JPH11162694A - Component for discharge and plasma device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a component for discharging capable of forming a stable plasma and enabling miniaturization, and a plasma device using it. SOLUTION: A component 16 for discharging is equipped with a cylindrical, tubular, or plate-shaped dielectric member 28 made of dielectric material and an electroconductive thin film 30 formed to have a predetermined pattern on an outer surface of the dielectric member 28. By this constitution, an antenna, an electrode, or the like can be integrated with the dielectric member 28. A coil-antenna-like pattern 30c can be used as the pattern of the thin film. When high-frequency power is applied to the thin film, an electromagnetic field is inducted, via the dielectric member 28, to form a plasma in a reduced-pressure space inside the component for discharging. Because there is no air between the thin film and the dielectric member, a stable plasma can be formed without being affected by the environment such as temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma device used in a manufacturing process of a macroelectronic device such as a semiconductor integrated circuit device and a liquid crystal display device, and a discharge component which is a main component thereof.

[0002]

2. Description of the Related Art In order to improve the performance of macroelectronic devices such as semiconductor integrated circuit elements and liquid crystal display elements and to reduce costs, high-precision and high-speed microfabrication (dry etching, etc.) that can withstand large-scale integration is required. There is an increasing demand for realizing an area on a substrate to be processed. Processing using high-density plasma is suitable for such fine processing.
Techniques for forming such high-density plasma include an inductively coupled system (Inductively Coupled System), a capacitively coupled system (Capacitive Coupled System), and a helicon system (Helic).
on System), ECR (Electron Cyclotron Resona)
nce System: electron cyclotron resonance method).

[0003] In any of these plasma forming systems, high-frequency power is applied to a metal coil antenna or an electrode attached to the outside of the depressurized container at a fixed interval, and a dielectric material constituting a wall surface of the depressurized container is applied. It has a common feature that a high-frequency electric field or an electromagnetic field is induced in a container through a window to form plasma.

[0004]

In recent years, silicon wafers and liquid crystal substrates, which are objects of plasma processing, have a remarkable tendency to increase in size. Along with this, components such as a decompression container, a dielectric window, and a coil antenna used for processing must be increased in size. As a result, there is a problem that the system including the components, their adjustment mechanism, the transport mechanism, and the like must be enlarged, and the cost of a clean room to be installed increases.

[0005] Further, since the coil antenna or the electrode is held apart from the dielectric window, holding means for that purpose is required, and this also contributes to an increase in the size of the apparatus and equipment.

Further, the state of air existing between the coil antenna and the dielectric window, for example, the state of plasma generated in the depressurized vessel due to temperature, humidity, etc. changes, making it difficult to maintain plasma stably. there were.

There is another problem that the reproducibility of plasma cannot be maintained unless the interval between the coil antenna and the dielectric window is finely adjusted every time the part is replaced.

An object of the present invention is to provide a discharge component capable of solving the above-mentioned various problems in the related art and a plasma device using the same.

[0009]

To achieve the above object, the present invention provides a cylindrical, tubular or plate-shaped dielectric member made of a dielectric material, and a predetermined pattern formed on the outer surface of the dielectric member. A discharge component comprising the formed conductive thin film is characterized. With this configuration, it is possible to integrally handle the dielectric member and the antenna or the electrode.

[0010] The pattern of the thin film may be a coil antenna-like pattern. In such a case, when high-frequency power is applied to the thin film, an electromagnetic field is induced in the reduced-pressure space inside the discharge component via the dielectric member, and plasma is formed. When a thin film is formed in an electrically divided pattern so as to form at least one pair of electrodes, when high-frequency power is applied to the electrode portion, a high-frequency electric field is induced in a reduced-pressure space inside the discharge component, and Generates a plasma. Since no air exists between the coil antenna or the thin film as an electrode and the dielectric member, stable plasma can be formed without being affected by the temperature of the surrounding environment.

Further, by arranging a magnet for applying a magnetic field around, a higher density plasma is formed by the interaction between the magnetic field and the electric field or the electromagnetic field.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows an inductively coupled plasma type etching apparatus which is a plasma apparatus according to a first embodiment of the present invention. The etching apparatus 10 includes a reaction vessel (decompression vessel) 12 whose inside is decompressed. Reaction vessel 1
Numeral 2 includes a cylindrical container side wall 14 made of a metal material such as stainless steel, and a lid 16 as a hemispherical plate-shaped discharge component according to the present invention mounted on an upper portion thereof.

A susceptor 18 on which a silicon wafer W to be processed is placed is disposed inside the reaction vessel 12. On the upper surface of the susceptor 18, an electrostatic chuck 20 for fixing the silicon wafer W is provided. The susceptor 18 also functions as an electrode, and is grounded via a high frequency bias power supply 22. Therefore, when a high frequency bias voltage of, for example, 13.56 MHz is applied to the grounded container side wall 14, the susceptor 18 functions as a cathode and the container side wall 14 functions as an anode.

The reaction vessel 12 is provided with a gas supply port 24 for introducing an etching gas supplied from a gas supply source (not shown) into the inside, and further for exhausting the inside. An exhaust port 26 connected to a vacuum pump (not shown) is provided.

The lid 16 which is a part of the reaction vessel 12 is composed of a hemispherical plate-shaped main body (dielectric member) 28 and a conductive thin film 30 formed on its outer surface in a predetermined pattern. .

The main body 28 is a solid body made of a dielectric material such as alumina, quartz, silicon carbide and silicon nitride. 10 mTorr inside the reaction vessel 12
Since the pressure is reduced to the extent, the main body 28 preferably has a thickness of about 20 mm in terms of strength.

The thin film 30 on the outer surface of the main body 28 is made of a conductive material such as copper or aluminum. As clearly shown in FIG.
The thin film 30 has a lower portion 30a formed in an annular shape on the lower outer peripheral surface of the main body 28, and an upper portion 30b formed in a dish shape on the top of the main body 28. The thin film 30
Has a plurality of spiral portions 30c extending spirally between the lower portion 30a and the upper portion 30b. A high frequency power supply 34 is connected between a lower portion 30a and an upper portion 30b of the thin film 30 via a matching device 32.

The thin film 30 is bonded to the main body 28 with a suitable adhesive.
May be directly adhered to the outer surface of the substrate, but in order to increase the manufacturing accuracy, it is preferable to deposit and form by a known thin film forming technique including a series of processes such as sputtering, masking and etching. In this case, if a metal such as copper or aluminum is directly deposited on the main body 28 made of a dielectric material, the metal thin film is easily peeled off. Therefore, it is effective to form titanium nitride or the like as the lower layer film.

In such a configuration, for example,
After reducing the pressure to about 0 mTorr, an etching gas is introduced, and a high frequency of 13.56 MHz, for example, is applied between the upper thin film portion 30b and the lower thin film portion 30a. The spiral thin film portion 30c functions as a coil antenna, and An electromagnetic field is induced inside the reaction vessel 12 through the main body 28 of the above, and plasma is generated. Further, energy is supplied to the electrons in the plasma, and the plasma is maintained at a high density. In the configuration of the present invention, there is no gap between the spiral thin film portion 30c as the coil antenna and the main body 28, and the plasma is formed and maintained with a constant reproducibility without being affected by the temperature, humidity, etc. of the air. It is possible to do.
When a high-frequency bias voltage is applied between the container side wall 14 and the susceptor 18 under such stable plasma, the etching reaction of the silicon wafer W on the susceptor 18 is performed stably.

Since the main body 28 and the coil antenna 30 are not separate from each other, the lid 16 can be easily cooled as a whole. Therefore, although not shown, when the entire lid 16 is cooled by the cooling device, more stable plasma can be formed. As the cooling device, a device having a structure in which the surface of the lid 16 is covered with a suitable insulating material having an insulating property, the surface thereof is surrounded by a water jacket, and cooling water is circulated in the water jacket can be considered.

Further, since the thin film 30 as a coil antenna is directly supported by the main body 28, no special antenna holding mechanism is required, and the whole apparatus can be made compact.

FIG. 3 shows a second embodiment of the present invention. The plasma device in the second embodiment is a dielectrically coupled plasma type sputtering device 40. The sputtering apparatus 40 is provided with a container side wall 4 constituting a vacuum container 42.
4, a target 46 attached to an upper opening of the container side wall 44, and a wafer supporting pedestal 48 arranged inside the container 42. A negative terminal of a DC power supply 50 is connected to the target 46, and a high-frequency power supply 52 is connected to the pedestal 48. In addition, the reaction vessel 4
2 includes a gas supply source (not shown) for supplying a processing gas, and a vacuum pump (not shown) for reducing the pressure inside.
And are connected.

The vessel side wall 44 constituting the reaction vessel 42 is a discharge part according to the present invention, and as shown in FIG. 4, a cylindrical main body (dielectric member) 54 made of a dielectric material and formed on the outer surface thereof. And a conductive thin film 56. The thin film 56 includes an upper portion 56a and a lower portion 56b formed in an annular shape on each of an upper outer peripheral surface and a lower outer peripheral surface of the main body 54, and a single spiral portion 56c spirally extending between these portions 56a and 56b. And Regarding the material and forming method of the main body 54 and the thin film 56,
This is the same as the embodiment.

In the case of depositing titanium or the like on the surface of the silicon wafer W in the sputtering apparatus 40 having the above-described structure, first, after reducing the pressure to about 1 Torr, a processing gas is introduced, and the upper portion 56a and the lower portion 56 of the thin film 56 are introduced.
When a high frequency of, for example, 2.0 MHz is applied to the reaction container 42 via the matching unit 58 by the high frequency power supply 60 via the matching unit 58, the spiral portion 56c of the thin film 56 functions as a coil antenna as in the first embodiment, and the reaction vessel 42 A stable plasma is formed and maintained inside the device. Then, the high frequency power supply 52 and the DC power supply 50 are turned on, and the target 46 and the pedestal 4 are turned on.
When a high frequency bias power is applied between the target 4 and the target 4, the positive ions in the plasma collide with the target 46,
Atoms are ejected from 6 and deposited on the silicon wafer surface on pedestal 48.

The first and second embodiments both relate to an inductively coupled plasma apparatus, and a part of the reaction vessel functions as a discharge component. However, the present invention is limited to these embodiments. It is not something to be done.

For example, FIG. 5 shows an etching apparatus 60 of the type in which a plasma flow is sent from a plasma flow generator connected to a reaction vessel into the interior of the vessel, wherein a plasma flow generator 62 is constructed in accordance with the present invention. A discharge component of a capacitive coupling type can be applied. As clearly shown in FIG. 6, the discharge component 64 of the capacitive coupling type according to the present invention is used.
Is composed of a tube (dielectric member) 66 serving as a gas flow path and a conductive thin film 68 formed on the surface of the tube 66. The tube 66 is made of a dielectric material such as alumina, and the thin film 68 is formed by bonding or depositing a conductive material such as copper or aluminum. Thin film 6
Reference numeral 8 denotes an upper portion 68a and a lower portion 68b which are formed annularly on the upper outer peripheral surface and the lower outer peripheral surface of the tube 66, respectively.
It has. This thin film 68 is different from the above-described dielectric coupling type, in that a first pair of electrodes 68c connected to the upper portion 68a is used to generate a plasma by capacitively introducing a high frequency into the inside of the tube. And a second pair of electrodes 68d connected to the lower portion 68b. As can be understood from FIG. 7, each pair of electrodes 68c, 68c; 68d, 68d
Are opposed to each other, and the first pair of electrodes 68
c and the second pair of electrodes 68d are electrically divided.

In such a configuration, when the pressure inside the reaction vessel 70 is reduced, the pressure inside the tube 66 is also reduced. Then, for example, 13.5 between the upper electrode 68a and the lower electrode 68b of the thin film 68 by the high frequency power supply 74 via the matching unit 72.
When a high-frequency electric power of 6 MHz is applied, a high-frequency electric field is induced in the tube 66, and high-frequency energy is supplied to a gas flowing therethrough to be a plasma flow, which is sent to the silicon wafer W on the susceptor 76.

As the discharge component 64 used in the plasma flow generator 62, in addition to the capacitive coupling method, an inductive coupling method, a helicon wave method, and an ECR method can be configured according to the present invention.

FIG. 8 shows a discharge component 80 of the inductive coupling type, which is the same as the components shown in FIGS. 3 and 4 except that the container side wall is replaced by a tube 82. Therefore, the description of the operation is omitted.

The configuration shown in FIG. 9 is a helicon wave type discharge component 90. A conductive thin film 94 formed on the outer surface of a tube 92 made of a dielectric material is formed in the same manner as in the inductive coupling type.
It constitutes a coil antenna. However, in the illustrated embodiment, the upper portion 94a and the lower portion 9 of the thin film 94 are provided.
4b, which is an expanded view of FIG.
As is apparent from FIG. Also,
In the helicon wave type discharge component 90, a magnet assembly 98 having a pair of upper and lower cylindrical magnets 96 is arranged so as to surround a tube 92.

In this configuration, the upper portion 94a of the thin film 94
When a high-frequency power is applied between the antenna and the lower portion 94b, an electromagnetic wave induced from the rectangular thin film portion 94c as an antenna propagates a magnetic field formed in the tube 92 by the magnet 96, and the helicon wave and the electron , A high-density plasma is formed.

In the prior art, since the antenna is arranged at a predetermined interval outside the tube, the structure for supporting the magnet assembly and the antenna is complicated, and the size tends to be large. However, in the configuration of the present invention, since the antenna portion is integrated with the tubular body, the above-described conventional problem is avoided.

FIG. 11 shows an ECR type discharging component 100.
Is shown. The structure of the discharge component 100 with respect to the tube 102 and the thin film 104 is substantially the same as that of the capacitive coupling type shown in FIG. The difference from FIG. 6 is that a magnet assembly 106 is provided outside the tube 102. The tube assembly 102 is formed by the magnet assembly 106.
The high frequency supplied from the electrode portion of the thin film 102 causes electron cyclone resonance due to the magnetic field formed therein, and higher density plasma is formed. Also in this configuration, conventionally, the separately provided electrode is integrated with the tube, so that downsizing, manufacturing, and the like can be facilitated.

As understood from the above, the present invention can be embodied in various modes. For example, FIGS.
The configuration shown in FIG. 1 is replaced with the apparatus shown in FIG.
It is also possible to apply to the device.

Since the conductive thin film can be formed on the wall surface of the dielectric member by a deposition technique, the dimensions and the like can be flexibly changed. For example, in the conventional configuration using a coil antenna made of a conducting wire, there is a certain limit to miniaturization of the discharge component, but the configuration of the present invention makes it possible to manufacture an extremely small device.
In the configuration shown in FIGS. 6 to 11, the thickness of the pipe is 3 to 10 m.
m and a length of 7 to 8 cm. Such a miniaturized product can be used in various applications, such as being easily installed in a concave portion in a reaction vessel that is difficult to clean by a normal plasma cleaning process. This ease of installation also depends on the configuration in which the antenna and the wall are integrated.

When the thickness is small, the capacitance of the dielectric becomes small, so that the frequency of the applied high frequency is 13.5.
It is effective to set it to 6 MHz or more.

[0038]

As described above, according to the present invention, since a conductive thin film is used for a member functioning as an antenna portion or an electrode portion in a discharge component and is adhered to a dielectric member, the discharge component itself is formed. Further, the size of the plasma device using the same can be reduced. In addition, the integration also has the effect of significantly reducing the labor for manufacturing, assembling, adjusting, and the like.

Further, since there is no gap between the conductive thin film and the dielectric portion, stable plasma can be formed without being affected by the temperature and humidity of air. Therefore,
The plasma can be easily controlled, a stable process can always be performed, and the performance of the manufactured macroelectronic device can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an etching apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a lid as a discharge component used in the etching apparatus of FIG. 1;

FIG. 3 is a schematic view showing a sputtering apparatus according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing a container side wall as a discharge component used in the sputtering apparatus of FIG. 3;

FIG. 5 is a schematic view showing an etching apparatus according to a third embodiment of the present invention.

FIG. 6 is a perspective view showing a capacitively coupled discharge component used in the etching apparatus of FIG. 5;

FIG. 7 is a sectional view taken along line VII-VII in FIG. 5;

FIG. 8 is a perspective view showing a discharge component of a dielectric coupling system applicable to the etching apparatus of FIG. 5;

FIG. 9 is a perspective view showing a helicon wave type discharge component applicable to the etching apparatus of FIG. 5;

FIG. 10 is a developed view showing a thin film pattern of the discharge component of FIG. 9;

FIG. 11 is a perspective view showing an ECR type discharge component applicable to the etching apparatus of FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Etching apparatus (plasma apparatus), 12 ... Reaction vessel (decompression vessel), 14 ... Container side wall, 16 ... Lid (parts for discharge), 18 ... Susceptor, 24 ... Gas supply port, 26 ... Exhaust port, 28 ... Main body (derivative member), 30 conductive thin film,
32: Matching device, 34: High-frequency power source, 40: Sputtering device (plasma device), 42: Reaction container (decompression container), 44: Container side wall (discharge part), 46: Target, 54: Main body (dielectric member) , 56 ... conductive thin film, 6
0: etching apparatus (plasma apparatus), 62: plasma flow generator, 64, 80, 90, 100: discharge parts,
66, 82, 92, 102 ... tubular body (dielectric member), 6
8, 94, 104: conductive thin film, 96: magnet, 98, 1
06: Magnet assembly.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Keiji Horioka 14-3 Shinizumi, Narita City, Chiba Pref. Nogedaira Industrial Park Applied Materials Japan Co., Ltd.

Claims (14)

[Claims] 1. A discharge component, comprising: a dielectric member made of a dielectric material; and a conductive thin film formed on an outer surface of the dielectric member in a predetermined pattern. 2. The discharge component according to claim 1, wherein the pattern is a coil antenna-shaped pattern. 3. The discharge component according to claim 1, wherein the pattern is a pattern that is electrically divided so as to form at least one pair of electrodes. 4. The discharge component according to claim 1, wherein the thin film is formed on the dielectric member by bonding. 5. The discharge component according to claim 1, wherein the thin film is formed on the dielectric member by a deposition technique. 6. The discharge component according to claim 1, wherein a magnet is provided outside the dielectric member. 7. A decompression container for accommodating an object to be processed, a unit for introducing a processing gas into the decompression container, an exhaust unit for depressurizing the interior of the decompression container, and a discharge component for forming plasma in the decompression container. A discharge device, wherein the discharge component is formed in a predetermined pattern on an outer surface of the dielectric member, the dielectric member being made of a dielectric material constituting at least a part of the decompression container, and a high frequency is formed. And a conductive thin film to which electric power is applied. 8. A decompression container for accommodating an object to be processed, a unit for introducing a processing gas into the decompression container, an exhaust unit for depressurizing the interior of the decompression container, and a discharge component for forming a plasma in the decompression container. A discharge device, wherein the discharge component is formed in a predetermined pattern on an outer surface of the dielectric member, the dielectric member being made of a dielectric material connected to the decompression container, and high frequency power is applied. And a conductive thin film to be formed. 9. The plasma device according to claim 7, wherein the pattern is a coil antenna-shaped pattern. 10. The plasma apparatus according to claim 7, wherein the pattern is a pattern that is electrically divided so as to form at least one pair of electrodes. 11. The plasma apparatus according to claim 7, wherein the thin film is formed on the dielectric member by bonding. 12. The semiconductor device according to claim 7, wherein said thin film is formed on said dielectric member by a deposition technique.
0. The plasma apparatus according to any one of 0. 13. The plasma apparatus according to claim 7, wherein a magnet is provided outside the dielectric member. 14. The plasma apparatus according to claim 7, further comprising means for cooling said discharge component.