JP2006222468A - Substrate processing device, substrate processing method and cleaning method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate processing device by which throughput of substrate processing is enhanced by performing oxidation treatment with plasma-activated radical, in the substrate processing device in which adsorption and oxidization for a molecular layer are alternately repeated, and to provide a substrate processing method using the substrate processing device. <P>SOLUTION: The substrate processing device includes a processing vessel provided with a substrate holding stage holding a substrate to be processed thereon, a process gas inlet formed on a first side of the substrate holding stage in the processing vessel, a radical source formed on a second side different from the first side of the substrate holding stage of the processing vessel, a first exhaust port formed on the first side in the processing vessel, a second exhaust port formed on the second side in the processing vessel, and an exhaust system which is combined with the first exhaust port via a first variable conductance valve and with the second exhaust port via a second variable conductance valve. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a semiconductor device, and more particularly to a substrate processing apparatus and a substrate processing method used for manufacturing an ultrafine high-speed semiconductor device having a high dielectric film.

  In today's ultra-high-speed semiconductor devices, gate lengths of 0.1 μm or less are becoming possible as the miniaturization process advances. In general, the operation speed of a semiconductor device increases with miniaturization. However, in such a semiconductor device that is extremely miniaturized, the thickness of the gate insulating film is reduced according to the scaling law as the gate length is shortened by miniaturization. It is necessary to let

However, when the gate length is 0.1 μm or less, the thickness of the gate insulating film needs to be set to ₁ to ₂ nm or less when SiO ₂ is used, but in such a very thin gate insulating film, The problem that the tunnel current increases and, as a result, the gate leakage current increases cannot be avoided.

Conventionally In these circumstances, the dielectric constant is much larger than that of the SiO ₂ film, Ta ₂ O ₅ film thickness is smaller when the actual film thickness for this purpose in terms of SiO ₂ film be larger, It has been proposed to apply a high dielectric material such as Al ₂ O ₃ , ZrO ₂ , HfO ₂ , ZrSiO ₄ , HfSiO ₄ to the gate insulating film. By using such a high dielectric material, a gate insulating film having a thickness of 1 to 2 nm or less can be used even in a very fine ultrahigh-speed semiconductor device with a gate length of 0.1 μm or less, Gate leakage current due to the tunnel effect can be suppressed.

When such a high dielectric gate insulating film is formed on the Si substrate, the thickness is 1 nm or less in order to suppress diffusion of the metal elements constituting the high dielectric gate insulating film into the Si substrate. Typically, it is necessary to form a SiO ₂ film of 0.8 nm or less as a base oxide film on the Si substrate, and to form the high dielectric gate insulating film on the very thin SiO ₂ base oxide film. . At this time, the high dielectric gate insulating film must be formed so that no defects such as interface states are formed in the film. Further, when the high dielectric gate insulating film is formed on the base oxide film, the composition is mainly composed of SiO ₂ from the side in contact with the base oxide film toward the main surface on the high dielectric gate insulating film. It is preferable to gradually change the composition to a composition mainly composed of a high dielectric material.

  If an attempt is made to form a high dielectric gate insulating film so as not to include defects, a plasma process involving charged particles cannot be used. For example, when such a high dielectric gate insulating film is formed by a plasma CVD method, defects that act as traps for hot carriers are formed in the film as a result of plasma damage.

  On the other hand, if such a high dielectric gate insulating film is to be formed by a thermal CVD method, it is necessary to set the substrate temperature high, so that it is easy to crystallize and the surface roughness increases. Further, the inventors of the present invention have found that it is difficult to obtain a uniform film thickness distribution due to the uniformity of the substrate temperature because the film formation rate is likely to change depending on the temperature of the substrate. In other words, when such a high dielectric gate insulating film is formed by a conventional CVD method, the roughness of the film surface tends to increase, and it is difficult to ensure the uniformity of the film thickness. Therefore, when it is applied to the gate insulating film of a MOS transistor that requires highly accurate film thickness control, the operating characteristics of the semiconductor device are seriously affected.

  Therefore, the inventor of the present invention has previously proposed a substrate processing method and a processing apparatus described below in Patent Document 3 in order to solve the above problems.

  FIG. 1 shows the configuration of a substrate processing apparatus (ALD film forming apparatus) 10 that performs the ALD film forming process previously proposed by the inventors of the present invention. In the ALD film forming process, the first source gas and the second source gas are alternately supplied onto the substrate to be processed in the form of a laminar flow that flows along the surface of the substrate to be processed. The source gas molecules are adsorbed on the surface of the substrate to be processed and reacted with the source gas molecules in the second source gas to form a film having a thickness of one molecular layer. By repeating this process, a high-quality dielectric film that can be used as a gate insulating film, particularly a high dielectric film, is formed on the surface of the substrate to be processed.

  Referring to FIG. 1, the substrate processing apparatus 10 includes processing gas inlets 13A and 13B facing each other with a substrate 12 to be processed, and processing gas inlets 13A and 13B, respectively, with the substrate 12 to be processed. It includes a processing vessel 11 having opposing elongated slit-like exhaust ports 14A and 14B, and the exhaust ports 14A and 14B are connected to a trap 100 via conductance valves 15A and 15B, respectively. 100 is exhausted.

  Further, another processing gas introduction port 13C is formed in the processing container 11 adjacent to the processing gas introduction port 13A so as to face the exhaust port 14A.

The processing gas inlet 13A is connected to a first outlet of a switching valve 16A. The switching valve 16A is ZrCl via a first raw material supply line 16a including a valve 17A, a mass flow controller 18A, and another valve 19A. ₂ is connected to a raw material container 20A. Further, a purge line 21a that includes valves 21A and 22A and supplies an inert gas such as Ar is provided adjacent to the first raw material supply line 16a.

  Further, the switching valve 16A is connected to an inert gas source such as Ar, and is connected to a valve purge line 23a including mass flow controllers 23A and 24A. The second outlet of the switching valve 16A is connected to the purge line 100a. To the trap 100.

Similarly, the processing gas inlet 13B is connected to a first outlet of a switching valve 16B, and the switching valve 16B has a first raw material supply line 16b including a valve 17B, a mass flow controller 18B, and another valve 19B. To the raw material container 20B holding H ₂ O. Further, a purge line 21b including valves 21B and 22B and supplying an inert gas such as Ar is provided adjacent to the first raw material supply line 16b.

  Further, the switching valve 16B is connected to an inert gas source such as Ar, and is connected to a valve purge line 23b including mass flow controllers 23B and 24B. The second outlet of the switching valve 16B is connected to the purge line 100b. To the trap 100.

Further, the processing gas inlet 13C is connected to a first outlet of a switching valve 16C, and the switching valve 16C is connected via a first raw material supply line 16c including a valve 17C, a mass flow controller 18C, and another valve 19C. It is connected to a raw material container 20C holding SiCl ₄ . Further, a purge line 21c including valves 21C and 22C and supplying an inert gas such as Ar is provided adjacent to the first raw material supply line 16c.

  Further, the switching valve 16C is connected to an inert gas source such as Ar, and a valve purge line 23c including mass flow controllers 23C and 24C is connected. The second outlet of the switching valve 16C is connected to the purge line 100c. To the trap 100.

  Further, the substrate processing apparatus 10 of FIG. 1 is provided with a control device 10A for controlling the film forming process, and the control device 10A, as will be described later with reference to FIGS. 4 to 7, the switching valves 16A to 16C and the conductance valve. Control 15A and 15B.

  FIG. 2 shows details of a portion including the processing container 11 of FIG. However, in FIG. 2, portions corresponding to FIG. 1 are denoted by the same reference numerals.

  Referring to FIG. 2, the processing vessel 11 has an outer vessel 201 made of Al or the like and an inner reaction vessel 202 made of quartz glass, and the inner reaction vessel 202 is defined in the outer vessel 201, The outer container 201 is housed in a recess that is covered by a cover plate 201 </ b> A that forms part of the outer container 201.

  The inner reaction vessel 202 includes a quartz bottom plate 202A that covers the bottom surface of the outer vessel 201 in the recess, and a quartz cover 202B that covers the quartz bottom plate 202A in the recess, and further, on the bottom of the outer vessel, A circular opening 201 </ b> D is formed in which a disk-shaped substrate holding table 203 holding the target substrate W is accommodated. A heating mechanism (not shown) is provided in the substrate holder 203.

  The substrate holder 203 is held by a substrate transfer unit 204 provided at the lower part of the outer processing container 201 so as to be rotatable and simultaneously movable up and down. The substrate holding table 203 is held so as to be movable up and down between the uppermost process position and the lowermost substrate loading / unloading position. The process position is determined by the surface of the substrate W to be processed on the holding table 203 being It is determined so as to substantially coincide with the surface of the quartz bottom plate 202A.

  On the other hand, the substrate loading / unloading position is set corresponding to the substrate loading / unloading opening 204A formed on the side wall surface of the substrate transfer unit 204, and when the substrate holding table 203 is lowered to the substrate loading / unloading position, A transfer arm 204B is inserted from the substrate loading / unloading port 204A, and the substrate to be processed W lifted from the surface of the substrate holding table 203 is held and lifted by a lifter pin (not shown) and sent to the next step. In addition, the transfer arm 204B introduces a new substrate W to be processed into the substrate transfer unit 204 through the substrate loading / unloading opening 204A and places it on the substrate holding table 203.

  The substrate holding table 203 holding the new substrate W to be processed is rotatably held by the rotating shaft 205B held by the magnetic seal 205A in the bearing portion 205 and is also movable up and down. A space in which the moving shaft 205 </ b> B moves up and down is sealed by a partition such as a bellows 206. At this time, the space is evacuated to a higher vacuum state than the inside of the inner container 202 through an exhaust port (not shown), and contamination to the substrate processing process performed in the inner container 202 is avoided.

  In order to reliably perform such differential evacuation, the substrate holder 203 is provided with a guard ring 203A made of quartz glass so as to surround the substrate W to be processed. The guard ring 203A suppresses a conductance between the substrate holding table 203 and a side wall surface of the opening 201D formed so as to accommodate the substrate holding table in the outer container 201, thereby the bellows. When the space defined by 206 is evacuated to a high vacuum, a differential pressure is reliably formed between the inner reaction vessel 202 and the inner reaction vessel 202.

  The opening 201D formed at the bottom of the outer container 201 has a side wall surface covered with a quartz liner 201d, and the quartz liner 201d extends further downward to cover the inner wall of the substrate transfer unit 204.

  Exhaust grooves 201a and 201b connected to an exhaust device are formed on both sides of the opening 201D at the bottom of the outer container 201, and the exhaust groove 201a is connected via a conduit 207a and a conductance valve 15A. The exhaust groove 201b is exhausted through a conduit 207b and a conductance valve 15B. In the state of FIG. 2, the conductance valve 15A is set in an open state, and the conductance valve 15B is set in a substantially closed state. The conductance valves 15A and 15B do not close completely even in the closed state in order to realize a highly reliable open / close state, but leave a valve opening of about 3%.

  The exhaust groove portions 201a and 201b are covered with a liner 208 made of quartz glass, and slit-shaped openings 209A and 209B are formed in the quartz bottom plate 202A corresponding to the exhaust groove portions 201a and 201b. In the embodiment of FIG. 2, the rectifying plate 209 in which the exhaust ports 14A or 14B described in FIG. 1 are formed in the slit-shaped openings 209A and 209B is used for the purpose of promoting the exhaust inside the inner reaction vessel 202. Is formed.

  Further, in the inner reaction vessel 202, quartz gas nozzles 13A and 13B are provided so as to face the exhaust grooves 201a and 201b, respectively, with the wafer 12 therebetween. Therefore, the first processing gas introduced from the gas nozzle 13A flows along the surface of the substrate 12 to be processed in the inner reaction vessel 202 and is exhausted from the opposing exhaust port 14A through the conductance valve 15A. . Similarly, the second processing gas introduced from the gas nozzle 15B flows along the surface of the substrate W to be processed in the inner reaction vessel 202, and is exhausted from the opposing exhaust port 14B through the conductance valve 15B. The In this way, the first and second processing gases are alternately flown from the gas nozzle 13A to the exhaust port 14A or from the gas nozzle 13B to the exhaust port 14B, whereby the above-described molecular layer as a basic unit is formed. Formation becomes possible.

  FIG. 3 shows the configuration of the quartz bottom plate 202A constituting the inner reaction vessel 202 in detail.

  Referring to FIG. 3, a circular opening 202a corresponding to the substrate W to be processed is formed in the quartz bottom plate 202A, and both sides of the opening 202a correspond to the exhaust grooves 201a and 201b. Openings 209A and 209B are formed. Further, in the example of FIG. 3, a rectifying plate 209 having a slit constituting the exhaust port 14A or 14B corresponding to the openings 209A and 209B is provided. The quartz bottom plate 202A has an opening 210a corresponding to the gas nozzle 13A and an opening 210b corresponding to the gas nozzle 13B. By forming a plurality of openings 210a or 210b in the quartz bottom plate 202A, a plurality of gas nozzles 13A or 13B can be provided in the inner processing vessel 202.

FIG. 4 shows an ALD process sequence executed under the control of the control apparatus 10A when the ZrO ₂ film is formed on the substrate 12 to be processed one molecular layer at a time in the substrate processing apparatus 10 of FIGS. It is a flowchart.

  Referring to FIG. 4, in the first step 1, the conductance valves 15A and 15B are opened, and the switching valves 16A and 16B both pass the processing gas in the processing gas supply lines 16a and 16b to the purge line 100a and 16b, respectively. The first state, that is, the purge state, is controlled so as to be supplied to the trap 100 via 100b. As a result, Ar gas in the purge line 23a and Ar gas in the purge line 23b are supplied into the quartz reaction vessel 202 through the processing gas inlets 13A and 13B, respectively. The Ar purge gas thus supplied is discharged to the trap 100 from the exhaust ports 14A and 14B, respectively.

  Next, in step 2, the opening of the conductance valve 15A is increased and the opening of the conductance valve 15B is decreased. As a result, a gas flow that flows from the gas inlet 13A to the exhaust port 14A is generated in the quartz reaction vessel 202.

Next, in step 3, the switching valve 16A is switched from the first state to the second state, and the ZrCl ₄ gas in the processing gas supply line 16a is sent from the first processing gas inlet 13A to the quartz reaction vessel. 202 is introduced as a gas flow LF ₁ as shown in FIG. As described above, the ZrCl ₄ gas flow LF ₁ introduced in this way flows as a laminar flow over the surface of the substrate 12 to be processed and is discharged from the exhaust port 14A. Through this process, about one molecular layer of ZrCl ₄ is adsorbed on the surface of the substrate 12 to be processed. In the step 3, the second switching valve 16B is in the first state, and the Ar purge gas in the line 23a is introduced into the quartz reaction vessel 202 from the second processing gas inlet 13B. As a result, there is no problem that the ZrCl ₄ process gas introduced from the first process gas inlet 13A enters the second process gas inlet 13B and causes precipitates.

  Next, in step 4, the switching valve 16A is returned to the original first state, and the reaction vessel 202 is purged with Ar gas.

  Further, in step 5, the opening of the conductance valve 15A is decreased and the opening of the conductance valve 15B is increased. As a result, a gas flow that flows from the gas inlet 13B to the exhaust port 14B is generated in the quartz reaction vessel 202.

Next, in step 6, the switching valve 16B is switched from the first state to the second state, and the H ₂ O gas in the processing gas supply line 16b is transferred from the second processing gas inlet 13B to the quartz reaction. in a container 202, it is introduced as a gas stream LF ₂ as shown in FIG. As described above, the H ₂ O gas flow LF ₂ introduced in this way flows as a laminar flow on the surface of the substrate to be processed 12 and is discharged from the exhaust port 14B. Through this process, ZrCl ₄ previously adsorbed on the surface of the substrate to be processed 12 is hydrolyzed, and a ZrO ₂ film having a thickness of about one molecular layer is formed. In the step 6, the first switching valve 16A is in the first state, and the Ar purge gas in the line 23a is introduced into the quartz reaction vessel 202 from the second processing gas inlet 13A. As a result, there is no problem that the H ₂ O gas introduced from the second processing gas inlet 13B enters the first processing gas inlet 13A and precipitates are generated.
JP-A-2-74587 Special table 2001-514440 gazette JP 2002-151489 A US Patent No. 516365

  By the way, in such an ALD process, since it is preferable to form a laminar flow of the source gas in the quartz reaction vessel 202, the gas nozzles 13A and 13B have elongated slit-like nozzle openings, and exhausts correspondingly. The mouths 14A and 14B are also formed in an elongated slit shape.

  Therefore, when purging the reaction vessel 202 in step 1 of FIG. 4, the purge gas is exhausted from the exhaust ports 14A and 14B, but the conductance of the slit-shaped exhaust ports 14A and 14B is limited, For this reason, when the substrate processing apparatus 10 is designed to handle a substrate having a large diameter as the substrate 12 to be processed, for example, a wafer having a diameter of 30 cm, a reaction container having a large volume even if the conductance valves 15A and 15B are fully opened. It takes time to evacuate 202, and the throughput of substrate processing decreases. On the other hand, if the opening area of the exhaust ports 14A and 14B, particularly the width measured along the gas flow direction, is increased in order to improve the efficiency during exhaust, the flow of the source gas in the reaction vessel 202 is disturbed. Therefore, there is a possibility that the adsorption of the raw material gas of one molecular layer cannot be performed reliably.

Further, the ALD method using such H ₂ O adsorbed on metallic species of the oxidation, such as ZrCl _4, H ₂ O is treated inner wall of the container and the switching valve 16A, easily adsorbed to 16B, Therefore, in FIG. 4 In step S6, after introducing H ₂ O into the processing vessel from the switching valve 16B, a long purge time was required in step S1. As a result, it is difficult to improve the throughput of the substrate processing in the film forming process by the so-called atomic layer ALD apparatus by the adsorption of the molecular layer as compared with the film forming process by the normal CVD apparatus.

  In U.S. Pat. No. 516365, a vapor source is introduced from one end of a processing vessel that holds a substrate to be processed horizontally, and a radical source is provided as one of the raw material supply sources in a CVD apparatus configured to exhaust from multiple ends. A configuration is disclosed.

  Therefore, in the substrate processing apparatus of FIG. 2, it is conceivable to oxidize the metal molecular layer adsorbed on the surface of the substrate to be processed by oxygen radicals supplied from the radical source. However, the apparatus of FIG. Therefore, it is difficult to provide such a radical source.

  In addition, the above-mentioned US Pat. No. 516365 connects such a radical source to a part of a raw material supply line via a valve, but such a configuration alternately supplies a gas phase raw material as in the present invention. When applying to a substrate processing apparatus of this type, it is necessary to switch the processing gas and radicals within the processing container preferably in an extremely short time of 0.1 seconds or less, and repeatedly. The technology that makes this possible has not been known.

  By the way, in general, in a film forming apparatus, it is necessary to periodically remove deposits deposited during film formation in a processing container or a reaction container. Fluorine gas is used. In particular, the cleaning efficiency can be greatly improved by activating such a cleaning gas by plasma treatment and using the formed radicals.

  However, in the substrate processing apparatus 10 for the ALD process shown in FIGS. 1 and 2, the quartz reaction vessel 202 needs to have a laminar flow in the reaction vessel 202, so that it is at most about 5 to 20 mm. As described above, it was difficult to provide a radical source. For this reason, it is difficult for the substrate processing apparatus 10 to perform efficient cleaning using radicals.

  SUMMARY OF THE INVENTION Accordingly, it is a general object of the present invention to provide a new and useful substrate processing apparatus and a valve device used in such a substrate processing apparatus, which solve the above problems.

  A more specific subject of the present invention is a substrate processing apparatus in which adsorption and oxidation of molecular layers are alternately repeated, and the substrate can improve the throughput of the substrate processing by performing the oxidation processing with radicals excited by plasma. A processing apparatus and a substrate processing method using the substrate processing apparatus are provided.

  Another object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of performing efficient cleaning using radicals in a substrate processing apparatus that performs an ALD process.

The present invention solves the above problems.
As described in claim 1,
A processing container having a substrate holding table for holding a substrate to be processed;
A processing gas inlet formed on the first side of the substrate holder in the processing container;
A radical source formed on a second side of the processing container different from the first side with respect to the substrate holder;
A first exhaust port formed on the first side in the processing vessel;
A second exhaust port formed on the second side in the processing container;
A substrate processing apparatus comprising: an exhaust system coupled to the first exhaust port via a first variable conductance valve; and an exhaust system coupled to the second exhaust port via a second variable conductance valve; As described in item 2,
4. The substrate processing apparatus according to claim 1, wherein the radical source is turned off while a processing gas is being introduced from the processing gas inlet, or as described in claim 3.
The substrate processing apparatus according to claim 1, wherein the supply of the oxidation processing gas to the radical source is interrupted while the processing gas is being introduced from the processing gas introduction port. As described in item 4,
While the processing gas is being introduced from the processing gas inlet, the first variable conductance valve is closed, the second variable conductance valve is set to a predetermined opening, and the radical source is subjected to the oxidation treatment. 4. While gas is supplied, the first variable valve conductance valve is set to a predetermined opening and the second variable conductance valve is closed. With the substrate processing apparatus according to claim 1 or as described in claim 5,
The substrate source according to claim 1, wherein the radical source is a remote radical source, or as described in claim 6.
The substrate processing apparatus according to any one of claims 1 to 5, further comprising a rotation mechanism that rotates the substrate to be processed, or as described in claim 7.
The substrate processing apparatus according to claim 1, wherein the radical source is further coupled to the exhaust system via a third variable conductance valve. As described in 8,
The radical source is coupled to the substrate processing apparatus and the exhaust system by a branch pipe having a first branch and a second branch, and the first branch includes the second variable conductance valve. The substrate processing apparatus according to claim 7, wherein the radical supply source is coupled to the exhaust system, and the second branch is coupled to the exhaust system via the third variable conductance valve. As described in claim 9,
The substrate processing apparatus according to claim 7 or 8, wherein the first and second variable conductance valves are simultaneously opened when purging the inside of the processing vessel, or as described in claim 10. In addition,
The substrate processing apparatus according to claim 7, wherein the first, second, and third variable conductance valves are simultaneously opened when purging the inside of the processing container. Or as described in claim 11
13. The substrate processing apparatus according to claim 7, wherein the first and second variable conductance valves have substantially the same configuration, or according to claim 12. Like
The substrate processing apparatus according to any one of claims 7 to 10, wherein the radical source is a remote radical source that is supplied with oxygen gas and forms oxygen radicals. As stated,
The substrate processing apparatus according to any one of claims 7 to 11, wherein the radical source is a remote radical source that is supplied with nitrogen gas and forms nitrogen radicals. As stated,
The substrate processing apparatus according to any one of claims 7 to 11, further comprising a turning mechanism for turning the substrate to be processed, or as described in claim 15.
The process container has a flat shape, and the process gas inlet forms a flat sheet-like process gas flow in the process container. According to the substrate processing apparatus according to claim or as described in claim 16,
18. The substrate processing apparatus according to claim 15, wherein the processing container defines a process space having a height of 0.5 to 8 mm on the substrate to be processed, or as described in claim 17. ,
19. The substrate processing apparatus according to claim 15, wherein the processing container defines a process space having a height of 0.5 to 3.5 mm on the substrate to be processed. like,
The substrate gas processing apparatus according to any one of claims 7 to 17, wherein the processing gas flow forms a laminar flow in the processing container, or as described in claim 19.
A substrate holding table for holding a substrate to be processed, and a processing container exhausted at an exhaust port;
A first raw material supply nozzle that is formed on the first side of the substrate holder in the processing container and introduces a first processing gas into the processing container in the form of a first laminar flow;
A second raw material supply nozzle that is formed on the second side of the substrate holder in the processing container and introduces a second processing gas into the processing container in the form of a second laminar flow;
A slit-shaped first exhaust port formed on the second side in the processing vessel and exhausting the first laminar flow;
A slit-shaped second exhaust port formed on the first side in the processing vessel and exhausting the second laminar flow;
A first exhaust pipe coupled to the first exhaust port; a second exhaust pipe coupled to the second exhaust port and provided with a conductance variable valve;
21. A substrate processing apparatus comprising: a cleaning gas supply source coupled to the second exhaust pipe between the second exhaust port and the conductance variable valve; or like,
The substrate processing apparatus according to claim 19, wherein the cleaning gas supply source is a remote radical source that forms radicals of the cleaning gas, or as described in claim 21.
(A) purging the inside of the processing container;
(B) A processing gas is introduced into the processing container from a first side of the substrate to be processed, and processing gas molecules are adsorbed on the surface of the substrate to be processed, and then the first gas is applied to the substrate to be processed. Exhausting from a second side opposite the side;
(C) purging the inside of the processing container after the step (B);
(D) After the step (C), radicals are introduced into the processing container from the first side of the substrate to be processed to oxidize the processing gas molecules adsorbed on the surface of the substrate to be processed. In the substrate processing method comprising the step of exhausting from the second side,
The radical is formed by a radical source;
In the steps (A) and (C), the radical is caused to flow from the radical source to the exhaust system, and in the step (D), the radical is supplied into the processing container. Or as described in claim 22
The substrate processing method according to claim 21, wherein the radical source is continuously driven during the steps (A) to (D), or as described in claim 23,
In the steps (A) and (C), the purge step includes a step of evacuating the processing container using a part of a path for supplying the radical from the radical source to the processing container. According to the substrate processing method of claim 21 or 22, or as described in claim 24,
In the processing container, a processing gas is flowed from the first side to the second side opposite to the first side along the surface of the processing substrate held in the processing container, and the processing target substrate Adsorbing process gas molecules on the surface;
Purging the inside of the processing vessel;
In the processing container, flowing an oxidation processing gas from the first side to the second side along the surface of the substrate to be processed, and oxidizing the processing gas molecules adsorbed on the surface of the substrate to be processed; A substrate processing method comprising:
The substrate processing method comprising the step of activating the oxidizing gas in the processing vessel by an ultraviolet light excitation process on the first side of the substrate to be processed to form radicals, or As described in 25,
A substrate holding table for holding a substrate to be processed; a processing container evacuated at first and second exhaust ports formed on the first and second sides of the substrate holding table, respectively; A source gas supply system that alternately supplies the first and second source gases from the second side to the first side and from the first side to the second side, respectively. A method for cleaning a substrate processing apparatus comprising:
In a state where the processing container is exhausted at the first exhaust port, the cleaning gas is passed through the second exhaust port from the exhaust pipe coupled to the second exhaust port. According to a cleaning method characterized in that it comprises a step of introducing or as described in claim 26,
The problem is solved by the cleaning method according to claim 25, wherein the cleaning gas contains radicals.

  According to the present invention, by using a high-speed rotary valve having a rotatable valve body formed with a plurality of slit-shaped openings, a process gas and a radical are rotated inside the process vessel. Thus, it becomes possible to repeatedly introduce them while switching at high speed. As a result, it is possible to efficiently grow a high-quality film by one atomic layer on the surface of the substrate to be processed by performing radical treatment on the processing gas molecules adsorbed on the surface of the substrate to be processed. At that time, a bypass line connected to the exhaust system is provided in the radical source, and in a state where the processing gas is introduced into the processing vessel, the radical is exhausted to the bypass line, and the processing gas molecules that have adsorbed the radical are formed. By configuring the radical to be introduced from the radical source into the processing vessel only when a reaction such as oxidation is performed, a radical source such as remote plasma can be operated continuously and stably, and an atomic layer CVD process is performed. Even when the cycle time is shortened, there is no problem that radical formation becomes unstable. As a result, throughput during substrate processing can be improved.

  In addition, according to the present invention, by using an ultraviolet light source that operates stably even if it is turned on and off as a radical source, an ultraviolet light radical oxidation treatment apparatus used for forming an oxide film on the surface of a silicon substrate can be used to efficiently perform atomic operation. A layer CVD process can be performed.

  Furthermore, according to the present invention, a radical source of the cleaning gas is coupled to a part of an exhaust system connected to an exhaust port for exhausting the processing container, and the radical of the cleaning gas is introduced into the processing container by going back through the exhaust system. By doing so, the inside of the processing container can be efficiently cleaned.

[First Reference Example]
FIG. 7 shows a configuration of a substrate processing apparatus (ALD film forming apparatus) 40 according to a first reference example of the present invention. However, in the figure, the same reference numerals are given to the parts described above, and the description thereof is omitted.

  Referring to FIG. 7, in this reference example, the conductance valves 15A and 15B used in the substrate processing apparatus 10 described in FIGS. 1 to 3 are removed, and instead, adjacent to the exhaust ports 14A and 14B, High speed rotary valves 25A and 25B are provided in the exhaust groove 201a or 201b. Further, the high-speed rotary valves 25A and 25B are coupled to the trap 100 via pipes 207a and 207b, respectively.

  FIG. 8 shows the configuration of the processing vessel 11 with the quartz bottom plate 202A of FIG. 3 removed.

  Referring to FIG. 8, a space for accommodating the quartz reaction vessel 202 is formed in the outer vessel 201 constituting the treatment vessel 11, and the surface of the substrate 12 to be treated is exposed in the space. Further, high-speed rotary valves 25A and 25B having exhaust ports 26A and 26B are provided on both sides of the substrate 12 to be processed instead of the previous exhaust ports 14A and 14B. In the present embodiment, the exhaust ports 26A and 26B have a width W measured in a direction parallel to the flow direction of the raw material gas set substantially larger than that of the conventional exhaust ports 14A and 14B. As a result, a large amount of gas can be efficiently exhausted from the quartz reaction vessel 202 through the exhaust ports 26A and 26B.

  9A and 9B show the configuration of the high-speed rotary valve 25A. However, FIG. 9A is a perspective view of the entire rotary valve 25A as viewed obliquely from above, and FIG. 9B is a perspective view of the same rotary valve 25A as viewed from obliquely below. Since the high-speed rotary valve 25A has the same configuration as the high-speed rotary valve 25B, only the high-speed rotary valve 25A will be described below.

  Referring to FIG. 9A, the high-speed rotary valve 25A includes a main body 251 in which the exhaust port 26A is formed, a valve body 252 (see FIG. 10) provided in the main body 251 so as to be rotatable, A servo motor 253 that rotates the valve body 252 is provided, and a heating unit 254 that houses a heater is provided in a part of the main body 251. Further, as shown in FIG. 9B, an exhaust port 255 coupled to the conduit 207a is formed on the bottom surface of the main body 251.

  FIG. 10 shows an exploded view of the high-speed rotary valve 25A of FIGS. 9 (A) and 9 (B).

  Referring to FIG. 10, one end of the main body 251 is closed by a cap 251A having a bearing, and a driving block 253A having the servo motor 253 is coupled to the other end of the main body 251 through a seal 253B. .

  A cylindrical opening communicating with the exhaust ports 26A and 255 is formed in the main body 251, and a corresponding valve body made of ceramic or metal having a hollow cylindrical shape is formed in the cylindrical opening. 252 is rotatably inserted. The valve body 252 is formed with an opening 252A extending in the length direction and another opening 252B (see FIG. 11) at a position facing the opening 252A in the radial direction. Is coupled to the servo motor 253 at a shaft 252X provided at the end of the valve body 252 and is rotated clockwise and counterclockwise by the servo motor 253. A heater 254A is inserted into the heating unit 254. The other end of the valve body 252 is provided with a rotation shaft similar to the shaft 252X (not shown), and is rotatably held by a bearing provided in the cap 251A.

  11A to 11D show the configuration of the valve body 252. FIG. 11A is a perspective view of the valve body 252, FIG. 11B is a plan view of the valve body 252, FIG. 11C is a cross-sectional view of the valve body 252, and FIG. 11D is a valve body 252. The bottom view of is shown.

  Referring to FIGS. 11A to 11D, the valve body 252 is formed with two openings 252A with an intermediate part 252a therebetween, and each of the openings 252A has the valve body 252. It communicates with an opening 252B formed at a position facing the intermediate portion 252a through an internal space.

  FIGS. 12A, 12B and 12C, 12D show four states of the high-speed rotary valve 25A used in the substrate processing apparatus 40 of this reference example.

  Referring to FIG. 12A, the servo motor 253 rotates the valve body 252 so that the opening 252A in the valve body 252 forms an opening having a width W of 6 mm at the exhaust port 26A. As a result, when the substrate processing apparatus 40 of FIG. 7 is used in the configuration of FIG. 1 and the inside of the quartz reaction vessel 202 is evacuated through the conduit 207a coupled to the opening 255, the conductance at the time of evacuation is increased. The reaction vessel 202 is evacuated gradually and the desired source gas is adsorbed on the surface of the substrate 12 to be processed.

  On the other hand, in the state of FIG. 12B, the valve body 252 is driven by the servo motor 253 so that the opening 252A forms an opening having a width W of 8 mm, and as a result, the valve 25A shown in FIG. It becomes larger than the state of (A).

  In the state of FIG. 13C, the valve body 252 is driven by the servo motor 253 so that the opening 252A coincides with the opening 26A, and as a result, the valve 25A is fully opened. . In the state of FIG. 13C, the opening 252A forms an opening having a width W of 40 mm.

  On the other hand, in the state of FIG. 13D, the valve body 252 is driven by the servo motor 253 so that the opening 252A is completely removed from the opening 26A, and as a result, the valve 25A is closed. It is in a state.

  FIG. 45 shows an example of a change in conductance accompanying the rotation of the valve body 252 in the high-speed rotary valves 25A and 25B according to this reference example.

Referring to FIG. 45, when the rotation angle of the valve body 252 is 0 °, a conductance exceeding 3000 l / sec is obtained, whereas when the rotation angle exceeds about 40 °, the conductance becomes zero. It can be seen that the rotation angle increases again from around 120 ° and increases to a value of about 600 l / sec around 170 °. In the present invention, the conductance change shown in FIG. 45 can be realized in an extremely short time within 0.1 seconds by simply rotating the valve body 252.

[Second Reference Example]
FIG. 14 shows the configuration of a second reference example of the present invention in which an Al ₂ O ₃ film is formed on the surface of the substrate 12 to be processed by the ALD method using the substrate processing apparatus 40 of FIG. However, in FIG. 14, the same reference numerals are given to the parts described above, and the description thereof is omitted.

  Referring to FIG. 14, in this reference example, TMA (trimethylaluminum) is held in the raw material container 20A, and the TMA in the raw material container 20A passes through the switching valve 16A and the nozzle 13A, and the quartz in the processing container 11 is retained. It is introduced into the reaction vessel 202. In the system of FIG. 14, the raw material supply system including the raw material container 20C is not used, and thus illustration is omitted.

  FIG. 15 is a flowchart illustrating an ALD process performed using the system of FIG.

  Referring to FIG. 15, in the process of Step 10, both the high-speed rotary valves 25A and 25B are fully opened to the state shown in FIG. 13C, and the valves 16A and 16B are respectively connected through the nozzles 13A and 13B. Ar gas is introduced into the quartz reaction vessel 202 and the inside of the reaction vessel 202 is purged.

Next, in step 11, the high speed rotary valve 25A is closed to the state shown in FIG. 13D, and at the same time, the high speed rotary valve 25B is partially opened to the state shown in FIG. Alternatively, the high-speed rotary valve 25B is controlled so that the inside of the reaction vessel 202 has a predetermined pressure. Further, H ₂ O gas is introduced into the quartz reaction vessel 202 through the valve 16B and the nozzle 13B. The introduced H ₂ O gas flows in a laminar flow along the surface of the substrate 12 to be processed, and is discharged from the rotary valve 25B. Accordingly, H ₂ O molecules on the substrate surface, it is adsorbed by one molecular layer. During the step 11, a small amount of Ar gas is supplied to the nozzle 13A from the valve 16A, and the inside of the nozzle 13A is purged.

  Next, in step 12, both the high-speed rotary valves 25A and 25B are set to the fully opened state in FIG. 13C, and Ar gas is introduced from the valves 16A and 16B through the nozzles 13A and 13B. The nozzles 13A and 13B and the inside of the quartz reaction vessel 202 are purged.

Next, in step 13, the high-speed rotary valve 25A is partially opened to the state shown in FIG. 12B, and the high-speed rotary valve 25B is further closed to the state shown in FIG. Alternatively, the high-speed rotary valve 25 </ b> A is controlled so that a predetermined pressure is generated inside the processing container 22. Further, in this state, TMA is introduced from the switching valve 16A through the gas nozzle 13A into the quartz reaction vessel 202, and the introduced TMA flows as a laminar flow on the surface of the substrate 12 to be processed, and the rotary valve 25A. Discharged from. As a result, a monomolecular Al ₂ O ₃ film is formed on the surface of the substrate 12 to be processed. During this time, the gas nozzle 13B is purged with Ar gas.

  Further, in the step 14, both the high-speed rotary valves 25A and 25B are fully opened to the state shown in FIG. 13C, and Ar gas is introduced from the nozzles 13A and 13B, so that the inside of the nozzles 13A and 13B and the quartz can be obtained. The inside of the reaction vessel 202 is purged.

By repeating steps 10 to 14, it is possible to form a high-quality Al ₂ O ₃ film on the surface of the substrate to be processed, one molecular layer at a time.

  FIG. 16 shows the purge rate in the quartz reaction vessel 202 in step 10 or 12 of FIG. 15 when the high-speed rotary valves 25A and 25B of the present invention are used and the conventional conductance valves 15A and 15B of FIG. It is a figure shown by comparison with the case.

Referring to FIG. 16, when the high-speed rotary valves 25A and 25B of the present invention are used, the time required for the residual gas concentration to decrease to about 5% of the initial time is about 0.1 seconds. It can be seen that the length is shortened to about 1/5 of the case. In addition, as shown in FIG. 16, even when the quartz reaction vessel 202 is vacuum purged, the residual gas concentration can be reduced to about 5% in 1 second purge time by using the high speed rotary valves 25A and 25B of the present invention. Recognize.

[Third reference example]
FIG. 17 shows a configuration of a substrate processing apparatus 50 according to a third reference example of the present invention. However, in FIG. 17, the same reference numerals are given to the portions described above, and description thereof is omitted.

  Referring to FIG. 17, in this reference example, the high-speed rotary valve 25B on one side is removed, and the corresponding source gas supply nozzle 13B and the source gas supply system cooperating therewith are also removed. .

Also in the substrate processing apparatus 50 having such a configuration, as shown in the flowchart of FIG. 18, in step 21, the high-speed rotary valve 25A is fully opened, and Ar gas is supplied from the nozzle 13A. Is purged at high speed. Therefore the high at step 22 - Set the speed rotary valve 25A to 6mm opening, by further introducing H ₂ O gas from the nozzle 13A, only one molecular layer on the surface of the target substrate 12 H ₂ O Adsorb molecules. In step 22, the same effect can be obtained by setting the processing pressure without setting the opening of the valve 25A and controlling the slit width in accordance with this pressure.

  In step 23, the high-speed rotary valve 25A is fully opened, and the nozzle 13A and the quartz reaction vessel 202 are purged with Ar gas.

Further, in step 24, the high-speed rotary valve 25A is set to an opening of 8 mm, and a TMA gas is further introduced from the nozzle 13A, thereby forming a monomolecular Al ₂ O ₃ film on the surface of the substrate 12 to be processed. Is done. Note that the same effect can be obtained by setting the processing pressure in step 24 without setting the opening of the valve 25A and controlling the slit width in accordance with this pressure.

[First embodiment]
FIG. 19 shows the configuration of the substrate processing apparatus 60 according to the first embodiment of the present invention. In FIG. 19, the same reference numerals are assigned to the portions corresponding to the portions described above, and the description thereof is omitted.

  Referring to FIG. 19, in the substrate processing apparatus 60, the conduit 207b is further provided with the conductance valve 15B of FIG. 2 on the downstream side of the high-speed rotary valve 26B, and the conduit 207b further includes the high-speed rotary valve 26B. A remote plasma source 62 is provided through an opening / closing valve 61 in the middle of the conductance valve 15B.

The remote plasma source 62 is supplied with a rare gas such as Ar and a cleaning gas such as Cl 2 or CHF 3 such as chlorine or fluorine based NF ₃ , and cooperates with the remote plasma source 62, for example, a high frequency source 62A having a frequency of 400 kHz. To generate a chemically active chlorine radical or fluorine radical.

  In this embodiment, in the substrate processing apparatus 60, the high-speed rotary valves 25A and 25B are fully opened, and the conductance valve 15B is further closed, so that the chlorine radicals or fluorine radicals formed in this way are supplied from the conduit 207b. The quartz reaction vessel 202 is introduced through the high-speed rotary valve 25B in the direction opposite to the normal exhaust direction, and further exhausted through the high-speed rotary valve 25A. Cleaning becomes possible.

  FIG. 20 is a flowchart showing the cleaning process of FIG. 19, and FIGS. 21A and 21B are diagrams schematically showing the state of the substrate processing apparatus 60 corresponding to the flowchart of FIG.

Referring to FIG. 20, in step 21, the high speed rotary valve 25A is fully opened and the high speed rotary valve 25B is closed. Further, Ar gas and Cl ₂ gas are supplied to the remote plasma source 62, the conductance valve 15B is fully opened, the open / close valve 61 is opened, and the frequency formed by the high frequency source 62A is 400 kHz. By driving at a high frequency of 5 kW, remote plasma and the accompanying chlorine radical Cl * are generated. In the state of step 21, the formed chlorine radicals are exhausted to the exhaust system as they are, as shown in FIG.

  Next, in Step 22, when the high-speed rotary valve 25B is fully opened and the conductance valve 15 is closed, the chlorine radical Cl * formed in Step 21 is converted into the high-speed rotary valve as shown in FIG. The quartz reaction vessel 202 is introduced through 25B and the exhaust port 26B. The introduced chlorine radical Cl * flows through the quartz reaction vessel 202 to the high-speed rotary valve 25A, and is discharged through the exhaust port 26A. Therefore, by maintaining the state of step 22 for a predetermined time, the deposits adhering to the inner wall surface of the quartz reaction vessel 202 are cleaned.

  Next, in step 23, the high-speed rotary valve 25B is closed again, and the conductance valve 15B is fully opened. As a result, as shown in FIG. 21A, the chlorine radicals formed by the remote radical source 62 are exhausted to the exhaust system as they are.

  Further, in step 24, the high-frequency source 62A is shut off, the remote radical generating source 62 is turned off, and the on-off valve 61 is closed.

In the present embodiment, as described above, the width W of the exhaust ports 26A and 26B is set to be larger than the width of the conventional exhaust ports 14A and 14B, and the high-speed rotary valves 25A and 25B capable of realizing a larger conductance are provided. In combination, when a large amount of radicals are introduced into the quartz reaction vessel 220 from the outside, loss of activity of the radicals can be suppressed to a minimum, and efficient cleaning becomes possible. In the present embodiment, since the radical source 62 is formed in a part of the exhaust system, even if the reaction vessel 202 has a flat shape suitable for forming a laminar flow of the source gas, There is no difficulty in providing a source.

[Second Embodiment]
In the substrate processing apparatus 60 of FIG. 19, the radical source 62 is effective not only for cleaning the processing container 202 but also for oxidizing or nitriding molecules adsorbed on the substrate to be processed. In this case, oxygen or nitrogen gas is supplied to the radical source 62 together with a rare gas such as Ar instead of the cleaning gas.

A substrate processing process according to the second embodiment of the present invention for forming an Al ₂ O ₃ film on a substrate to be processed using the substrate processing apparatus 60 of FIG. 19 will be described with reference to FIGS. 22 (A) and 22 (B). The description will be given with reference.

  Referring to FIG. 22A, the substrate holder 203 is rotated by the servo motor 253, the high-speed rotary valve 25A is opened, and the reaction vessel 202 is evacuated. The remote radical source 62 is driven.

  Further, in the state of FIG. 22A, the high-speed rotary valve 25B is closed, and a processing gas such as TMA is introduced into the reaction vessel 202 from the processing gas inlet 13A. The introduced processing gas flows along the surface of the substrate to be processed on the substrate holding table 203 and is exhausted through the high-speed rotary valve 25A and the conduit 207a. As a result, TMA molecules are adsorbed on the surface of the substrate to be processed, and a TMA layer having a thickness of approximately one molecular layer is formed.

  In the state of FIG. 22A, the variable conductance valve 15C provided in the conduit 207b is opened, and as a result, oxygen radicals formed by the remote radical source 62 are introduced into the reaction vessel 202. Without being discharged through the variable conductance valve 15C.

On the other hand, in the state of FIG. 22 (B), the supply of TMA to the processing gas inlet 13A is shut off by the switching valve 16A, the variable conductance valve 15C is closed, and the high-speed rotary valve 25B is opened. Oxygen radicals O * formed by the remote radical source 62 are supplied into the container 202 in the form of backflow through the exhaust port 26B. At that time, in the state of FIG. 22B, the high-speed rotary valve 25A is also opened, and as a result, the oxygen radical O * introduced in this way is rotated in the reaction vessel 202. TMA molecules flowing along the surface of the substrate and adsorbed on the surface of the substrate are oxidized to form a monomolecular layer of Al ₂ O ₃ film.

After the step of FIG. 22 (B), the process returns to the step of FIG. 22 (A) and the steps of FIG. 22 (A) and FIG. 22 (B) are alternately repeated, so that the Al ₂ O ₃ film is processed. One molecular layer can be grown on top.

Thus, in this embodiment, oxygen radicals are used in place of H ₂ O for the oxidation of TMA molecules. Accordingly, the processing gas supply port 13B for introducing H ₂ O and the switching valve 16B are not used. As a result, the problem of adhesion of H ₂ O molecules on the inner wall of the reaction vessel 202 and the switching valve 16B does not occur, and the purge process at the time of switching from the state of FIG. 22B to the state of FIG. Can be performed quickly.

  In particular, by using the high-speed rotary valves 25A and 25B described above at the exhaust ports 26A and 26B, the remote radical source 62 can be provided in the vicinity of the exhaust port 26B, and oxygen radicals can be efficiently supplied to the reaction vessel. It becomes possible to introduce into 202. In the present embodiment, the remote radical source 62 is not required to be directly provided in the flat processing vessel 201 or the reaction vessel 202 in the inside thereof, so that the design is easy.

  FIG. 23 is a flowchart showing the substrate processing steps by the substrate processing apparatus 60 of FIG. 19 including the steps of FIGS. 22 (A) and 22 (B).

  Referring to FIG. 23, in step S30, the high-speed rotary valves 25A and 25B are fully opened, and Ar gas is introduced from the processing gas inlet 13A, thereby purging the inside of the reaction vessel 202. In this step, the valve 61 is closed as shown in FIG. 24A in order to prevent the residual processing gas discharged from the reaction vessel 202 from entering the remote plasma source 62 and causing deposition. May be. However, when there is little intrusion of the residual processing gas, it is possible to keep the valve 61 open in the purge process of step S30 as shown in FIG. In this case, the pressure in the remote plasma source 62 is stabilized, and the plasma can be stabilized.

  Next, in step S31 corresponding to the step of FIG. 22A, the rotary valve 25B is closed, and the degree of solution of the rotary valve 25A is set to 6 mm. In this state, by introducing TMA from the processing gas inlet 13A, a TMA molecular layer having a thickness of approximately one molecular layer is uniformly adsorbed on the surface of the substrate to be processed.

  Next, in step S32, the high-speed rotary valves 25A and 25B are fully opened again, and the TMA remaining in the reaction vessel 202 is purged. Even at this stage, the bulb 61 of the remote plasma source 62 may be closed as shown in FIG. However, when there is little intrusion of the residual processing gas, it is possible to keep the valve 61 open in the purge process of step S30 as shown in FIG. In this case, the pressure in the remote plasma source 62 is stabilized, and the plasma can be stabilized.

Further, in step S33 corresponding to the step of FIG. 22B, the high-speed rotary valves 25A and 25B are opened, and the introduction of TMA from the processing gas inlet 13A is blocked. Further, by closing the variable conductance valve 15C and opening the valve 61, oxygen radicals are introduced into the reaction vessel 202, and the TMA molecular layer previously adsorbed on the surface of the substrate to be processed is oxidized. As a result, an Al ₂ O ₃ film having a thickness of one molecular layer is formed on the surface of the substrate to be processed.

  Further, in step S34, the high-speed rotary valves 25A and 25B are fully opened, and the reaction vessel 202 is purged while introducing Ar gas from the processing gas inlet 13A. However, in step 34, the variable conductance valve 15C is in an opened state.

Step S34 is the same process as the previous step S30. Therefore, by repeating the subsequent steps 31 to 34, it is possible to grow an Al ₂ O ₃ film on the surface of the substrate to be processed one layer at a time.

  According to this embodiment, by using oxygen radicals for the oxidation of the TMA molecular layer, the purge time in step S10, that is, step S34 can be shortened, and the substrate processing efficiency can be improved.

In the present invention, the film to be formed is not limited to the Al ₂ O ₃ film, but a ZrO ₂ film is formed by using ZrCl ₄ gas, and an HfO ₂ film is formed by using HfCl ₄ gas. Is possible.

  Further, the remote plasma source 62 can be supplied with nitrogen gas to form nitrogen radicals.

  In the present embodiment, the remote plasma source 62 is provided in a part of the exhaust system so that the processing gas is introduced and the surface of the substrate to be processed is covered with processing gas molecules. Even when the source 62 is continuously operated, radicals do not enter into the reaction vessel 202. Therefore, it is not necessary to control the remote plasma source 62 on and off, and even when the substrate processing apparatus is operated in a short cycle. Stable plasma supply is possible. Therefore, the substrate processing apparatus of FIG. 5 can perform a so-called atomic layer CVD process with a large throughput.

  FIG. 25A shows a case where supply of a processing gas such as TMA is performed from the processing gas inlet 13B facing the processing gas inlet 13A in step S31 of FIG.

  In this case, the processing gas introduced from the valve 16B through the processing gas inlet 13B flows through the processing container 202 in the direction of the processing gas inlet 13A, and then passes through the fully opened high-speed rotary valve 25A. Exhaust to the exhaust conduit 207b. At that time, the variable conductance valve 15C provided in the conduit 207b is also fully opened, and as a result, the processing gas is exhausted through the valve 15C.

  In the state shown in FIG. 25A, since the high-concentration processing gas flows through the conduit 207b, the valve 61 of the remote plasma source 62 needs to be closed. Otherwise, a processing gas such as TMA is oxidized by oxygen radicals in the conduit 207b, and deposition occurs.

The state of FIG. 25 (B) is an oxidation process corresponding to step S33 of FIG. 23, and the high-speed rotary valve in which oxygen radicals are fully opened from the remote radical source 62 is the same as in the case of FIG. 22 (B). After being introduced into the processing container 202 through 25B and further flowing along the surface of the substrate to be processed, it is exhausted through the fully-rotated high-speed rotary valve 25A. In this state, the variable conductance valve 15C is closed.

[Third embodiment]
FIG. 26 shows a configuration of a substrate processing apparatus 80 according to the third embodiment of the present invention. However, in the figure, the same reference numerals are given to the parts described above, and the description thereof is omitted. FIG. 26 shows a state in which the sample holder 203 is lifted to the processing position. In the configuration of FIG. 26, the substrate transfer unit 204A is provided so as to be positioned between the high-speed rotary valves 25A and 25B.

  Referring to FIG. 26, the substrate processing apparatus 80 has a configuration substantially corresponding to the substrate processing apparatus 40 described above, but in this embodiment, the quartz reaction vessel 202 corresponds to the substrate 12 to be processed. A flat gas passage having a low height is formed between the substrate to be processed 12 and the quartz reaction vessel 202 in the vicinity of the surface of the substrate to be processed 12. Corresponding to the shape of the quartz reaction vessel 202, the cover plate 201A is also formed in a shape with an increased thickness at the center. Thus, by forming a gas path that is very flat and low in the surface of the substrate 12 to be processed, the flow velocity of the gas passing through the surface of the substrate 12 as a laminar flow increases, and as a result, the substrate to be processed Uniform adsorption of gas phase source molecules on the 12 surface is guaranteed. Further, since the effective volume in the processing vessel 201 is reduced, the purge efficiency is improved, and the atomic layer CVD process can be efficiently performed while switching the processing gas in a short time.

  26, instead of the processing gas inlets 13A and 13B, bird's beak-like processing gas inlets 83A and 83B are provided inside the high-speed rotary valves 25A and 25B, that is, on the side close to the substrate 12 to be processed. Furthermore, a remote plasma source 82 is provided on the cover plate 201A. The remote plasma source 82 is coupled to the high-speed rotary valve 25B by a conduit 85A as described below, and introduces formed oxygen radicals or nitrogen radicals into the processing space in the reaction vessel 202. For this reason, the valve 25B has an exhaust port 255 connected to the exhaust pipe 207b and an inlet 26C to which the conduit 85A is coupled.

  The rotary valve 25A has an exhaust port 26A connected to a side portion of the reaction vessel 202, and exhausts the processing space inside the reaction vessel 202 in accordance with the rotation of the valve body 252 as described below. Similarly, the rotary valve 25 </ b> B has an exhaust port 26 </ b> B coupled to the side portion of the reaction vessel 202, and exhausts the processing space inside the reaction vessel 202 according to the rotation of the valve body 252.

  Also, in the substrate processing apparatus 80 of FIG. 26, a processing gas introduction pipe 25a is formed along the rotation axis of the valve 25A inside the high speed rotary valve 25A, and the processing gas introduction pipe 25a is connected to the switching valve 16B of FIG. It is connected.

  FIG. 27 shows an adsorption process performed in the state 1 of the substrate processing apparatus 80 of FIG.

  Referring to FIG. 27, the high-speed rotary valves 25A, 25B have another large valve opening 252C in addition to the valve opening 252A and the valve opening 252B described above in the valve body 252C. In 25A, the openings 252A to 252C are formed clockwise, and in the valve 25B, the openings 252A to 252C are formed counterclockwise. In this embodiment, the openings 252B and 252C both have an elongated shape extending in the axial direction of the valve body 252 similar to the opening 252A shown in FIG.

  27, the high-speed rotary valve 25B is rotated so that the large opening 252B is aligned with the exhaust port 255. In this state, another large opening 252C is provided in the processing space in the quartz reaction vessel 202. It is aligned with the exhaust port 26B that communicates. Accordingly, the processing space is exhausted to the exhaust pipe 207b through the openings 252C and 252B. In this state, the communication of the bulb 25B to the remote plasma source 85 is blocked, and the communication to the processing gas inlet 83A is also blocked.

  In state 1 of FIG. 27, the high-speed rotary valve 25A is further rotated so that the large opening 252A is aligned with the processing gas introduction port 83B, and a processing gas such as TMA is further supplied from the switching valve 16B to the processing gas introduction pipe 25a. And introduced into the space in the valve 25A. The processing gas thus introduced is introduced into the processing space in the quartz processing vessel 222 through the opening 252A and the processing gas introduction port 83B, and the processing gas is discharged through the exhaust port 26B and the valve 25B. In the meantime, source molecules in the processing gas are adsorbed on the surface of the substrate 12 to be processed.

  FIG. 28 shows state 2 of the substrate processing apparatus 80 in the exhaust process performed subsequent to the process of FIG.

  Referring to FIG. 28, the high-speed rotary valve 25B is rotated so that the large valve opening 252C is aligned with the exhaust port 26B. In this state, another large valve opening 252B is aligned with the exhaust port 255. In addition, the same state occurs in the high-speed rotary valve 25A. As a result, the processing space inside the quartz reaction vessel 202 is quickly exhausted through the high-speed rotary valves 25A and 25B.

  FIG. 29 shows an enlarged view of the vicinity of the high speed rotary valve 25B in the exhaust process of FIG.

  Referring to FIG. 29, in this embodiment, as described above, the processing gas inlet 83A is formed at a position closer to the substrate 12 to be processed than the high speed rotary valve 25B. Therefore, in the exhaust process of FIG. 28, the processing gas introduction port 83A is positioned upstream of the gas flow to be exhausted with respect to the high-speed rotary valve 25B, and the gas flow enters the exhaust port 26 to form a bird's beak-like processing gas introduction port 83A. And flows into the valve 25B through the valve opening 252C. For this reason, the stagnation of gas that was likely to occur in the region indicated by the broken line behind the gas inlet is eliminated, and the inside of the reaction vessel 202 can be efficiently exhausted.

  28 and 29, the oxidation process shown in FIG. 30 is performed in the state 3 of the substrate processing apparatus 80.

  Referring to FIG. 30, in the oxidation process, Ar gas and oxygen gas are supplied to the remote plasma source 85, and oxygen radicals O * are formed by exciting them at a high frequency of, for example, 400 kHz. Further, in the process of FIG. 30, the high-speed rotary valve 25B is rotated so that the valve opening 252B is aligned with the opening 26C, and in this state, the valve opening 252A is aligned with the exhaust port 26B.

  As a result, the oxygen radical O * excited by the remote plasma source 85 is introduced into the processing space in the quartz processing vessel 202 through the valve opening 252A and the exhaust port 26B in the reverse direction. At this time, the high-speed rotary valve 25A is set at the same exhaust position as in FIG. 28. As a result, oxygen radicals introduced through the high-speed rotary valve 25B and the processing gas introduction port 83A pass through the processing vessel 202. It flows along the surface of the processing substrate 12 to the exhaust port 26A of the high-speed rotary valve 25A, during which the source molecules previously adsorbed on the processing substrate 12 are oxidized. At that time, by reducing the valve opening 252A as a large-area opening and introducing radicals through the exhaust port 26B, it is possible to avoid a reduction in radical lifetime.

  Further, after the process of FIG. 30, the exhaust process of FIG. 28 is performed, and the adsorption process of FIG. 27, the exhaust process of FIG. 28, the oxidation process of FIG. 30 and the exhaust process of FIG. A high dielectric film made of a metal oxide or the like is laminated one by one.

  FIG. 31 shows an example of a substrate processing process using the substrate processing apparatus 80 of FIG.

  Referring to FIG. 31, in step 41, the substrate processing apparatus 80 is set to the state 2 of FIG. 28, and the processing space inside the reaction vessel 202 is exhausted. At this time, Ar gas is introduced from the processing gas inlet 83A, thereby purging the processing gas inlet 83A and the processing space.

  Next, in step 42, the substrate processing apparatus 80 is set to state 1 in FIG. 27, and a processing gas such as TMA is introduced into the reaction vessel 202 from the processing gas inlet 83 </ b> B. Adsorption occurs.

  Next, in step 43, the substrate processing apparatus 80 is returned to the state 2 of FIG. 28, and the processing space inside the reaction vessel 202 is exhausted. At that time, in the step 43, Ar purge gas is introduced from the processing gas inlet 83B, and the processing gas inlet 83B and the processing space are purged.

  Next, in step 44, the substrate processing apparatus 80 is set to the state 3 of FIG. 30, and radicals such as oxygen radicals formed by the radical source 85 pass through the high-speed rotary valve 25B and the exhaust port 26B to the processing space. Then, the source molecules previously adsorbed on the substrate 12 to be processed are oxidized.

Further, the process returns to Step 41, and Steps 42 to 44 are repeated, whereby an Al ₂ O ₃ film is formed on the surface of the substrate to be processed 12 by one molecular layer.

  FIG. 32 is a partially cut cross-sectional view of the substrate processing apparatus 80 according to this embodiment described above with the cover plate 201A opened.

  Referring to FIG. 32, the gas introduction pipe 25a extends in the axial direction in the high-speed rotary valve 25A, and the opening 26C has a substantially circular shape corresponding to the shape of the conduit 85A. It can be seen that the valve openings 252A, 252B or 252C have an elongated shape extending in the axial direction of the valve body 252. In addition, a connecting portion 25a1 of a raw material gas pipe is provided at the end portion of the gas introduction pipe 25a, and it can be seen that the valve body 252 is driven by a motor 253 in both the valves 25A and 25B.

As shown in FIG. 32, the cover plate 201A is provided so as to be freely opened and closed by a fulcrum that is not shown. However, the substrate processing apparatus 80 can be easily maintained by such a configuration.

[Fourth Reference Example]
FIG. 33 shows a configuration of a substrate processing apparatus 90 according to a fourth reference example of the present invention, and FIG. 34 shows a configuration of a processing gas inlet used in the substrate processing apparatus 90 of FIG. However, in FIGS. 33 and 34, portions corresponding to the portions described above are denoted by the same reference numerals, and description thereof is omitted. FIG. 33 shows a state in which the substrate holder 203 is lowered to a position corresponding to the substrate loading / unloading port 204A, and the substrate 12 to be processed is lifted by the lifter pins 204B.

Referring to FIG. 33, the substrate processing apparatus 90 has the same configuration as that of the substrate processing apparatus 80 according to the previous embodiment. However, as shown in FIG. Connected. For example, in the case of the processing gas introduction port 83A, the Ar purge gas supplied via the line 23a and the valve 24A and the source gas such as ZrCl ₂ and TMA supplied via the line 16a and the valve 19A in FIG. The Ar purge gas supplied via the line 23c and the valve 24C and the source gas such as ZrCl ₂ and TMA supplied via the line 16c and the valve 19C are supplied via the switching valve 16C. Have been supplied.

  33 does not include the remote plasma source 85 used in the substrate processing apparatus 80.

  FIG. 35A shows in detail the configuration of the high-speed rotary valves 25A and 25B used in the substrate processing apparatus 90 of FIG. 33, particularly the configuration of the valve body 252 used in each valve.

  Referring to FIG. 35 (A), the high-speed rotary valves 25A and 25B are formed with valve openings (1) to (3) corresponding to the valve openings 252A and 252B described above. B) shows a developed view of the valve body 252 formed with the valve openings (1) to (3) in the valve 25A. Similarly, FIG. 35C shows a development view of the valve body 252 formed with the valve openings (1) to (3) in the valve 25B.

  Referring to FIGS. 35B and 35C, the openings (1) to (3) of the valve 25B are in the state shown in FIG. The position and width are set so that the opening (3) communicates with the exhaust pipe 207a via the exhaust port 255 so that the opening (2) communicates with the processing gas introduction port 83A. In the valve 25A, the openings (1) to (3) are similarly formed.

In this reference example, ozone gas (O ₃ ) is supplied to the processing gas inlet 83A via the line 16a and the valve 19A, and further, for example, Hf [N ( Hf organometallic raw materials such as C ₂ H ₅ ) ₂ ] ₄ or Hf [N (CH ₃ ) ₂ ] ₄ are supplied.

  Next, an example of a substrate processing process performed using the substrate processing apparatus 90 of FIG. 33 will be described with reference to FIGS. 36 (A) to (D) and FIGS. 37 (E) to (H).

  36A, the high-speed rotary valves 25A and 25B are set to the state shown in FIG. 35A. As a result, the processing space inside the quartz processing vessel 202 is opened in both the valves 25A and 25B. The exhaust pipe 270a or 207b is exhausted by a route passing through the sections (1) and (3). In the state of FIG. 36A, the opening (2) is aligned with the processing gas introduction port 83A or 83B in either of the valves 25A and 25B. As a result, the processing gas introduction ports 83A and 83B are also opened (3). And exhausted through the exhaust pipe 207a or 207b.

  Next, in the process of FIG. 36 (B), the state of the high-speed rotary valve 25B remains as shown in FIG. 36 (A), but the valve body 252 of the high-speed rotary valve 25A communicates with the opening (1) to the exhaust pipe 207a. Any of the openings (2) to (3) is rotated to a position not communicating with the processing space or the processing gas introduction port 83B, the valve 19B is opened, and the organometallic Hf raw material in the line 16b becomes the processing gas introduction port. It is introduced into the processing space via 83B. The introduced organometallic Hf raw material flows in the processing space along the surface of the substrate to be processed 12 and is adsorbed on the surface of the substrate to be processed 12.

  Next, in the step of FIG. 36C, the valve body 252 in the high-speed rotary valve 25B is returned to the position in FIG. 36A while maintaining the position of the valve body 252 in the high-speed rotary valve 25A. The processing space inside the container 202 is exhausted to the exhaust pipe 207b. In the step of FIG. 36C, the valve 24B is opened, and the Ar purge gas in the line 23b is introduced into the processing gas inlet 83B. As a result, the processing gas inlet 83B is purged.

  Further, in the step of FIG. 36D, the valve body 252 in the high speed rotary valve 25A is returned to the state of FIG. 36A, and the processing space inside the processing container 202 becomes the opening (1) of the high speed rotary valve 25A. ), (2) and (3) are exhausted to the exhaust pipe 207a. In the step of FIG. 35D, the valve 24A is opened, and the Ar purge gas in the line 23a is introduced into the processing gas inlet 83A. As a result, the processing gas inlet 83A is purged.

  Next, in the step of FIG. 37 (E), the valve bodies 252 in the high-speed rotary valves 25A and 25B are all returned to the state of FIG. 36 (A), and the processing space inside the processing container 202 is exhausted.

Next, in the step of FIG. 37 (F), the valve body 252 of the high speed rotary valve 25A remains in the state of FIG. 37 (E), and the valve body 252 in the high speed rotary valve 25B is in the same position as FIG. 36 (D). Further, the valve 19A is opened, and the ozone gas in the line 16a is introduced into the processing space through the processing gas inlet 83A. The introduced ozone gas flows in the processing space along the surface of the substrate 12 to be processed, oxidizes the organometallic Hf source molecules adsorbed on the surface of the substrate 12 to be processed, and forms an HfO ₂ film having a thickness of one molecular layer. Form.

  Next, in the step of FIG. 37 (G), the position of the valve body 252 in the high-speed rotary valves 25A and 25B is held as it is, and the processing space inside the processing container 202 is exhausted to the exhaust pipe 207a. In the step of FIG. 37G, the valve 24A is opened, and the Ar purge gas in the line 23a is introduced into the processing gas introduction port 83A. As a result, the processing gas introduction port 83A is purged.

  37 (H), the valve body 252 in the high-speed rotary valve 25A is returned to the state shown in FIG. 36 (A), and the opening (1) communicates with the exhaust pipe 207b. Communicates with the processing gas inlet 83A and the opening (3) communicates with the processing space. As a result, the processing space inside the processing container 202 is exhausted from the opening (2) or (3) to the exhaust pipe 207b through the opening (1). In the step of FIG. 37H, the valve 24B is opened, and the Ar purge gas in the line 23b is introduced into the processing gas introduction port 83B. As a result, the processing gas introduction port 83B is purged.

Further, by repeating the steps of FIGS. 36A to 37H, the atomic layer growth of the HfO ₂ film is realized on the substrate 12 to be processed.

  Note that in this reference example, the nozzle purge step shown in FIG. 38A may be performed after the step of FIG. 36B and before the step of FIG. 37F. Further, after the step of FIG. 37F, the nozzle purge step shown in FIG. 38B may be performed before the step of FIG. 36B in the next cycle.

  38A, in the high-speed rotary valve 25B, the valve body 252 is rotated to a position where none of the openings (1) to (3) communicates with the processing space in the processing container 202. Further, in the high-speed rotary valve 25A, the valve body 252 is set at the position shown in FIG.

  When the valve 24B is opened in this state, Ar gas in the purge line 23b is introduced into the processing gas introduction port 83B. The introduced Ar gas is treated in the processing gas introduction port 83B by the action of the high-speed rotary valve 25A. The gas flows in the direction opposite to the normal gas flow direction in the gas inlet 83B, and is discharged to the exhaust pipe 207a through the openings (2) and (3).

  In the example of FIG. 38B, in the high-speed rotary valve 25A, the valve body 252 is rotated to a position where none of the openings (1) to (3) communicates with the processing space in the processing container 202. In the high-speed rotary valve 25B, the valve body 252 is set at the position shown in FIG.

  When the valve 24A is opened in this state, the Ar gas in the purge line 23a is introduced into the processing gas introduction port 83A. The introduced Ar gas passes through the processing gas introduction port 83A by the action of the high-speed rotary valve 25B. It flows in the direction opposite to the normal gas flow direction in the inlet 83A, and is discharged to the exhaust pipe 207b through the openings (2) and (3).

  FIG. 39 is a diagram showing the characteristics of the purging process of the processing gas inlet 83A or 83B in FIGS. 38 (A) and 38 (B).

  Referring to FIG. 39, the purge gas flows from the region having a small conductance to the large region by flowing the purge gas through the processing gas inlet 83A in the direction opposite to the normal gas flow direction. As a result, the processing gas inlet 83A is efficiently purged. In FIG. 39, a small arrow schematically shows a region having a small conductance, and a large arrow schematically shows a region having a large conductance.

The nozzle reverse purge step shown in FIG. 39 can also be performed by, for example, opening the valve 24A for the processing gas introduction port 83A and introducing Ar gas in the step of FIG. Similarly, the nozzle reverse purge step of FIG. 39 can also be performed by opening the valve 24B for the processing gas introduction port 83B and introducing Ar gas in the step of FIG. 37 (G).

[Fourth embodiment]
40A to 40C show a schematic configuration of a substrate processing apparatus 120 according to the fourth embodiment of the present invention. However, in the figure, the same reference numerals are given to the parts described above, and the description thereof is omitted.

  Referring to FIG. 40A, the substrate processing apparatus 120 has a configuration similar to that of the substrate processing apparatus 100 described above, but the remote plasma source 85 described in the substrate processing apparatus 80 of FIG. However, it is different in that it is connected via a conduit 85A. As in the embodiment of FIG. 27 or 32, the remote plasma source 85 is provided on a cover plate 201A that can be freely opened and closed. Ar gas is supplied from the line 86a through the valve 86A and from the line 86b through the valve 86B. Oxygen gas is supplied. In this embodiment, an organic metal Hf raw material is supplied from the line 16a to the processing gas supply port 83A through the valve 19A instead of ozone gas.

  As shown in FIG. 40 (A), the high-speed rotary valves 25A and 25B are shown in detail in the developed view of FIG. 40 (B) or FIG. 40 (C) as valve openings 252A and 252B on the respective valve bodies 252. Openings (1) to (3) are formed. More specifically, in the developed view of FIG. 40 (B) corresponding to the high-speed rotary valve 25B, the openings (1) to (3) have the opening (1) at the end of the processing vessel 202. The opening (2) is in communication with the gas nozzle 83A and the opening (3) is in communication with the exhaust pipe 207b. In the illustrated example, the opening (3) is formed in a circular or elliptical opening shape, but all of these opening portions (1) to (3) may be formed in a slit shape. .

  On the other hand, in the developed view of FIG. 40C corresponding to the high-speed rotary valve 25A, the openings (1) to (3) need to be able to communicate with the radical source 85, and therefore the arrangement is shown in FIG. (B) is slightly different.

  That is, in FIG. 40C, the openings (1) to (3) are formed in a state where the opening (1) communicates with the end of the processing vessel 202 on the high-speed rotary valve 25A side. The portion (2) communicates with the exhaust pipe 207a, and the opening (2) communicates with the radical source 85 with the opening (3) communicating with the end of the processing vessel 202. Is formed.

  In this embodiment, only the source gas is supplied to the gas nozzle 83B, and no oxidizing gas is supplied. Therefore, it is not necessary to purge the gas nozzle 83B in the reverse direction as in the previous reference example. However, when the width of the opening (1) is set large and the opening (1) communicates with the end of the processing vessel 202, the opening (1) communicates with the gas nozzle 83B. It can also be configured. In this state, the opening (3) communicates with the exhaust pipe 207a. In the configuration of FIG. 40C, the openings (1) and (2) are formed in a slit shape, and the opening (3) is formed in a circle or an ellipse. It is also possible to form all of 3) in a slit shape.

Hereinafter, the HfO ₂ film forming process using the substrate processing apparatus 120 of FIGS. 40A to 40C will be described with reference to FIGS. 41A to 41D and FIGS. 42E to 42H. explain.

  Referring to FIG. 41A, the high-speed rotary valves 25A and 25B are at the positions described above with reference to FIG. 36A, and the processing space in the processing container 202 is exhausted.

  Next, in the step shown in FIG. 41B, the valve body 252 in the high speed rotary valve 25B is connected to the exhaust pipe 207b while the high speed rotary valve 25A is held in the state shown in FIG. Although communicating, both the openings (2) and (3) are rotated to a position where they do not communicate with the processing space. In this state, the valve 19A is opened, and the organic metal Hf raw material is introduced into the processing space from the processing gas inlet 83A.

  The organometallic Hf raw material thus introduced flows through the processing space along the surface of the substrate 12 to be processed to the high-speed rotary valve 25A, and the organic metal Hf raw material molecules are adsorbed on the surface of the substrate 12 to be processed. . Excess source gas is exhausted from the opening (1) of the high-speed rotary valve 25A through the opening (2) to the exhaust pipe 207a.

  Next, in the process of FIG. 41C, the high-speed rotary valve 25A is held in the state shown in FIGS. 41A and 41B, and the high-speed rotary valve 25B is kept as it is. The valve 24A is closed and opened. As a result, Ar gas in the line 23a is introduced into the processing gas inlet 83A, and the introduced Ar gas flows through the processing space along the surface of the substrate 12 to be processed to the high-speed rotary valve 25A. The gas is discharged from the opening (1) of 25A through the opening (2) to the exhaust port 207a. As a result, the processing gas inlet 83A is purged.

  Next, in the step of FIG. 41 (D), the high speed rotary valve 25B is returned to the state of FIG. 41 (A), and the valve body 252 in the high speed rotary valve 25A is further provided with an opening (1 ) Communicates with the exhaust pipe 207a via the exhaust port 255, and the opening (3) rotates so as to communicate with the conduit 85A of the remote plasma source 85. At the same time, the valve 86A is opened, and Ar gas in the line 86a is supplied to the remote plasma source 85.

  Further, in the step of FIG. 41D, the valve 24B is also opened, Ar gas in the purge line 24b is supplied to the processing gas supply port 83B, and the processing gas supply port 83B is purged. Ar gas introduced from the processing gas inlet 83B flows into the high-speed rotary valve 25B through the processing space, and from the opening (1) or the opening (2) to the exhaust pipe 207b through the opening (3). Discharged.

  Next, in the step of FIG. 42E, the state of the high-speed rotary valve 25B is left as it is, and the valve body 252 in the high-speed rotary valve 25A has an opening (2) formed on the valve body 252 as a remote plasma source. The opening (3) is rotated so as to communicate with the 85 conduit 85A and to communicate with the processing space. As a result, Ar gas containing Ar radicals activated by the remote plasma source 85 passes through the openings (2) and (3) and is introduced into the processing space.

Next, in the step of FIG. 42 (F), the high-speed rotary valve 25B is left as it is, and the high-speed rotary valve 25A is also left as it is, the valve 86B is opened in addition to the valve 86A, and the oxygen gas in the line 86b is It is introduced into the remote plasma source 85 together with the Ar gas in 86a and activated. As a result of the activation of oxygen gas in the remote plasma source 85, oxygen radicals O * are formed in the remote plasma source 85, and the formed oxygen radicals O * are opened from the opening (2) to the opening in the high-speed rotary valve 25A. It is introduced into the processing space through (3). The formed oxygen radicals O * flow along the surface of the substrate 12 to be processed, and oxidize the raw material molecules adsorbed on the surface of the substrate 12. As a result, a monomolecular layer of HfO ₂ film is formed on the surface of the substrate 12 to be processed.

  Next, in the process of FIG. 42G, the valve 86B is closed, the plasma source 85 is stopped, the Ar gas is allowed to flow for a predetermined time, and the valve 86A is also closed while the high-speed rotary valves 25A and 25B remain in the same state.

  Further, in the step of FIG. 42 (H), the state of the high speed rotary valve 25A is returned to the state of FIG. 41 (A), and the high speed rotary valve 25B is set to the state of FIG. 41 (B). Further, in this state, by opening the valve 24A, Ar gas is introduced into the processing gas inlet 83A from the purge line 23a, and the processing gas inlet 83A is purged.

Further, by repeating the steps of FIGS. 41A to 42H, an HfO ₂ film is formed on the surface of the substrate 12 to be processed, one molecular layer at a time.

According to the present embodiment, by mixing organic metal source molecules such as Hf adsorbed on the substrate to be processed with oxygen radicals having strong oxidizing power, 1% of C is mixed into the formed film. The following can be suppressed. In addition, the oxidant can be prevented from adhering to the surface of the processing vessel 202 as compared with the case of using another oxidant such as H ₂ O or O _2, and the process gas can be effectively replaced by a simple purge. As a result, the processing throughput of the ALD process is improved. Further, since oxygen radicals are used for the oxidation of the raw material molecules, the time required for the oxidation treatment can be shortened, and the substrate processing throughput can be further improved.

Also in this embodiment, the nozzle reverse purge process described above with reference to FIG. 39 can be performed.

[Fifth embodiment]
FIG. 43 shows a configuration of a substrate processing apparatus 140 according to the fifth embodiment of the present invention. However, in the figure, the same reference numerals are assigned to portions corresponding to the portions described above, and description thereof is omitted.

  43, the substrate processing apparatus 140 has a configuration similar to that of the substrate processing apparatus 40 described above with reference to FIG. 7, but instead of the processing gas inlets 13A and 13B, a quartz nozzle 143A shown in FIG. , 143B. The cover plate 201A has an opening 201a having a quartz window 144 corresponding to the quartz nozzle 143A, and an ultraviolet light source 145 corresponding to the opening 201a is formed on the cover plate 201A. Has been.

  Referring to FIG. 44, the quartz nozzles 143A and 143B have flattened tips, and the conductance gradually decreases toward the slit-like opening on the gas discharge side. By using the nozzle configured as described above, the processing gas is supplied to the processing space in the form of a desired sheet-like uniform laminar flow. This structure is basically called a bird's beak type gas nozzle. The space inside the gas nozzle is an integrated space, and only the cross-sectional area in the gas discharge direction is reduced toward the discharge side. have.

  Therefore, in the configuration of FIG. 43, when oxygen gas is supplied to the quartz nozzle 143A and the ultraviolet light source 145 is driven in this state, the processing gas in the quartz nozzle 143A is excited and oxygen radicals O * are formed.

  Therefore, by oxidizing the raw material molecules such as organometallic Hf adsorbed on the surface of the substrate 12 to be processed by the oxygen radical O * thus formed, a high-quality film with less C contamination can be formed in one molecular layer. It becomes possible to form in thickness.

In addition, in the quartz nozzles 143A and 143B of FIG. 44, the excitation of radicals is promoted by providing a hot filament in the internal gas passage, or by covering the wall surface of the internal gas passage with an Al ₂ O ₃ film or a TiO ₂ film. It is also possible.

[Sixth embodiment]
Next, the substrate processing apparatus 150 according to the sixth embodiment of the present invention in which the gap G between the quartz reaction vessel 202 and the bottom plate 202A, and hence the surface of the substrate to be processed 12 is optimized in the substrate processing apparatus 80 of FIG. This will be described with reference to FIG.

  Referring to FIG. 46, this embodiment optimizes the utilization efficiency of the raw material gas supplied to the processing space in the quartz reaction vessel 202 by optimizing the gap G, thereby operating the substrate processing apparatus. The challenge is to reduce costs.

  FIG. 47 is an enlarged view of a portion including the quartz reaction vessel 202 and the substrate 12 in the substrate processing apparatus 150 of FIG. However, FIGS. 46 and 47 show a state in which the surface of the substrate 12 to be processed is located at a processing position that is flush with the quartz bottom plate 202A.

  Referring to FIG. 47, in such a structure, when a processing gas flow F such as TMA supplied from the nozzle 83A is passed through a narrow space between the quartz reaction vessel 202 and the substrate 12 to be processed, A boundary layer B is formed on the surface of the processing substrate 12 and the surface of the quartz reaction vessel 202, and the processing gas molecules such as TMA molecules transported on the carrier gas in the processing gas flow F are bound to the boundary layer B. It reaches the surface of the substrate 12 by diffusing inside.

  The thickness δ of the boundary layer B varies depending on the flow rate of the TMA gas flow F, and the thickness δ increases as the flow rate decreases and decreases as the flow rate increases. When the thickness δ of the boundary layer B decreases, the time until the TMA molecules released from the TMA gas flow F diffuse in the boundary layer B and reach the surface of the substrate 12 to be processed is shortened. More TMA molecules reach the surface of the substrate 12 to be processed with time. As a result, the utilization efficiency of the raw material is improved.

  The flow rate of the TMA gas flow F can be increased by reducing the height of the process space, that is, the gap G.

  FIG. 48 shows the relationship between such a gap G and the TMA gas supply time until the surface of the substrate 12 to be processed is saturated with TMA molecules. However, in FIG. 48, the horizontal axis indicates the volume of the processing space in the quartz reaction vessel 202, but the diameter of the processing space is kept the same, so the volume of the processing space corresponds to the cap G. . On the other hand, in FIG. 48, the vertical axis indicates the supply time of the TMA gas until the surface of the substrate to be processed is saturated with the adsorbed TMA molecules. The adsorption rate indicating the proportion of the TMA gas adsorbed on the substrate surface increases.

  FIG. 48 shows a simulation result when the bubbler temperature of TMA is set to 25 ° C. and the vapor pressure is set to 1.5 kPa (11 Torr), but when the gap G is 40 mm, the adsorption rate of TMA molecules is 13%. On the other hand, when the gap G is 20 mm, the adsorption rate is improved to 14%. Further, when the gap G is reduced to 8 mm, the adsorption rate is improved to 30%. In FIG. 48, (1) indicates the ratio of TMA molecules adsorbed on the substrate 12 to be processed, and (2) indicates the ratio of TMA molecules discharged without being adsorbed on the substrate 12 to be processed.

  As described above, by reducing the gap G, the thickness δ of the boundary layer B formed on the surface of the substrate 12 to be processed in the process space is reduced, and the adsorption rate is improved. It is confirmed that the utilization efficiency of the raw material gas is improved.

  On the other hand, when the gap G is further reduced and set to about 0.5 to 1.0 mm, if the evacuation performance is sufficiently high, the flow rate of the raw material gas reaches the sonic speed, so that the higher speed Cannot be achieved. Alternatively, when the evacuation performance is insufficient, the gas flow rate is similarly reduced. Therefore, although depending on the evacuation performance, for the gap reduction to about 0.5 to 1.0 mm, there is usually an increase in the flow velocity of the raw material gas, so that the width of the boundary layer is shortened. The diffusion of the raw material gas is increased and the efficiency of adsorption is increased. On the other hand, further reduction of the gap cannot provide such an improvement in raw material utilization efficiency.

From such a situation, it is considered that the height G of the flat process space is preferably set in the range of 0.5 to 8 mm, more preferably 0.5 to 3.5 mm.

[Fifth Reference Example]
49A and 49B show in detail the configuration in the vicinity of the processing gas inlet 83B used in the substrate processing apparatus 90 of FIG. A similar configuration is used for the processing gas introduction port 83A, but the description of the processing gas introduction port 83A is omitted.

  Referring to FIG. 49A, the processing gas introduction port 83A communicates with the high-speed rotary valve 25A through a cylindrical space 83C formed in a part of the processing container, and the cylindrical space 83C. As shown in FIG. 49B, a pipe 83D having a large number of fine openings 83d is inserted.

  Purge gas or raw material gas is supplied into the pipe 83D through the valve 19B or 24B. The supplied gas flows out from the opening 83d into the space 83C, and the outflowed gas flows into the space 83C. To the process space in the quartz reaction vessel 202 from the bird's beak-shaped nozzle 83B.

  FIG. 50 is a plan view of the configuration of FIG. 49A.

  Referring to FIG. 50, the opening 83d is formed in the pipe 83D in a direction opposite to the nozzle 83B, and as a result, the gas flowing out through the opening 83d flows into the cylindrical space. A uniform laminar flow is obtained from the nozzle 83B with no fluctuation in flow rate in the axial direction of the pipe 83D.

In the above description, the present invention has been described by taking the formation of an HfO ₂ film or an Al ₂ O ₃ film as an example. However, the present invention is not limited to such a specific type of film formation, and a ZrO ₂ film, an HfSiO ₄ film, and the like. It can be applied to the formation of various films such as a ZrSiO ₄ film and a Ta ₂ O ₅ film.

  The substrate processing apparatus and the processing method of the present invention described above are very useful in a so-called ALD process in which a film is laminated on a surface of a substrate to be processed, but is limited to atomic layer growth such as MOCVD. This is also effective for a film forming process that is not performed.

  When operating the substrate processing apparatus having the high-speed rotary valves 25A and 25B described above, a waiting time of usually 5 minutes or more may occur between the work of one lot and the work of the next lot. is there.

  As described above, in the high-speed rotary valve 25A or 25B, the valve body 252 is repeatedly rotated at a high speed back and forth within a predetermined angle range, for example, in the range of 0 ° to 90 °, and thus the bearing portion is asymmetric. Wear is likely to occur.

  In order to avoid this problem, when operating the substrate processing apparatus of the present invention, the valve body 252 is continuously rotated at a low speed of 100 RPM or less, preferably about 10 RPM during the standby time. Is preferred.

  In such an idling state of the substrate processing apparatus, the inside of the processing container 201 is preferably evacuated, and the substrate holding table 203 is preferably held at the lowered transfer position (home position). Further, it is preferable that the substrate holder 203 is maintained at a normal process execution temperature, for example, 400 ° C. in preparation for the resumption of the process, and the purge gas is allowed to flow at a low flow rate inside the processing vessel 201.

  While the present invention has been described with reference to preferred embodiments and reference examples, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the spirit and scope of the claims. is there.

It is a figure which shows the outline | summary of the conventional ALD film-forming apparatus. It is a figure which shows the structure of the processing container used with the ALD film-forming apparatus of FIG. It is a figure which shows a part of processing container of FIG. 2 in detail. It is a flowchart which shows the example of the ALD process performed using the ALD apparatus of FIG. It is a figure which shows the ALD process performed in the processing container of FIG. FIG. 3 is another diagram showing an ALD process performed in the processing container of FIG. 2. It is a figure which shows the structure of the processing container used with the ALD film-forming apparatus by the 1st reference example of this invention. It is a perspective view which shows the structure of the processing container of FIG. (A), (B) is a perspective view which shows the structure of the high-speed rotary valve used in the processing container of FIG. It is an exploded view which shows the structure of the said high speed rotary valve. (A)-(D) are figures which show the structure of the valve body used with the said high-speed rotary valve. (A), (B) is a figure (the 1) explaining operation | movement of the said high speed rotary valve. (C), (D) is a figure (the 2) explaining operation | movement of the said high speed rotary valve. It is a figure which shows the outline | summary of the ALD film-forming apparatus by the 2nd reference example of this invention. It is a flowchart which shows the ALD film-forming process by the 2nd reference example of this invention using the ALD film-forming apparatus of FIG. It is a figure which shows the operating characteristic of the high-speed rotary valve of this invention. It is a figure which shows the structure of the ALD film-forming apparatus by the 3rd reference example of this invention. It is a figure which shows the ALD film-forming process by the 3rd reference example of this invention using the film-forming apparatus of FIG. It is a figure which shows the structure of the ALD film-forming apparatus by 1st Example of this invention. 3 is a flowchart illustrating a film forming apparatus cleaning method according to a first embodiment of the present invention. (A), (B) is a figure which shows the cleaning process by 1st Example of this invention corresponding to FIG. (A), (B) is a figure which shows the structure and process of the film-forming apparatus by 2nd Example of this invention. It is a flowchart which shows the film-forming process using the film-forming apparatus of FIG. (A), (B) is a figure which shows the modification of 2nd Example. (A), (B) is a figure which shows another modification of 2nd Example. It is a figure which shows the structure of the film-forming apparatus by 3rd Example of this invention. It is a figure which shows the film-forming process using the film-forming apparatus of FIG. It is another figure which shows the film-forming process using the film-forming apparatus of FIG. It is a figure which expands and shows a part of FIG. FIG. 27 is still another diagram showing a film forming process using the film forming apparatus of FIG. 26. It is a flowchart which shows the film-forming process using the film-forming apparatus of FIG. FIG. 27 is a partially cut perspective view showing the entire film forming apparatus of FIG. 26. It is a figure which shows the structure of the film-forming apparatus by the 4th reference example of this invention. It is a figure which shows the structure of the process gas inlet used by the film-forming apparatus of FIG. (A)-(C) is a figure explaining the high-speed rotary valve used with the film-forming apparatus of FIG. (A)-(D) are figures (the 1) which show the film-forming process performed using the film-forming apparatus of FIG. (E)-(H) is a figure (the 2) which shows the film-forming process performed using the film-forming apparatus of FIG. (A), (B) is a figure which shows the modification of a 4th reference example. It is a figure explaining the modification of FIG. (A)-(C) are figures which show the structure of the film-forming apparatus by 4th Example of this invention. (A)-(D) are figures (the 1) which show the film-forming process performed using the film-forming apparatus of FIG. (E)-(H) are the figures (the 2) which show the film-forming process performed using the film-forming apparatus of FIG. It is a figure which shows the structure of the film-forming apparatus by 5th Example of this invention. It is a figure which shows the structure of the nozzle used in the Example of FIG. It is a figure which shows the example of an operating characteristic of the high-speed rotary valve of this invention. It is a figure which shows the structure of the film-forming apparatus by 6th Example of this invention. It is a figure explaining operation | movement of the film-forming apparatus of FIG. It is another figure explaining operation | movement of the film-forming apparatus of FIG. (A), (B) is a figure which shows a part of film-forming apparatus by the 5th reference example of this invention. It is another figure which shows a part of film-forming apparatus by the 5th reference example of this invention.

Explanation of symbols

10, 40, 50, 60, 80, 90, 120, 140 Substrate processing apparatus 12 Substrate 13A, 13B, 13C, 13D, 83A, 83B, 143A, 143B Processing gas inlet 14A, 14B, 14C, 14D Exhaust port 16A, 16B, 16C Switching valve 15A, 15B Conductance valve 10A Control device 11 Processing vessel 11W Quartz window 16a First processing gas supply line 16b Second processing gas supply line 16c Third processing gas supply line 17A, 17B, 17C , 21A, 22A, 21B, 22B, 21C, 22C Valve 18A, 18B, 18C, 20a, 20c Mass flow controller 21a, 21b, 21c, 23a, 23b, 23c, 100a, 100b Purge line 20A, 20B, 20C Raw material container 25A , 25B high Rotary valve 26A, 26B Exhaust port 83C Cylindrical space 83D Pipe 83d Opening 85 Remote plasma source 85A Conduit 86A, 86B Valve 86a, 86b Gas line 100 Trap 145 Ultraviolet light source 145A Quartz window 201 Outer vessel 201A Cover plate 201D Opening 201a 201b Exhaust groove part 201d Quartz liner 202 Quartz reaction vessel 202A Quartz bottom plate 202B Quartz cover 203 Holding stand 203A Guard ring 204 Substrate transport part 204A Substrate transport port 204B Transport arm 205 Bearing part 205A Magnetic seal 205B Rotating shaft 206 Bellows 207A, 207B Conductance valve 207a, 207b Conduit 251 Valve body 251A Cap 251X Rotating shaft 252 Valve body 252A, 2 2B opening 252a intermediate portion 253 servomotor 254 temperature control mechanism 254A heater 255 outlet

Claims (26)

A processing container having a substrate holding table for holding a substrate to be processed;
A processing gas inlet formed on the first side of the substrate holder in the processing container;
A radical source formed on a second side of the processing container different from the first side with respect to the substrate holder;
A first exhaust port formed on the first side in the processing vessel;
A second exhaust port formed on the second side in the processing container;
A substrate processing apparatus comprising: an exhaust system coupled to the first exhaust port via a first variable conductance valve and coupled to the second exhaust port via a second variable conductance valve.   The substrate processing apparatus according to claim 1, wherein the radical source is de-energized while a processing gas is being introduced from the processing gas inlet.   3. The substrate processing apparatus according to claim 1, wherein the supply of the oxidation processing gas to the radical source is interrupted while the processing gas is being introduced from the processing gas introduction port.   While the processing gas is being introduced from the processing gas introduction port, the first variable conductance valve is closed, the second variable conductance valve is set to a predetermined opening, and the oxidation treatment is performed on the radical source. 4. While gas is supplied, the first variable valve conductance valve is set to a predetermined opening and the second variable conductance valve is closed. The substrate processing apparatus according to claim 1.   The substrate processing apparatus according to claim 1, wherein the radical source is a remote radical source.   The substrate processing apparatus according to claim 1, further comprising a rotation mechanism that rotates the substrate to be processed.   The substrate processing apparatus according to claim 1, wherein the radical source is further coupled to the exhaust system via a third variable conductance valve.   The radical source is coupled to the substrate processing apparatus and the exhaust system by a branch pipe having a first branch and a second branch, and the first branch includes the second variable conductance valve. 8. The substrate processing apparatus according to claim 7, wherein the radical supply source is coupled to the exhaust system, and the second branch is coupled to the exhaust system via the third variable conductance valve.   9. The substrate processing apparatus according to claim 7, wherein the first and second variable conductance valves are opened simultaneously when purging the inside of the processing container.   The substrate processing apparatus according to claim 7, wherein the first, second, and third variable conductance valves are simultaneously opened when purging the inside of the processing container. .   The substrate processing apparatus according to claim 7, wherein the first and second variable conductance valves have substantially the same configuration.   The substrate processing apparatus according to claim 7, wherein the radical source is a remote radical source that is supplied with oxygen gas and forms oxygen radicals.   The substrate processing apparatus according to claim 7, wherein the radical source is a remote radical source that is supplied with nitrogen gas and forms nitrogen radicals.   The substrate processing apparatus according to claim 7, further comprising a rotation mechanism that rotates the substrate to be processed.   The process container has a flat shape, and the process gas inlet forms a flat sheet-like process gas flow in the process container. The substrate processing apparatus according to the item.   The substrate processing apparatus according to claim 15, wherein the processing container defines a process space having a height of 0.5 to 8 mm on the substrate to be processed.   The substrate processing apparatus according to claim 15, wherein the processing container defines a process space having a height of 0.5 to 3.5 mm on the substrate to be processed.   The substrate processing apparatus according to claim 7, wherein the processing gas flow forms a laminar flow in the processing container. A substrate holding table for holding a substrate to be processed, and a processing container exhausted at an exhaust port;
A first raw material supply nozzle that is formed on the first side of the substrate holder in the processing container and introduces a first processing gas into the processing container in the form of a first laminar flow;
A second raw material supply nozzle that is formed on the second side of the substrate holder in the processing container and introduces a second processing gas into the processing container in the form of a second laminar flow;
A slit-shaped first exhaust port formed on the second side in the processing vessel and exhausting the first laminar flow;
A slit-shaped second exhaust port formed on the first side in the processing vessel and exhausting the second laminar flow;
A first exhaust pipe coupled to the first exhaust port; a second exhaust pipe coupled to the second exhaust port and provided with a conductance variable valve;
A substrate processing apparatus comprising: a cleaning gas supply source coupled to the second exhaust pipe between the second exhaust port and the conductance variable valve.   20. The substrate processing apparatus according to claim 19, wherein the cleaning gas supply source is a remote radical source that forms radicals of the cleaning gas. (A) purging the inside of the processing container;
(B) A processing gas is introduced into the processing container from a first side of the substrate to be processed, and processing gas molecules are adsorbed on the surface of the substrate to be processed, and then the first gas is applied to the substrate to be processed. Exhausting from a second side opposite the side;
(C) purging the inside of the processing container after the step (B);
(D) After the step (C), radicals are introduced into the processing container from the first side of the substrate to be processed to oxidize the processing gas molecules adsorbed on the surface of the substrate to be processed. In the substrate processing method comprising the step of exhausting from the second side,
The radical is formed by a radical source;
In the steps (A) and (C), the radical is flowed from the radical source to an exhaust system, and is supplied into the processing container in the step (D).   The substrate processing method according to claim 21, wherein the radical source is continuously driven during the steps (A) to (D).   In the steps (A) and (C), the purge step includes a step of evacuating the processing container using a part of a path for supplying the radical from the radical source to the processing container. The substrate processing method according to claim 21 or 22. In the processing container, a processing gas is flowed from the first side to the second side opposite to the first side along the surface of the processing substrate held in the processing container, and the processing target substrate Adsorbing process gas molecules on the surface;
Purging the inside of the processing vessel;
In the processing container, flowing an oxidation processing gas from the first side to the second side along the surface of the substrate to be processed, and oxidizing the processing gas molecules adsorbed on the surface of the substrate to be processed; A substrate processing method comprising:
A substrate processing method comprising the step of activating the oxidizing gas in the processing vessel by an ultraviolet light excitation process on the first side of the substrate to be processed to form radicals. A substrate holding table for holding a substrate to be processed; a processing container evacuated at first and second exhaust ports formed on the first and second sides of the substrate holding table, respectively; A source gas supply system that alternately supplies the first and second source gases from the second side to the first side and from the first side to the second side, respectively. A method for cleaning a substrate processing apparatus comprising:
In a state where the processing container is exhausted at the first exhaust port, the cleaning gas is passed through the second exhaust port from the exhaust pipe coupled to the second exhaust port. A cleaning method comprising a step of introducing.   26. The cleaning method according to claim 25, wherein the cleaning gas contains radicals.

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