WO2019038974A1

WO2019038974A1 - Substrate processing device, reaction tube, substrate processing method, and semiconductor device production method

Info

Publication number: WO2019038974A1
Application number: PCT/JP2018/011730
Authority: WO
Inventors: 優作岡嶋; 隆史佐々木; 吉田　秀成; 英俊三村; 石坂　光範; 周平西堂
Original assignee: 株式会社ＫｏｋｕｓａｉＥｌｅｃｔｒｉｃ
Priority date: 2017-08-25
Filing date: 2018-03-23
Publication date: 2019-02-28
Also published as: JP6867496B2; JPWO2019038974A1

Abstract

This invention makes it possible to equalize speed distribution of processing gas among substrates. This substrate processing device is equipped with a reaction tube having cylindrical outer and inner tubes with a closed upper end. The inner tube has a first gas exhaust port provided parallel to the central axis of the inner tube, and the outer tube has an exhaust outlet. The first gas exhaust port comprises: a first width section provided at the farthest position from the exhaust outlet; a second width section provided at a position closer to the exhaust outlet compared to the first width section and formed so that, substantially, the width thereof is equal to or narrower than the width of the first width section; and a third width section having a narrower width than the first width section and the second width section on the second width section side between the first width section and the second width section.

Description

Substrate processing apparatus, reaction tube, substrate processing method, and method of manufacturing semiconductor device

The present disclosure relates to a substrate processing apparatus, and more particularly to a substrate processing apparatus having a vertical reaction tube.

A semiconductor manufacturing apparatus is known as an example of a substrate processing apparatus, and a vertical type apparatus is known as an example of a semiconductor manufacturing apparatus. As a substrate processing apparatus of this type, a boat serving as a substrate holding member for holding substrates (wafers) in multiple stages is provided in a reaction tube, and a substrate is processed in a processing chamber in the reaction tube while holding a plurality of substrates. There is something to do.

In this type of reaction tube structure, the flow velocity difference of the processing gas is easily generated in the vertical direction in the substrate processing region, which causes the generation of the film thickness difference between the wafers. Patent documents 1 to 4 have been proposed as techniques for making the velocity distribution of processing gas between wafers uniform.

Design registration No. 1563524 gazette Unexamined-Japanese-Patent No. 9-330884 JP 2005-209668 A JP, 2010-258265, A

The inventors of the present invention have made the shape of the exhaust hole provided in the inner tube of the double reaction tube, and the exhaust outlet provided in the outer tube of the double reaction tube as a technique for making the velocity distribution of processing gas between wafers uniform. Further study was conducted on the relationship between As a result, in order to suppress the inclination of the flow of the processing gas concentrated to the exhaust outlet side, when the shape of the exhaust hole is narrowed toward the exhaust outlet side (substantially inverse triangle shape), the constant distance away from the exhaust outlet side The flow of the processing gas in the range of is substantially uniform. However, it has been found that there is a flow of processing gas flowing into the space other than the wafer processing space of the inner pipe in the inner pipe at a location near the exhaust outlet.
For this reason, even when the shape of the exhaust hole is narrowed toward the exhaust outlet (for example, a substantially inverted triangular shape), the velocity distribution of the processing gas between the wafers becomes uneven, and the film thickness between the wafers It has been found that there is a risk of causing a difference.
An object of the present disclosure is to provide a technology capable of making the velocity distribution of processing gas between wafers uniform.
Other problems and novel features will be apparent from the description of the present specification and the accompanying drawings.

The outline of the present disclosure will be briefly described as follows.
That is, the substrate processing apparatus includes a reaction tube having a cylindrical inner tube and an outer tube whose upper ends are closed. The inner pipe has a first gas outlet provided parallel to the central axis of the inner pipe, and the outer pipe has an exhaust outlet. The first gas exhaust port is provided at a first width portion provided at a position relatively far from the exhaust outlet, and at a position closer to the exhaust outlet than the first width portion, and substantially Between the first width and the second width formed between the first width and the second width, and on the second width side, A first width portion and a third width portion having a smaller width than the second width portion.

According to the present invention, in the first gas exhaust port, the first width portion and the second width portion are disposed between the first width portion and the second width portion, and the first width portion and the second width portion are provided. Since the third width portion has a width smaller than the second width portion, it is possible to prevent the flow of the processing gas into the area other than the wafer processing space of the inner pipe. Thus, the velocity distribution of the processing gas between the wafers can be made uniform, so that the film thickness difference between the wafers can be made uniform.

It is a longitudinal cross-sectional view of the vertical processing furnace of the substrate processing apparatus which concerns on embodiment. It is a cross-sectional view of the reaction tube of a vertical processing furnace. It is a perspective sectional view of a reaction tube of a vertical processing furnace. It is a side view of a reaction tube explaining the shape of the first gas exhaust port 236. It is a longitudinal cross-sectional view which expands and shows the upper part of a reaction tube. It is a schematic block diagram of the controller of a substrate processing apparatus, and is a figure which shows the control system of a controller with a block diagram. It is a conceptual diagram explaining the flow of the gas in the reaction tube in the 1st gas exhaust port 236 demonstrated in FIG. It is a conceptual diagram explaining the flow of the gas in the reaction pipe in the 1st gas exhaust port 236P1 concerning comparative example 1. FIG. 18 is a conceptual diagram illustrating the flow of gas in the reaction tube at the first gas exhaust port 236P2 according to Comparative Example 2. It is a schematic diagram which compares and demonstrates the flow of the process gas to the exhaust port 230. FIG. It is a figure for demonstrating the relationship of the opening position of the 1st gas exhaust port 236 which concerns on embodiment, and the wafer 200. FIG. It is a figure which shows the shape of 1st gas exhaust port 236A which concerns on the modification 1. FIG. It is a figure which shows the shape of 1st gas exhaust port 236B which concerns on the modification 2. FIG. It is a figure which shows the shape of 1st gas exhaust port 236C which concerns on the modification 3. FIG. FIG. 16 is a view showing the shape of a first gas exhaust port 236D according to a modification 4; It is a figure which shows the shape of the 1st gas exhaust port 236E which concerns on the modification 5. FIG. It is a figure which shows the shape of 1st gas exhaust port 236F which concerns on the modification 6. As shown in FIG. FIG. 18 is a view showing the shape of a first gas exhaust port 236G according to Modification 7; It is the horizontal sectional view which looked at the reaction tube which concerns on the modification 8 from upper side. It is a bottom view of the reaction tube concerning modification 8. FIG. It is the vertical sectional view which looked at the reaction tube concerning modification 8 from the right side. It is the vertical sectional view which looked at the reaction tube concerning modification 8 from the back. .

Hereinafter, an embodiment, a comparative example, and a modification are described using a drawing. However, in the following description, the same components may be assigned the same reference numerals and repeated descriptions may be omitted. Note that the drawings may be schematically represented as to the width, thickness, shape, etc. of each portion in comparison with the actual embodiment in order to clarify the description, but this is merely an example, and the interpretation of the present invention is not limited. It is not limited.

Embodiment
Hereinafter, an embodiment of the present invention will be described with reference to FIG. The substrate processing apparatus 1 in the present invention is configured as an example of a semiconductor manufacturing apparatus used for manufacturing a semiconductor device.

As shown in FIG. 1, the vertical processing furnace 202 includes a reaction tube 203 forming a processing chamber 201 for processing the substrate 200, and a heater 207 is provided so as to surround the reaction tube 203. The heater 207 has a cylindrical shape and is vertically installed by being supported by a heater base (not shown) as a holding plate. The heater 207 is a heating unit (heating mechanism) of the processing chamber 201, and also functions as an activation mechanism (excitation unit) that activates (excites) the processing gas with heat.

The reaction tube 203 is coaxially disposed inside the heater 207, and constitutes a reaction container (processing container) of a pressure resistant structure. The reaction tube 203 is formed in a cylindrical shape, and the lower end is opened and provided with a flange, and the upper end is closed by a relatively thick flat ceiling member. Inside the reaction tube 203, a cylindrical portion 209 formed in a cylindrical shape, a nozzle disposition chamber 222 partitioned between the cylindrical portion 209 and the reaction tube 203, and a gas supply port formed in the cylindrical portion 209 (introduction A second gas exhaust port 237 formed under the first gas exhaust port 236 and formed in the cylindrical section 209 and a gas supply slit 235 as a port), a first gas exhaust port 236 formed in the cylindrical section 209, and Is equipped. The reaction tube 203 and the cylindrical portion 209 are made of, for example, a heat resistant material such as quartz (SiO 2) or silicon carbide (SiC). The reaction tube 203 and the tube portion 209 constitute a double reaction tube, the reaction tube 203 is an outer tube, and the tube portion 209 is an inner tube (liner tube). The first gas exhaust port 236 may be referred to as an exhaust hole or a slit. Further, the second gas exhaust port 237 may be referred to as a lower opening. The reaction tube 203 and the cylindrical portion 209 are integrally or separately configured, and when they are integrally formed, the lower end flange of the reaction tube 203 is also formed inward to be coupled to the cylindrical portion 209.

The processing chamber 201 is formed inside the cylindrical portion 209 of the reaction tube 203, and is configured to be able to process the wafer 200 as a substrate. In the processing chamber 201, a plurality of twenty-five or more wafers 200 can be held by the boat 217, which will be described later, in a horizontal posture in the vertical direction at a constant interval (pitch) p. The boat 217 is made of, for example, a heat resistant material such as quartz or SiC. The boat 217 has a bottom plate (not shown) and a top plate disposed above the bottom plate, and has a configuration in which a plurality of columns are bridged between the bottom plate and the top plate. The plurality of wafers 200 are held in a multistage manner in the axial direction of the reaction tube 203 in a state in which the horizontal attitude is maintained with the gap p provided and the centers are aligned with each other by the grooves provided in the support. The gap between the cylindrical portion 209 and the boat 217 is designed to be small as far as it can be operated safely, for example, 10 mm or a substrate, in order to suppress the flow of the processing gas which bypasses the substrate and to enhance the gas displaceability of the processing chamber. Less than the pitch of

The lower end of the reaction tube 203 is supported by a cylindrical manifold 226. The manifold 226 is made of, for example, a metal such as nickel alloy or stainless steel, or is made of a heat resistant material such as quartz or SiC. A flange is formed at the upper end of the manifold 226, and the lower end of the reaction tube 203 is installed and supported on the flange. An airtight member 220 such as an O-ring is interposed between the flange and the lower end portion of the reaction tube 203 to make the inside of the reaction tube 203 airtight. When the cylindrical portion 209 is configured separately from the reaction tube 203, the cylindrical portion 209 is fixed by the flange formed at the lower end thereof being engaged with the fixing tool provided inside the manifold 226.

A seal cap 219 is airtightly attached to the opening at the lower end of the manifold 226 via an airtight member 220 such as an O-ring, and the opening at the lower end of the reaction tube 203, that is, the opening of the manifold 226 is airtight. It is supposed to be closed. The seal cap 219 is made of, for example, a metal such as a nickel alloy or stainless steel, and is formed in a disk shape. The seal cap 219 may be configured to cover the outside with a heat resistant material such as quartz (SiO 2) or silicon carbide (SiC).

On the seal cap 219, a boat support (insulation cylinder) 218 for supporting the boat 217 is provided. The boat support 218 is made of, for example, a heat resistant material such as quartz or SiC, and functions as a heat insulating part and serves as a support for supporting the boat. The boat 217 is fixed on a boat support 218.

A boat rotation mechanism 267 for rotating the boat is provided on the opposite side of the seal cap 219 to the processing chamber 201. The rotation shaft 265 of the boat rotation mechanism 267 is connected to the boat support 218 through the seal cap, and the wafer rotation mechanism 267 rotates the wafer 200 by rotating the boat 217 via the boat support 218. . The boat 217 and the boat support 218 can be positioned by pins or the like so that the symmetry axes of the boat 217 and the boat support 218 exactly coincide with the rotation axis of the boat rotation mechanism 267.

The seal cap 219 is vertically moved up and down by a boat elevator 115 as an elevating mechanism provided outside the reaction tube 203, whereby the boat 217 can be carried into and out of the processing chamber 201.

In the manifold 226, nozzle support portions 350a to 350d for supporting the nozzles 340a to 340d as gas nozzles for supplying the processing gas into the processing chamber 201 are installed so as to penetrate the manifold 226. Here, four nozzle support portions 350a to 350d are provided. The nozzle support portions 350a to 350d are made of, for example, a material such as a nickel alloy or stainless steel. Gas supply pipes 310a to 310c for supplying a gas into the processing chamber 201 are connected to one end of the nozzle support portions 350a to 350c on the reaction pipe 203 side. Further, a gas supply pipe 311d for supplying a gas to the gap S formed between the reaction tube 203 and the cylindrical portion 209 is connected to one end of the nozzle support portion 350d on the reaction tube 203 side. The nozzles 340a to 340d are connected to the other ends of the nozzle support portions 350a to 350d, respectively. The nozzles 340a to 340d are made of, for example, a heat resistant material such as quartz or SiC.

In the gas supply pipe 310a, a first process gas supply source 360a for supplying a first process gas, a mass flow controller (MFC) 320a which is a flow rate controller (flow rate control unit) and a valve 330a which is an on-off valve. Are provided respectively. In the gas supply pipe 310b, a second processing gas supply source 360b, an MFC 320b, and a valve 330b for supplying the second processing gas are provided in this order from the upstream direction. In the gas supply pipe 310c, a third processing gas supply source 360c, an MFC 320c, and a valve 330c for supplying the third processing gas are provided in this order from the upstream direction. The gas supply pipe 311d is provided with an inert gas supply source 361d, an MFC 321d and a valve 331d for supplying an inert gas sequentially from the upstream direction.

Gas supply pipes

311a and 311b for supplying an inert gas are connected to the

gas supply pipes

310a and 310b on the downstream side of the

valves

330a and 330b, respectively. In the

gas supply pipes

311a and 311b, MFCs 321a and 321b and

valves

331a and 331b are provided in this order from the upstream direction.

A first processing gas supply system mainly includes the gas supply pipe 310a, the MFC 320a, and the valve 330a. The first process gas supply source 360a, the nozzle support portion 350a, and the nozzle 340a may be included in the first process gas supply system. In addition, a second processing gas supply system is mainly configured by the gas supply pipe 310 b, the MFC 320 b, and the valve 330 b. The second process gas supply system 360 may include the second process gas supply source 360b, the nozzle support 350b, and the nozzle 340b. In addition, a third processing gas supply system is mainly configured by the gas supply pipe 310c, the MFC 320c, and the valve 330c. The third process gas supply source 360c, the nozzle support portion 350c, and the nozzle 340c may be included in the third process gas supply system. In addition, an inert gas supply system is mainly configured by the gas supply pipe 311d, the MFC 321d, and the valve 331d. The inert gas supply source 361 d, the nozzle support portion 350 d, and the nozzle 340 d may be included in the inert gas supply system. In the present specification, when the term "processing gas" is used, when only the first processing gas is included, when only the second processing gas is included, when only the third processing gas is included, only the inert gas is included. Or all of them may be included. Moreover, when the term "process gas supply system" is used, when only the first process gas supply system is included, when only the second process gas supply system is included, when only the third process gas supply system is included, inert gas It may include only the feed system or it may include all of them.

An exhaust outlet (exhaust port) 230 is formed in the reaction tube 203. The exhaust outlet 230 is formed below the second gas exhaust port 237, and fluidly connects the inside of the reaction tube 203 (the gap S) to the exhaust tube 231. A vacuum is provided in the exhaust pipe 231 via a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as a pressure regulator (pressure adjustment unit). A vacuum pump 246 as an exhaust device is connected, and is configured to be able to evacuate so that the pressure in the processing chamber 201 becomes a predetermined pressure (degree of vacuum). The downstream side of the vacuum pump 246 can be connected to a waste gas processing device (not shown) or the like. The APC valve 244 opens and closes the valve to evacuate and stop the evacuation in the processing chamber 201. Further, the valve opening degree is adjusted to adjust the conductance so that the pressure in the processing chamber 201 can be adjusted. It is an on-off valve. An exhaust system that functions as an exhaust unit is mainly configured by the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may be included in the exhaust system.

In the reaction tube 203, for example, a temperature sensor (not shown) such as a thermocouple is installed as a temperature detector, and by adjusting the power supplied to the heater 207 based on the temperature information detected by the temperature sensor, The temperature in the processing chamber 201 is configured to have a desired temperature distribution. Further, a purge gas supply device 268 for supplying a gas for purging a space in the vicinity of the boat support 218 from the seal cap 219, which is referred to as a throat portion, is connected to the boat rotation mechanism 267. The purge gas supply device 268 includes the same configuration as the inert gas supply source 361 d, the MFC 321 d and the valve 331 d, and in this example, injects N ₂ gas near the shaft seal of the boat rotation mechanism 267.

In the processing furnace 202 described above, the boat 217 is inserted into the processing chamber 201 while being supported by the boat support base 218 in a state where the plurality of wafers 200 to be batch processed are stacked on the boat 217 in multiple stages, and the heater 207 is processed. The wafer 200 inserted into the chamber 201 is heated to a predetermined temperature.

Next, the configuration of the reaction tube 203 suitably used in the present embodiment will be described with reference to FIG. 2 to FIG. In addition, in FIG. 3, FIG. 4, description of the nozzle 340, the boat 217 grade | etc., Is abbreviate | omitted.

As shown in FIGS. 2 and 3, the cylindrical portion 209 is disposed coaxially with the reaction tube 203. A gap S is formed between the cylindrical portion 209 and the reaction tube 203. The gap S has an annular shape so as to surround the cylindrical portion 209 in a cross sectional view. On the opposite side of the space S to the exhaust outlet 230 (exhaust pipe 231), two partition plates 221 forming the nozzle disposition chamber 222 are provided parallel to the axis of the cylindrical portion 209 from the upper end to the lower end of the cylindrical portion 209 Be The nozzle disposition chamber 222 is formed to be divided between the wall of the cylindrical portion 209 and the wall of the reaction tube 203. The outer wall of the nozzle disposition chamber 222 doubles as the outer wall of the reaction tube 203, and is formed concentrically and with the same radius as the reaction tube 203. Further, the inner wall of the nozzle disposition chamber 222 doubles as the wall of the cylindrical portion 209 and is formed concentrically with the cylindrical portion 209 at the same radius. The lower end portion of the nozzle placement chamber 222 is opened, and a part (or all) of the upper end is closed by a flat wall (see FIG. 5). The upper end of the ceiling of the nozzle placement chamber 222 is at the same height as, or slightly lower than, the upper end of the ceiling of the cylindrical portion 209.

A partition plate 248 is formed inside the nozzle arrangement chamber to divide the nozzle arrangement indoor space into a plurality of spaces. In this example, two partition plates 248 are provided to divide the nozzle disposition chamber 222 from the vicinity of the lower end to the upper end side, and form three spaces separated from each other. Nozzles 340a to 340c are respectively installed in the respective spaces. The partition plates 221 and 248 are integrally formed of the same material as the cylindrical portion 209, but are not necessarily integrated (welded) with the reaction tube 203, and the harm due to gas leakage between the spaces is fatal It is sufficient if the space can be separated to such an extent that

A plurality of gas supply slits 235 for supplying the processing gas into the processing chamber 201 is formed at a position corresponding to the nozzle disposition chamber 222 of the cylindrical portion 209. For example, three gas supply slits 235 are arranged in the circumferential direction so as to communicate each space of the nozzle disposition chamber 222 with the processing chamber 201, and correspond to each surface (upper surface) of the wafer 200, for example. The individual openings are formed in the same number as the wafers 200 in the axial direction. That is, the gas supply slits 235 may be formed in a matrix of plural stages and plural rows in the vertical and horizontal directions. The gas supply slit 235 is formed with a plurality of horizontally long slits in the vertical direction.

The gas supply slit 235 is a slit elongated in the circumferential direction, and preferably the circumferential length is the same as the circumferential length of each space in the nozzle disposition chamber 222, because gas supply efficiency is improved. . In addition, preferably, the gas supply slit 235 may be formed in a plurality of horizontally long stages except for the connecting portion between the partition plate 248 and the wall of the cylindrical portion 209 because the gas supply efficiency is improved. The gas supply slits 235 can be formed smoothly so that the edge portions as the four corners have a curved surface. By performing R-edging or the like on the edge and making it curved, stress concentration can be alleviated and cracking can be prevented, and stagnation of gas around the edge can be suppressed, and the film to the edge can Formation and peeling of the film can be suppressed.

Such a configuration can increase the proportion of gas flowing into the wafer surface. Further, since the nozzles 340a to 340c are disposed in independent spaces by the partition plate 248, the processing gas supplied from the nozzles 340a to 340c is mixed in the nozzle disposition chamber 222 to form a thin film. And the generation of byproducts can be suppressed.

The nozzles 340a to 340c are provided above the lower part in the nozzle disposition chamber 222, and the nozzles 340d are provided above the lower part in the gap S in parallel with the axis (longitudinal direction) of the reaction tube 203. The nozzles 340a to 340d are respectively configured as long nozzles of a straight pipe. Gas supply holes 234a to 234d for supplying gas are respectively provided on side surfaces of the nozzles 340a to 340d. The gas supply holes 234 a to 234 c are opened toward the center of the reaction tube 203, and the gas supply holes 234 d are opened toward the circumferential direction of the reaction tube 203. As described above, three nozzles 340 a to 340 c are provided in the nozzle disposition chamber 222, and a plurality of types of gases can be supplied into the processing chamber 201.

Also, the nozzle 340 d is configured to be able to supply an inert gas (purge gas) into the gap S. With such a configuration, the back side of the cylindrical portion can be efficiently purged, retention of gas on the back side of the cylindrical portion can be suppressed, and the purge time can be shortened. Furthermore, the particles can be reduced by suppressing the retention of the gas on the back side of the cylindrical portion. In addition, by supplying the purge gas from the rear side of the cylindrical portion, the pressure increase in the processing chamber 201 during the high pressure process can be assisted.

A first gas exhaust port 236 is formed on the other side surface facing the one side surface where the nozzle disposition chamber 222 of the cylindrical portion 209 is formed. The first gas exhaust port 236 is disposed so as to sandwich an area in which the wafer 200 of the processing chamber 201 is accommodated between the first gas exhaust port 236 and the nozzle disposition chamber 222. The first gas exhaust port 236 is formed in a region (wafer region) from the lower end side of the processing chamber 201 where the wafer 200 is accommodated to the upper end side. Further, a second gas exhaust port 237 is formed on the side surface of the cylindrical portion 209 below the first gas exhaust port 236. That is, although both the first gas exhaust port 236 and the second gas exhaust port 237 communicate the processing chamber 201 with the gap S, they have different roles. That is, the first gas exhaust port 236 is an opening intended to exhaust the atmosphere in the processing chamber 201 evenly over the plurality of wafers 200, and the gas exhausted from the first gas exhaust port 236 is a gap. After spreading and lowering S, the gas is collected at the exhaust outlet 230 and exhausted from the exhaust pipe 231 to the outside of the reaction pipe 203. On the other hand, the second gas exhaust port 237 is formed to exhaust the atmosphere (mainly purge gas) under the wafer 200 processing chamber 201, particularly around the boat support 218. With such a configuration, by exhausting the gas after passing through the wafer using the entire gap S, the difference (pressure loss) between the pressure of the exhaust unit and the pressure of the wafer area can be reduced. The pressure in the wafer area can be lowered, the flow velocity in the wafer area can be increased, and film formation with limited surface reaction and relaxation of the loading effect can be expected.

FIG. 4 is a conceptual view for explaining the shape and the installation position of the first gas exhaust port 236. As shown in FIG. FIG. 4 is a conceptual front view when the reaction tube (outer tube) 203 and the cylindrical portion (inner tube) 209 are viewed from the direction of the exhaust outlet 230 provided in the reaction tube (outer tube) 203. With respect to the central axis CA of the cylindrical portion 209, the center line of the exhaust outlet 230 in the horizontal direction (X direction) coincides with the direction of the central axis CA. Further, the center of the exhaust outlet 230 in the horizontal direction (X direction) and the center of the second gas exhaust port 237 in the horizontal direction (X direction) are aligned with the central axis CA. That is, when viewed from the central axis CA of the cylindrical portion 209, the first gas exhaust port 236, the second gas exhaust port 237, and the exhaust outlet 230 are provided in the same direction. Further, the second gas exhaust port 237 and the exhaust port 230 are provided at substantially opposite positions.

The first gas exhaust port 236 is provided on the side surface of the cylindrical portion 209 substantially in parallel with the central axis CA of the cylindrical portion 209. That is, the longitudinal direction of the first gas exhaust port 236 is provided substantially parallel to the central axis CA of the cylindrical portion 209. The first gas exhaust port 236 is provided on the side surface of the cylindrical portion 209 above the exhaust outlet 230 and the second gas exhaust port 237 along the vertical direction (Y direction, vertical direction) of the cylindrical portion 209. The second gas exhaust port 237 is formed from a position higher than the upper end of the exhaust outlet 230 to a position higher than the lower end of the exhaust outlet 230.

In FIG. 4, 235 a indicated by a substantially rectangular dotted line indicates the outer periphery of the formation region of the plurality of gas supply slits 235 provided in the cylindrical portion (inner pipe) 209. The formation region 235 a of the gas supply slit 235 is provided at a position facing or substantially directly facing the first gas exhaust port 236. Further, the formation region 235 a of the gas supply slit 235 is provided on the wall of the cylindrical portion 209 opposite to the first gas exhaust port 236 when viewed from the central axis CA of the cylindrical portion 209.

In FIG. 4, the first gas exhaust port 236 is constituted by a single opening whose width continuously changes, and substantially the maximum width W1 (the first width W1) and substantially the maximum. It has a portion of a small width W3 (third width portion W3) and a portion of a predetermined width W2 (second width portion W2) substantially wider than the minimum width W3. The line Y1 indicates the position in the Y direction corresponding to the portion of the maximum width W1 of the first gas exhaust port 236. A line Y2 indicates the position in the Y direction corresponding to the portion of the minimum width W3 of the first gas exhaust port 236. A line Y3 indicates the position in the Y direction corresponding to the portion of the predetermined width W2 of the first gas exhaust port 236. Line Y 4 indicates the center position of the opening of the exhaust outlet 230 in the Y direction. In this example, the position of the line Y1 indicates the upper end of the first gas outlet 236, and the position of the line Y3 indicates the lower end of the first gas outlet 236. The exhaust outlet 230 provided on the side surface of the reaction pipe (outer pipe) 203 is provided closer to the lower end than the position of the predetermined width W 2 of the first gas exhaust port 236. Therefore, the width of the first gas exhaust port 236 is gradually narrowed or narrowed from the maximum width W1 to the minimum width W3 between the line Y1 and the line Y2, and then the minimum width between the line Y2 and the line Y3. It is gradually expanded from W3 to a predetermined width (W2) substantially wider than the minimum width (W3). Incidentally, the substantial width means, for example, the width in the case where the first gas exhaust ports are constituted by a plurality of openings as described later, or a single constant which is equal in conductance per unit height. It means the width when converted to the slit of the width. Hereinafter, the width of each portion of the first gas exhaust port will be used in the meaning of this substantial width.

As understood from FIG. 4, in this example, the width W1 of the upper end of the first gas exhaust port 236 is the maximum width, and the width W3 of the middle portion of the first gas exhaust port 236 is the minimum width. ing. The width W2 of the lower end of the first gas exhaust port 236 is narrower than the maximum width W1 and wider than the minimum width W3 (W1> W2> W3). That is, the first gas exhaust port (exhaust hole) 236 has a maximum width (W1) near the upper end (line Y1) of the cylindrical portion (inner pipe) 209 and is below the cylindrical portion (inner pipe) 209. A predetermined width (W3) having a minimum width (W3) near the end (line Y2) and a predetermined width (W3) wider than the minimum width (W3) at a lower end (line Y3) than the position (line Y2) to be the minimum width (W3) W2). The wide predetermined width (W2) can be the same value as the maximum width (W1), or a value between the maximum width (W1) and the minimum width (W3) (W1WW2> W3). ).

The position of the line Y1 is a position relatively far from the line Y4 as compared with the positions of the lines Y2 and Y3. That is, at a distance from the exhaust outlet 230, the portion having the maximum width (W1) of the first gas exhaust port (exhaust hole) 236 has a wide predetermined width (W2) of the first gas exhaust port (exhaust hole) 236 It is provided at a relatively long distance (L1) from the exhaust outlet 230 as compared with the part. Further, at a distance from the exhaust outlet 230, a portion having a wide predetermined width (W2) of the first gas exhaust port (exhaust port) 236 has a maximum width (W1) of the first gas exhaust port (exhaust port) 236. It is provided at a distance L3 (L3 <L1) relatively close to the exhaust outlet 230 as compared with the portion. The portion having the minimum width (W3) of the first gas exhaust port (exhaust hole) 236 is provided at a distance L2 (L1> L2> L3) relatively longer than the distance L3 and relatively shorter than the distance L1. Here, although the example in which the exhaust outlet 230 is formed on the lower side is described, it may be provided on the upper side. When the exhaust outlet 230 is provided on the upper side, the configuration of the first gas exhaust port 236 may be configured to be upside down.

Therefore, the inner pipe 209 has the first gas exhaust port 236 provided parallel to the central axis CA of the inner pipe 209, and the outer pipe 203 has the exhaust outlet 230. The first gas exhaust port 236 has a first width W1 provided at a position (L1) relatively far from the exhaust outlet 230 and a position closer to the exhaust outlet 230 than the first width W1 ( A second width portion W2 provided in L3) and formed substantially equal to or less than the width of the first width portion W1, and between the first width portion W1 and the second width portion W2 (L1 and L3 And has a first width W1 and a third width W3 having a smaller width than the second width W2 on the second width W2 side (L2). The effects of the first gas outlet 236 shown in FIG. 4 will be described in detail later.

A carbon dioxide gas laser can be used to process the cylindrical portion 209 and the reaction tube 203. That is, the gas supply slit 235, the first gas exhaust port 236, and the second gas exhaust port 237 provided in the cylindrical portion 209 are openings (holes) in the quartz pipe using numerical control carbon dioxide gas laser processing machine Form The cut surface of the opening (hole) of the gas supply slit 235, the first gas exhaust port 236, and the second gas exhaust port 237 is preferably formed by a straight line, a circular arc, or a combination of a straight line and a circular arc. In this case, since the program input to the numerically controlled carbon dioxide gas laser processing machine is relatively easy as compared with the complicated curve processing, it is possible to reduce the cost of forming the opening to the quartz tube.

As shown in FIG. 5, the gas supply slits 235 are formed so as to be respectively disposed between adjacent wafers 200 placed on a plurality of stages of the boat 217 housed in the processing chamber 201. It is done. In FIG. 5, the boat 217 is omitted. The gas supply slit 235 is preferably provided between the lowermost wafer 200 mountable on the boat 217 and the bottom plate of the boat 217 adjacent to the lower side, the uppermost wafer 200 and the boat adjacent to the upper side thereof. It is preferable that each of the wafers 200 be formed so as to face each other between the wafers 200 and between the wafers 200 and the top plate until it reaches the top plate of 217.

The gas supply holes 234a to 234c of the nozzles 340a to 340c may be formed at the central portion of the vertical width of each gas supply slit 235 so as to correspond to each of the gas supply slits 235 one by one. For example, when 25 gas supply slits 235 are formed, 25 gas supply holes 234a to 234c may be formed. That is, it is preferable that the number of the gas supply slit 235 and the gas supply holes 234a to 234c be formed by one plus the number of the wafers 200 to be mounted. With such a slit configuration, a flow of processing gas parallel to the wafer 200 can be formed on the wafer 200 (see the arrow in FIG. 5).

Further, the upper end (ceiling) of the nozzle disposition chamber 222 can be formed to have substantially the same height as the upper end of the cylindrical portion 209.

As shown in FIG. 6, the controller 280, which is a control unit (control means), is configured as a computer including a central processing unit (CPU) 121a, a random access memory (RAM) 121b, a storage device 121c, and an I / O port 121d. It is done. The RAM 121b, the storage device 121c, and the I / O port 121d are configured to be able to exchange data with the CPU 121a via the internal bus 121e. An input / output device 122 configured as, for example, a touch panel or the like is connected to the controller 280.

The storage device 121 c is configured by, for example, a flash memory, a hard disk drive (HDD), or the like. In the storage device 121c, a control program for controlling the operation of the substrate processing apparatus, and a process recipe in which a procedure, conditions and the like of the substrate processing described later are stored are readably stored. The process recipe is a combination of processes so as to cause the controller 280 to execute each procedure in the substrate processing process described later and obtain a predetermined result, and functions as a program. Hereinafter, the process recipe, the control program and the like are collectively referred to simply as a program. When the term "program" is used in the present specification, when only a process recipe alone is included, when only a control program alone is included, or both of them may be included. The RAM 121 b is configured as a memory area (work area) in which programs and data read by the CPU 121 a are temporarily stored.

The I / O port 121d is connected to the MFCs 320a to 321b, the valves 330a to 331b, the pressure sensor 245, the APC valve 244, the vacuum pump 246, the heater 207, the temperature sensor, the boat rotation mechanism 267, the boat elevator 115, etc. .

The CPU 121a is configured to read out and execute a control program from the storage device 121c, and to read out a process recipe from the storage device 121c in response to an input of an operation command from the input / output device 122 or the like. The CPU 121a adjusts the flow rates of various gases by the MFCs 320a to 321b, opens and closes the valves 330a to 331b, opens and closes the APC valve 244, and pressure from the APC valve 244 based on the pressure sensor 245 in accordance with the read process recipe. Adjustment operation, start and stop of vacuum pump 246, temperature adjustment operation of heater 207 based on temperature sensor, rotation and rotation speed adjustment of boat 217 by boat rotation mechanism 267, elevation operation of boat 217 by boat elevator 115, etc. are controlled. Is configured as.

The controller 280 is not limited to being configured as a dedicated computer, and may be configured as a general-purpose computer. For example, an external storage device (for example, a magnetic disk such as a hard disk, an optical disk such as a CD, an optical magnetic disk such as an MO, a semiconductor memory such as a USB memory) 123 storing the above-mentioned program is prepared. The controller 280 of the present embodiment can be configured by installing a program on a general-purpose computer and using the same. However, the means for supplying the program to the computer is not limited to the case of supplying via the external storage device 123. For example, the program may be supplied using communication means such as the Internet or a dedicated line without using the external storage device 123. The storage device 121 c and the external storage device 123 are configured as computer readable recording media. Hereinafter, these are collectively referred to simply as recording media. When the term "recording medium" is used in the present specification, when only the storage device 121c is included, only the external storage device 123 may be included, or both of them may be included.

Next, an outline of the operation of the substrate processing apparatus according to the present embodiment will be described. Here, a sequence example in which a SiN film is formed on a wafer 200 as a substrate will be described as one step of a manufacturing process of a semiconductor device using the above-described substrate processing apparatus. The operation of each part constituting the substrate processing apparatus is controlled by the controller 280.

The boat 217 on which a predetermined number of wafers 200 are placed is inserted into the reaction tube 203, and the reaction tube 203 is airtightly closed by the seal cap 219. In the air-tightly sealed reaction tube 203, the wafer 200 is heated, a process gas is supplied into the reaction tube 203, and the wafer 200 is subjected to heat treatment such as heating.

As the heat treatment, for example, NH ₃ gas as the first process gas, HCDS gas as the second process gas, and N ₂ gas as the third process gas are alternately supplied (HCDS gas supply → N ₂ purge → NH ₃ gas supply A SiN film is formed on the wafer 200 by repeating this cycle a predetermined number of times with one cycle of N ₂ purge. The processing conditions are, for example, as follows:
Temperature of wafer 200: 100 to 600 ° C.
Processing chamber pressure: 1 to 3000 Pa
HCDS gas supply flow rate: 1 to 2000 sccm
NH ₃ gas supply flow rate: 100 to 10000 sccm
N ₂ gas supply flow rate: 10 to 10000 sccm
Film thickness of SiN film: 0.2 to 10 nm.
First, NH ₃ gas is supplied from the gas supply pipe 310 a of the first processing gas supply system into the processing chamber 201 through the gas supply holes 234 a of the nozzle 340 a and the gas supply slit 235. Specifically, by opening the

valves

330a and 331a, supply of the NH ₃ gas from the gas supply pipe 310a into the processing chamber 201 is started together with the carrier gas. At this time, the opening degree of the APC valve 244 is adjusted to maintain the pressure in the processing chamber 201 at a predetermined pressure. After the predetermined time has elapsed, the valve 330a is closed to stop the supply of the NH ₃ gas.

The NH ₃ gas supplied into the processing chamber 201 is supplied to the wafer 200, flows in parallel on the wafer 200, and then flows from the top to the bottom in the gap S through the first gas exhaust port 236. The gas is exhausted from the exhaust pipe 231 via the gas exhaust port 237 and the exhaust outlet 230.

When the valve 331 b and the

valves

330 c and 331 d of the inert gas supply pipe connected to the gas supply pipe 310 b are opened and the inert gas such as N ₂ flows while the NH ₃ gas is supplied into the processing chamber 201, It is possible to prevent the NH ₃ gas from flowing into the

gas supply pipes

310b, 310c, and 311d.

After the valve 330 a is closed and the supply of NH ₃ gas into the processing chamber 201 is stopped, the inside of the processing chamber 201 is exhausted to remove the NH ₃ gas and reaction products remaining in the processing chamber 201. . At this time, when inert gas such as N _{2 is} supplied from the

gas supply pipes

310a, 310b, 310c, and 311d to the inside of the processing chamber 201 and in the gap S and purged, residual gas in the processing chamber 201 and the gap S is eliminated. Effect can be further enhanced.

Next, the HCDS gas is supplied from the gas supply pipe 310 b of the second processing gas supply system into the processing chamber 201 through the gas supply holes 234 b of the nozzle 340 b and the gas supply slit 235. Specifically, the

valves

330 b and 331 b are opened to start supply of the HCDS gas from the gas supply pipe 310 b into the processing chamber 201 together with the carrier gas. At this time, the opening degree of the APC valve 244 is adjusted to maintain the pressure in the processing chamber 201 at a predetermined pressure. After the predetermined time has elapsed, the valve 330 b is closed to stop the supply of the HCDS gas.

The HCDS gas supplied into the processing chamber 201 is supplied to the wafer 200, flows in parallel over the wafer 200, and then flows from the top to the bottom through the gap S through the first gas exhaust port 236, and the second gas The exhaust gas is exhausted from the exhaust pipe 231 via the exhaust port 237 and the exhaust outlet 230.

While HCDS gas is supplied into the processing chamber 201, the valve 331a of the inert gas supply pipe connected to the gas supply pipe 310a and the

valves

330c and 331d of the

gas supply pipes

310c and 311d are opened to make a small amount of N ₂ etc. When the inert gas flows, the HCDS gas can be prevented from entering the

gas supply pipes

310a, 310c, and 311d by diffusion, and by flowing a larger amount of the inert gas, the wafer inner film thickness uniformity can be obtained. It can also be controlled.

After the valve 330 b is closed and the supply of the HCDS gas into the processing chamber 201 is stopped, the inside of the processing chamber 201 is exhausted to remove the HCDS gas, the reaction product and the like remaining in the processing chamber 201. At this time, when inert gas such as N _{2 is} supplied from the

gas supply pipes

When the processing of the wafer 200 is completed, the boat 217 is unloaded from the reaction tube 203 in the reverse procedure of the above-described operation. The wafer 200 is transferred from the boat 217 to the pod of the transfer rack by a wafer transfer machine (not shown), and the pod is transferred from the transfer rack to the pod stage by the pod transfer machine, and is transferred by the external transfer device. It is carried out of the body.

In the above embodiment, although the case where the first process gas and the second process gas are alternately supplied has been described, the present invention is also applied to the case where the first process gas and the second process gas are simultaneously supplied. be able to. The nozzle arrangement chamber 222 is not limited to being divided into three spaces, and may be divided into two or four or more spaces. The number of spaces to be partitioned can be appropriately changed according to the number of nozzles required for the desired heat treatment.

Also, the shape of the nozzles may be changed. For example, the gas supply holes 234a provided in the nozzle 340b used for supplying the processing gas having a low decomposition temperature may be formed in an elongated slit which continuously opens over a plurality of wafers, or a cooling gas is provided around the periphery It is good as a double pipe structure which made

As described above, the first gas exhaust port 236 for exhausting the gas evenly from the wafer placement area is not limited to the film formation on the wafer 200, but may be a gas cleaning or precoating for the surface of the cylindrical portion 209 or the reaction tube 203. Works well. That is, while the cleaning time is set so that the most difficult to remove or the thickest part of the film to be removed can be removed, the unevenness of the cleaning and precoating can be reduced, so that they can be performed in a short time. Also, the life of the reaction tube 203 can be extended.

(Relationship between the shape of the first gas exhaust port 236 and the flow of the processing gas)
FIG. 7 is a conceptual diagram for explaining the details of the flow of processing gas in the reaction tube at the first gas exhaust port 236 described with reference to FIG. FIG. 7A shows the shape of the first gas exhaust port 236 described in FIG. 4 when the reaction pipe (outer pipe) 203 and the cylindrical portion (inner pipe) 209 are viewed from the direction of the exhaust outlet 230. It is a front view showing. FIG. 7B is a side view conceptually showing the flow of processing gas when the reaction tube (outer tube) 203 and the cylindrical portion (inner tube) 209 shown in FIG. 7A are viewed from the side. . 7B shows a boat 217 on which a plurality of wafers 200 are stacked in multiple stages, a boat support base 218 supporting the boat 217, and a nozzle arrangement chamber 222 in which the nozzles 340a to 340d are provided. ing. However, in FIG. 7B, the description of the nozzles 340a to 340d and the plurality of gas supply slits 235 provided on the side surface of the cylindrical portion (inner pipe) 209 is omitted. Further, the first gas exhaust port 236 in FIG. 7 (b) is once narrowed from the maximum width W1 toward the exhaust outlet 230 as the minimum width W3 as the throttle shape, and again, the minimum width W3 at the exhaust outlet 230 side It conceptually shows the shape expanded to a wider predetermined width W2.

The first gas exhaust port 236 shown in FIG. 7A has a portion of the maximum width W1, a portion of the minimum width W3, and a portion of the predetermined width W2 wider than the minimum width W3, as described in FIG. And. That is, the width in the horizontal direction of the first gas exhaust port 236 from the maximum width W1 toward the exhaust outlet 230 side is once made as the minimum width W3 as the throttle shape, and again from the minimum width W3 on the exhaust outlet 230 side It is expanded to a wide predetermined width W2. With this configuration, as indicated by arrows in FIG. 7B, the flow of the processing gas supplied from the plurality of gas supply slits 235 can be substantially uniformed among the wafers 200 stacked in multiple stages. .

The generation of the flow of the processing gas flowing into the gap other than the wafer processing space 210 is suppressed in the portion near the exhaust outlet 230, and the reduction of the flow rate of the processing gas on the wafer in the portion near the exhaust outlet 230 is prevented. Thereby, the flow of the processing gas between the wafers 200 stacked in multiple stages can be made uniform.

That is, at the lower end portion of the first gas exhaust port 236 where the processing gas that has entered the outer periphery of the wafer 200 converges, the width of the first gas exhaust port 236 is wider than the minimum width W3 and the predetermined width W2 is wider than the minimum width W3. By doing this, it is possible to suppress a decrease in the flow rate of the processing gas of the portion of the wafer 200 corresponding to the lower end portion of the first gas exhaust port 236. Thereby, the flow of the processing gas between the wafers 200 stacked in multiple stages can be made uniform.

FIG. 8 is a conceptual diagram for explaining the flow of gas in the reaction tube at the first gas exhaust port 236P1 according to Comparative Example 1. As shown in FIG. FIG. 8A is a front view showing the shape of the first gas exhaust port 236P1 when the reaction pipe (outer pipe) 203 and the cylindrical portion (inner pipe) 209 are viewed from the direction of the exhaust outlet 230. FIG. 8 (b) is a side view conceptually showing the flow of the processing gas when the reaction tube (outer tube) 203 and the cylindrical portion (inner tube) 209 shown in FIG. 8 (a) are viewed from the side. . FIG. 8B shows a boat 217 on which a plurality of wafers 200 are stacked in multiple stages, a boat support base 218 supporting the boat 217, and a nozzle arrangement chamber 222 in which the nozzles 340a to 340d are provided. . However, in FIG. 8B, the description of the nozzles 340a to 340d and the plurality of gas supply slits 235 provided on the side surface of the cylindrical portion (inner pipe) 209 is omitted. The first gas exhaust port 236P1 in FIG. 8B conceptually shows that the width W1P1 in the horizontal direction of the first gas exhaust port 236P1 is substantially uniform in the vertical direction.

As shown in FIG. 8A, the first gas exhaust port 236P1 of Comparative Example 1 has a substantially uniform width in the vertical direction of the cylindrical portion (inner pipe) 209 on the side surface of the cylindrical portion (inner pipe) 209. It is a configuration having W1P1. In this case, as shown by an arrow in FIG. 8B, when the exhaust outlet 230 is provided only on the lower side (or upper side) of the vertical reaction tube (outer tube) 203 and the cylindrical portion (inner tube) 209, Between the wafers 200 stacked in multiple stages, the flow of the processing gas supplied from the plurality of gas supply slits 235 tends to flow toward the exhaust outlet 230, so the flow among the wafers 200 becomes uneven.

FIG. 9 is a conceptual diagram for explaining the flow of gas in the reaction tube at the first gas exhaust port 236P2 according to Comparative Example 2. As shown in FIG. FIG. 9A is a front view showing the shape of the first gas exhaust port 236P2 when the reaction pipe (outer pipe) 203 and the cylindrical portion (inner pipe) 209 are viewed from the direction of the exhaust outlet 230. FIG. FIG. 9B is a side view conceptually showing the flow of gas in the reaction tube when the reaction tube (outer tube) 203 and the cylindrical portion (inner tube) 209 shown in FIG. 9A are viewed from the side. FIG. FIG. 9B illustrates a boat 217 on which a plurality of wafers 200 are stacked in multiple stages, a boat support base 218 supporting the boat 217, and a nozzle arrangement chamber 222 in which the nozzles 340a to 340d are provided. . However, in FIG. 9B, the description of the nozzles 340a to 340d and the plurality of gas supply slits 235 provided on the side surface of the cylindrical portion (inner pipe) 209 is omitted. Further, the first gas exhaust port 236P2 in FIG. 9B conceptually shows that the horizontal width of the first gas exhaust port 236P2 is gradually narrowed in the vertical direction from the maximum width W1P2 to the minimum width W2P2. It shows.

As shown in FIG. 9A, in the first gas exhaust port 236P2 of Comparative Example 2, the side surface of the cylindrical portion (inner pipe) 209 corresponds to the vertical direction of the cylindrical portion (inner pipe) 209 (from the top to the bottom) ), The maximum width W1P2 is gradually narrowed to the minimum width W2P2. The first gas exhaust port 236P2 of the second comparative example is directed to the first gas exhaust port 236P2 toward the exhaust port 230 in order to suppress the inclination of the flow concentrated to the exhaust port 230 as described in FIG. 8B. The width in the horizontal direction of the lens is a stop shape. In this case, as indicated by an arrow in FIG. 9B, the flow in a certain range away from the side of the exhaust outlet 230 becomes uniform. However, at a position near the exhaust outlet 230, a flow of processing gas flowing into a gap other than the wafer processing space 210 is generated (see arrow A0). Therefore, the flow rate of the processing gas on the wafer near the exhaust outlet 230 decreases. That is, when the flow of the processing gas into the area other than the wafer processing space 210 occurs, the flow of the processing gas between the wafers stacked in multiple stages becomes uneven.

(Positional relationship between the first gas exhaust port 236 and the exhaust outlet 230)
FIG. 10 is a schematic view for explaining the flow of the processing gas to the exhaust outlet 230 in comparison. Fig.10 (a) is the figure which looked at the reaction tube 203 which concerns on embodiment, and FIG.10 (b) the reaction tube which concerns on a comparative example from upper direction. The shape of the first gas exhaust port 236 of the reaction pipe of FIG. 10B is the same as that of the reaction pipe 203 according to the embodiment, but the positional relationship between the first gas exhaust port 236 and the exhaust outlet 230 is different. That is, the reaction tube of the comparative example is disposed at a position where the exhaust outlet 230 provided in the reaction tube (outer tube) 203 and the first gas exhaust port 236 provided in the cylindrical portion (inner tube) 209 face each other. It is placed at an offset position by an angle of 90 degrees. For this reason, the conductance between the first gas exhaust port 236 and the exhaust outlet 230 is reduced. Further, as indicated by arrows in FIG. 10B, the flow of the processing gas on the surface of the wafer 200 is uneven, and the flow velocity unevenness of the processing gas in the surface of the wafer 200 is easily generated.

On the other hand, in the reaction tube 203 of the embodiment, as shown in FIGS. 4 and 7, the positional relationship between the first gas exhaust port 236 and the exhaust outlet 230 is viewed from the central axis CA of the cylindrical portion 209. In the same direction. In other words, when the reaction tube (outer tube) 203 and the cylindrical portion (inner tube) 209 are viewed from above, the formation region 235a of the gas supply slit 235, the first gas exhaust port 236, and the exhaust outlet 230 It is arranged substantially in a row or straight. The formation region 235 a of the gas supply slit 235 is provided at a position facing or substantially directly facing the first gas exhaust port 236. Further, the formation region 235 a of the gas supply slit 235 is provided on the wall of the cylindrical portion 209 opposite to the first gas exhaust port 236 when viewed from the central axis CA of the cylindrical portion 209.

Thereby, as shown by the arrow in FIG. 10B, the flow of the processing gas on the wafer 200 can be made substantially uniform, and the occurrence of the flow velocity unevenness of the processing gas in the surface of the wafer 200 is suppressed.

(Relationship between the position of the first gas exhaust port 236 and the wafer 200)
FIG. 11 is a view for explaining the relationship between the opening position of the first gas exhaust port 236 and the wafer 200 according to the embodiment. Fig.11 (a) is a side view at the time of seeing reaction tube (outer tube) 203 and cylinder part (inner tube) 209 which are shown by Fig.7 (a) from the side surface similarly to FIG.7 (b). . 11 (b) is an enlarged view of a portion XII (a) of FIG. 11 (a), and FIG. 11 (c) is an enlarged view of a portion XII (b) of FIG. 11 (a). 11 (a), (b) and (c), the shape of the first gas exhaust port 236 is the same as the shape of the first gas exhaust port 236 shown in FIGS. 4 and 7 (a). The first gas exhaust port 236 in FIGS. 11A, 11B, and 11C schematically shows its shape, as in FIG. 7B. In FIG. 11A, a boat 217 on which a plurality of wafers 200 are stacked in multiple stages, a boat support base 218 supporting the boat 217, and a nozzle disposition chamber 222 provided with nozzles 340a to 340d are depicted ing. However, in FIG. 11A, the description of the nozzles 340a to 340d and the plurality of gas supply slits 235 provided on the side surface of the cylindrical portion (inner pipe) 209 is omitted.

As shown in FIG. 11A, in the boat 217, the tubes of the reaction tube 203 are held in a horizontal posture while the plurality of wafers 200 are spaced at a constant distance (p) from each other and aligned with each other. It is loaded in multiple stages in the axial direction. 236U indicates the upper end of the opening of the first gas exhaust port 236 in the cylindrical portion (inner pipe) 209, and 236L indicates the lower end of the opening of the first gas exhaust port 236 in the cylindrical portion (inner pipe) 209 There is. In FIG. 11 (a), a square dotted line XII (b) is a portion surrounding the four wafers 200 in the upper part of the boat 217 and the upper part of the first gas exhaust port 236, and FIG. A diagram is shown. Further, in FIG. 11A, a square dotted line XII (c) is a portion surrounding the lower part of the four wafers 200 in the boat 217 and the lower portion of the first gas exhaust port 236, as shown in FIG. The enlarged view is shown.

As shown in FIG. 11B, the first gas exhaust port 236 at the uppermost wafer 200 and the cylindrical portion (inner pipe) 209 of the wafers 200 loaded on the boat 217 at a constant interval (pitch) p. The distance X is longer than half (p / 2) of the pitch p of the wafers 200 on the basis of the pitch p between the wafers 200 and twice the pitch p of the wafers 200 (the distance X is a distance X with the upper end 236U of It is preferable to set the value shorter than 2p) (p / 2 <X <2p). Therefore, the upper end 236U of the first gas exhaust port 236 is set at a position higher by p / 2 to 2p than the position of the wafer 200 placed on the top.

In addition, as shown in FIG. 11C, in the wafers 200 loaded on the boat 217 at a constant interval (pitch) p, the first gas exhaust in the lowermost wafer 200 and the cylindrical portion (inner pipe) 209 Assuming that the distance between the lower end 236L of the opening 236 and the lower end 236L is a distance Y, the distance Y is longer than half (p / 2) of the pitch p of the wafers 200 based on the inter-wafer pitch p. It is preferable to set a value (p / 2 <Y <2p) shorter than double (2p). Therefore, the lower end 236L of the first gas exhaust port 236 is set at a position p / 2 to 2p lower than the position of the wafer 200 placed at the lowermost part.

For example, assuming that the interval (pitch) p of loading of the wafers 200 is, for example, 10 mm (millimeter), the distance X or the distance Y is about 5 to 20 mm. In this manner, the upper end 235U and the lower end 235L of the first gas exhaust port 236 are offset by about 5 to 20 mm from the positions of the top wafer and the bottom wafer of the loaded wafers 200, Preferably, the first gas exhaust port 236 is opened in the pipe 209. The opening of the first gas exhaust port 236 to the cylindrical portion (inner pipe) 209 may be performed by a numerically controlled carbon dioxide gas laser processing machine.

Thus, the uppermost wafer to the lowermost wafer of the loaded wafers 200 are arranged in the range from the upper end 235U to the lower end 235L of the first gas exhaust port 236, so that the entire upper and lower areas of the loaded wafers 200 are obtained. Thus, the first gas exhaust port 236 enables the process gas to be efficiently exhausted.

(Modified example of the first gas exhaust port)
Hereafter, the modification of the 1st gas exhaust port 236 is demonstrated using FIGS. 12-18.

(Modification 1)
FIG. 12 is a view showing the shape of the first gas exhaust port 236A according to the first modification. The configuration other than the shape of the first gas exhaust port 236A is the same as the configuration shown in FIG. 4, and the description thereof will be omitted.

The first gas exhaust port 236A is provided along the vertical direction (Y direction) between the line Y1 and the line Y5, and is configured by a single opening whose width changes continuously. The first gas exhaust port 236A has a substantially inverted triangular shape between the line Y1 and the line Y2, and has a circular or arc-shaped opening 236A1 between the line Y2 and the line Y5. The contour of the first gas exhaust port 236A is configured by a combination of one or more straight lines and a circular arc.

The first gas exhaust port 236A has the maximum width W1 in the line Y1, and the width is gradually narrowed from the maximum width W1 between the line Y1 and the line Y2b to be the minimum width W3. The width W3 of the first gas exhaust port 236A is substantially constant between the line Y2b and the line Y2, and the first gas exhaust port 236A is widened from the minimum width W3 to the predetermined width W2 between the line Y2 and the line Y3. The first gas exhaust port 236A is gradually narrowed from the predetermined width W2 between the line Y3 and the line Y5.

That is, the first gas exhaust port 236A has the maximum width W1 in the line Y1, and has the minimum width W3 between the line Y2b and the line Y2. The width of the first gas exhaust port 236A is gradually widened from the minimum width W3 to a predetermined width W2 wider than the minimum width (W3) between the line Y2 and the line Y3. The width of the first gas exhaust port 236A is gradually narrowed from the predetermined width W2 from the line Y3 to the line Y5.

Also in the first gas exhaust port 236A of such a shape, it is possible to obtain the same effect as the first gas exhaust port 236 shown in FIG. 4.

(Modification 2)
FIG. 13 is a view showing the shape of the first gas exhaust port 236B according to the second modification. The configuration other than the shape of the first gas exhaust port 236B is the same as the configuration shown in FIG. 4, and the description thereof will be omitted.

The first gas exhaust port 236B has a first slit 236B1 having a substantially inverted triangle shape provided from the line Y1 to the line Y3 and a width W4 provided on the left and right of the first slit 236B1 in the line Y2 to the line Y3. And a third slit 256B3 having a rectangular shape with a width W4. The contour of the first gas exhaust port 236B is configured by a combination of one or more straight lines.

The first slit 236B1 has the maximum width W1 in the line Y1, and the width is gradually narrowed from the maximum width W1 in the line Y1 to the line Y2b to be the minimum width W3. The width W3 of the first slit 236B1 is substantially constant between the line Y2b and the line Y3. The substantial predetermined width W2 of the first gas exhaust port 236B is a value obtained by adding the minimum width W3 and twice the width W4 by the second and third slits 236B2 and 236B3 in the line Y2 to the line Y3 (W2 = W3 + 2 W4). The predetermined width W2 is configured by forming a plurality of openings (openings of a width W4 of the first slit 236B1, openings of the second and third slits 236B2 and 236B3) along the circumferential direction of the inner pipe 209. There is.

That is, the first gas exhaust port 236B shown in FIG. 13 has the maximum width W1 in the line Y1, and has the minimum width W3 between the line Y2b and the line Y2. The width of the first gas exhaust port 236B is widened from the minimum width W3 to a predetermined width W2 (W3 + 2W4) wider than the minimum width (W3) from the line Y2 to the line Y3.

Also in the first gas exhaust port 236B of such a shape, it is possible to obtain the same effect as the first gas exhaust port 236 shown in FIG. 4.

(Modification 3)
FIG. 14 is a view showing the shape of the first gas exhaust port 236C according to the third modification. The configuration other than the shape of the first gas exhaust port 236C is the same as the configuration shown in FIG. 4, and the description thereof will be omitted.

The first gas exhaust port 236C is provided from the line Y1 to the line Y5, and has a width (diameter) W5 provided to the left and right of the first slit 236C1 at the substantially inverted triangle shaped first slit 236C1 and the line Y2 to the line Y5. And a circular second slit 256C3 having a width (diameter) W5. The contour of the first gas exhaust port 236C is configured by a combination of one or more straight lines and a circular arc.

The first slit 236C1 has a maximum width W1 at the line Y1, and the width is gradually narrowed from the line Y1 to the line Y5. The first gas exhaust port 236C has a minimum width W3 at the line Y2. The width of the first gas exhaust port 236C is gradually widened from the minimum width W3 from the line Y2 to the line Y3 by the second and third slits 236C2 and 236C2, and the line Y3 has a predetermined width W2 wider than the minimum width W3 and Become. The predetermined width W2 is a value (W2 = (W6 + 2W5)> W3, W6 <W3) obtained by adding the width W6 equal to or less than the minimum width W3 and a value twice the width W5. The predetermined width W2 is configured by forming a plurality of openings (openings of width W6 of the first slit 236C1, openings of the second and third slits 236C2, 236C3) along the circumferential direction of the inner pipe 209 There is.

That is, the first gas exhaust port 236C shown in FIG. 14 has the maximum width W1 in the line Y1 and the minimum width W3 in the line Y2. The width of the first gas exhaust port 236C is widened from the minimum width W3 to the predetermined width W2 (W2 = W6 + 2W4, W6 <W3) wider than the minimum width W3 at the line Y3.

Also in the first gas exhaust port 236C of such a shape, it is possible to obtain the same effect as the first gas exhaust port 236 shown in FIG. 4.

(Modification 4)
FIG. 15 is a view showing the shape of the first gas exhaust port 236D according to the fourth modification. The configuration other than the shape of the first gas exhaust port 236D is the same as the configuration shown in FIG. 4, and the description thereof will be omitted.

The first gas exhaust port 236D is configured by combining a plurality of slits SL1 having a width W7. The plurality of slits SL1 are formed in the wall of the inner tube 209 by being divided into a plurality of slits SL1 so as to be opened corresponding to a plurality of positions where the wafer 200 is placed in the inner tube 209 in the central axis CA direction. . The outline of each of the slits SL1 is formed in a rectangular shape that is long in the circumferential direction of the inner pipe 209.

The first gas exhaust port 236D has three slits SL1 of width W7 arranged along the horizontal direction (X direction) between the line Y1 and the line Y2b in a plurality of stages (in the Y direction). In the example, five stages are provided. The first gas exhaust port 236D has a configuration in which one slit SL1 having a width W7 is provided in a plurality of stages (10 stages in this example) in the vertical direction between the line Y2b and the line Y2. The first gas exhaust port 236D has a configuration in which three slits SL1 of width W7 are provided in a plurality of stages (two stages in this example) in the vertical direction (Y direction) between the line Y2 and the line Y3. There is. The contour of the first gas exhaust port 236D is configured by a combination of one or more straight lines.

That is, the first gas exhaust port 236D shown in FIG. 15 has the maximum width W1 (W1 = 3W7) between the line Y1 and the line Y2b, and the minimum width W3 (W3) between the line Y2b and the line Y2. It has = W7). The width of the first gas exhaust port 236D is widened from the minimum width W3 to a predetermined width W2 (W2 = 3 W7) wider than the minimum width (W3) between the line Y2 and the line Y3. The maximum width W1 is configured to form a plurality of openings (openings of the three slits SL1) along the circumferential direction of the inner pipe 209. The predetermined width W2 is formed by forming a plurality of openings (openings of the three slits SL1) along the circumferential direction of the inner pipe 209.

Also in the first gas exhaust port 236D having such a shape, it is possible to obtain the same effect as the first gas exhaust port 236 shown in FIG.

(Modification 5)
FIG. 16 is a view showing the shape of the first gas exhaust port 236E according to the fifth modification. The configuration other than the shape of the first gas exhaust port 236E is the same as the configuration shown in FIG. 4, and the description thereof will be omitted.

The first gas exhaust port 236E has a configuration in which a first slit SL1 of width Wa and a second slit SL2 of width Wb are combined. The heights of the first and second slits SL1 and SL2 are assumed to be the same. The first slit SL1 and the second slit SL2 are divided into a plurality of openings in the direction of the central axis CA corresponding to a plurality of positions at which the wafer 200 is mounted in the inner pipe 209. Formed on the wall of The outline of each of the first slit SL1 and the second slit SL2 is formed in a rectangular shape that is long in the circumferential direction of the inner pipe 209.

The first gas exhaust port 236E is provided between the two first slits SL1 and the two first slits SL1 aligned along the horizontal direction (X direction) between the line Y1 and the line Y2b. A plurality of steps (five steps in this example) are provided in the vertical direction (Y direction) with the second slits SL2. The first gas exhaust port 236E has two first slits SL1 arranged along the horizontal direction (X direction) between the line Y2b and the line Y2 in a plurality of stages (Y direction) in the vertical direction (Y direction). In this example, 10 stages are provided. In this example, the second slit SL2 provided between the line Y1 and the line Y2b is removed from between the two first slits S11 between the line Y2b and the line Y2. The first gas exhaust port 236E is provided between two first slits SL1 and two first slits SL1 arranged along the horizontal direction (X direction) between the line Y2 and the line Y3. A plurality of steps (two steps in this example) are provided in the vertical direction (Y direction) with the second slit SL2. The contour of the first gas exhaust port 236E is configured by a combination of one or more straight lines.

That is, the first gas exhaust port 236E shown in FIG. 16 has the maximum width W1 (W1 = 2Wa + Wb) between the line Y1 and the line Y2b, and the minimum width W3 (W3) between the line Y2b and the line Y2. It has 2 = 2Wa). The width of the first gas exhaust port 236E is widened from the minimum width W3 (W3 = 2Wa) to a predetermined width W2 (W2 = 2Wa + Wb) wider than the minimum width (W3) between the line Y2 and the line Y3. The maximum width W1 is configured to form a plurality of openings (an opening of the two first slits SL1 and an opening of one second slit SL2) along the circumferential direction of the inner pipe 209. Further, the predetermined width W2 is configured by forming a plurality of openings (an opening of the two first slits SL1 and an opening of the one second slit SL2) along the circumferential direction of the inner pipe 209.

Also in the first gas exhaust port 236E having such a shape, it is possible to obtain the same effect as the first gas exhaust port 236 shown in FIG. 4.

(Modification 6)
FIG. 17 is a view showing the shape of the first gas exhaust port 236F according to the sixth modification. The configuration other than the shape of the first gas exhaust port 236F is the same as the configuration shown in FIG. 4, and the description thereof will be omitted.

The first gas exhaust port 236E has a rectangular first slit 236F1 of width W8, rectangular second and third slits 236F2 and 236F3 of width W8, and a fourth rectangular slit 236F4 and fifth of width W9. It is the structure which combined slit 236F5.

The first slit 236F1 is provided between the line Y1 and the line Y3 along the vertical direction (Y direction). The second slit 236F2 and the third slit 236F3 are provided along the vertical direction so as to sandwich the first slit F1 between the line Y1 and the line Y2a. The fourth slit 236F4 and the fifth slit 236F5 are provided along the vertical direction so as to sandwich the first slit F1 between the line Y2 and the line Y3. The outline of the first gas exhaust port 236F is configured by a combination of one or more straight lines.

That is, the first gas exhaust port 236F shown in FIG. 17 has the maximum width W1 (W1 = 3W8) between the line Y1 and the line Y2b, and the minimum width W3 (W3) between the line Y2b and the line Y2. It has = W8). The width of the first gas exhaust port 236F is widened from the minimum width W3 (W3 = W8) to a predetermined width W2 (W2 = W3 + 2W9) wider than the minimum width (W3) between the line Y2 and the line Y3. The maximum width W1 is configured to form a plurality of openings (an opening of the first slit 236F1, an opening of the second slit 236F2, and an opening of the third slit 236F3) along the circumferential direction of the inner tube 209 There is. Further, the predetermined width W2 is configured by forming a plurality of openings (the opening of the first slit 236F1, the opening of the fourth slit 236F4, and the opening of the fifth slit 236F5) along the circumferential direction of the inner pipe 209. .

(Modification 7)
FIG. 18 is a view showing the shape of the first gas exhaust port 236G according to the seventh modification. The configuration other than the shape of the first gas exhaust port 236G is the same as the configuration shown in FIG. 4, and the description thereof will be omitted.

The first gas exhaust port 236G is configured by forming the first gas exhaust port 236 of FIG. 4 with a plurality of slits. In this example, the first gas exhaust port 236G is configured by the first to fifth slits SL1 to SL5 having different widths. The heights of the first to fifth slits SL1 to SL5 are assumed to be the same. The first slit SL1 has a width Wc, the second slit SL2 has a width Wd, the third slit SL3 has a width We, the fourth slit SL4 has a width Wf, and the fifth slit SL5 has a width Wg. It is assumed that the widths (Wc, Wd, We, Wf, Wg) have a relationship of Wc> Wd> We> Wg> Wf. The first to fifth slits SL1 to SL5 are divided into a plurality of openings in the direction of the central axis CA corresponding to a plurality of positions at which the wafer 200 is mounted in the inner pipe 209. Formed on the wall. The contour of each of the first to fifth slits SL1 to SL5 is formed in a rectangular shape that is long in the circumferential direction of the inner pipe 209.

The first gas exhaust port 236G is arranged in the vertical direction (Y direction) between the line Y1 and the line Y2a, and in this example, from the first stage slit to the eighteenth stage slit.

Each of the first and second stages of slits is composed of two first slits SL1 arranged in the horizontal direction (X direction). Each of the third and fourth slits is constituted by two second slits SL2 arranged in the horizontal direction (X direction). Each of the fifth to eighth slits is constituted by the first slit SL1. Each of the ninth to eleventh slits is formed of the third slit SL3. Each of the slits in the twelfth to sixteenth stages is constituted by the fourth slit SL4. The seventeenth slit is constituted by the fourth slit SL4. The eighteenth slit is constituted by the third slit SL3. The contour of the first gas exhaust port 236G is configured by a combination of one or more straight lines.

The width of the first gas exhaust port 236G at the line Y1 is the width 2Wc of the two first slits SL1, and has a maximum width W1. The width of the first gas exhaust port 236G is gradually narrowed from the width 2Wc to the width 2Wd of the two second slits SL2 and the width Wc of the first slit SL1 from the line Y1 to the line Y2a. The width of the first gas exhaust port 236G from the line Y2a to the line Y2 is the width Wf of the fourth slit SL4, and has a minimum width W3. The first gas exhaust port 236G is a third slit having a width from the minimum width W3 (Wf) to the width Wg of the fourth slit SL5 and a predetermined width W2 wider than the minimum width (W3) in the line Y2 to the line Y3 It is gradually widened to the width We of SL3. The maximum width W1 is configured to form a plurality of openings (openings of two first slits SL1) along the circumferential direction of the inner pipe 209. The predetermined width W2 is configured by forming the opening of the third slit SL3 along the circumferential direction of the inner pipe 209.

That is, the first gas exhaust port 236G shown in FIG. 18 has the maximum width W1 (2Wc) in the line Y1, and the minimum width W3 (Wf) in the line Y2a to the line Y2. The width of the first gas exhaust port 236F is widened from the minimum width W3 to a predetermined width W2 (We) wider than the minimum width (W3) at the line Y3.

Also in the first gas exhaust port 236G of such a shape, it is possible to obtain the same effect as the first gas exhaust port 236 shown in FIG. 4.

(Modification 8)
Hereafter, the modification of the reaction tube 203 is demonstrated using FIGS. 19-22.
FIG. 19 is a horizontal sectional view of the reaction tube viewed from above. An intermediate portion 203 b of the reaction tube (outer tube) 203 is substantially cylindrical, and a gap S is provided between the middle portion 203 b and the cylindrical portion (inner tube) 209. The inside of the cylindrical portion (inner pipe) 209 constitutes a processing chamber 201. The cylindrical portion (inner pipe) 209 is substantially cylindrical, and has, in a region near the exhaust outlet 230, four semicircular projections (bulges) 209a for installing an optional nozzle. A nozzle chamber 222 is provided between the cylindrical portion (inner tube) 209 and the intermediate portion 203 b of the reaction tube (outer tube) 203.

The nozzle chamber 222 is divided into three by a partition plate 248, and one nozzle can be arranged in each of the partitions. In order to insert the three nozzles (340a, 340b, 340c) into the three sections, an arc-shaped hole 203ch1 is provided in the region of the lower portion 203c of the reaction tube (outer tube) 203 corresponding to the nozzle chamber 222. The cylindrical portion (inner pipe) 209 is provided with a gas supply slit 235 for supplying the processing gas supplied from the three nozzles (340a, 340b, 340c) to the processing chamber 201. Further, an arc-shaped hole 203 ch 2 is provided in a region near the exhaust outlet 230 of the lower portion 203 c of the reaction tube (outer tube) 203 in order to improve the gas exhaust performance.

FIG. 20 is a bottom view of the reaction tube shown in FIG. 19 as viewed from below. The lower portion of the cylindrical portion (inner tube) 209 has an open substantially circular hole portion 209 h, and a plurality of wafers 200 loaded on the boat 217 can be inserted into the processing chamber 201 from the hole portion 209 h. It has become. An arc-shaped hole 203 ch 1 is provided in the region of the lower portion 203 c of the reaction tube (outer tube) 203 corresponding to the nozzle chamber 222. An arc-shaped hole 203 ch 2 is provided in a region near the exhaust outlet 230 of the lower portion 203 c of the reaction tube (outer tube) 203.

21 is a vertical sectional view of the reaction tube shown in FIG. 19 as viewed from the right side. Inside the reaction tube (outer tube) 203, a cylindrical portion (inner tube) 209 is provided. The cylindrical portion (inner pipe) 209 includes a side surface portion 209 b and a ceiling portion 209 c. The lower portion 203c of the reaction tube (outer tube) 203 and the lower portion of the side surface portion 209b of the cylindrical portion (inner tube) 209 are mutually coupled and integrated. The ceiling portion 209 c is formed of a substantially circular flat plate. The side surface portion 209 b has a substantially cylindrical shape. In the side surface portion 209 b, a plurality of gas supply slits 235 are provided on the side of the nozzle chamber 222 corresponding to the arrangement region of the plurality of stacked wafers 200. Further, in the side surface portion 209 b, the first gas exhaust port 236 is provided corresponding to the arrangement region of the plurality of stacked wafers 200 which is an upper portion of the exhaust outlet 230. Note that the gas supply slits 235 and the first gas exhaust ports 236 in multiple stages are provided at positions facing or substantially directly facing the side surface portion 209b.

The nozzle chamber 222 is divided by a cut 233 at a position slightly below the arrangement region of the plurality of stacked wafers 200. The division position corresponds to the boundary between the heating area (heating area) by the heater 207 of the reaction furnace and the non-heating area (nonuniform area), and division by the cut 233 suppresses tensile stress due to temperature difference ing. Since the width of the cut 233 is sufficiently small, the mixing of the gas thereby can be ignored.

In addition, a rectangular second gas exhaust port 237 serving as a purge gas exhaust port is provided at the lower portion of the side surface portion 209b. Three second gas exhaust ports 237 are provided in the circumferential direction of the side surface portion 209 b, and are provided for positively flowing the purge gas on the lower side of the processing chamber 201 to the exhaust port 230.

The lower end and the upper end of the first gas exhaust port 236 are disposed at substantially the same height in the Y direction as the lower end and the upper end of the gas supply slit 235 of the plurality of stages.

FIG. 22 is a vertical cross-sectional view of the reaction tube shown in FIG. 19 as viewed from the rear. A first gas exhaust port 236 is provided on the wall of the side surface portion 209 b of the cylindrical portion (inner pipe) 209 corresponding to the arrangement area of the wafer 200. The first gas outlet 236 is, in this example, the shape of the first gas outlet 236 described in FIG. 4. The first gas exhaust port 236 is formed in the wall of the side surface portion 209b corresponding to the first gas exhaust port forming region 236R shown by a rectangular dotted line. The first gas exhaust port 236 can have the shape of Modifications 1-7 shown in FIGS. 12-18.

The second gas exhaust port 237 is provided on the wall of the side surface portion 209b corresponding to the lower side of the formation region 236R of the first gas exhaust port 236. Further, from the opening of the second gas exhaust port 237, one portion of the exhaust outlet 230 provided in the lower portion 203c of the reaction pipe (outer pipe) 203 can be seen.

According to embodiments, one or more of the following effects may be obtained.

(1) In a double reaction tube having a cylindrical tube portion (inner tube) 209 and a reaction tube (outer tube) 203 whose upper end is closed, the tube portion (inner tube) 209 has a tube portion (inner tube) A first gas exhaust port (exhaust hole, slit) 236 is provided in parallel to the central axis of the pipe 209. The first gas exhaust port (exhaust hole, slit) 236 has a maximum width W1 near the upper end of the cylindrical portion (inner pipe) 209 and a minimum width W3 near the lower end of the cylindrical portion (inner pipe) 209 And has a predetermined width W2 wider than the minimum width W3 at an end further below the position where the minimum width W3 is reached. The first gas exhaust port (exhaust hole, slit) 236 has a predetermined width W2 wider than the minimum width W3 at the lower end closer to the position where the minimum width> W3 and, therefore, the cylindrical portion (inner pipe) It is possible to prevent the flow of the processing gas into the area other than the wafer processing space 209. Thereby, the velocity distribution of the processing gas between the wafers 200 can be made uniform, so that the film thickness difference between the wafers 200 can be made uniform.

(2) In the above (1), at the positions where the maximum width W1 and the predetermined width W2 of the first gas exhaust port (exhaust hole, slit) 236 are reached, a plurality of wafers 200 stacked one on top of the other are cylindrical portions (inner pipe) The positions substantially correspond to the upper end portions of the plurality of wafers 200 and the lower end portions of the plurality of wafers 200 at the time of being placed in the space 209. Thus, the processing gas can be efficiently exhausted from the first gas exhaust port at the upper end to the lower end of the plurality of wafers 200 stacked in multiple stages. Therefore, since the velocity distribution of the processing gas among the plurality of wafers 200 stacked in multiple stages can be made uniform, the film thickness difference among the wafers 200 among the plurality of wafers 200 stacked in multiple stages can be made uniform. I can do it.

(3) In the wafers 200 loaded on the boat 217 at a constant interval (pitch) p, the upper end 236U of the first gas exhaust port (exhaust hole, slit) 236 is from the position of the wafer 200 placed on the top. Are also set high by p / 2 to 2p. In addition, the lower end 236L of the first gas exhaust port (exhaust hole, slit) 236 is set at a position lower than p / 2 by 2p than the position of the wafer placed at the lowermost portion. As a result, the uppermost wafer to the lowermost wafer of the loaded wafers 200 are positioned within the range from the upper end 235U to the lower end 235L of the first gas exhaust port 236. Thus, the first gas exhaust port 236 enables the process gas to be efficiently exhausted.

(4) The reaction tube (outer tube) 203 has an exhaust outlet 230 connected to the vacuum pump 246. The exhaust outlet 230 is an end lower than the position where the first gas exhaust port 236 has a predetermined width W3 in the same direction as the first gas exhaust port 236 when viewed from the central axis of the cylindrical portion (inner pipe) 209 It will be installed closer. Thereby, the flow of the processing gas on the wafer 200 can be made substantially uniform, and the occurrence of the flow velocity unevenness of the processing gas in the surface of the wafer 200 can be suppressed.

(5) The cylindrical portion (inner pipe) 209 has a second gas exhaust port for exhausting the purge gas at a position substantially facing the exhaust outlet 230. The purge gas on the lower side of the processing chamber 201 of the cylindrical portion (inner pipe) 209 can be positively flowed to the exhaust outlet 230. The pressure drop can be minimized by reducing the difference between the pressure at the exhaust outlet 230 and the pressure in the wafer area of the process chamber 201.

In the present example, when various exhaust ports and exhaust outlets are substantially directly opposed, it means that they are approximately opposite to each other when viewed from the central axis CA of the cylindrical portion 209. For example, the case where the straight line which ties the arbitrary positions of one opening and the arbitrary positions of the other opening may intersect central axis CA is included.

Moreover, although the reaction tube of this example was made into cylindrical shape, it is good also as cylindrical shape of not only it but a regular polygon.

This application claims the benefit of priority based on Japanese Patent Application No. 2017-162035 filed on Aug. 25, 2017, the entire disclosure of which is incorporated herein by reference.

The present invention can be applied to an apparatus for processing a semiconductor substrate or the like under reduced pressure or processing gas atmosphere or high temperature, for example, deposition such as CVD, PVD, ALD, or epitaxial growth, or processing for forming an oxide film or nitride film on the surface It can be applied to etching process and quenching process by gas.

1: Substrate processing apparatus 200: Substrate (wafer)
201: Process chamber 203: Reaction tube (outer tube)
209: Tube part (inner pipe)
230: Exhaust outlet 235: Gas supply slit 236: First gas outlet 237: Second gas outlet

Claims

A substrate processing apparatus comprising a reaction tube having a cylindrical inner tube and an outer tube, the upper end of which is closed.
The inner pipe has a first gas outlet provided parallel to a central axis of the inner pipe,
The outer pipe has an exhaust outlet,
The first gas exhaust port is
A first width portion provided at a position relatively far from the exhaust outlet;
A second width portion provided at a position closer to the exhaust outlet than the first width portion and substantially formed equal to or smaller than the width of the first width portion;
A third portion having a smaller width than the first width portion and the second width portion on the second width portion side between the first width portion and the second width portion; And a width portion of the substrate processing apparatus.
In the substrate processing apparatus of claim 1,
The substrate processing apparatus, wherein the farthest position and the position of the second width portion correspond to positions of both ends when a plurality of substrates are disposed inside the inner pipe.
In the substrate processing apparatus of claim 2,
The exhaust outlet is closer to the lower end of the reaction tube below the second width portion of the first gas exhaust port in the same direction as the first gas exhaust port when viewed from the central axis of the inner pipe. A substrate processing apparatus provided.
In the substrate processing apparatus of claim 2,
Furthermore, it has a boat which is accommodated in the inner pipe and on which the plurality of substrates are placed at a predetermined interval (p),
The upper end of the first gas exhaust port is set at a position p / 2 to 2p higher than the position of the substrate placed on the top,
The substrate processing apparatus, wherein the lower end of the first gas exhaust port is set at a position p / 2 to 2p lower than the position of the substrate placed at the lowermost part.
In the substrate processing apparatus of claim 3,
The substrate processing apparatus, wherein the inner pipe has a second gas exhaust port for evacuating a purge gas at a position facing the exhaust outlet.
The inner pipe has a gas supply slit to which a processing gas is supplied,
The substrate processing apparatus according to claim 3, wherein the gas supply slit is provided on a side wall of the inner pipe opposite to the first gas exhaust port as viewed from the central axis of the inner pipe.
The substrate processing apparatus according to claim 3, wherein the inner pipe and the outer pipe are coupled to and integrated with each other at respective lower ends.
A gas supply area formed by projecting a part of the side portion of the inner pipe to the outside so as to cover the portion where the gas supply slit is formed;
And a plurality of nozzles respectively housed in a separated state in the gas supply area,
It further comprises a boundary wall which is a part of the side wall of the inner pipe, and which forms a boundary between the gas supply area and the inner pipe,
The gas supply slit is formed as a plurality of circumferentially long openings in the boundary wall,
The substrate processing apparatus according to claim 6, wherein the gas supply slits are arranged in a plurality of rows in the circumferential direction so as to correspond to a plurality of nozzles, and arranged in a plurality of stages so as to correspond to the substrate.
7. The substrate processing apparatus according to claim 6, wherein the first gas exhaust port is formed as a single opening whose width is continuously changed by an outline formed by a combination of one or more straight lines or arcs.
4. The substrate processing apparatus according to claim 3, wherein the first width portion of the first gas exhaust port is configured by arranging a plurality of openings in the circumferential direction of the inner pipe.
The substrate processing apparatus according to claim 3, wherein the second width portion of the first gas exhaust port is configured by arranging a plurality of openings in the circumferential direction of the inner pipe.
The first gas exhaust port is constituted by a plurality of slits divided so as to open in the direction of the central axis of the inner pipe in correspondence with a plurality of positions where a substrate is disposed in the inner pipe. The substrate processing apparatus of claim 3.
In the slit divided into the plurality,
The substrate processing apparatus according to claim 3, wherein the outline of each of the divided slits is formed in a rectangular shape which is long in the circumferential direction of the inner pipe.
A reaction tube used in a substrate processing apparatus,
The reaction tube has a cylindrical inner tube and an outer tube, the upper end of which is closed.
The inner pipe has a first gas outlet provided parallel to a central axis of the inner pipe,
The outer pipe has an exhaust outlet,
The first gas exhaust port is
A first width portion provided at a position relatively far from the exhaust outlet;
A second width portion provided at a position closer to the exhaust outlet than the first width portion and substantially formed equal to or smaller than the width of the first width portion;
A third portion having a smaller width than the first width portion and the second width portion, between the first width portion and the second width portion, on the second width portion side Has a width, and
The exhaust outlet is closer to the lower end of the reaction tube below the second width portion of the first gas exhaust port in the same direction as the first gas exhaust port when viewed from the central axis of the inner pipe. The reaction tube provided.
Preparing the substrate processing apparatus according to claim 1;
Inserting a substrate holder for holding a plurality of substrates in a processing chamber in the inner tube;
A gas supply port formed in the inner pipe so that the nozzle arrangement chamber and the processing chamber communicate with each other from a gas nozzle arranged in a nozzle arrangement chamber provided to divide the gap between the outer pipe and the inner pipe. Supplying a processing gas into the processing chamber via
The atmosphere in the processing chamber is exhausted to the gap from the first gas exhaust port formed in the inner pipe so as to connect the gap and the processing chamber, and the atmosphere exhausted to the gap is the outer tube And evacuating the outer pipe from an exhaust outlet provided on the semiconductor device.
Housing the substrate in a reaction tube having an inner tube and an outer tube closed at the upper end;
Supplying a gas to the inner pipe;
By exhausting the atmosphere of the inner pipe and the outer pipe from an exhaust outlet provided in the outer pipe, a first provided in the inner pipe at a position relatively far from the exhaust outlet. A width portion, a second width portion provided at a position closer to the exhaust outlet than the first width portion, and formed substantially equal to or less than the width of the first width portion; A third width portion having a width smaller than the first width portion and the second width portion, between the width portion and the second width portion, on the second width portion side And D. discharging the gas from the first gas exhaust outlet, and processing the substrate.