 15, 116: second high-frequency power source, 5, 17, 112: Focus ring, 6, 2 1 , 1 2 1 ·· Shadow ring This paper scale applies to China National Standard (CNS) A4 specification (210X 297 mm) I---------0 batch 丨丨(Please read the note on the back and then fill out this page) Book 4 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed -36 - 1250550 A7 B7 Ministry of Economic Affairs Intellectual Property Bureau Staff Consumer Cooperative Printed V. Invention Description (34) 8 : Wafer 1 〇, 100: electric paddle processing apparatus 1 1 , 1 0 4 : processing container 1 8 , 1 1 〇 : electrostatic chuck 1 9 : cooling mechanism 2 1 A : flange portion 2 1 B : plasma resistant film 1 0 2 : Processing chamber (plasma processing chamber) 1 0 6 , 1 2 8 : Grounding wire 1 1 4 : Second matching device 1 2 2 : Upper central electrode 1 2 4 : Upper ring electrode 1 2 6 : Upper focusing Ring 1 3 0 : First matcher 1 3 4 : Feed contact 1 3 6 : Exhaust pipe 1 3 8 · Magnet 1 4 0 a 1 4 0 b : Insulator C : Parasitic capacitance (please read the back note first) Matters fill in this page again) , Installed · d booked this paper scale applicable Chinese National Standard (CNS) A4 size (210X297 mm) -37-

Claims (1)

8 8 8 8 ABCD Patent Application No. 90 1 3221 3 Patent Application Revision of Chinese Patent Application Amendment 1 April 1st, 1992. 1. A plasma processing method is provided with a pair of electrodes arranged in parallel with each other in a processing container. 'In the plasma processing apparatus in which the electrode is held on the electrode of either side while the electrode is provided with a focus ring surrounding the object to be processed, at least one of the electrodes is applied with high frequency power, and between the pair of electrodes A plasma processing method for treating a processed object by the plasma, characterized in that: (a) a plasma processing process under a certain processing condition using the above-mentioned focus ring of a certain material, size and shape And (b) according to the result of the plasma treatment, when the treatment rate on the outer peripheral side of the object to be treated (b-1) is lower than the treatment rate on the center side, the impedance of the focus ring is increased and / or medium constant, Ministry of Economic Affairs, Intellectual Property Bureau, employee consumption cooperative printing _ swallow, whether the case after the change of the case of Mo Shihe guilty (please read the note on the back and then fill out this page) (b - 2) was When the processing rate on the outer peripheral side of the physical body is higher than the processing rate on the center side, the impedance of the focus ring and/or the dielectric constant are lowered as the degree is lower, and at least one new focus ring of the material, size, and shape is prepared. The process, and (c) the use of the newly prepared focus on the process of plasma treatment under the processing conditions of the above (a) process. · 2. For the plasma treatment method described in the scope of patent application, the paper scale applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) 1250550 A8 B8 C8 D8 VI. Patent application scope 2 (please first In the case of reading the back of the note, the focus ring has a rectangular cross-sectional shape; in the above (b } _, it is prepared to change the projected area and/or length of the axis direction _. Focus, ring 3. The plasma processing method according to claim 1, wherein the material of the focus ring is a composite material comprising a plurality of materials. 4 · The plasma according to claim 3 In the treatment method, #, the material of the focus ring is a composite material comprising a composite material comprising an oxide cone, a composite material comprising tin nitride, and a composite material selected from the group consisting of carbonized sand. The plasma processing method according to the first aspect of the invention, wherein the plasma film is etched as a plasma treatment. The plasma processing device is characterized in that: a processing container is provided, and a processing container is provided. a first electrode in the processing container, and a second electrode disposed in the processing container in parallel with the first electrode to hold the object to be processed, and the Ministry of Economy, Intellectual Property Office, and the Consumer Cooperative, printed on the first electrode a high frequency power source to which at least high frequency power is applied, and a shadow ring formed of an inorganic oxide covering an outer peripheral portion of the first electrode opposite to the second electrode; and high frequency power applied by the high frequency power source A plasma is generated between the first and second electrodes, and the plasma is configured to process the object to be processed, and the portion in contact with the plasma of the shielding ring is covered with a plasma resistant film. A plasma processing device belonging to the paper with a photoresist film covering the Chinese National Standard (CNS) A4 specification (210X297 mm) - 2 - 1250550 A8 B8 C8 D8 VI. Patent application scope 3 (please read first) Precautions on the back side. Fill in the page. The processed object of the film is used for plasma treatment of the above-mentioned film etching process in accordance with the shape of the above-mentioned photoresist film. The device includes a processing container, a first electrode disposed in the processing container, and a second electrode disposed in the processing container in parallel with the first electrode to hold the object to be processed, and a high frequency power source for applying at least high frequency power to one electrode, and a shadow ring formed of an inorganic oxide covering a peripheral portion of the first electrode opposite to the second electrode; and the high frequency power supply is applied In the frequency power, a plasma is generated between the first and second electrodes, and the plasma is configured to be etched by the object to be processed, and at the same time, the portion in contact with the plasma of the shadow ring is covered with a plasma resistant film. . The plasma processing apparatus according to the sixth aspect of the invention, wherein the plasma resistant film is composed of an oxide of a rare earth element or a heat resistant resin. Printed by the Intellectual Property Office of the Ministry of Economic Affairs, Employees' Consumer Cooperatives. 9. The plasma processing apparatus according to Item 8 of the patent application, wherein the above-mentioned rare earth element is a leader. The plasma processing apparatus according to claim 8, wherein the heat resistant resin is a polyimide resin. 1 1 . A plasma processing apparatus, characterized in that: a processing container is provided, and a central paper sheet disposed in the processing container and electrically grounded is applicable to the Chinese National Standard (CNS) A4 specification (210X297) PCT) -3- 1250550 A8 B8 C8 D8 Printed by the Intellectual Property Office of the Ministry of Economic Affairs, Employees' Consumer Cooperatives. VI. Patent Application No. 4 Electrode' and the first electrode surrounding the high frequency electrode around the central electrode, and in the above processing container Arranging in parallel with the first electrode to hold the second electrode having the object to be processed, and forming a directionality with respect to the processed surface of the object to be processed between the first and second electrodes a magnetic field applying mechanism of the magnetic field, and a local frequency power source for applying a local frequency power to at least the frequency-frequency electrode of the first electrode; the power supply from the high-frequency power source to the high-frequency electrode is only the magnetic field of the high-frequency electrode The power supply contact on the west side. The plasma processing apparatus of the invention of claim 1 is further provided with a focus ring that is electrically grounded around the outer periphery of the high-frequency electrode of the first electrode. The plasma processing apparatus according to claim 12, further comprising: an insulating member interposed between the center electrode and the high-frequency electrode of the first electrode; An insulating member between the high frequency electrode of one electrode and the above-described focus ring. The plasma processing apparatus of the invention of claim 1 wherein the high frequency power constituting the plasma generation and the bias voltage is applied to the second electrode. 1 5 · A plasma processing device featuring: a processing container, and the paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) (please read the back note before completing this page) -4- 1250550 as B8 C8 D8 VI. Patent Application No. 5 (Please read the note on the back side and fill in this page) The first electrode disposed in the processing container and the first electrode are disposed in parallel with the first electrode. a second electrode that holds the object to be processed in the container, a high-frequency power source that applies at least high-frequency power to the second electrode, and a focus ring that is disposed on the second electrode around the object to be processed; In the electric power, plasma is generated between the first and second electrodes, and the plasma is configured to process the object to be processed, and the impedance ring is sealed by applying the high-frequency power to the plasma. It is made of any material of 2 5 Ω, a dielectric material having a dielectric constant of 2 1 to 30, and a dielectric material having an impedance of 12 to 25 Ω and a dielectric constant of 5 to 30. The plasma processing apparatus of claim 15, wherein the focus ring is a composite material comprising a plurality of materials, and the manufacturer of the Ministry of Economic Affairs, the Intellectual Property Office, the employee consumption cooperative, prints. The plasma processing apparatus of the above aspect, wherein the focus ring is composed of an oxidation pin, an aluminum nitride, a composite material comprising zirconia, a composite material containing aluminum nitride, and a composite comprising chromium oxide and tantalum carbide. A material, a composite material comprising aluminum nitride and tantalum carbide, a joint of ruthenium oxide and aluminum nitride, and a combination of two or more of the composite materials. 1 8 The plasma processing apparatus according to the fifteenth aspect of the invention, wherein the high frequency electric power of 6 ΟΜΗ z is applied to the first electrode and the high frequency electric power of 2 MHz is applied to the above. Two electrodes. ' The plasma processing apparatus according to claim 15, wherein the plasma treatment of the sand oxide film formed on the object to be processed is performed as the plasma treatment. By. (Please read the notes on the back and fill out this page), 1T Ministry of Economic Affairs, Intellectual Property Bureau, Staff Consumer Cooperatives Print This paper scale applies to China National Standard (CNS) Α4 specifications (210Χ297 mm) -6-