JP5954195B2 - Substrate processing apparatus, substrate processing method, and storage medium - Google Patents

Description

  The present invention relates to a technique for processing a substrate using a chemical solution containing ammonia.

  Substrate for removing dust, natural oxides, etc. by supplying various chemicals to the rotating wafer in the manufacturing process of a semiconductor device in which a laminated structure of integrated circuits is formed on the surface of a semiconductor wafer (hereinafter referred to as wafer). Processing devices are known.

  In this type of processing, chemical liquid is scattered around the rotating wafer, and mist or vapor of chemical liquid components is generated, which may contaminate the wafer by adhering to the wafer. Therefore, a member for receiving liquid (hereinafter referred to as a cup) is arranged around the substrate holding unit for holding the substrate, or the clean air or inert gas is down-flowed in the casing in which these substrate holding unit and cup are arranged. The atmosphere in which the wafer is processed is maintained in a clean state (for example, cited document 1).

JP 2007-173308 A: Paragraph 0025, FIG.

  There may be a case where a gas retention portion is formed in the housing. When ammonia that is lighter than air is used, ammonia mist diffuses in the casing and accumulates in a gas retention portion or the like above the wafer. If this ammonia is attached to the surface of the wafer in a downflow flow or the like, the wafer may be contaminated.

  This invention is made | formed in view of such a situation, and the objective is to suppress adhesion of ammonia to a board | substrate when processing a board | substrate using the chemical | medical solution containing ammonia.

A substrate processing apparatus according to the present invention is disposed in a housing, and a substrate holding unit that horizontally holds a substrate;
A chemical nozzle for supplying a chemical solution containing ammonia to the surface of the substrate;
An ammonia absorption part that is provided in the casing and stores an acidic absorbent that absorbs ammonia diffused in the casing;
An absorption liquid supply section for supplying an acidic absorption liquid to the ammonia absorption section ,
The ammonia absorption part is provided at a position higher than the substrate held by the substrate holding part .

The above-described substrate processing apparatus may have the following features.
And supplies a discharge portion for discharging the reservoir liquid in (a) before Symbol ammonia absorption unit, when supplying a chemical solution containing ammonia from the chemical liquid nozzle to the surface of the substrate, the absorption liquid acidic ammonia absorption unit And a control unit that outputs a control signal so as to execute the discharge of the absorption liquid of the ammonia absorption unit from the discharge unit before starting the drying of the substrate.
( B ) a rinsing liquid nozzle for supplying a rinsing liquid for rinsing and cleaning the chemical liquid to the substrate; and a drying liquid nozzle for supplying a drying liquid containing an organic solvent; and the control unit includes the rinsing liquid After the supply of the liquid is stopped, the substrate is dried after supplying the drying liquid from the drying liquid nozzle to the substrate, and before the supply of the drying liquid is started, the ammonia absorption is performed from the discharge unit. To output a control signal so as to carry out the drainage of the absorbent.
( C ) When the chemical nozzle is a first chemical nozzle, the substrate is provided with a second chemical nozzle that supplies another chemical different from the chemical containing ammonia on the surface of the substrate, and the control unit supplies the chemical to the substrate. The supply of the other chemical solution from the second chemical solution nozzle during the period from the supply of the chemical solution containing ammonia and the subsequent supply of the rinse solution to the start of drying of the substrate, and the other A control signal is output so as to execute the supply of the rinsing liquid from the rinsing liquid nozzle instead of the chemical liquid.

(D) The ammonia absorption part is arranged so that a contact region between the acidic absorption liquid and the atmosphere in the housing surrounds the substrate held by the substrate holding part in the circumferential direction when viewed from the upper surface side. Being.
(E) When the chemical nozzle is the first chemical nozzle, the second chemical nozzle that supplies another chemical different from the chemical containing ammonia to the surface of the substrate, and the flow rate of the airflow flowing in the housing A flow rate adjusting unit for adjusting, and during the period in which the chemical liquid containing ammonia is supplied from the first chemical liquid nozzle, it flows in the casing more than the period in which another chemical liquid is supplied from the second chemical liquid nozzle. The said control part which outputs a control signal so that the flow volume of airflow may be increased was provided.
(F) The acidic absorbing solution includes a solution of at least one acid selected from the group consisting of sulfuric acid, hydrochloric acid, and hydrofluoric acid.

  The present invention can absorb ammonia diffused in the casing when using a chemical solution containing ammonia, and can suppress adhesion of ammonia to the substrate.

It is a figure which shows the structure of the substrate processing apparatus which concerns on embodiment of invention. It is the top view which looked at the ammonia absorption part provided in the said substrate processing apparatus from the upper surface side. It is explanatory drawing which shows the processing sequence of the wafer by the said substrate processing apparatus. It is a 1st explanatory view showing an operation of the substrate processing device. It is explanatory drawing which shows the effect | action of an ammonia absorption part. It is the 2nd explanatory view showing an operation of the substrate processing device. It is the 3rd explanatory view showing an operation of the substrate processing device. It is a 4th explanatory view showing an operation of the substrate processing device. It is a figure which shows the structure of the substrate processing apparatus in connection with other embodiment.

  Hereinafter, the configuration of the substrate processing apparatus according to the embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the substrate processing apparatus has a structure in which a wafer holding unit 10 (substrate holding unit) that holds a wafer W in a horizontal posture and a cup unit 30 are provided in a housing 41. The wafer holding unit 10 includes a disk-shaped rotating plate 11 and a plurality of, for example, three holding pins 12 attached to the upper surface of the rotating plate 11. 12 is configured as a mechanical spin chuck that is held by the motor 12. The rotary plate 11 incorporates a lift plate (not shown) having lift pins 13 that support and lift the lower surface of the wafer when the wafer W is transferred to and from an external transfer arm.

  A rotating shaft 14 extending in the vertical direction is provided at the center of the lower surface of the rotating plate 11, and the lower end of the rotating shaft 14 is used for rotating the rotating plate 11 around the vertical axis via the rotating shaft 14. A rotation drive unit 15 made of an electric motor or the like is provided.

  An annular guide ring 21 is attached to the rotary plate 11 via three (only one is shown in FIG. 1) support columns 23. The inner peripheral surface of the guide ring 21 receives a chemical liquid, a rinsing liquid, and a drying liquid (hereinafter collectively referred to as a processing liquid) that are supplied to the rotating wafer W and then shaken off and scattered from the wafer W. Guide into the part 30.

  The cup portion 30 includes an immovable annular first cup 31 located on the outermost side, an annular second cup 32 that can be raised and lowered located on the inner side thereof, and an annular third cup that can be raised and lowered located further on the inner side. A cup 33 and an immovable inner wall 34 located inside the cup 33 are provided. The second cup 32 and the third cup 33 are lifted and lowered by the lifting mechanisms 32A and 33A schematically shown in FIG. A first flow path 311 is formed between the first cup 31 and the second cup 32, a second flow path 321 is formed between the second cup 32 and the third cup 33, and the third cup 33 A third channel 331 is formed between the inner wall 34 and the inner wall 34.

  A cup exhaust port 35 communicating with the first flow path 311, the second flow path 321, and the third flow path 331 is formed on the bottom surface portion of the cup portion 30 (the bottom surface portion of the housing 41). A cup exhaust path 36 is connected to the cup exhaust port 35. The cup exhaust passage 36 is selectively connected to an acidic exhaust line 71, an alkaline exhaust line 72, and an organic exhaust line 73 that form a part of the factory exhaust system via a passage switching valve 701. Since the exhaust lines 71 to 73 are in a negative pressure, the internal space of the cup portion 30 and the internal space of the casing 41 that accommodates the cup portion 30 and the wafer holding portion 10 are exhausted via the cup exhaust port 35. Is done. The cup exhaust passage 36 is provided with a flow rate adjustment valve (not shown), and the exhaust amount from the cup exhaust port 35 can be increased or decreased by adjusting the opening degree. The cup exhaust port 35, the cup exhaust passage 36, and the like correspond to the exhaust part of this example.

  A bent part is provided in the middle of each of the first flow path 311, the second flow path 321 and the third flow path 331, and the gas-liquid mixture flowing through each flow path when the direction is suddenly changed by the bent part. A liquid component is separated from the fluid. The separated liquid component falls into the liquid receiver 312 corresponding to the first flow path 311, the liquid receiver 322 corresponding to the second flow path 321, and the liquid receiver 332 corresponding to the third flow path 331. The liquid receptacles 312, 322, and 332 are connected to the factory's acidic drainage system, alkaline drainage system, and organic drainage system (all not shown) via the corresponding drainage ports 313, 323, and 333, respectively. Has been.

  The substrate processing apparatus further includes a plurality of nozzles 51 to 53 for discharging (supplying) the processing liquid toward the rotating wafer W held by the wafer holding unit 10. In this example, the first nozzle 51 for supplying SC1 (mixed aqueous solution of ammonia water and hydrogen peroxide solution) for removing organic dirt and particles adhering to the surface of the wafer W, and the wafer W A second nozzle 52 for supplying DHF (Diluted HydroFluoric acid) for removing natural oxide on the surface of the liquid and a third nozzle 53 for supplying IPA (IsoPropyl Alcohol) as a drying liquid are provided. ing. Moreover, the 1st nozzle 51 and the 2nd nozzle 52 can also supply DIW (DeIonized Water) which is a rinse liquid for rinse-cleaning these chemical | medical solutions (SC1, DHF).

  These nozzles 51 to 53 are held at the distal end portion of the nozzle arm 54, and a rotation driving portion 55 is provided at the proximal end portion of the nozzle arm 54. By rotating the nozzle arm 54 by the rotation driving unit 55, the nozzle is positioned between the processing position above the center of the wafer W held by the wafer holding unit 10 and the retreat position at the side of the cup unit 30. 51-53 can be moved.

  Here, SC1 corresponds to the “chemical solution containing ammonia” in this example, and the first nozzle 51 corresponds to a chemical solution nozzle (first chemical solution nozzle). The DHF corresponds to “a chemical solution different from the chemical solution containing ammonia”, and the second nozzle 52 corresponds to a second chemical solution nozzle. The first nozzle 51 and the second nozzle 52 are also used as rinse liquid nozzles. Further, the third nozzle 53 is an organic solvent and corresponds to a drying liquid nozzle that supplies IPA that is a drying liquid.

  Each of the nozzles 51 to 53 is connected to a processing liquid supply unit (DIW supply unit 501, SC1 supply unit 502, etc.) provided with a tank of each processing liquid, a flow rate adjusting mechanism, and the like via the processing liquid supply line 56 and the on-off valves V 1 to V 4. DHF supply unit 503 and IPA supply unit 504). For convenience of illustration, in FIGS. 1, 4, and 6 to 8, these processing liquid supply units are illustrated as being connected to the nozzles 51 to 53 through a common processing liquid supply line 56. The first nozzle 51 is supplied to the DIW supply unit 501 and the SC1 supply unit 502, the second nozzle 52 is supplied to the DIW supply unit 501 and the DHF supply unit 503, and the third nozzle 53 is supplied to the IPA supply unit 504, respectively. They are connected via line 56.

  A fan filter unit (FFU) 45 including an air supply fan 452 and a filter unit 453 is provided on the upper surface of the ceiling portion of the housing 41. The FFU 45 can adjust the amount of air supplied to the housing 41 by controlling the air supply fan 452. Further, a rectifying plate 42 having a large number of air supply holes 43 is provided below the ceiling. The rectifying plate 42 is blown downward from the FFU 45, and the clean air spread in the diffusion portion 44 formed between the ceiling portion of the housing 41 and the rectifying plate 42 is uniformly dispersed toward the inside of the housing 41. And supply. Then, the clean air supplied from the air supply holes 43 flows into the cup portion 30 and flows into the cup exhaust port 35 on the bottom surface side of the housing 41, so that the air supply holes 43 enter the wafer W in the housing 41. A downflow of clean air flowing downward is formed. The FFU 45, the air supply hole 43, and the like correspond to the air supply unit of this example.

  Further, the substrate processing apparatus of the present example is provided with an ammonia absorbing portion 61 that stores an ammonia mist that diffuses into the housing 41 and an absorbing solution 63 that absorbs vapor by supplying SC1 to the wafer W. As shown in FIGS. 1 and 2, the ammonia absorbing portion 61 of this example is an elongated bowl-shaped member having a groove 62 formed on the upper surface, and is disposed in an annular shape along the inner wall surface of the housing 41. . The ammonia absorbing portion 61 is disposed below the rectifying plate 42 and above the moving path of the nozzles 51 to 53 that move between the processing position and the retracted position.

  As described above, ammonia that is lighter than air rises in the housing 41 and tends to stay in the vicinity of the inner wall below the rectifying plate 42 where the flow of downflow is relatively weak. Therefore, the ammonia absorbing portion 61 directs the opening portion of the groove portion 62 to a region where ammonia is likely to stay, and the ammonia absorbing liquid 63 is stored in the groove portion 62 so that the ammonia staying in the housing 41 is reduced. Absorb and remove. As shown in FIG. 2 as viewed from the position of aa ′ in FIG. 1, the ammonia absorbing portion 61 has a liquid surface of the absorbing liquid 63 (the absorbing liquid 63 and the atmosphere in the housing 41 and Are arranged so as to surround the wafer W held by the wafer holder 10 in the circumferential direction.

  As the absorbing solution stored in the ammonia absorbing portion 61, an acidic solution that reacts with alkaline ammonia, for example, a solution containing at least one acid selected from the group consisting of sulfuric acid, hydrochloric acid, and hydrofluoric acid is used. In this example, sulfuric acid having a concentration of 0.001 to 0.1% by weight is used.

  The ammonia absorption unit 61 is connected to a sulfuric acid supply unit 505 having a tank of the absorption liquid 63, a flow rate adjusting mechanism, and the like via a liquid supply line 631 and an opening / closing valve V6. The liquid supply line 631 is connected to the above-described DIW supply unit 501 via the open / close valve V5, and supplies DIW as a cleaning liquid 64 for cleaning the absorbing liquid 63 adhering to the groove 62 of the ammonia absorbing unit 61. be able to.

  Further, the ammonia absorption part 61 is connected to the acidic drainage line 74 and the general drainage line 75 via the drainage line 632 and the flow path switching valve 702, and the liquid (absorption liquid 63) stored in the ammonia absorption part 61. The cleaning liquid 64) can be switched to these drain lines 74 and 75 and discharged. As shown in FIG. 1, the longitudinal cross-sectional shape of the groove portion 62 is formed with a tapered surface that gradually decreases from the inner peripheral edge and the outer peripheral edge of the ammonia absorbing portion 61 toward the center, and the liquid in the groove portion 62. It is easy to discharge.

  Further, the substrate processing apparatus is connected to a control unit 8 that controls the overall operation of the substrate processing apparatus. For example, the control unit 8 includes a computer having a CPU and a storage unit. The storage unit functions as a substrate processing apparatus, that is, delivers the wafer W to the wafer holding unit 10 and supplies various processing liquids to the rotating wafer W. Then, a program in which a group of steps (commands) for the operation for performing the process is assembled is recorded. Further, the control unit 8 outputs a control signal for executing the step group. This program is stored in a storage medium such as a hard disk, a compact disk, a magnetic optical disk, or a memory card, and installed in the computer therefrom.

  Next, the content of the operation executed in the substrate processing apparatus will be described with reference to FIGS. FIG. 3 shows a correspondence relationship between the sequence of processing performed on the wafer W by the substrate processing apparatus (upper side) and the state of the ammonia absorber 61 (lower side) during each processing period. In FIG. 3, the processing of the wafer W proceeds from the left end side in the direction indicated by the arrow, and the processing is executed in the order of SC1 processing → rinse cleaning → DHF processing → rinsing cleaning → IPA supply → shaking off drying. In FIGS. 4 and 6 to 8, a symbol “O” attached to each on-off valve V <b> 1 to V <b> 6 indicates a state in which the on-off valves V <b> 1 to V <b> 6 are opened and liquid is supplied from each supply unit 501 to 505. Reference numeral “S” indicates a state in which the supply of the liquid is stopped by closing them.

  First, as shown in FIG. 4, for example, before the wafer W is loaded, the absorbing solution 63 is supplied from the sulfuric acid supply unit 505 to the ammonia absorbing unit 61, and the absorbing solution 63 is stored in the groove 62 in advance. The supply of the absorption liquid 63 is stopped. Further, the supply of clean air from the FFU 45 and the exhaust from the cup exhaust port 35 are always performed, and a down flow is formed in the housing 41.

Next, the wafer W is loaded into the substrate processing apparatus via a loading / unloading port (not shown) provided on the side wall of the casing 41 by the external transfer arm, and the wafer W is received by the holding pins 12 via the lift pins 13. hand over.
At this time, the cup unit 30 raises the second cup 32 in response to the SC1 process to be executed next, while lowering the third cup 33, the air flowing into the cup unit 30 and the liquid shaken off from the wafer W. Is set to pass through the second flow path 321. The flow path switching valve 701 selects the alkaline exhaust line 72 as a connection destination of the cup exhaust path 36.

  Thereafter, the nozzles 51 to 53 are moved from the retracted position to the processing position, the wafer holding unit 10 is operated to rotate the wafer W around the vertical axis, and then the on-off valve V2 downstream of the SC1 supply unit 502 is opened. SC1 is supplied to the wafer W. SC1 spreads on the surface of the rotating wafer W, removes organic dirt and particles, reaches the end, and is shaken off from the wafer W.

  The SC 1 shaken off from the wafer W is guided by the guide ring 21 and flows into the second flow path 321, and is discharged from the drain port 323 to the alkaline drain system. On the other hand, the downflow formed in the housing 41 enters the second flow path 321 through the opening of the cup portion 30, passes through the liquid receiver 322 and the cup exhaust port 35, and enters the alkaline exhaust line 72. It is discharged towards.

  Most of the vapor and mist of SC1 supplied to the wafer W rides on the airflow flowing into the liquid receiver 322 and is separated into gas and liquid at the liquid receiver 322 and discharged as liquid to the liquid discharge port 323, or alkaline together with the airflow. It is discharged to the exhaust line 72. On the other hand, among the steam and mist of SC1 that did not get on the airflow flowing into the second flow path 321, the ammonia component lighter than air rises inside the housing 41 and flows down in the vicinity of the inner wall of the housing 41, etc. Stays in a weak area.

  The ammonia absorption part 61 of the present substrate processing apparatus is provided in such a region where ammonia is likely to stay, and as shown in FIG. 5, the liquid surface of the absorption liquid 63 is exposed toward the ammonia retention part. Therefore, the sulfuric acid in the ammonia absorption part 61 and ammonia contact. As a result, ammonia is absorbed by the absorbent 63 and reacts with sulfuric acid to produce an ammonium sulfate salt, and the ammonia is taken into the absorbent 63.

  Here, the absorption efficiency of the ammonia absorption into the absorption liquid 63 increases as the rate of the ammonia component contacting the liquid surface of the absorption liquid 63 increases. Therefore, at the time of SC1 supply, the air supply amount from the FFU 45 and the exhaust amount from the cup exhaust port 35 may be increased to increase the flow velocity of the airflow in the housing 41 and increase the ammonia absorption efficiency. By increasing the exhaust amount from the cup exhaust port 35, the amount of airflow flowing into the second flow path 321 is increased, and the amount of ammonia rising in the housing 41 is also reduced. In this respect, the flow rate adjustment valve provided in the supply fan 451 of the FFU 45 or the cup exhaust passage 36 corresponds to the flow rate adjustment unit of the present embodiment.

  When the processing of the wafer W by SC1 is executed for a predetermined time, the processing liquid supplied from the first nozzle 51 to the wafer W is switched to DIW as shown in FIG. The third cup 33 is raised in accordance with the switching of the processing liquid, the position of the airflow or the liquid is passed through the third flow path 331, and the connection destination of the cup exhaust path 36 is changed to discharge the liquid and gas. The tip is switched to the organic drainage system and the organic exhaust line 73.

  On the other hand, as shown in FIG. 3, the ammonia absorption part 61 is in a state where the absorption liquid 63 is continuously stored, and continues to absorb the ammonia released during the SC1 treatment. Then, when a preset time elapses during the rinse cleaning execution period, the flow path switching valve 702 is actuated as shown in FIG. 6 to connect the drain line 632 to the acidic drain line 74, and the ammonia absorption unit The absorbing liquid 63 in 61 is discharged. In order to increase the efficiency of absorption of ammonia into the absorption liquid 63, when the supply / exhaust amount to the housing 41 is increased, the supply / exhaust amount may be decreased at this timing, for example.

  When the absorbing solution 63 is discharged, the opening / closing valve V5 of the DIW supply unit 501 is opened, and the cleaning solution 64 (DIW) is supplied to the ammonia absorbing unit 61 to clean the groove 62. Thereafter, the flow path switching valve 702 is operated to close the acidic drainage line 74 and the drainage line 632, and the cleaning liquid 64 is stored in the ammonia absorption unit 61. By washing away the absorbing solution 63 of the ammonia absorbing portion 61, it is possible to prevent components such as sulfuric acid from volatilizing and diffusing in the housing and adhering to the wafer W when the wafer W is dried.

  When the rinse cleaning is performed for a preset time, the second cup 32 and the third cup 33 are lowered as shown in FIG. 7 to set the position where the airflow or liquid passes through the first flow path 311 and the cup exhaust. The connection destination of the path 36 is changed, and the liquid and gas discharge destinations are switched to the acidic drainage system and the acidic exhaust line 71. Thereafter, the processing liquid supplied to the wafer W is switched to DHF from the second nozzle 52, and the natural oxide is removed.

  When the DHF processing is executed for a predetermined time, the processing liquid supplied from the second nozzle 52 to the wafer W is switched to DIW, and DHF rinse cleaning is performed.

  After rinsing for a preset time, the flow path switching valve 702 is operated to connect the drain line 632 to the general drain line 75 as shown in FIG. 8, and the cleaning liquid 64 in the ammonia absorption part 61 is discharged. To do. As a result, the surface of the groove portion 62 of the ammonia absorbing portion 61 is exposed, but the absorbing liquid 63 adhering to the surface of the groove portion 62 is washed with the cleaning liquid 64 and discharged to the outside.

  Thereafter, the supply of DIW is stopped, while the on-off valve V4 downstream of the IPA supply unit 504 is opened to supply IPA, which is a drying liquid, to the third nozzle 53. The second cup 32 and the third cup 33 are raised in accordance with the switching of the processing liquid to set the position where the airflow and the liquid pass through the third flow path 331, and the connection destination of the cup exhaust path 36 is changed. The liquid and gas discharge destinations are switched to the organic drainage system and the organic exhaust line 73. After a predetermined time has elapsed, the supply of IPA is stopped. As a result, the DIW remaining on the rotating wafer W is shaken off together with the IPA, and the wafer W is in a dry state.

By discharging the cleaning liquid 64 from the ammonia absorbing unit 61 before drying the wafer W, it is possible to suppress an increase in humidity in the housing 41 and to suppress generation of a watermark due to condensation on the surface of the wafer W. it can. Note that the cleaning liquid 64 may be discharged without being stored in the ammonia absorption unit 61 at the above-described timing when the SC1 is cleaned, and the DHF treatment or the rinse cleaning may be performed while the ammonia absorption unit 61 is empty.
After the wafer W is dried, the nozzles 51 to 53 are retracted to the retracted position, an external transfer arm is moved into the housing 41, and the processed wafer W is unloaded.

  The substrate processing apparatus according to the present embodiment has the following effects. Since the ammonia absorption part 61 which stored the acidic absorption liquid 63 which absorbs ammonia is provided in the housing | casing 41 in which the process of the wafer W using SC1 containing ammonia is performed, when using SC1, the housing | casing 41 is provided. The ammonia diffused in the inside can be absorbed, and the adhesion of ammonia to the wafer W can be suppressed.

Further, if ammonia is present during chemical cleaning with DHF, the ammonia is combined with DHF, and ammonium fluoride (NH ₄ F) is generated. The produced ammonium fluoride enters the liquid film of pure water formed on the surface of the wafer W during the rinsing process. In the subsequent drying process, the pure water on the surface of the wafer W is replaced with IPA, and then the wafer W is dried. However, the ammonium fluoride remaining in the pure water remains on the surface of the wafer W after drying. It was the cause of polluting. Since the absorbing liquid 63 of the ammonia absorbing unit 61 absorbs the ammonia diffused into the housing 41 when the SC1 is used, the adhesion of ammonia to the wafer can be suppressed during the processing of the wafer W after the SC1.

  Here, the configuration and arrangement position of the ammonia absorbing portion 61 are not limited to the examples shown in FIGS. For example, in FIG. 9, the ammonia absorbing portion 61 a is formed by forming a groove portion 62 that can store the absorbing solution 63 and the cleaning solution 64 on the upper surface of the first cup 31 disposed at the outermost position of the cup portion 30. A configured example is shown. By disposing the ammonia absorbing portion 61a in the vicinity of the wafer W, ammonia can be absorbed near the generation source when SC1 is supplied, and adhesion of ammonia to the wafer W can be suppressed. In FIG. 9, the same components as those of the substrate processing apparatus shown in FIG.

  In addition, the ammonia absorber 61 is not limited to the case where the liquid surface of the absorbent 63 is arranged in an annular shape so as to surround the wafer W when viewed from the upper surface side. For example, when ammonia is likely to stay at the four corners on the ceiling side of the rectangular parallelepiped casing 41, the cup-shaped ammonia absorbing portions 61 may be disposed at the four corner positions.

  Further, the configuration of the ammonia absorption part 61 is not limited to a system in which the container-shaped ammonia absorption part 61 in which the groove part 62 and the like are formed is filled with the absorbent 63 and stored. For example, the absorbent may be stored by disposing a member having a high water retention capacity such as a sponge on the tray and impregnating the absorbent with the absorbent 63.

  Furthermore, the combination of the processing liquids supplied to the wafer W is not limited to the above example. Instead of DHF or in addition to DHF, another type of chemical solution may be supplied, or the processing by SC1 may be performed alone. Even when the combination of the processing liquids is changed, the ammonia absorption unit 61 is in a state of storing the absorption liquid 63 when the SC1 is supplied to the wafer W, and the cleaning liquid 64 is cleaned and cleaned with the cleaning liquid 64 before the wafer W is dried. Should be discharged.

  Further, in the ammonia absorption unit 61, as described with reference to FIG. 3 and the like, it is not an essential requirement to perform the discharge of the absorption solution 63, the cleaning with the cleaning solution 64, and the discharge operation of the ammonia absorption unit 61. The wafer W may be processed with each processing solution while the absorbing solution 63 is stored in the ammonia absorbing unit 61, and a plurality of wafers W may be processed. In this case, it is preferable to replace the absorbing solution 63 with a new absorbing solution 63 at a timing when the absorbing ability of ammonia by the absorbing solution 63 falls below a predetermined reference value.

  The configuration of the substrate processing apparatus is not limited to the examples shown in FIGS. For example, the liquid is discharged toward the common drainage port without providing the second cup 32 and the third cup 33 that can be moved up and down in the cup portion 30, and the discharge destination is switched by a flow path switching valve or the like provided downstream thereof. You may do.

W Wafer 10 Wafer holding part 30 Cup part 35 Cup exhaust port 41 Housing 45 FFU (fan filter unit)
501 DIW supply unit 502 SC1 supply unit 503 DHF supply unit 504 IPA supply unit 505 Sulfuric acid supply unit 51 First nozzle 52 Second nozzle 53 Third nozzle 61 Ammonia absorption unit 63 Absorption liquid 64 Cleaning liquid 8 Control unit

Claims (15)

A substrate holding unit disposed in the housing and holding the substrate horizontally;
A chemical nozzle for supplying a chemical solution containing ammonia to the surface of the substrate;
An ammonia absorption part that is provided in the casing and stores an acidic absorbent that absorbs ammonia diffused in the casing;
An absorption liquid supply section for supplying an acidic absorption liquid to the ammonia absorption section ,
The substrate processing apparatus , wherein the ammonia absorption part is provided at a position higher than the substrate held by the substrate holding part . A discharge part for discharging the liquid stored in the ammonia absorption part;
When supplying a chemical solution containing ammonia from the chemical solution nozzle to the surface of the substrate, supplying an acidic absorption solution to the ammonia absorption unit, and before starting drying of the substrate, the discharge unit to the ammonia absorption unit absorbing liquid substrate processing apparatus according to claim 1, and a control unit for outputting a control signal to perform the method comprising: discharging, comprising the a. A rinsing liquid nozzle that supplies a rinsing liquid for rinsing and cleaning the chemical liquid to the substrate, and a drying liquid nozzle that supplies a drying liquid containing an organic solvent,
The controller, after stopping the supply of the rinse liquid, supplying the drying liquid from the drying liquid nozzle to the substrate, drying the substrate, and before starting the supply of the drying liquid, The substrate processing apparatus according to claim 2 , wherein a control signal is output so as to execute the discharging of the absorbing solution of the ammonia absorbing unit from the discharging unit. When the chemical nozzle is a first chemical nozzle, the surface of the substrate includes a second chemical nozzle that supplies another chemical different from the chemical containing ammonia,
The controller is configured to supply the other chemical solution nozzle from the second chemical solution nozzle during a period from when the chemical solution containing ammonia to the substrate and the subsequent supply of the rinse solution are supplied to when the substrate starts drying. of the supply of the chemical, in place of the other drug solution, according to claim 3, characterized in that outputs a control signal to perform to make a supply of the rinse liquid from the rinse liquid nozzle Substrate processing equipment. The ammonia absorber is disposed so that a contact region between the acidic absorbent and the atmosphere in the housing surrounds the substrate held by the substrate holder in the circumferential direction when viewed from the upper surface side. the substrate processing apparatus according to any one of claims 1 to 4, wherein. A cup that is disposed around the substrate holding portion and receives the liquid shaken off from the rotating substrate;
An air supply unit for supplying clean gas into the housing from the ceiling side of the housing;
A bottom portion of the housing, through the cup, the substrate according to any one of the exhaust unit for exhausting the enclosure, claims 1, characterized in that with a 5 Processing equipment. When the chemical nozzle is a first chemical nozzle, a second chemical nozzle that supplies another chemical different from the chemical containing ammonia to the surface of the substrate;
A flow rate adjusting unit for adjusting the flow rate of the airflow flowing in the housing,
During the period in which the chemical liquid containing ammonia is supplied from the first chemical liquid nozzle, the control signal is set so that the flow rate of the airflow flowing in the housing is increased as compared with the period in which the other chemical liquid is supplied from the second chemical liquid nozzle. The substrate processing apparatus according to claim 6 , further comprising the control unit that outputs a signal. Absorbing solution of the acid is sulfuric acid, hydrochloric acid, a substrate processing apparatus according to any one of claims 1 to 7, characterized in that it comprises a solution of at least one acid selected from the group consisting of hydrofluoric acid. Supplying a chemical solution containing ammonia to the surface of the substrate held horizontally in the housing;
A step of absorbing the ammonia diffused in the casing in an acidic absorbing solution stored in an ammonia absorbing section disposed in a position higher than the holding position of the substrate in the casing. A substrate processing method. When supplying a chemical liquid containing ammonia from the chemical liquid nozzle to the surface of the substrate, supplying an acidic absorbing liquid to the ammonia absorbing section;
The substrate processing method according to claim 9 , further comprising a step of discharging the acidic absorbing liquid of the ammonia absorbing portion before starting to dry the substrate. Supplying a rinse solution for rinsing and cleaning the chemical solution to the substrate;
After the supply of the rinse liquid is stopped, the substrate is dried after the drying liquid is supplied from the drying liquid nozzle to the substrate;
The substrate processing method according to claim 10 , further comprising: discharging the absorption liquid of the ammonia absorption unit from the discharge unit before starting the supply of the drying liquid. After the supply of the chemical solution containing ammonia to the substrate and the subsequent supply of the rinse solution, the supply of another chemical solution different from the chemical solution containing ammonia during the period until the substrate starts drying The substrate processing method according to claim 11 , further comprising a step of supplying a rinsing liquid instead of the other chemical liquid. The substrate processing according to claim 12 , further comprising a step of increasing a flow rate of an airflow flowing in the housing during a period in which the chemical liquid containing ammonia is supplied, compared to a period in which another chemical liquid is supplied. Method. Absorbing liquid sulfuric the acid, hydrochloric acid, a substrate processing method according to any one of claims 9 to 13, characterized in that it comprises a solution of at least one acid selected from the group consisting of hydrofluoric acid. A storage medium storing a computer program used in a substrate processing apparatus for processing a substrate by supplying a chemical solution containing ammonia to the surface of the substrate held horizontally,
Storage medium wherein a program, characterized in that the steps to perform the substrate processing method according to any one of claims 9 to 14 is assembled.

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