阅读说明：本技术 气相成长方法及气相成长装置 (Vapor phase growth method and vapor phase growth apparatus ) 是由 和田直之 南出由生 于 2020-02-07 设计创作，主要内容包括：使用第1机器人(121),将在装载锁定室(13)待机的载具(C)在未搭载处理前的晶圆(WF)的状态下投入反应室(111),在将反应室(111)维持成既定的洗涤温度的状态下供给洗涤用气体,使用第1机器人(121),通过将在反应室(111)中已结束洗涤的载具(C)搬运至装载锁定室(13)来以既定频率洗涤载具(C)及基座(112)。之后,将载具(C)从反应室(111)搬出,将反应气体供给至反应室,在基座(112)的表面形成多晶硅膜(112P)。(A carrier (C) waiting in a load lock chamber (13) is introduced into a reaction chamber (111) by using a 1 st robot (121) in a state that a Wafer (WF) before processing is not loaded, and a cleaning gas is supplied while the reaction chamber (111) is maintained at a predetermined cleaning temperature, and the carrier (C) and a susceptor (112) are cleaned at a predetermined frequency by transporting the carrier (C) cleaned in the reaction chamber (111) to the load lock chamber (13) by using the 1 st robot (121). Then, the carrier (C) is carried out from the reaction chamber (111), and a reaction gas is supplied into the reaction chamber, thereby forming a polysilicon film (112P) on the surface of the susceptor (112).)

1. A vapor phase growth method comprising an annular carrier for supporting the outer periphery of a wafer, and sequentially transferring a plurality of wafers before processing to at least a susceptor of a reaction chamber for forming a CVD film on the wafer by using a plurality of the annular carriers,

after removing deposits adhering to the carrier and the base at a predetermined frequency, a polysilicon film is formed on the surface of the base.

2. The vapor phase growth method according to claim 1,

a plurality of wafers before processing are sequentially transferred to the reaction chamber through a factory interface, a load lock chamber and a wafer transfer chamber by using the plurality of carriers,

and a plurality of processed wafers are sequentially transferred from the reaction chamber to the factory interface through the wafer transfer chamber and the load lock chamber,

the load lock chamber is connected to the factory interface through the 1 st door and connected to the wafer transfer chamber through the 2 nd door,

the wafer transfer chamber is connected to the reaction chamber through a gate valve,

a 1 st robot is provided in the wafer transfer chamber, the 1 st robot loads a wafer before processing, which is transferred to the load lock chamber, into the reaction chamber while being mounted on the carrier, and takes out a wafer after processing, which has been processed in the reaction chamber, from the reaction chamber while being mounted on the carrier, and transfers the wafer to the load lock chamber,

a 2 nd robot is provided in the factory interface, the 2 nd robot takes out a wafer before processing from a wafer storage container, mounts the wafer on a carrier standing by in the load lock chamber, and stores a processed wafer carried on the carrier and transported to the load lock chamber into the wafer storage container,

a rack for supporting the carrier is provided at the load lock chamber.

3. The vapor phase growth method according to claim 2,

in the reaction chamber, after removing deposits adhering to the carrier and the susceptor, a polysilicon film is formed on the surface of the susceptor.

4. The vapor phase growth method according to claim 2 or 3,

in order to form a polysilicon film on the surface of the base after removing deposits adhering to the carrier and the base,

the first robot 1 is used to load a carrier waiting in the load lock chamber into the reaction chamber and mount the carrier on the susceptor without mounting a wafer before processing,

supplying a cleaning gas while maintaining the reaction chamber at a predetermined cleaning temperature,

the 1 st robot is used to transport the carrier whose washing has been completed in the reaction chamber to the load lock chamber,

supplying a reaction gas to the reaction chamber to form a polysilicon film on the surface of the susceptor.

5. A vapor phase growth apparatus comprising an annular carrier for supporting the outer edge of a wafer, and a plurality of wafers before processing are sequentially transferred to a susceptor in a reaction chamber for forming a CVD film on at least the wafer by using a plurality of the carriers,

a polysilicon film is formed on the surface of the base, and a polysilicon film is not formed on the surface of the carrier.

6. A vapor growth apparatus according to claim 5,

using the carriers, a plurality of wafers before processing are sequentially transferred to the reaction chamber through a factory interface, a load lock chamber and a wafer transfer chamber,

and sequentially transferring a plurality of processed wafers from the reaction chamber to the factory interface via the wafer transfer chamber and the load lock chamber,

the load lock chamber is connected to the factory interface through the 1 st door and connected to the wafer transfer chamber through the 2 nd door,

the wafer transfer chamber is connected to the reaction chamber through a gate valve,

a 1 st robot is provided in the wafer transfer chamber, the 1 st robot loads a wafer before processing, which is transferred to the load lock chamber, into the reaction chamber while being mounted on the carrier, and takes out a wafer after processing, which has been processed in the reaction chamber, from the reaction chamber while being mounted on the carrier, and transfers the wafer to the load lock chamber,

a 2 nd robot is provided in the factory interface, the 2 nd robot takes out a wafer before processing from a wafer storage container, mounts the wafer on a carrier standing by in the load lock chamber, and stores a processed wafer carried on the carrier and transported to the load lock chamber into the wafer storage container,

a rack for supporting the carrier is provided at the load lock chamber.

7. A vapor growth apparatus according to claim 6,

a 1 st robot for placing a carrier standing by in the load lock chamber into the reaction chamber without mounting a wafer before processing and mounting the carrier on the susceptor,

supplying a cleaning gas while maintaining the reaction chamber at a predetermined cleaning temperature,

after the carrier whose cleaning has been completed in the reaction chamber is transferred to the load lock chamber by the 1 st robot, a reaction gas is supplied to the reaction chamber, and a polysilicon film is formed on the surface of the susceptor.

Technical Field

The present invention relates to a vapor phase growth method and a vapor phase growth apparatus for manufacturing an epitaxial wafer and the like.

Background

In a vapor phase growth apparatus used for manufacturing an epitaxial wafer or the like, in order to minimize damage to the back surface of a silicon wafer, it is proposed that the silicon wafer be transported in a process from a load lock chamber to a reaction chamber in a state where the silicon wafer is mounted on a ring-shaped carrier (patent document 1).

Patent document 1 U.S. patent application publication No. 2017/0110352.

When the production of a silicon epitaxial wafer or the like is repeated by using such a vapor phase growth apparatus, polycrystalline silicon and its decomposition products are gradually deposited not only on the inner wall of the reaction chamber but also on the surface of the carrier. Then, the deposit peels off from the inner wall of the reaction chamber and the surface of the carrier to become particles, and the deposit floats in the reaction chamber and the transfer chamber due to the hot air in the reaction chamber, and the portion adheres to the surface of the wafer, thereby causing a problem of deterioration in quality such as electrical characteristics of the product wafer. On the other hand, since the susceptor tends to contain many metal impurities and is likely to be a source of contamination, it is necessary to suppress metal contamination by the susceptor by covering the surface of the susceptor with a polysilicon film. Therefore, it is desired to develop a vapor phase growth apparatus and a vapor phase growth method capable of suppressing defects such as contamination by particles, deposition on the back surface of a wafer, and adhesion scratch (sticking) to the wafer.

Disclosure of Invention

The present invention has been made to solve the problem of providing a vapor phase growth method and a vapor phase growth apparatus capable of suppressing contamination caused by particles, deposition on the back surface of a wafer, and adhesion scratches with the wafer.

The present invention is a vapor phase growth method including a ring-shaped carrier for supporting an outer edge (including an end portion or an outer peripheral portion, which will be the same as in the present specification) of a wafer, and sequentially transporting a plurality of wafers before processing to a susceptor of a reaction chamber for forming a CVD film at least on the wafer by using a plurality of the carriers, wherein a polysilicon film is formed on a surface of the susceptor after removing deposits adhering to the carrier and the susceptor at a predetermined frequency.

In the present invention, it is more preferable that a plurality of wafers before processing are sequentially transferred from the reaction chamber to the reaction chamber via a factory interface, a load lock chamber and a wafer transfer chamber by using the plurality of carriers, and a plurality of wafers after processing are sequentially transferred from the reaction chamber to the factory interface via the wafer transfer chamber and the load lock chamber, the load lock chamber communicates with the factory interface via a 1 st door and communicates with the wafer transfer chamber via a 2 nd door, the wafer transfer chamber communicates with the reaction chamber via a gate valve, a 1 st robot is provided in the wafer transfer chamber, the 1 st robot puts the wafers before processing transferred to the load lock chamber into the reaction chamber in a state of being mounted on the carrier, and takes out the wafers after processing finished in the reaction chamber from the reaction chamber in a state of being mounted on the carrier, and a 2 nd robot that takes out a wafer before processing from a wafer storage container and mounts the wafer on a carrier standing by in the load lock chamber, and that stores a processed wafer loaded on the carrier into the wafer storage container, wherein the wafer is transported to the load lock chamber, and a rack that supports the carrier is provided in the load lock chamber.

In the present invention, it is more preferable that after removing deposits adhering to the carrier and the susceptor in the reaction chamber, a polysilicon film is formed on the surface of the susceptor.

In the present invention, it is more preferable that, in order to form a polysilicon film on the surface of the susceptor after removing deposits adhering to the carrier and the susceptor, the carrier standing by in the loadlock chamber is loaded into the reaction chamber and mounted on the susceptor without mounting a wafer before processing by the 1 st robot, a cleaning gas is supplied while maintaining the reaction chamber at a predetermined cleaning temperature, and after the carrier whose cleaning has been completed in the reaction chamber is transferred to the loadlock chamber by the 1 st robot, a reaction gas is supplied to the reaction chamber to form a polysilicon film on the surface of the susceptor.

The present invention is a vapor phase growth apparatus including a ring-shaped carrier for supporting an outer edge of a wafer, and a plurality of wafers before processing are sequentially transferred to a susceptor of a reaction chamber for forming a CVD film at least on the wafer by using a plurality of the carriers, wherein a polysilicon film is formed on a surface of the susceptor, and a polysilicon film is not formed on a surface of the carrier.

In the present invention, it is more preferable that a plurality of wafers before processing are sequentially transferred from the reaction chamber to the reaction chamber through a factory interface, a load lock chamber and a wafer transfer chamber by using the plurality of carriers, and a plurality of wafers after processing are sequentially transferred from the reaction chamber to the factory interface through the wafer transfer chamber and the load lock chamber, the load lock chamber communicates with the factory interface through a 1 st door and communicates with the wafer transfer chamber through a 2 nd door, the wafer transfer chamber communicates with the reaction chamber through a gate valve, a 1 st robot is provided in the wafer transfer chamber, the 1 st robot transfers the wafers before processing transferred to the load lock chamber into the reaction chamber in a state of being mounted on the carriers, and takes out the wafers after processing having finished in the reaction chamber from the reaction chamber in a state of being mounted on the carriers, and a 2 nd robot that takes out a wafer before processing from a wafer storage container and mounts the wafer on a carrier standing by in the load lock chamber, and that stores a processed wafer loaded on the carrier into the wafer storage container, wherein the wafer is transported to the load lock chamber, and a rack that supports the carrier is provided in the load lock chamber.

In the present invention, it is more preferable that the carrier waiting in the loadlock chamber is loaded into the reaction chamber by the 1 st robot in a state where a wafer before processing is not mounted thereon, the carrier is mounted on the susceptor, a cleaning gas is supplied while the reaction chamber is maintained at a predetermined cleaning temperature, the carrier whose cleaning has been completed in the reaction chamber is transferred to the loadlock chamber by the 1 st robot, and then a reaction gas is supplied to the reaction chamber, thereby forming a polysilicon film on the surface of the susceptor.

Effects of the invention

According to the present invention, the polysilicon film is formed on the susceptor, so that contamination of the wafer by particles is suppressed. In addition, the polysilicon film is not formed on the carrier, so that the deposition on the back surface of the wafer and the adhesion scratch with the wafer can be inhibited.

Drawings

FIG. 1 is a block diagram showing a vapor phase growth apparatus according to an embodiment of the present invention.

Fig. 2A is a plan view of a carrier according to an embodiment of the present invention.

Fig. 2B is a cross-sectional view of a carrier including a wafer and a susceptor of a reaction furnace.

Fig. 2C is an enlarged cross-sectional view of a carrier including a wafer and a susceptor of a reaction furnace.

Fig. 3A is a plan view showing a rack provided in the load lock chamber.

Fig. 3B is a cross-sectional view of a rack including a wafer and a carrier.

Fig. 4 is a plan view and a sectional view showing a transfer flow of the wafer and the carrier in the load lock chamber.

Fig. 5 is a plan view and a sectional view showing a transfer flow of the wafer and the carrier in the reaction chamber.

Fig. 6(a) is a plan view showing an example of the 1 st blade attached to the end of the hand of the 1 st robot, and fig. 6(B) is a cross-sectional view of the 1 st blade including the carrier and the wafer.

Fig. 7 is a diagram (1) showing a flow of handling a wafer and a carrier in the vapor phase growth apparatus according to the present embodiment.

Fig. 8 is a diagram (2) showing a flow of handling the wafer and the carrier in the vapor phase growth apparatus according to the present embodiment.

Fig. 9 is a diagram (3) showing a flow of handling wafers and carriers in the vapor phase growth apparatus according to the present embodiment.

Fig. 10 is a diagram (4) showing a flow of handling the wafer and the carrier in the vapor phase growth apparatus according to the present embodiment.

Fig. 11 is a diagram (seed 1) showing a carrier washing/seeding process of the vapor phase growth apparatus according to the present embodiment.

Fig. 12 is a diagram (seed 2) showing a carrier washing/seeding process of the vapor phase growth apparatus according to the present embodiment.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a block diagram showing a vapor phase growth apparatus 1 according to an embodiment of the present invention, and a main body of the vapor phase growth apparatus 1 shown at the center is shown in a plan view. The vapor phase growth apparatus 1 of the present embodiment is a so-called CVD apparatus, and includes a pair of reaction furnaces 11 and 11, a wafer transfer chamber 12 in which a 1 st robot 121 for processing a wafer WF such as a single crystal silicon wafer is disposed, a pair of load lock chambers 13, a factory interface 14 in which a 2 nd robot 141 for processing the wafer WF is disposed, and a load port in which a wafer storage container 15 (cassette) for storing a plurality of wafers WF is disposed.

The factory interface 14 is an area similar to the clean room atmosphere on which the wafer container 15 is placed. The factory interface 14 is provided with a 2 nd robot 141, and the 2 nd robot 141 takes out the wafers WF before processing stored in the wafer storage container 15 and loads them into the load lock chamber 13, while storing the wafers WF after processing transported to the load lock chamber 13 into the wafer storage container 15. The 2 nd robot 141 is controlled by the 2 nd robot controller 142, and the 2 nd blade 143 attached to the tip of the robot hand moves along a predetermined trajectory learned in advance.

An airtight openable and closable 1 st door 131 is provided between the load lock chamber 13 and the factory interface 14, and an airtight openable and closable 2 nd door 132 is similarly provided between the load lock chamber 13 and the wafer transfer chamber 12. The load lock chamber 13 functions as a space for replacing an atmosphere gas between the wafer transfer chamber 12 in an inert gas atmosphere and the factory interface 14 in an atmospheric atmosphere. Therefore, an exhaust device for vacuum-exhausting the inside of the load lock chamber 13 and a supply device for supplying an inert gas to the load lock chamber 13 are provided.

For example, when the wafer WF before processing is transferred from the wafer storage container 15 to the wafer transfer chamber 12, the 1 st door 131 on the factory interface 14 side is closed, the 2 nd door 132 on the wafer transfer chamber 12 side is closed, the wafer WF in the wafer storage container 15 is taken out by the 2 nd robot 141 in a state where the load lock chamber 13 is made to be an inert gas atmosphere, the 1 st door 131 on the factory interface 14 side is opened, and the wafer WF is transferred to the load lock chamber 13. Next, after the 1 st door 131 on the factory interface 14 side is closed and the load lock chamber 13 is again made to be an inert gas atmosphere, the 2 nd door 132 on the wafer transfer chamber 12 side is opened, and the wafer WF is transferred to the wafer transfer chamber 12 by the 1 st robot 121.

On the other hand, when the processed wafer WF is transferred from the wafer transfer chamber 12 to the wafer storage container 15, the 1 st door 131 on the factory interface 14 side is closed, the 2 nd door 132 on the wafer transfer chamber 12 side is opened in a state where the load lock chamber 13 is made to be an inert gas atmosphere, and the wafer WF in the wafer transfer chamber 12 is transferred to the load lock chamber 13 by the 1 st robot 121. Next, after the 2 nd door 132 on the wafer transfer chamber 12 side is closed and the load lock chamber 13 is again made to be an inert gas atmosphere, the 1 st door 131 on the factory interface 14 side is opened and the wafer WF is transferred to the wafer storage container 15 by the 2 nd robot 141.

The wafer transfer chamber 12 is a closed chamber, one of which is connected to the load lock chamber 13 via an airtight 2 nd door 132 that can be opened and closed, and the other of which is connected via an airtight gate valve 114 that can be opened and closed. The wafer transfer chamber 12 is provided with a 1 st robot 121, and the 1 st robot 121 transfers the wafer WF before processing from the load lock chamber 13 to the reaction chamber 111 and transfers the wafer WF after processing from the reaction chamber 111 to the load lock chamber 13. The 1 st robot 121 is controlled by the 1 st robot controller 122, and the 1 st blade 123 attached to the tip of the robot hand moves along a previously learned motion trajectory.

The manifold controller 16, the 1 st robot controller 122, and the 2 nd robot controller 142, which control the entire manifold vapor phase growth apparatus 1, receive and transmit control signals from each other. When the operation command signal from the bus controller 16 is transmitted to the 1 st robot controller 122, the 1 st robot controller 122 controls the operation of the 1 st robot 121, and the operation result of the 1 st robot 121 is transmitted from the 1 st robot controller 122 to the bus controller 16. Thereby, the manifold controller 16 recognizes the operation state of the 1 st robot 121. Similarly, when the motion command signal from the bus controller 16 is transmitted to the 2 nd robot controller 142, the 2 nd robot controller 142 controls the motion of the 2 nd robot 141, and the motion result of the 2 nd robot 141 is transmitted from the 2 nd robot controller 142 to the bus controller 16. Thereby, the bus controller 16 recognizes the operation state of the 2 nd robot 141.

The inactive gas is supplied from an inactive gas supply device (not shown) to the wafer transfer chamber 12, and the gas in the wafer transfer chamber 12 is purged by a scrubber (scrubbing dust collector) connected to an exhaust port and then discharged to the outside of the system. Such a scrubber is not shown in detail, and a conventionally known pressurized water type scrubber can be used, for example.

The reaction furnace 11 is an apparatus for forming an epitaxial film on the surface of the wafer WF by CVD, and includes a reaction chamber 111, a susceptor 112 for placing and rotating the wafer WF is provided in the reaction chamber 111, and a source gas for supplying hydrogen gas and forming a CVD film (for example, silicon tetrachloride SiCl in the case where the CVD film is a silicon epitaxial film) is provided in the reaction chamber 111₄Trichlorosilane SiHCl₃Etc.), a dopant gas supply device 113. Although not shown, a heating lamp for raising the temperature of the wafer WF to a predetermined temperature is provided around the reaction chamber 111. Further, a gate valve 114 is provided between the reaction chamber 111 and the wafer transfer chamber 12, and the gate valve 114 is closed, whereby airtightness between the reaction chamber 111 and the wafer transfer chamber 12 is ensured. The driving of the susceptor 112 of the reaction furnace 11, the supply of gas by the gas supply device 113, the seeding, the opening/closing of the heating lamp, and the control of the opening/closing operation of the gate valve 114 are controlled by command signals from the master controller 16. Further, a vapor phase growth apparatus 1 shown in FIG. 1 is shownThe example in which a pair of reactors 11, 11 are provided, however, one reactor 11 may be provided, or three or more reactors may be provided.

The reactor 11 is also provided with a scrubber (scrubbing dust collector) having the same structure as the wafer transfer chamber 12. That is, the hydrogen gas, the raw material gas, and the dopant gas supplied from the gas supply device 113 are purged by a scrubber connected to an exhaust port provided in the reaction chamber 111, and then discharged to the outside of the system. As the scrubber, for example, a conventionally known pressurized water type scrubber can be used.

In the vapor phase growth apparatus 1 of the present embodiment, the wafer WF is transported between the load lock chamber 13 and the reaction chamber 111 by the annular carrier C supporting the entire outer peripheral edge of the wafer WF. Fig. 2A is a plan view showing a carrier C, fig. 2B is a sectional view of the carrier C including a wafer WF and a base 112 of the reaction furnace 11, fig. 2C is an enlarged sectional view of fig. 2B, and fig. 5 is a plan view and a sectional view showing a transfer flow of the wafer WF and the carrier C in the reaction chamber 111.

The carrier C of the present embodiment is formed of a material such as SiC, and is formed in a ring shape, and has a bottom surface C11 placed on the upper surface of the susceptor 112 shown in fig. 2B, an upper surface C12 contacting and supporting the entire outer periphery of the back surface of the wafer WF, an outer peripheral side wall surface C13, and an inner peripheral side wall surface C14. The carrier C of the present embodiment does not have a polysilicon film formed on its surface. Even if the production of the epitaxial wafer is repeated by using the source gas, the polycrystalline silicon film is formed on the surface of the carrier C and is removed by the cleaning process performed between the production process and the subsequent production process. When the wafer WF supported by the carrier C is carried into the reaction chamber 111, as shown in the plan view of fig. 5(a), the wafer WF is carried to the upper portion of the base 112 as shown in fig. B in a state where the carrier C is placed on the 1 st blade 123 of the 1 st robot 121, the carrier C is temporarily lifted up by three or more carrier lift pins 115 provided to be vertically movable with respect to the base 112 as shown in fig. C, the 1 st blade 123 is retreated as shown in fig. D, and the base 112 is raised as shown in fig. E, thereby placing the carrier C on the upper surface of the base 112. As shown in fig. 2C, a polysilicon film 112P is formed on the surface of the base 112 in the present embodiment. The polysilicon film 112P is formed by a series of processes after the washing process. Details will be described later.

On the contrary, when the wafer WF whose processing has been completed in the reaction chamber 111 is taken out in a state of being mounted on the carrier C, the base 112 is lowered as shown in fig. D from the state shown in fig. 5E, the carrier C is supported only by the carrier lift pins 115, the 1 st blade 123 is advanced between the carrier C and the base 112 as shown in fig. C, then the three carrier lift pins 115 are lowered as shown in fig. B, the 1 st blade 123 is mounted on the carrier C, and the hand of the 1 st robot 121 is operated. This enables the wafer WF after the completion of the processing to be taken out in a state of being mounted on the carrier C.

In the vapor phase growth apparatus 1 of the present embodiment, in order to transfer the carrier C between the steps from the load lock chamber 13 to the reaction chamber 111, the wafer WF before processing is placed on the carrier C in the load lock chamber 13, and the wafer WF after processing is taken out from the carrier C. Therefore, the load lock chamber 13 is provided with a rack 17 for supporting the carriers C on the upper and lower 2 levels. Fig. 3A is a plan view showing the rack 17 provided in the load lock chamber 13, and fig. 3B is a sectional view of the rack 17 including the wafer WF. The rack 17 of the present embodiment is provided with a fixed rack base 171, a 1 st rack 172 and a 2 nd rack 173 vertically and vertically provided on the rack base 171 and supporting two carriers C in two stages, and three wafer lift pins 174 vertically and vertically provided on the rack base 171.

The 1 st shelf 172 and the 2 nd shelf 173 (in the plan view of fig. 3A, the 2 nd shelf 173 is hidden by the 1 st shelf 172, and only the 1 st shelf 172 is shown) have protrusions for supporting the carriers C at 4 points, and one carrier C is placed on the 1 st shelf 172 and one carrier C is also placed on the 2 nd shelf 173. Further, the carrier C placed on the 2 nd rack 173 is inserted into the gap between the 1 st rack 172 and the 2 nd rack 173.

Fig. 4 is a plan view and a sectional view showing a transfer flow of the wafer WF and the carrier C in the load lock chamber 13, and also shows a flow of mounting the wafer WF before processing on the carrier C in a state where the carrier C is supported by the 1 st shelf 172 as shown in fig. (B). That is, the 2 nd robot 141 provided in the factory interface 14 places one wafer WF stored in the wafer storage container 15 on the 2 nd blade 143, and conveys the wafer WF to the upper portion of the rack 17 through the 1 st door 131 of the load lock chamber 13 as shown in fig. B. Next, as shown in fig. C, the three wafer lift pins 174 are raised with respect to the frame base 171, the wafer WF is temporarily lifted, and the 2 nd blade 143 is retreated as shown in fig. D. As shown in the plan view of fig. (a), the three wafer lift pins 174 are provided at positions not interfering with the 2 nd blade 143. Next, as shown in fig. D and E, the wafer WF is mounted on the carrier C by lowering the three wafer lift pins 174 and raising the 1 st shelf 172 and the 2 nd shelf 173.

On the other hand, when the processed wafer WF carried to the load lock chamber 13 in the state of being placed on the carrier C is carried to the wafer storage container 15, the three wafer lift pins 174 are raised and the 1 st and 2 nd racks 172 and 173 are lowered as shown in fig. D from the state shown in fig. 4E, the wafer WF is supported only by the wafer lift pins 174, the 2 nd blade 143 is advanced between the carrier C and the wafer WF as shown in fig. C, and then the three wafer lift pins 174 are lowered as shown in fig. B, the wafer WF is placed on the 2 nd blade 143, and the 2 nd robot 141 is operated manually. This enables the wafer WF having finished processing to be taken out from the carrier C to the wafer storage container 15. The wafer WF that has finished being processed in the state shown in fig. 4(E) is carried to the 1 st shelf 172 in the mounted state on the carrier C, but the wafer WF can be taken out from the carrier C to the wafer storage container 15 by the same flow in the case of being carried to the 2 nd shelf 173.

Fig. 6(a) is a plan view showing an example of the 1 st blade 123 attached to the tip of the hand of the 1 st robot 121, and fig. 6(B) is a cross-sectional view of the 1 st blade 123 including the carrier C and the wafer WF. The 1 st vane 123 of the present embodiment has a 1 st recess 124 formed in one surface of a short-side plate-like body, the diameter of which corresponds to the outer peripheral side wall surface C13 of the carrier C. The diameter of the 1 st recess 124 is formed slightly larger than the diameter of the outer peripheral side wall surface C13 of the carrier C. When the 1 st robot 121 carries the carrier C with the wafer WF or empty, the carrier C is placed in the 1 st recess 124.

Next, a flow of handling the wafer WF and the carrier C before the epitaxial film is grown (hereinafter, also referred to as just before the process) and after the epitaxial film is grown (hereinafter, also referred to as just after the process) in the vapor phase growth apparatus 1 according to the present embodiment will be described. Fig. 7 to 10 are schematic views showing a flow of handling of wafers and carriers C in the vapor phase growth apparatus according to the present embodiment, and a plurality of wafers W1, W2, and W3 … (for example, 25 wafers in total) are stored in the wafer storage container 15 corresponding to the wafer storage container 15, the load lock chamber 13, and the reaction furnace 11 on one side of fig. 1, and processing is started in this order.

Step S0 in fig. 7 shows a waiting state in which the process is started by the vapor phase growth apparatus 1, and a plurality of wafers W1, W2, and W3 … (for example, 25 wafers in total) are stored in the wafer storage container 15, and the empty carrier C1 is supported by the 1 st shelf 172 and the empty carrier C2 is supported by the 2 nd shelf 173, and the load lock chamber 13 is in an inert gas atmosphere.

In the next step S1, the 2 nd robot 141 places the wafer W1 stored in the wafer storage container 15 on the 2 nd blade 143, and opens the 1 st door 131 of the load lock chamber 13 to transfer the wafer to the carrier C1 supported by the 1 st shelf 172. The transfer flow is described with reference to fig. 4.

In the next step S2, the inside of the load-lock chamber 13 is replaced with the inert gas atmosphere again in a state where the 1 st door 131 closing the load-lock chamber 13 also closes the 2 nd door 132. Then, the 2 nd gate 132 is opened, the carrier C1 is mounted on the 1 st blade 123 of the 1 st robot 121, the gate valve 114 of the reaction furnace 11 is opened, and the carrier C1 on which the wafer W1 is mounted is transferred to the susceptor 112 through the gate valve 114. The transfer flow is described with reference to fig. 4. In steps S2 to S4, a CVD film is formed on the wafer W1 in the reaction furnace 11.

That is, the carrier C1 carrying the wafer W1 before processing is transferred to the susceptor 112 of the reaction chamber 111, the gate valve 114 is closed, and after a predetermined time of waiting, hydrogen gas is supplied to the reaction chamber 111 through the gas supply device 113, thereby making the reaction chamber 111 a hydrogen atmosphere. Next, the temperature of the wafer W1 in the reaction chamber 111 is raised to a predetermined temperature by a heating lamp, and after pretreatment such as etching and heat treatment is performed as necessary, the source gas and the dopant gas are supplied by the gas supply device 113 while controlling the flow rate and/or the supply time. Thereby, a CVD film is formed on the surface of the wafer W1. After the CVD film is formed, hydrogen gas is supplied again to the reaction chamber 111 by the gas supply device 113 to replace the reaction chamber 111 with a hydrogen gas atmosphere, and then the reaction chamber is kept stand by for a predetermined time.

While the wafer W1 is processed in the reaction furnace 11 in steps S2 to S4, the 2 nd robot 141 takes out the next wafer W2 from the wafer container 15 and prepares for the next process. Before that, in the present embodiment, in step S3, the inside of the load-lock chamber 13 is replaced with the inert gas atmosphere in a state where the 2 nd door 132 closing the load-lock chamber 13 also closes the 1 st door 131. Then, the 2 nd door 132 is opened, the carrier C2 supported on the 2 nd rack 173 is transferred to the 1 st rack 172 by the 1 st robot 121, and the 2 nd door 132 is closed. Next, in step S4, the 2 nd robot 141 places the wafer W2 stored in the wafer storage container 15 on the 2 nd blade 143, opens the 1 st door 131, and transfers the wafer W to the carrier C2 supported by the 1 st shelf 172 of the load lock chamber 13.

In this way, in the present embodiment, the step S3 is added, and the unprocessed wafer WF stored in the wafer storage container 15 is mounted on the 1 st rack 172 which is the uppermost rack of the racks 17 in the load lock chamber 13. This is because of the following reason. That is, as shown in step S2, when the empty carrier C2 on which the next wafer W2 is mounted is supported by the 2 nd rack 173, there is a possibility that the carrier C1 on which the processed wafer W1 is mounted is transferred to the 1 st rack 172 when the wafer W2 is mounted thereon. Since the carriers C of the vapor phase growth apparatus 1 of the present embodiment are conveyed to the reaction chamber 111, the carriers C become a cause of generation of particles, and when the carriers C1 are supported on the upper portion of the wafers W2 before processing, dust may fall onto the wafers W2 before processing. Therefore, step S3 is added to transfer the empty carrier C2 to the 1 st rack 172 so that the wafer WF before processing is mounted on the uppermost rack (the 1 st rack 172) of the racks 17 in the load lock chamber 13.

In step S5, the inside of the load-lock chamber 13 is replaced with an inert gas atmosphere in a state where the 1 st door 131 closing the load-lock chamber 13 also closes the 2 nd door 132. Then, the gate valve 114 of the reaction furnace 11 is opened, the 1 st blade 123 of the 1 st robot 121 is inserted into the reaction chamber 111, the carrier C1 on which the processed wafer W1 is mounted is transferred, the wafer W is taken out from the reaction chamber 111, the gate valve 114 is closed, the 2 nd gate 132 is opened, and the wafer W is transferred to the 2 nd rack 173 of the load lock chamber 13. Next, the carrier C2 supported by the 1 st shelf 172 is placed on the 1 st blade 123 of the 1 st robot 121, and the carrier C2 on which the wafer W2 before processing is mounted is transferred to the susceptor 112 of the reaction furnace 11 through the wafer transfer chamber 12 and the gate valve 114 is opened as shown in step S6.

In steps S6 to S9, a CVD film is formed on the wafer W2 in the reaction furnace 11. That is, the carrier C2 on which the wafer W2 before processing is mounted is transferred to the susceptor 112 of the reaction chamber 111, the gate valve 114 is closed, and after a predetermined time of waiting, hydrogen gas is supplied to the reaction chamber 111 by the gas supply device 113 to make the reaction chamber 111 a hydrogen atmosphere. Next, the temperature of the wafer W2 in the reaction chamber 111 is raised to a predetermined temperature by a heating lamp, and after pretreatment such as etching and heat treatment is performed as necessary, the source gas and the dopant gas are supplied by the gas supply device 113 while controlling the flow rate and/or the supply time. Thereby, a CVD film is formed on the surface of the wafer W2. After the CVD film is formed, hydrogen gas is supplied again to the reaction chamber 111 by the gas supply device 113, and the reaction chamber 111 is replaced with a hydrogen gas atmosphere and then stands by for a predetermined time.

While the wafer W2 is processed in the reaction furnace 11 in steps S6 to S9, the 2 nd robot 141 stores the processed wafer W1 in the wafer container 15, and takes out the next wafer W3 from the wafer container 15 to prepare for the next process. That is, in step S7, the inside of the load-lock chamber 13 is replaced with the inert gas atmosphere in a state where the 2 nd door 132 that closes the load-lock chamber 13 also closes the 1 st door 131. Then, the 1 st door 131 is opened, and the processed wafer W1 is placed on the 2 nd blade 143 from the carrier C1 supported by the 2 nd rack 173 by the 2 nd robot 141, and the processed wafer W1 is stored in the wafer storage container 15 as shown in step S8. Next, in step S8, similarly to step S3 described above, the inside of the load-lock chamber 13 is replaced with an inert gas atmosphere in a state where the 1 st door 131 closing the load-lock chamber 13 also closes the 2 nd door 132. Then, the 2 nd door 132 is opened, and the carrier C1 supported on the 2 nd rack 173 is transferred to the 1 st rack 172 by the 1 st robot 121.

Next, in step S9, the inside of the load-lock chamber 13 is replaced with an inert gas atmosphere in a state where the 2 nd door 132 closing the load-lock chamber 13 also closes the 1 st door 131. Then, the 2 nd robot 141 places the wafer W3 stored in the wafer storage container 15 on the 2 nd blade 143, and opens the 1 st door 131 to transfer the wafer W to the carrier C1 supported by the 1 st shelf 172 of the load lock chamber 13 as shown in step S9.

In step S10, similarly to step S5 described above, the inside of the load-lock chamber 13 is replaced with an inert gas atmosphere in a state where the 1 st door 131 closing the load-lock chamber 13 also closes the 2 nd door 132. Then, the gate valve 114 of the reaction furnace 11 is opened, the 1 st blade 123 of the 1 st robot 121 is inserted into the reaction chamber 111, the carrier C2 on which the processed wafer W2 is mounted is placed, and after the gate valve 114 is closed, the 2 nd door 132 is opened, and the wafer is transferred from the reaction chamber 111 to the 2 nd rack 173 of the load lock chamber 13. Next, carrier C1 supported by the 1 st shelf 172 is placed on the 1 st blade 123 of the 1 st robot 121, and carrier C1 on which the wafer W3 before processing is mounted is transferred to the susceptor 112 of the reactor 11 through the wafer transfer chamber 12 as shown in step S11.

In step S10, similarly to step S7 described above, the inside of the load-lock chamber 13 is replaced with an inert gas atmosphere in a state where the 2 nd door 132 closing the load-lock chamber 13 also closes the 1 st door 131. Then, the 1 st door 131 is opened, and the processed wafer W2 is transferred from the carrier C2 supported by the 2 nd rack 173 to the 2 nd blade 143 by the 2 nd robot 141, and the processed wafer W2 is stored in the wafer storage container 15 as shown in step S11. Thereafter, the above steps are repeated until all the wafers WF stored in the wafer storage container 15 before being processed are processed.

As described above, in the vapor phase growth apparatus 1 of the present embodiment, while the processing is performed in the reaction furnace 11, the wafers WF before the next processing are taken out of the wafer storage container 15 and prepared, or the processed wafers WF are stored in the wafer storage container 15, so that the time taken for only carrying can be minimized. In this case, as shown in the rack 17 of the present embodiment, when the number of waiting times of the carriers C in the load lock chamber 13 is set to 2 or more, the degree of freedom of shortening only the time taken for transportation becomes further high. Considering the exclusive space of the load lock chamber 13, the exclusive space of the entire vapor phase growth apparatus 1 becomes smaller when the plurality of carriers C are arranged in a plurality of stages in the vertical direction than when the plurality of carriers C are arranged in the horizontal direction. However, when a plurality of carriers C are arranged in a plurality of stages in the vertical direction, the carriers C may be supported on the upper portion of the wafer WF before processing, and dust may fall onto the wafer WF before processing. However, in the vapor phase growth apparatus 1 of the present embodiment, steps S3 and S8 are added so that the wafer WF before processing is mounted on the uppermost rack (the 1 st rack 172) of the racks 17 of the load lock chamber 13, and the empty carrier C2 is transferred to the 1 st rack 172, whereby the wafer WF before processing is mounted on the uppermost carrier C. As a result, the adhesion of particles to the wafer WF by the carrier C can be suppressed, and the quality of the LPD can be improved.

Further, when the production of a plurality of silicon epitaxial wafers is repeated in the above-described flow, not only the inner wall of the cavity constituting the reaction chamber 111 and the susceptor 112 but also polycrystalline silicon caused by the reaction gas and decomposition products thereof are gradually deposited on the surface of the carrier C loaded into the reaction chamber 111 on which the wafer WF is mounted. In order to remove the deposit regularly, the reaction chamber 111 and the carrier C are washed at a predetermined frequency. It is desirable not to form a polysilicon film on the surface of the carrier C from the viewpoint of suppressing deposition on the back surface of the wafer due to mass transfer and preventing sticking scratches to the wafer. On the other hand, it is desirable to form a polysilicon film 112P on the surface of the susceptor 112 in order to suppress contamination of the wafer by particles (see fig. 2C). Fig. 11 and 12 are diagrams showing a washing/seeding/coating flow of the carrier C in the vapor phase growth apparatus 1 according to the present embodiment.

Step S20 in fig. 11 shows a standby state in which the vapor phase growth process such as epitaxial layer generation is completed and the cleaning process is started, in which the empty carrier C1 is supported by the 1 st rack 172 of the load lock chamber 13, the empty carrier C2 is supported by the 2 nd rack 173, and the load lock chamber 13 is in an inert gas atmosphere.

In the next step S21, the 2 nd door 132 of the load lock chamber 13 is opened, the empty carrier C1 is placed on the 1 st blade 123 of the 1 st robot 121, the gate valve 114 of the reaction furnace 11 is opened, and the carrier C1 is transferred to the susceptor 112 through the gate valve 114. The transfer flow is described with reference to fig. 4. In step S21, the reactor 11 is cleaned with respect to the carrier C1, the inner wall of the reaction chamber 111, the susceptor 112, and the like. The washing process of this example was performed by an etching process.

That is, the empty carrier C1 is transferred to the susceptor 112 of the reaction chamber 111, the gate valve 114 is closed, the reaction chamber 111 is heated to a predetermined cleaning temperature (for example, 1190 ℃) by the heater lamp, and the etching gas such as hydrogen chloride HCl is supplied at a predetermined flow rate for a predetermined time by the gas supply device 113. Thereby, the polysilicon and the decomposition products thereof deposited on the surface of the carrier C1, the inner wall of the reaction chamber 111, and the surface of the susceptor 112 are etched (ablated).

After the cleaning process by etching is completed, the gate valve 114 of the reaction furnace 11 is opened, the 1 st blade 123 of the 1 st robot 121 is inserted into the reaction chamber 111, the carrier C1 after the cleaning process is placed thereon and taken out from the reaction chamber 111, the gate valve 114 is closed, the 2 nd door 132 is opened, and the carrier C is transferred to the 1 st rack 172 of the load lock chamber 13 (step S22). Next, the empty carrier C2 supported on the 2 nd rack 173 is placed on the 1 st blade 123 of the 1 st robot 121, and as shown in step S23 in fig. 12, the gate valve 114 is opened, and the carrier C2 is transferred to the susceptor 112 of the reaction furnace 11 through the wafer transfer chamber 12.

In step S23, the reactor 11 is subjected to a cleaning process with respect to the carrier C2, the inner wall of the reaction chamber 111, the susceptor 112, and the like. That is, the empty carrier C2 is transferred to the susceptor 112 of the reaction chamber 111, the gate valve 114 is closed, the reaction chamber 111 is heated to a predetermined cleaning temperature (for example, 1190 ℃) by the heater lamp, and the etching gas such as hydrogen chloride HCl is supplied at a predetermined flow rate for a predetermined time by the gas supply device 113. Thereby, the polysilicon and the decomposition products thereof deposited on the surface of the carrier C2, the inner wall of the reaction chamber 111, and the surface of the susceptor 112 are etched (ablated).

After the washing process is completed, the gate valve 114 of the reaction furnace 11 is opened, the 1 st blade 123 of the 1 st robot 121 is inserted into the reaction chamber 111, the washed carrier C2 is placed thereon and taken out of the reaction chamber 111, the gate valve 114 is closed, and the 2 nd door 132 is opened and transferred to the 2 nd rack 173 of the load lock chamber 13 (step S24). Through the above steps S20 to S24, the cleaning process of the reactor 11 including the pair of carriers C1 and C2 is completed. This makes it possible to form carrier C without forming a polysilicon film on the surface.

In the next step S25, hydrogen gas is supplied to the reaction chamber 111 closed by the gate valve 114 via the gas supply device 113, and the reaction chamber 111 is made to be in a hydrogen gas atmosphere. Subsequently, the temperature of the reaction chamber 111 is raised to a predetermined temperature (for example, 1130 ℃ C.) by the heating lamp, and the raw material gas is supplied by the gas supply device 113 while controlling the flow rate and/or the supply time. Thereby, a polysilicon film 112P is grown on the surface of the susceptor 112. At the same time, a polysilicon film is also formed on the inner wall of the reaction chamber 111. After a polysilicon film is formed on the surface of the susceptor 112, hydrogen gas is supplied again to the reaction chamber 111 by the gas supply device 113 to replace the reaction chamber 111 with a hydrogen gas atmosphere. Thereby, the susceptor 112 having the polysilicon film 112P formed on the surface thereof is obtained.

Description of the reference numerals

1 … vapor phase growth apparatus

11 … reaction furnace

111 … reaction chamber

112 … base

112P … polysilicon film

113 … gas supply device

114 … gate valve

115 … Carrier Lift Pin

12 … wafer transfer chamber

121 … robot 1

122 … No. 1 robot controller

123 … No. 1 blade

124 … recess 1

13 … load lock chamber

131 … door 1

132 … door 2

14 … factory interface

141 … No. 2 robot

142 … No. 2 robot controller

143 … No. 2 blade

15 … wafer container

16 … all-purpose controller

17 … shelf

171 … shelf base

172 … item 1

173 nd 173 … nd shelf

174 … wafer lift pin

C … carrier

Bottom surface of C11 …

Upper surface of C12 …

C13 … outer peripheral side wall surface

C14 … inner peripheral side wall surface

WF … wafer.