JP2014060327A - Substrate processing apparatus, substrate processing method, and manufacturing method of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the temperature reduction time after the substrate processing and ease the damage of a component in a spare room which is caused by radiation heat.SOLUTION: A substrate processing apparatus includes: a substrate holder which holds multiple substrates; a processing chamber which houses the substrate holder and processes the substrates; a spare chamber which is disposed so as to communicate with the processing chamber through an opening in an airtight manner, houses the substrate holder, and transports the substrates; lifting means which moves up and down the substrate holder between the processing chamber and the spare chamber; a cooling wall which is disposed between the lifting means and the substrate holder in the spare chamber; and a cooling gas supply part which is provided at a position facing the cooling wall across the substrate holder, supplies a cooling gas to the substrate holder and the substrates, and then causes the cooling gas to collide with the cooling wall.

Description

  The present invention relates to a substrate processing apparatus, a substrate processing method, and a semiconductor device manufacturing method for growing an epitaxial silicon carbide film on a silicon carbide wafer.

  Silicon carbide (SiC) has attracted attention as an element material for power devices because it has a larger energy band cap and higher withstand voltage than silicon (Si). It is known that SiC has a higher melting point than Si, does not have a liquid phase under normal pressure, and has a small impurity diffusion coefficient, making it difficult to produce substrates and devices as compared to Si.

  For example, the SiC epitaxial film forming apparatus has an Si epitaxial film forming temperature of 900 to 1200 ° C., whereas that of SiC is as high as about 1500 to 1800 ° C. Need to be creative. In addition, since the film formation proceeds by the reaction of two elements of Si and C, it is necessary to devise a device that is neither in a film thickness or composition uniformity, nor in a doping level control technique nor a silicon film forming apparatus.

As a mass-produced SiC epitaxial growth apparatus, a single-wafer type apparatus called “pancake type” or “planetary type” is mainly used. In these apparatuses, films are formed by a method in which several to dozen or more SiC substrates are arranged in a plane on a susceptor heated to a film formation temperature by high frequency or the like, and a source gas or a carrier gas is supplied. C ₃ H ₈ (propane) or C ₂ H ₄ (ethylene) is often used as the C raw material, SiH ₄ (monosilane) is often used as the Si raw material, and H ₂ (hydrogen) is used as the carrier. Hydrogen chloride (HCl) is added for the purpose of suppressing silicon nucleation in the gas phase and improving the quality of crystals, or tetrachlorosilane (SiCl ₄ , silicon tetrachloride) containing chlorine (Cl) in the structure. Sometimes raw materials are used.

  However, these SiC epitaxial film forming apparatuses have the following problems. In the “pancake-type” and “planetary-type” reaction chamber structures, the silicon film forming material and the carbon film forming material are supplied to the planarly arranged wafer from the gas supply unit installed in the center and exhausted. Is generally performed from the periphery, and the concentration distribution of the gas greatly changes from the supply port to the exhaust port. In general, the film thickness non-uniformity associated with this is also avoided by rotating the wafer and the susceptor during film formation. In order to increase the number of substrates that can be processed at a time, the diameter of the susceptor may be increased. However, increasing the diameter of the susceptor increases the size of the apparatus and increases the cost. This problem becomes more serious as the wafer diameter increases. In addition, when two or more wafers are arranged from the gas supply direction to the gas exhaust port direction (radial direction), a difference in film thickness occurs between the wafers due to the above-mentioned gas concentration difference problem. There is a problem that is limited.

  On the other hand, a vertical substrate processing apparatus used for silicon film formation has a structure in which a plurality of wafers (for example, 25 to 100 wafers) are stacked in a vertical direction at a time with a footprint corresponding to one sheet and processed in a batch. Therefore, it is very advantageous for mass production. As an example of applying the technology of the vertical substrate processing apparatus to SiC epitaxial growth, Patent Document 1 is known.

  However, such a vertical substrate processing apparatus has a structure in which a SiC wafer is loaded on a boat to form a film, but since the film forming temperature is high as described above, it takes time to lower the temperature after processing, There is a problem of affecting the throughput of the apparatus. In addition, when the boat is lowered into the load lock chamber while the temperature of the SiC wafer is high, there is a problem that the components in the load lock chamber are damaged by the radiant heat.

JP 2008-227264 A

  Therefore, the present invention has been made to solve the above problems. An object of the present invention is to provide a substrate processing apparatus, a substrate processing method, and a semiconductor device manufacturing method capable of shortening a temperature lowering time after processing a substrate and alleviating damage to components in a spare chamber due to radiant heat.

  In order to achieve the above object, a substrate processing apparatus according to one aspect of the present invention includes a substrate holder that holds a plurality of substrates in a vertical direction, and a substrate that holds the substrate holder and holds a substrate with a predetermined processing gas and a predetermined A processing chamber for processing at a temperature of the substrate, a preliminary chamber that is disposed so as to be airtightly communicated with the processing chamber through the opening, accommodates the substrate holder, and transfers the substrate; and Lifting means that moves up and down between the processing chamber and the preliminary chamber, a cooling wall disposed between the lifting means and the substrate holder in the preliminary chamber, and a position facing the cooling wall across the substrate holder And a cooling gas supply section for supplying a cooling gas to the substrate holder and the substrate and then colliding with the cooling wall.

  A substrate processing method according to another aspect of the present invention includes a step of storing a substrate holder holding a plurality of substrates in a vertical direction in a processing chamber and processing the substrate at a predetermined processing gas and a predetermined temperature. After the step of processing the substrate, the step of unloading the substrate holder to the preliminary chamber arranged so as to be airtightly communicated with the processing chamber through the opening, and the holding of the substrate transferred to the preliminary chamber A step of supplying a cooling gas from a position facing the cooling wall to cool the substrate holder and the substrate and causing the cooling gas to collide with the cooling wall with respect to the cooling wall provided between the jig and the lifting means And have.

  Furthermore, in a method for manufacturing a semiconductor device according to another aspect of the present invention, a substrate holder holding a plurality of substrates in a vertical direction is accommodated in a processing chamber, and the substrate is processed at a predetermined processing gas and a predetermined temperature. And after the step of processing the substrate, the substrate holder is unloaded by a lifting / lowering means into a preliminary chamber disposed so as to communicate with the processing chamber in an airtight manner through the opening, and is unloaded into the preliminary chamber A cooling gas is supplied to the cooling wall provided between the substrate holder and the elevating means from a position facing the cooling wall to cool the substrate holder and the substrate, and the cooling gas collides with the cooling wall. And a step of causing

  According to the present invention, it becomes possible to provide a substrate processing apparatus, a substrate processing method, and a semiconductor device manufacturing method capable of shortening the temperature lowering time after the processing of the substrate and alleviating damage to components in the spare chamber due to radiant heat. Thus, it becomes possible to improve the throughput and form a good silicon carbide film.

It is a perspective view of the substrate processing apparatus used suitably by embodiment of this invention. It is a longitudinal cross-sectional view of the load-lock chamber in the substrate processing apparatus used suitably by embodiment of this invention. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. It is a perspective view which shows roughly the cooling wall used suitably by embodiment of this invention. It is the schematic explaining the structure of the cooling wall used suitably by embodiment of this invention. It is a perspective view which shows an example of the cooling nozzle used suitably by embodiment of this invention. It is a block diagram which shows the control structure of the substrate processing apparatus used suitably by embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The substrate processing apparatus according to the present embodiment will be described by taking a semiconductor manufacturing apparatus used for manufacturing a semiconductor device (IC (Integrated Circuit)) made of a substrate as an example. In the following description, a case where a vertical apparatus that performs heat treatment or the like on a wafer is used as an example of a substrate processing apparatus will be described.

  An example of a substrate processing apparatus in which the present invention is implemented will be described with reference to FIG. In this substrate processing apparatus 1, a wafer 6, which is a SiC substrate, is stored in a cassette 2 as a substrate storage container, and is carried in and out.

  The substrate processing apparatus 1 includes a housing 3, and a cassette loading / unloading port 4 is provided on the front wall of the housing 3 so as to be opened and closed by a front shutter (not shown). Inside the housing 3, a cassette stage 5 is provided adjacent to the cassette loading / unloading port 4.

  The cassette 2 is loaded onto the cassette stage 5 by an in-process transfer device (not shown) and unloaded from the cassette stage 5. The cassette stage 5 is arranged so that the wafer 6 in the cassette 2 is in a vertical posture and the wafer entrance / exit of the cassette 2 faces upward by the in-process transfer device. 3 Rotate to face backwards.

  A cassette shelf (substrate storage container mounting shelf) 7 is installed at a substantially central portion in the front-rear direction in the housing 3. The cassette shelf 7 stores a plurality of cassettes 2 in a plurality of rows and a plurality of rows. Is configured to do. The cassette shelf 7 is provided with a transfer shelf 9 in which the cassette 2 to be transferred by the wafer transfer device 8 is stored. Further, a preliminary cassette shelf 11 is provided above the cassette stage 5, and is configured to store the cassette 2 preliminarily.

  A cassette carrying device 12 is installed between the cassette stage 5 and the cassette shelf 7. The cassette carrying device 12 is configured to carry the cassette 2 between the cassette stage 5, the cassette shelf 7, and the spare cassette shelf 11.

  A wafer transfer device 8 is installed behind the cassette shelf 7. The wafer transfer device 8 is provided on the wafer transfer mechanism 8a capable of rotating or linearly moving the wafer 6 in the horizontal direction, an elevating mechanism 8b for raising and lowering the wafer transfer mechanism 8a, and the wafer transfer mechanism 8a. And a tweezer 8c for picking up the wafer 6.

  Behind the wafer transfer device 8, a processing furnace 14 for heat-treating the wafer 6 and a load lock chamber 15 for temporarily storing the wafer 6 before and after the heat treatment are provided adjacent vertically. In the load lock chamber 15, an elevating mechanism 16 that elevates the boat 13 to the processing furnace 14 is provided. The boat 13 includes a plurality of holding members, and is configured to hold a plurality of (for example, about 50 to 150) wafers 6 horizontally with the centers thereof aligned in the vertical direction. ing.

  The elevating mechanism 16 includes an elevating arm 17, and a seal cap 18 as a lid is provided horizontally on the elevating arm 17. The seal cap 18 supports the boat 13 vertically, and the furnace port of the processing furnace 14. The part is configured to open and close.

  Above the cassette shelf 7, a clean unit 19 for supplying clean air, which is a cleaned atmosphere, is provided, and the clean unit 19 distributes clean air inside the housing 3.

  Next, the details of the load lock chamber of the present embodiment will be described with reference to FIGS. 2 and 3 are schematic configuration diagrams for explaining a load lock chamber and members attached thereto used in a preferred embodiment of the present invention. In particular, FIG. 2 is a longitudinal sectional view of the load lock chamber. 3 is a cross-sectional view taken along line AA in FIG.

  As shown in FIGS. 2 and 3, the load lock chamber 15 is an example of a spare chamber capable of accommodating the boat 13 on which the semiconductor wafer 6 such as Si is mounted. The load lock chamber 15 is connected to the processing chamber of the processing furnace 14 through the opening 20. It is arranged to communicate in an airtight manner. An elevating mechanism 16 for elevating the boat 13 is provided in the load lock chamber 15. A cooling wall 23 is provided in the load lock chamber 15 so as to be divided into an elevating mechanism chamber 21 that accommodates the elevating mechanism 16 and a boat chamber 22 that accommodates the boat 13.

  For example, as shown in FIGS. 5A and 5B, the cooling wall 23 is configured by providing a flow passage 23 y for circulating a coolant (for example, water) inside a metal plate 23 x having good thermal conductivity. The cooling wall 23 includes a first cooling wall 23a provided at the center in the width direction in the load lock chamber 15, and a second cooling wall 23b provided on one side in the width direction. The first cooling wall 23 a and the second cooling wall 23 b are fixed in the load lock chamber 15. A slit 70 is provided between the first cooling wall 23a and the second cooling wall 23b so that one side of a flat U-shaped arm 41 described later can be moved up and down.

  An opening 25 is provided on one side wall 24 a of the load lock chamber 15 on the boat chamber 22 side, and a gate valve 26 is attached to the opening 25. In the substrate processing apparatus 1, the wafer 6 can be mounted on the boat 13 and the wafer 6 can be taken out from the boat 13 through the opening 25 and the gate valve 26.

  A processing furnace 14 is provided on the load lock chamber 15. The processing furnace 14 has a processing chamber (not shown) in which the boat 13 can be accommodated, and heating means (not shown) such as a heater for heating the processing chamber. The mounted wafer 6 can be heat-treated.

  An opening 20 is provided in the ceiling wall 27 between the processing furnace 14 and the boat chamber 22, and a gate valve 28 is attached to the opening 20. In the substrate processing apparatus 1, the boat 13 can be introduced into the processing chamber of the processing furnace 14 from the load lock chamber 15 or taken out from the processing chamber of the processing furnace 14 through the opening 20 and the gate valve 28. It is like that.

  The lifting mechanism chamber 21 is provided with a lifting mechanism 16 that moves the boat 13 in the vertical direction. The elevating mechanism 16 includes a moving block 30, a ball screw 31, a guide 32, bearings 33 and 34, a motor 35, and a magnetic seal unit 36 as main components. The ball screw 31 and the guide 32 are provided vertically between a base 38 attached to the bottom wall 37 and a base 39 attached to the ceiling wall 27. The lower end of the ball screw 31 is rotatably supported by a bearing 34 attached in the base 38, and the upper end of the ball screw 31 is rotatably supported by a bearing 33 attached in the base 39. Is attached to a magnetic seal unit 36.

  The ball screw 31 is connected to the motor 35 via the magnetic seal unit 36. When the ball screw 31 is rotated by the operation of the motor 35, the moving block 30 integrated with the nut 40 screwed to the ball screw 31 moves up and down, and thereby the arm 41 attached to the moving block 30 moves up and down. The boat 13 is moved up and down.

  The boat 13 is placed on a seal cap 18 attached on the arm 41. The arm 41 has a plane U shape, and the first cooling wall 23 a is disposed inside the arm 41. A second cooling wall 23 b is disposed on one side of the arm 41. The moving block 30 is provided with a guide hole 42 for the guide 32 in addition to the nut 40, and the nut 40 cooperates with the guide 32 to guide the vertical movement of the moving block 30.

  In the present embodiment, the ball screw 31, the guide 32, and the bearings 33 and 34 are described as being installed in the elevating mechanism chamber 21, but these elevating mechanisms may be provided outside the elevating mechanism chamber 21. When the elevating mechanism is provided outside, a member serving as an elevating shaft may be attached to the ball screw 31 or the guide 32, and the arm 41 may be attached to the elevating shaft.

  As shown in FIGS. 5A and 5B, the cooling wall 23 is made of a metal plate 23x made of a material having good thermal conductivity, for example, aluminum, and a coolant (for example, water) flows through the metal plate 23x. The flow path 23y is arranged. In addition, it is preferable that the surface of the metal plate 23x has a surface color with good heat absorption (for example, black).

An inert gas supply line 44 that supplies an inert gas such as a cooling gas (for example, N ₂ ) to the load lock chamber 15 is connected to the side wall 24c on one end side of the load lock chamber 15 as a cooling gas supply unit. Yes. The inert gas supply line 44 includes inert gas supply pipes 44a to 44f. The inert gas supply pipe 44a is branched into two inert gas supply pipes 44b and 44c. Each of the inert gas supply pipes 44b and 44c penetrates the side wall 24c and reaches the load lock chamber 15, and the inert gas supply pipe that is an inert gas supply section extending in the vertical direction in the load lock chamber 15 is provided. 44d and 44e. The inert gas supply pipes 44d and 44e are each provided with a plurality of injection holes 45 in the vertical direction.

  FIG. 6 is a perspective view showing an example of the inert gas supply pipes 44d and 44e. Upper and lower portions of the left and right inert gas supply pipes 44d and 44e are held by holding frames 51a and 51b. The inert gas is injected and supplied to the base side of the boat 13 from the injection holes 45 of the inert gas supply pipes 44d and 44e of the portions held by the upper and lower holding frames 51a and 51b. One inert gas supply pipe 44d has an extension 44dw extending upward from the upper holding frame 51a, and the inert gas is supplied to the wafer 6 on the boat 13 from the injection hole 45 of the extension 44dw. It is designed to supply the spray.

  A flow meter 59 is provided in the middle of the inert gas supply line 44 so that the amount of inert gas supplied from the inert gas supply line 44 to the load lock chamber 15 can be adjusted. The inert gas flowing in from the inert gas supply line 44 is supplied toward the boat 13 and the wafer 6 by the shower method from the injection holes 45 of the inert gas supply pipes 44d and 44e. Collides with the first cooling wall 23a and the second cooling wall 23b.

  The inert gas is at room temperature, but may be cooled. The inert gas cools the boat 13 and the wafer 6 as they pass through, and heats them up by taking heat away from them. Immediately thereafter, the inert gas cools down by colliding with the first cooling wall 23a and the second cooling wall 23b. Is done. A gap 46 is formed between the other side wall 24b of the load lock chamber 15 and the first cooling wall 23a so that an inert gas can flow from the boat chamber 22 side to the lifting mechanism chamber 21 side.

  The cooling wall 23 is arranged so as to partition the preliminary chamber 15 into an elevating mechanism chamber 21 that accommodates the elevating mechanism 16 and a boat chamber 22 that accommodates the boat 13, and the inert gas supply line 44 is connected to the cooling wall 23. It is supplied and collides with the cooling wall 23 and is cooled by the cooling wall 23 when reflected to the boat chamber 22 side.

  The side wall 24d on the other end side of the load lock chamber 15 is provided with a vacuum exhaust line 47 penetrating therethrough. An air valve 48 is provided in the middle of the vacuum exhaust line 47. An atmospheric pressure vent line 49 is connected to the front side of the air valve 48 of the vacuum exhaust line 47. The tip of the atmospheric pressure vent line 49 is substantially at atmospheric pressure.

  An air valve 50 is provided in the middle of the atmospheric pressure vent line 49. In the substrate processing apparatus 1, the air can be switched between the vacuum exhaust line 47 and the atmospheric pressure vent line 49 by the air valves 48 and 50. A vacuum pump (not shown) is connected to the vacuum exhaust line 47.

  The processing furnace 14 is connected to a gas supply line for supplying a processing gas to the processing chamber of the processing furnace 14 and an inert gas supply line for supplying an inert gas to the processing chamber, and the air valve is opened. When the vacuum pump is operated in this state, the gas atmosphere in the processing chamber can be exhausted from the vacuum exhaust line while supplying the processing gas or the inert gas into the processing chamber (not shown).

  In the substrate processing apparatus 1, the control unit 57 controls the heating means and the gas supply line for the processing furnace 14, the air valves 48 and 50, the vacuum pump, the flow meter 59, the pressure gauge 60, and the like. Information, pressure information from the pressure gauge, and the like are displayed on the display device 58 via the control device 57.

  The control configuration of each part constituting the substrate processing apparatus 1 for forming the SiC epitaxial film will be described. As shown in FIG. 7, the temperature control unit 52, the gas flow rate control unit 53, the pressure control unit 54, and the drive control unit 55 are An operation unit and an input / output unit are configured and electrically connected to a main control unit 56 that controls the entire substrate processing apparatus 1. Further, the temperature control unit 52, the gas flow rate control unit 53, the pressure control unit 54, and the drive control unit 55 are configured as a control device 57.

  Next, a method for forming a film on the wafer 6 using the substrate processing apparatus 1 having the above-described configuration will be described. In the substrate processing apparatus 1, the control unit 57 controls the heating means and the gas supply line related to the processing furnace 14, the air valves 48 and 50, the vacuum pump, the flow meter 59, the pressure gauge 60, and the like. Flow rate information, pressure information from the pressure gauge 60, and the like are displayed on the display device 58 via the control device 57.

(Step S1)
First, the processing chamber of the processing furnace 14 is maintained at a predetermined temperature and atmosphere with the gate valve 28 closed. In this state, the gate valve 26 is opened. At this time, the air valves 48 and 50 are closed. Thereafter, a plurality of wafers 6 are mounted on the boat 13 from the atmospheric pressure atmosphere outside the load lock chamber 15 through the opening 25 and the gate valve 26.

(Step S2)
Thereafter, the gate valve 26 is closed. While the air valve 50 is closed, the air valve 48 is opened, and the load lock chamber 15 is evacuated through the vacuum exhaust line 47.

(Step S3)
Thereafter, the air valve 48 is closed, and an inert gas is supplied from the inert gas supply line 44 until the inside of the load lock chamber 15 becomes atmospheric pressure or higher, thereby bringing the load lock chamber 15 into an inert gas atmosphere. Thereafter, with the inert gas supplied from the inert gas supply line 44, the air valve 50 is opened and the inert gas is exhausted from the atmospheric pressure vent line 49.

At this time, in order to prevent the backflow of particles and oxygen from the atmospheric pressure vent line 49, the flow meter 59 is set so that the inside of the load lock chamber 15 is slightly positive pressure (about 0.05 kgf / cm ² G) from the atmospheric pressure. Is used to control the flow rate of the inert gas supplied from the inert gas supply line 44. Control of the flow rate of the flow meter 59 is performed by the control device 57 in accordance with pressure information in the load lock chamber 15 input from the pressure gauge 60.

(Step S4)
Thereafter, the inert gas is exhausted from the atmospheric pressure vent line 49 while supplying the inert gas from the inert gas supply line 44. In this state, the gate valve 28 is opened, and the boat 13 is lifted by the lifting mechanism 16 and introduced into the processing chamber of the processing furnace 14.

  When opening the gate valve 28, the pressure information in the load lock chamber 15 from the pressure gauge 60 is input to the control device 57, and the measured pressure value in the load lock chamber 15 and a predetermined pressure value set in advance or The pressure value in the processing chamber of the processing furnace 14 is compared with the pressure value in the processing chamber 14 and the pressure in the load lock chamber 15 is controlled by controlling the flow meter 59 with the control device 57. The pressure is controlled so as to eliminate the pressure difference as much as possible. The pressure in the load lock chamber 15 can be adjusted by providing a flow meter in the atmospheric pressure vent line 49 and adjusting the flow rate of the atmospheric pressure vent line 49.

As described above, when the inert gas is exhausted from the atmospheric pressure vent line 49 while supplying the inert gas from the inert gas supply line 44, in order to prevent the backflow of particles and oxygen from the atmospheric pressure vent line 49. It is desirable to set the inside of the load lock chamber 15 to be slightly positive pressure (about 0.05 kgf / cm ² G) from the vent side (substantially atmospheric pressure).

  When the gate valve 28 is opened and the boat 13 is introduced into the processing chamber of the processing furnace 14 (boat loading), the inner wall of the load lock chamber 15 receives radiant heat leaking from the processing chamber of the processing furnace 14. Is blocked by the room temperature boat 13 and the wafer 6 mounted on the boat 13, and the rise in the surface temperature of the load lock chamber 15 is suppressed.

(Step S5)
Thereafter, the gate valve 28 is closed, the wafer 6 mounted on the boat 13 is heated while supplying a processing gas in the processing chamber of the processing furnace 14, and a film forming process is performed on the wafer 6. During the film forming process, in the load lock chamber 15, the inert gas is exhausted from the atmospheric pressure vent line 49 while supplying the inert gas from the inert gas supply line 44.

At that time, in order to prevent the backflow of particles and oxygen from the atmospheric pressure vent line 49, the flow meter 59 is used so that the load lock chamber 15 is slightly positive pressure (about 0.05 kgf / cm ² G) from the atmospheric pressure. The flow rate of the inert gas supplied from the inert gas supply line 44 is controlled. In step S5, the wafer 6 is formed in the processing chamber of the processing furnace 14 as described above, but it is important to strictly control the temperature and pressure in the processing chamber of the processing furnace 14 as the film forming conditions. .

  In the present embodiment, an inert gas ballast system is adopted as a pressure control method in the processing chamber of the processing furnace 14. In the “inert ballast system”, while exhausting the vacuum pump at a constant exhaust capacity, an inert gas is introduced from an inert gas ballast pipe connected in the middle of the vacuum exhaust line 47, and the inert gas In this method, the pressure in the processing chamber of the processing furnace 14 is adjusted by adjusting the exhaust amount from the processing chamber of the processing furnace 14 by controlling the flow rate with a flow meter.

  In place of the inert gas ballast method, a flow rate adjusting valve use (APC) method may be used. The “APC system” does not introduce inert gas from the inert gas ballast pipe, but a flow adjustment valve is provided in the vacuum exhaust line 47, and the conductance of the vacuum exhaust line 47 is adjusted by the opening of the flow adjustment valve. In this method, the pressure in the processing chamber of the processing furnace 14 is adjusted.

(Step S6)
After the film forming process in the processing chamber of the processing furnace 14 is completed, the atmosphere in the processing chamber of the processing furnace 14 is changed to an inert gas atmosphere. On the other hand, while the inert gas is being supplied from the inert gas supply line 44 into the load lock chamber 15, the exhaust gas is continuously exhausted from the atmospheric pressure vent line 49 to maintain the load lock chamber 15 in an inert gas atmosphere. deep.

  In this state, the gate valve 28 is opened, the boat 13 is lowered by the elevating mechanism 16 and moved from the processing chamber of the processing furnace 14 into the load lock chamber 15, and then the gate valve 28 is closed. In the load lock chamber 15, the inert gas (cooling gas) is supplied from the inert gas supply line 44. Therefore, when the boat 13 moves to the load lock chamber 15, the inert gas is mounted on the boat 13 and the boat 13. The wafer 6 and the like are cooled.

  When opening the gate valve 28, the pressure in the load lock chamber 15 is controlled by controlling the flow rate of the flow meter 59, and the pressure difference between the processing chamber of the processing furnace 14 and the load lock chamber 15 is set. It is preferable to control the pressure as much as possible.

  When the gate valve 28 is opened and the boat 13 descends from the processing chamber of the processing furnace 14 to the load lock chamber 15 (boat unloading) or stays in the load lock chamber 15 after descending, the boat 13 and the boat 13 are mounted thereon. The wafer 6 and the like generate radiant heat, but the load lock chamber 15 is provided with a cooling wall 23 on one side and the inert gas supply pipes 44d and 44e on the other side with the boat 13 in between. Since the inert gas, which is a cooling gas, is injected from the injection holes 45 of the tubes 44d and 44e onto the boat 13 and the wafer 6 mounted thereon, the temperature of the radiant heat from the boat 13 and the wafer 6 can be effectively lowered. The parts such as the inner wall of the load lock chamber 15 and various sensors are hardly affected by radiant heat.

  The inert gas supplied from the inert gas supply line 44 is warmed by receiving radiant heat. However, since the inert gas is cooled by colliding with the cooling wall 23, it is mounted on the boat 13 and the boat. The radiant heat from the wafer 6 can be taken again to cool them efficiently.

(Step S7)
After that, while supplying the inert gas from the inert gas supply line 44 and exhausting the inert gas from the atmospheric pressure vent line 49, the gate valve 26 is opened, and the boat 13 is opened via the opening 25 and the gate valve 26. The plurality of wafers 6 are taken out into the atmospheric pressure atmosphere outside the load lock chamber 15. Even when the gate valve 26 is opened, the pressure in the load lock chamber 15 is controlled by controlling the flow rate of the flow meter 59, and the pressure difference between the load lock chamber 15 and the atmospheric pressure atmosphere outside the load lock chamber 15 is controlled. It is preferable to eliminate as much as possible.

  In the above embodiment, the cooling wall 23 is disposed in the load lock chamber 15, and when the heat-treated wafer 6 is cooled in the load lock chamber 15, the boat is formed from the injection holes 45 of the inert gas supply pipes 44 d and 44 e. Since the inert gas is injected and supplied to the wafer 13 and the wafer 6 mounted thereon, the inside of the boat 13 and the wafer 6 and the load lock chamber 15 can be quickly cooled, and the inner wall of the load lock chamber 15 and components such as various sensors Class receives almost no radiant heat from the boat 13 and the wafer 6. For this reason, even if moisture or impurities adhere to the inner wall of the load lock chamber 15, these moisture and impurities do not evaporate and float in the load lock chamber 15. Damage can also be reduced for each component that has not been heat-treated.

  Further, the inert gas supplied from the injection holes 45 of the inert gas supply pipes 44d and 44e collides with the first cooling wall 23a and the second cooling wall 23b constituting the cooling wall 23 after passing through the boat 13 and the wafer 6. Therefore, the first cooling wall 23a and the second cooling wall 23b are used for cooling. And the inert gas (cooling gas) which collided with the 1st cooling wall 23a and the 2nd cooling wall 23b and reflected in the boat chamber 22 cooled the boat chamber 22 again, and the 1st cooling wall 23a and the 2nd cooling wall The elevating mechanism chamber 21 flows into the elevating mechanism chamber 21 through the slit 70 and the gap 46 of 23 b to cool the elevating mechanism 16, and is exhausted from the elevating mechanism chamber 21 through the atmospheric pressure vent line 49.

  As described above, the atmosphere in the load lock chamber 15 can be effectively cooled and exhausted by the inert gas, so that boat unloading at a high temperature is possible, and thermal convection in the load lock chamber 15 is prevented. Even if moisture, impurities, etc. adhering to the inner wall of the load lock chamber 15 float in the load lock chamber 15 and are mixed with the inert gas, the moisture, impurities, etc. It becomes difficult to scatter in the load lock chamber 15.

  From the above, it is possible to prevent or inhibit moisture, impurities, etc. adhering to the inner wall of the load lock chamber 15 from adhering to the wafer 6 after heat treatment, the boat 13 on which it is mounted, etc. 6 can be prevented or suppressed from being contaminated.

  In the above-described embodiments, the SiC epitaxial film forming apparatus has been described. However, in the SiC annealing apparatus, which is a heat treatment apparatus having the same configuration, various sensors for detecting whether the furnace port is sealed around the furnace port. In addition, unlike other film types, the substrate processing temperature is as high as 1500 to 2000 ° C., so the temperature around the furnace port becomes higher than that of a normal vertical apparatus. Can be prevented from being easily broken.

  Since the substrate processing temperature is high, it takes time to lower the temperature, so it is necessary to unload the boat at a temperature as high as possible, for example, 1000 ° C. However, if the unloading is performed at a high temperature, the load lock chamber is provided. Each part cannot withstand radiant heat from boats and wafers. Therefore, when the boat is down, the pressure in the load lock chamber 15 is equal to the atmospheric pressure, and the pressure in the load lock chamber 15 is increased by supplying the cooling gas. High temperature atmosphere can be pushed out quickly.

  As described above, it is possible to shorten the temperature drop time after the processing of the wafer and alleviate damage to components in the load lock chamber due to radiant heat. That is, in the prior art, it took about 2 hours from boat unloading (about 1000 ° C.) to taking out the wafer (about 100 ° C.), but according to the present embodiment, it takes about 1/5 time. It became possible to shorten. In addition, it is possible to protect the components (sensors and the like) in the load lock chamber 15 from thermal damage. Furthermore, the occurrence of metal contamination and organic contamination due to heat in the load lock chamber can be suppressed.

  The above is only one preferred embodiment of the present invention, and the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the present invention. For example, the present invention can be applied not only to a semiconductor wafer but also to a glass substrate load lock chamber for forming a liquid crystal display element.

  For example, in the present embodiment, the description has been given using the vertical batch type substrate processing apparatus. However, a space (cooling chamber) for cooling the substrate carried out of the processing chamber is provided in the single wafer processing apparatus, and the configuration described above is provided. Needless to say, it can be applied by providing.

  As mentioned above, although this invention has been demonstrated along embodiment, the main aspect of this invention is added here.

[Appendix 1]
A substrate holder for holding a plurality of substrates;
A processing chamber for storing the substrate holder and processing the substrate;
A preparatory chamber that is arranged to communicate with the processing chamber in an airtight manner through the opening, accommodates the substrate holder, and transfers a substrate;
Elevating means for elevating and lowering the substrate holder between the processing chamber and the preliminary chamber;
A cooling wall disposed between the lifting means and the substrate holder in the preliminary chamber;
A substrate processing apparatus, comprising: a cooling gas supply unit that is provided at a position facing the cooling wall with the substrate holder interposed therebetween, and supplies a cooling gas to the substrate holder and the substrate and then collides with the cooling wall.

[Appendix 2]
The cooling wall is disposed so as to partition the preliminary chamber into an elevating mechanism chamber that accommodates the elevating mechanism and a substrate holder chamber that accommodates the substrate holder, and the cooling wall from the cooling gas supply unit to the cooling wall The substrate processing apparatus according to appendix 1, wherein the substrate processing apparatus is cooled by the cooling wall when it is supplied, collides with the cooling wall, and is reflected to the substrate holder chamber side.

[Appendix 3]
The substrate processing apparatus according to appendix 1 or 2, wherein the substrate is processed at 1500 to 2000 ° C.

[Appendix 4]
Accommodating a substrate holder holding a plurality of substrates in a processing chamber and processing the substrate;
After the step of processing the substrate, a step of lifting the substrate holder by a lifting means to a preliminary chamber disposed so as to communicate with the processing chamber in an airtight manner through the opening;
A cooling gas is supplied from a position facing the cooling wall to the cooling wall provided between the substrate holder carried out to the preliminary chamber and the elevating means to cool the substrate holder and the substrate. And a step of causing the cooling gas to collide with the cooling wall.

[Appendix 5]
The substrate processing method according to appendix 4, wherein the step of heat-treating the substrate in the processing chamber is performed at 1500 to 2000 ° C.

[Appendix 6]
Accommodating a substrate holder holding a plurality of substrates in a processing chamber and processing the substrate;
After the step of processing the substrate, a step of lifting the substrate holder by a lifting means to a preliminary chamber disposed so as to communicate with the processing chamber in an airtight manner through the opening;
A cooling gas is supplied from a position facing the cooling wall to the cooling wall provided between the substrate holder carried out to the preliminary chamber and the elevating means to cool the substrate holder and the substrate. A method of manufacturing a semiconductor device, the method comprising: causing a cooling gas to collide with a cooling wall.

[Appendix 7]
A step of carrying the substrate into the processing chamber;
Heat treating the substrate in the processing chamber;
After the step of processing the substrate, a step of lifting the substrate holder by a lifting means to a preliminary chamber disposed so as to communicate with the processing chamber in an airtight manner through the opening;
A cooling gas is supplied from a position facing the cooling wall to the cooling wall provided between the substrate holder carried out to the preliminary chamber and the elevating means to cool the substrate holder and the substrate. And a step of causing the cooling gas to collide with the cooling wall.

[Appendix 8]
The method for manufacturing a substrate according to appendix 7, wherein the step of heat-treating the substrate in the processing chamber is performed at 1500 to 2000 ° C.

1 Substrate Processing Device 6 Wafer (Substrate)
13 Boat (Substrate holder)
14 Processing furnace 15 Load lock room (spare room)
16 Lifting mechanism (lifting means)
21 Elevating mechanism chamber 22 Substrate holder chamber 23 Cooling wall 44 Inert gas supply line (cooling gas supply section)

Claims (3)

A substrate holder for holding a plurality of substrates;
A processing chamber for storing the substrate holder and processing the substrate;
A preparatory chamber that is arranged to communicate with the processing chamber in an airtight manner through the opening, accommodates the substrate holder, and transfers a substrate;
Elevating means for elevating and lowering the substrate holder between the processing chamber and the preliminary chamber;
A cooling wall disposed between the lifting means and the substrate holder in the preliminary chamber;
A substrate processing apparatus, comprising: a cooling gas supply unit that is provided at a position facing the cooling wall with the substrate holder interposed therebetween, and supplies a cooling gas to the substrate holder and the substrate and then collides with the cooling wall. Accommodating a substrate holder holding a plurality of substrates in a processing chamber and processing the substrate;
After the step of processing the substrate, a step of lifting the substrate holder by a lifting means to a preliminary chamber disposed so as to communicate with the processing chamber in an airtight manner through the opening;
A cooling gas is supplied from a position facing the cooling wall to the cooling wall provided between the substrate holder carried out to the preliminary chamber and the elevating means to cool the substrate holder and the substrate. And a step of causing the cooling gas to collide with the cooling wall. Accommodating a substrate holder holding a plurality of substrates in a processing chamber and processing the substrate;
After the step of processing the substrate, a step of lifting the substrate holder by a lifting means to a preliminary chamber disposed so as to communicate with the processing chamber in an airtight manner through the opening;
A cooling gas is supplied from a position facing the cooling wall to the cooling wall provided between the substrate holder carried out to the preliminary chamber and the elevating means to cool the substrate holder and the substrate. A method of manufacturing a semiconductor device, the method comprising: causing a cooling gas to collide with a cooling wall.

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