WO2022202334A1

WO2022202334A1 - Substrate treatment device and substrate treatment method

Info

Publication number: WO2022202334A1
Application number: PCT/JP2022/010367
Authority: WO
Inventors: 康介山本; 俊彦城
Original assignee: 東京エレクトロン株式会社
Priority date: 2021-03-22
Filing date: 2022-03-09
Publication date: 2022-09-29
Also published as: JP2022146582A

Abstract

A substrate treatment device according to the present disclosure comprises a treatment container, a first gas supply port, a first exhaust port, and recesses. The treatment container is provided with a cylinder part having an axis oriented in the longitudinal direction and storing a substrate support implement which supports a plurality of substrates in a shelf-like manner in the longitudinal direction. The first gas supply port supplies a first gas for treating each of the substrates to one side in the longitudinal direction of a substrate support area at which each of the substrates is supported within the cylinder part. The first exhaust port exhausts the first gas from the other side in the longitudinal direction of the substrate support area. The recesses are positioned at the height of each of the substrates in the inner side surface of the cylinder part and are alternately provided at the left and right as viewed along the longitudinal direction so as to form a flow passage, which causes the first gas to flow from the first gas supply port towards the first exhaust port while meandering left and right along the surfaces of each of the substrates.

Description

SUBSTRATE PROCESSING APPARATUS AND SUBSTRATE PROCESSING METHOD

The present disclosure relates to a substrate processing apparatus and a substrate processing method.

As an apparatus for processing semiconductor wafers (hereinafter referred to as "wafers"), a plurality of wafers are arranged in a shelf in a processing container, and a processing gas is supplied to the surface of each wafer to process them all at once. things are known. As an example of such an apparatus, Japanese Patent Application Laid-Open No. 2002-200003 describes a substrate processing apparatus configured to process each wafer by supplying a processing gas from the side thereof.

JP 2015-191955 A

An object of the present disclosure is to suppress the amount of gas supplied when processing a plurality of substrates supported in a shelf shape by supplying the gas.

A substrate processing apparatus according to the present disclosure includes a processing container that houses a substrate support that supports a plurality of substrates in a shelf shape in the vertical direction, and that includes a cylindrical portion whose axis faces the vertical direction;
a first gas supply port for supplying a first gas for processing each substrate to one side in the vertical direction of a substrate support area in which each substrate is supported in the tubular portion;
a first exhaust port for exhausting the first gas from the other longitudinal side of the substrate support area;
The inside of the tubular portion forms a flow path for the first gas to meander from the first gas supply port toward the first exhaust port along the surface of each of the substrates. recesses located at the height of each of the substrates on the side surface and provided alternately to the left and right when viewed along the vertical direction;
Prepare.

According to the present disclosure, it is possible to suppress the supply amount of the gas when the processing gas is supplied to the plurality of substrates supported in the form of shelves.

1 is an X-axis cross-sectional view of a film forming apparatus according to the present disclosure; FIG. 1 is a Y-axis cross-sectional view of a film forming apparatus according to the present disclosure; FIG. 1 is a perspective view of a wafer boat provided in a film forming apparatus; FIG. It is a perspective view of a cylinder part provided in a film-forming apparatus. It is a transparent perspective view of the said cylinder part. It is a perspective view of the outer cylinder part provided in the film-forming apparatus. It is a transparent perspective view of the said outer cylinder part. It is the top view which match|combined the said outer cylinder part with the 1st position. It is the top view which match|combined the said outer cylinder part with the 2nd position. FIG. 10 is an operation diagram showing the flow of gas when the outer cylindrical portion is aligned with the first position; FIG. 10 is an operation diagram showing the flow of gas when the outer cylinder part is aligned with the second position; FIG. 4 is an X-axis cross-sectional view of another example of a film forming apparatus according to the present disclosure; FIG. 4 is a Y-axis cross-sectional view of another example of a film forming apparatus according to the present disclosure; FIG. 4 is a plan view of another example of a film forming apparatus according to the present disclosure; FIG. 10 is a pressure distribution diagram showing the pressure of gas when the outer cylindrical portion is aligned with the first position; FIG. 11 is a pressure distribution diagram showing the pressure of gas when the outer cylindrical portion is aligned with the second position;

An example in which the substrate processing apparatus according to the present disclosure is applied to a film forming apparatus that forms a film on a wafer W will be described. 1 and 2 show a vertical cross-sectional view along the X-axis direction and a vertical cross-sectional view along the Y-axis direction, respectively, of the film forming apparatus 1. The X-axis and the Y-axis are horizontal axes perpendicular to each other. be. The Z-axis in the drawing is a vertical axis orthogonal to the X-axis and the Y-axis, specifically, for example, a vertical axis. In the following description, the left and right sides of the film forming apparatus 1 are referred to as the left and right sides of the film forming apparatus 1 when viewed from the front in FIG. shown as the anterior and posterior sides of the . Therefore, the X-axis direction is the left-right direction, and the Y-axis direction is the front-rear direction.

Regarding the schematic configuration of the film forming apparatus 1 , the film forming apparatus 1 includes a low-profile, generally circular processing container 10 . A wafer boat 2 which is a substrate support for supporting a plurality of wafers W in the Z-axis direction, that is, in the vertical direction, is provided inside the processing container 10 . A cylindrical portion 3 having a lid portion and an outer cylindrical portion 4 surrounding the cylindrical portion 3 are provided upright in the processing container 10 , and the wafer boat 2 is accommodated in the cylindrical portion 3 . A heating unit 14 is provided so as to surround the processing container 10 and is configured to heat each wafer W placed on the wafer boat 2 .

Further, an exhaust port 11 is formed on the left side surface of the processing container 10 . The exhaust port 11 is connected to an exhaust portion 12 that exhausts an exhaust space 12A formed between the outer cylinder portion 4 and the cylinder portion 3 and the side wall of the processing container 10 . The exhaust space 12</b>A is formed so as to extend from the outer peripheral side of the outer cylinder portion 4 to the upper side of the outer cylinder portion 4 and the cylinder portion 3 . An exhaust port (to be described later) provided in the cylindrical portion 3 is connected to the exhaust space 12A through a through hole provided in the outer cylindrical portion 4, and the exhaust from the exhaust port 11 exhausts the inside of the cylindrical portion 3 as well.

This film forming apparatus 1 forms a film on a wafer W by ALD (Atomic Layer Deposition). Therefore, the cylinder 3 contains a precursor gas containing a film precursor, a reaction gas that reacts with the precursor gas to produce a reaction product, and unnecessary precursor gas and reaction gas for purging. of purge gas are supplied. Through-holes at different positions in the cylindrical portion 3 are used as exhaust ports when the precursor gas is supplied to the wafer boat 2 and when the purge gas and reaction gas are supplied to the wafer boat 2 . The outer cylinder part 4 is used for switching the exhaust port. Further, the precursor gas, the reaction gas, and the purge gas are supplied into the cylinder portion 3 from openings at different positions in the cylinder portion 3 . By switching the exhaust position and the air supply position, the precursor gas forms a downward meandering flow while meandering left and right in the cylindrical portion 3, and the reaction gas and the purge gas flow from the front to the rear. The reason for switching the distribution route according to the type of gas will be described in detail later.

Each part of the film forming apparatus 1 will be described in detail below. A circular opening 13 is formed in the central portion of the bottom plate 10A that constitutes the processing container 10, and a circular lid 20 that closes the opening 13 is provided. A through-hole 21 is formed in the center of the lid portion 20, and a rotating shaft 24 having a support base 23 installed at the upper end thereof is inserted through the through-hole 21 along the Z-axis direction. 3, the wafer boat 2 is placed on the support table 23. As shown in FIG. A lower portion of the rotating shaft 24 is connected to a rotating mechanism 25 provided below the lid portion 20. The rotating mechanism 25 rotates the support base 23 and the wafer boat 2 clockwise in plan view during processing. A purge gas is supplied from a purge gas supply source 63 to the gap between the rotating shaft 24 and the lid portion 20, flows into the processing container 10, and is exhausted from the exhaust space 12A. By supplying the purge gas, the precursor gas and reaction gas are prevented from being supplied to a sealing mechanism (not shown) for sealing the gap between the rotating shaft 24 and the lid portion 20. there is The rotating mechanism 25 and the lid portion 20 are connected to an elevating mechanism (not shown), and by moving up and down with respect to the processing container 10 , the opening portion 13 can be opened and closed, and the wafer boat 2 can be loaded into and unloaded from the processing container 10 . be.

The wafer boat 2 includes a circular bottom plate 26 having a diameter larger than the diameter of the wafer W (300 mm), and the bottom plate 26 is supported on the support base 23 described above. For example, four columns 27 extending in the Z-axis direction are provided at equal intervals in the circumferential direction of the bottom plate 26 in a half-peripheral area of the peripheral portion of the bottom plate 26 . Four mounting portions 200 are provided above the bottom plate 26 at intervals in the Z-axis direction.

The mounting part 200 is a circular ring-shaped member whose outer diameter is the same size as the diameter of the bottom plate 26 , and its peripheral edge is supported by each support 27 . A stepped portion is formed along the entire circumference of the upper surface of the mounting portion 200, and the height of the inner peripheral edge portion is lower than that of the outer peripheral edge portion. The upper surface of the inner peripheral edge portion supports the peripheral edge portion of the wafer W as the mounting surface 28 , and the stepped portion prevents the wafer W from being displaced on the mounting portion 200 . By mounting the wafers W on each of the mounting portions 200, the wafers W are supported by the wafer boat 2 in a shelf shape in the Z-axis direction, as described above. A substrate support area extends from the height at which the wafer W at the top of the wafer boat 2 is supported to the height at which the wafer W at the bottom is supported. By the way, the wafers W supported in this manner may be described in the order counted from the top. Specifically, the second and third wafers W are the second and third wafers W counted from the top. Similarly, the mounting portion 200 and the recessed portion 32 to be described later may also be described according to the order counted from the top.

Next, the cylindrical portion 3 will be described with reference to the perspective views of FIGS. 4 and 5 as well. FIG. 5 shows the arrangement of each part formed on the inner wall of the cylindrical portion 3 omitted in FIG. In the following description of the apparatus configuration, it is assumed that the opening 13 of the processing container 10 is closed and the wafer boat 2 is accommodated in the cylindrical portion 3, unless otherwise specified. The cylindrical portion 3 is configured in a cylindrical shape with its axis directed in the vertical direction, more specifically in the Z-axis direction, and has a top plate (lid portion) 30 . A lower end of the cylindrical portion 3 is connected to the peripheral edge of the opening 13 . For the purpose of forming the above-described meandering flow, the inner peripheral surface of the cylindrical portion 3 is close to the outer edge of the mounting portion 200 of the wafer boat 2, and the inner peripheral surface of the cylindrical portion 3 and the mounting portion 200 are in close contact with each other. The distance L1 (see FIG. 1) is sufficiently smaller than the depth of the recess 32, for example 2 mm.

An upstream end of a flow path 31A for introducing the precursor gas, which is the first gas, into the cylindrical portion 3 is open on the upper surface of the edge portion of the top plate 30 of the cylindrical portion 3 . The downstream side of the flow path 31A extends downward and opens at the upper end of the inner wall of the cylindrical portion 3, forming a first gas supply port 31. As shown in FIG. The first gas supply port 31 is above the uppermost wafer W and the uppermost mounting portion 200 and opens rightward. A through hole is formed in the side wall of the cylindrical portion 3 below the lowermost wafer W and the lowermost mounting portion 200 of the wafer boat 2 in the cylindrical portion 3 to form a first exhaust port 33 . The first exhaust port 33 is formed in a slit shape along the circumference of the cylindrical portion 3 and is positioned on the right side. Since the first gas supply port 31 and the first exhaust port 33 are provided as described above, the precursor gas can be supplied to one side (upper side) in the vertical direction of the substrate supporting region in the cylindrical portion 3, In addition, the precursor gas can be exhausted from the other side (lower side) of the substrate support area.

In addition, two concave portions 32 are provided on each of the left side and the right side of the inner peripheral surface of the cylindrical portion 3 and are formed horizontally along the circumferential direction of the cylindrical portion 3 . Therefore, each concave portion 32 is formed in an arc shape in plan view. In plan view, the point that equally divides the arc of the recessed portion 32 on the left side and the point that equally divides the arc of the recessed portion 32 on the right side are along the axis P (Z-axis) of the cylindrical portion 3 and are shown in FIGS. (shown in FIGS. 8 and 9 to be described later) are sandwiched therebetween. The width of each concave portion 32 in the vertical direction is greater than the width of the mounting portion 200 in the vertical direction. The two recessed portions 32 on the left side are separated from each other in the Z-axis direction, and the two recessed portions 32 on the right side are also separated from each other in the Z-axis direction.

Regarding the two recessed portions 32 on the left side, the central portion of the height of the first stage mounting portion 200 is positioned within the height range where the upper recessed portions 32 are formed, and the height at which the lower recessed portions 32 are formed. The central portion of the height of the third stage mounting portion 200 is located in the range of . Regarding the two recesses 32 on the right side, the central portion of the height of the second-stage mounting portion 200 is positioned within the height range where the upper recesses 32 are formed, and the height at which the lower recesses 32 are formed. The central portion of the height of the fourth stage mounting portion 200 is located in the range of . The concave portion 32 and the mounting portion 200 whose center portion of the height is located within the height range of the concave portion 32 are referred to as the concave portion 32 and the mounting portion 200 corresponding to each other. In this manner, the recesses 32 are positioned at the height of the mounting portions 200 (that is, the wafers W in each stage) of each stage, and are alternately provided on the left and right when viewed along the vertical direction (Z-axis direction).

Since the concave portion 32 has the above-described vertical width, the upper end of the concave portion 32 is located above the upper surfaces of the mounting portion 200 corresponding to the concave portion 32 and the wafer W corresponding to the concave portion 32 . The lower end of the recess 32 is located below the lower surfaces of the mounting portion 200 corresponding to the recess 32 and the wafer W corresponding to the recess 32 . As will be described later, this is for the purpose of guiding the gas so that it flows step by step. The recessed portion 32 of the first stage and the recessed portion 32 of the third stage are positioned at a height offset from the mounting portions 200 of the second and fourth stages and the wafer W, and the recessed portion 32 of the second stage and the recessed portion 32 of the fourth stage The concave portion 32 is located at a height offset from the mounting portions 200 and the wafer W on the first and third stages. In other words, the concave portion 32 is provided only on one side of the mounting portion 200 and the wafer W on each stage. The first exhaust port 33 is connected to the lower portion of the recess 32 on the fourth stage. From a different point of view, the lower side of the recessed portion 32 is further recessed toward the outer side of the cylindrical portion 3 and opened to the outer peripheral surface of the cylindrical portion 3 to form the first exhaust port 33 .

Sufficient conductance is ensured with the mounting portion 200 at the portion of the cylindrical portion 3 where the concave portion 32 described above is formed. Therefore, due to the concave portion 32 and the gap formed between the wafers W by being arranged in a shelf shape, the flow path that flows from the first gas supply port 31 to the first exhaust port 33 and meanders left and right. is formed. That is, in the cylindrical portion 3, the precursor gas flows on the surface of the wafer W in one stage from one of the left end and the right end of the wafer W to the other, moves downward through the recess 32, and moves downward on the surface of the wafer W in the next stage. It flows on the surface of the wafer W from the other of the left end and the right end of the wafer W to one.

In addition, through holes are formed in five stages in the Z-axis direction in the front side wall of the cylindrical portion 3 , forming second gas supply ports 35 each opening to the inner surface of the cylindrical portion 3 . The five second gas supply ports 35 are supply ports for supplying reaction gas and purge gas as the second gas, and are formed in a slit shape extending in the circumferential direction of the cylindrical portion 3 . The second gas supply port 35 is positioned above the mounting portion 200 of each stage and below the mounting portion 200 of the lowest stage, and supplies the reaction gas and the purge gas to the front surface side and the rear surface side of each wafer W. supply.

Furthermore, through-holes are formed in five stages in the Z-axis direction in the rear side wall of the cylindrical portion 3 , forming second exhaust ports 36 that open to the inner surface of the cylindrical portion 3 . The five second exhaust ports 36 are for exhausting reaction gas and purge gas, and are formed in a slit shape extending in the circumferential direction of the cylindrical portion 3 . Since each is formed on the side wall of the cylindrical portion 3 as described above, the second gas supply port 35 and the second exhaust port 36 are arcuate in plan view, and are formed to have the same length, for example. . In a plan view, the point that equally divides the arc of the second gas supply port 35 and the point that equally divides the arc of the second exhaust port 36 face each other with the axis P of the cylindrical portion 3 interposed therebetween. Further, for example, the second gas supply port 35 and the second exhaust port 36 have the same vertical width. By supplying a reaction gas or a purge gas from the second gas supply port 35 and exhausting it from the second exhaust port 36, the gas is supplied from the front to the rear along the front surface and the back surface of each wafer W. flows.

The arrangement of the concave portion 32, the second gas supply port 35, and the second exhaust port 36 will be supplemented. In plan view, the left recess 32 and the right recess 32 are arranged so as to be each equally divided by a line passing through the axis P and along the X axis. Further, the second gas supply port 35 and the second exhaust port 36 are arranged so as to be equally divided by a line along the Y-axis passing through the axis P in plan view. With such an arrangement, both the second gas supply port 35 and the second exhaust port 36 are largely separated from each other when viewed from the precursor gas flowing from one of the left and right recessed portions 32 to the other left and right recessed portions 32 as a meandering flow. will be located. Therefore, the flow of the precursor gas is less likely to be affected by the provision of the second gas supply port 35 and the second exhaust port 36 on the peripheral surface of the tubular portion 3 . That is, the occurrence of stagnation and retention near the second gas supply port 35 and the second exhaust port 36 is prevented, and the in-plane uniformity of processing of the wafer W can be improved.

For example, nine through-holes are formed in the side wall of the cylindrical portion 3 below the second gas supply port 35 and the second exhaust port 36 to form the exhaust hole 34 . These exhaust holes 34 are arranged at equal intervals along the circumference of the cylindrical portion 3, and the purge gas supplied around the rotating shaft 24 and flowing into the cylindrical portion 3 is discharged through the cylindrical portion 3. It is configured as a channel for discharging to the outside.

Next, the outer cylindrical portion 4 surrounding the cylindrical portion 3 will be described with reference to the perspective views of FIGS. 6 and 7 as well. FIG. 7 shows the arrangement of each part formed on the inner wall of the cylindrical portion 3 omitted in FIG. The outer cylinder portion 4 is configured as a cylinder coaxial with the cylinder portion 3 . Therefore, the axis P of the tubular portion 3 described above is also the axis of the outer tubular portion 4 . The inner peripheral surface of the outer tubular portion 4 is close to the outer peripheral surface of the tubular portion 3 . As shown in FIGS. 1 and 2, the lower end side of the outer cylinder portion 4 protrudes downward from the processing container 10 through an annular opening 19 formed in the bottom plate 10A. It is supported by struts 45 provided at intervals. The column 45 is connected to a rotation mechanism 46 that rotates the column 45 about the vertical axis via an arm portion 45A. The support column 45 is formed sufficiently long so that the arm portion 45A does not hinder the lowering of the wafer boat 2 when the lid portion 20 is lowered. A purge gas is supplied from a purge gas supply source 63 to the gap between the edge of the opening 19 and the outer cylinder 4, flows into the processing container 10, and is exhausted from the exhaust space 12A. The supply of the purge gas prevents the precursor gas and the reaction gas from being supplied to a sealing mechanism (not shown) for sealing the gap formed between the edge of the opening 19 and the outer cylindrical portion 4 . I'm trying to

The rotating mechanism 46 rotates the outer tube portion 4 around the axis P relative to the tube portion 3 . More specifically, the rotation mechanism 46 rotates the outer cylinder 4 clockwise and counterclockwise in a plan view to switch the position of the outer cylinder 4 with respect to the cylinder 3 .

A first through-hole 41 , a second through-hole 42 and a third through-hole 43 are formed in the side wall of the outer cylindrical portion 4 . These through

holes

41 , 42 , 43 overlap the first exhaust port 33 , the second gas supply port 35 , and the second exhaust port 36 of the cylindrical portion 3 , respectively, so that the first exhaust port 33 , It has a role of opening the second gas supply port 35 and the second exhaust port 36 to the outside of the outer cylindrical portion 4 .

The first through hole 41 is formed in a slit shape along the circumference of the outer cylindrical portion 4 corresponding to the shape of the first exhaust port 33 . The second through holes 42 are formed vertically corresponding to the second gas supply ports 35 provided in five stages as described above, and the third through holes 43 are formed in five stages as described above. It is formed vertically corresponding to the second exhaust port 36 provided in the step. In other words, the upper end portions of the second through-hole 42 and the third through-hole 43 are positioned at the height of the second gas supply port 35 and the second exhaust port 36 on the uppermost stage. Further, the lower ends of the second through-hole 42 and the third through-hole 43 are located at the height of the second gas supply port 35 and the second exhaust port 36 at the lowest stage. Since they respectively correspond to the second gas supply port 35 and the second exhaust port 36, the second through hole 42 and the third through hole 43 are arranged to face each other. The first through hole 41 is opened at a position shifted in the circumferential direction of the outer cylindrical portion 4 with respect to the second through hole 42 and the third through hole 43 .

Description will also be made with reference to FIGS. When the outer cylinder part 4 is arranged in the first position (the position shown in FIG. 8) so that the first through hole 41 overlaps the first exhaust port 33 (in the first state), the second The through hole 42 and the third through hole 43 are separated from the second gas supply port 35 and the second exhaust port 36, respectively. That is, in the first position, the first exhaust port 33 is open to the outside of the outer cylinder portion 4, while the side wall of the outer cylinder portion 4 allows the second gas supply port 35 and the second exhaust port 36 to be opened. It is closed to the outside of the outer cylindrical portion 4 . The outer cylinder part 4 is moved to the second position (the position shown in FIG. 9) so that the second through hole 42 and the third through hole 43 overlap the second gas supply port 35 and the second exhaust port 36, respectively. 2 (in the second state), the first through hole 41 is separated from the first exhaust port 33 . That is, in the second position, the second gas supply port 35 and the second exhaust port 36 are open to the outside of the outer cylinder portion 4 , while the side wall of the outer cylinder portion 4 opens the first exhaust port 33 . It is closed to the outside of the outer cylinder part 4 . The second position is a position obtained by rotating the outer cylinder part 4 counterclockwise in a plan view by 40° with respect to the first position about the axis P as the rotation axis.

Further, nine through-holes 44, for example, are formed at equal intervals in the circumferential direction at positions near the bottom of the outer cylindrical portion 4. As shown in FIG. This through hole 44 overlaps with the exhaust hole 34 of the cylindrical portion 3 when the outer cylindrical portion 4 is set to either the first position or the second position.

A first gas supply section 5 is provided on the right side of the outer cylinder section 4 in the exhaust space 12A. The first gas supply unit 5 is configured as a pipe that is erected with respect to the bottom plate 10A of the processing container 10, and the tip side thereof is located above the upper end of the outer cylindrical portion 4. It is folded back toward the inner side of the outer cylindrical portion 4 so as to face downward. A gas supply port formed at the tip of the first gas supply part 5 is opened in proximity to the flow path 31A of the top plate 30 of the cylindrical part 3, and the first gas is supplied to the flow path 31A. can be supplied. The base end side of the first gas supply unit 5 extends downward through the bottom plate 10A and is connected to the first gas supply source 52 outside the processing container 10 . In this example, DCS (Dichlorosilane) gas, for example, is supplied from the first gas supply source 52 as the precursor gas, which is the first gas.

A second gas supply section 6 is provided on the front side of the outer cylinder section 4 in the exhaust space 12A. The second gas supply unit 6 is configured as a pipe that is wide in the left and right directions and is erected with respect to the bottom plate 10A of the processing container 10 . On the side surface of the second gas supply portion 6 facing the outer cylinder portion 4 , five-stage slits 61 are formed in the Z-axis direction while being close to the outer cylinder portion 4 . The height of the slits 61 on each stage is aligned with the height of the second gas supply port 35 on each stage of the cylindrical portion 3, and the outer cylindrical portion 4 is positioned at the second position as described with reference to FIG. Gas can sometimes be supplied from each slit 61 to each second gas supply port 35 . The base end side of the second gas supply unit 6 extends downward through the bottom plate 10A and is connected to a second gas supply source 62 and a purge gas supply source 63 outside the processing container 10, respectively. In this example, for example, ozone (O ₃ ) gas is supplied from the second gas supply source 62 as the reactive gas, which is the second gas, and for example, nitrogen (N ₂ ) gas is supplied from the purge gas supply source 63 as the purge gas. shall be

In addition, the film forming apparatus 1 is provided with a control section 90 made up of, for example, a computer. The control unit 90 includes a data processing unit including a program, a memory, and a CPU. Instructions (each step) are built in to advance the steps. This program is stored in a storage medium such as a compact disc, hard disk, DVD, or memory card and installed in the control unit 90 .

The action of the film forming apparatus 1 will be described. When the wafer boat 2 in which the wafers W are mounted on the respective mounting portions 200 is stored in the processing container 10 and the opening portion 13 of the processing container 10 is closed by the lid portion 20 , the heating portion 14 heats the processing container 10 . heated inside. On the other hand, the exhaust space 12A in the processing container 10 is evacuated by the exhaust unit 12, and the wafer boat 2 is rotated by the rotation mechanism 25. As shown in FIG. 8 by the rotating mechanism 46, the second gas supply port 35 and the second exhaust port 36 are closed, and the first exhaust port 33 is opened. and Then, the DCS gas is supplied from the first gas supply unit 5 (step S1).

This DCS gas is supplied from the right side of the uppermost wafer W as shown in FIG. 10 and flows leftward on the surface of the wafer W. Then, it descends to the left side of the wafer W in the second stage via the recess 32 in the uppermost stage and flows toward the right side of the wafer W in the second stage. After that, the DCS gas flows from one wafer W to the surface of another wafer W positioned one below the one wafer W through the concave portion 32, and flows on the surface of the other wafer W to the left and right. going from one side to the other. The gas flow on the surface of the other wafer W is in the opposite direction to the gas flow on the surface of the wafer W of one. Therefore, the DCS gas alternately flows from right to left and left to right from the uppermost wafer W toward the lower wafer W. As shown in FIG. That is, a meandering flow is formed as described above, and the DCS contained in the gas is adsorbed on the surface of each wafer W. FIG. Then, the DCS gas, which has flowed in order on the surfaces of the four wafers W, flows rightward from the surface of the wafer W in the lowest stage, flows into the first exhaust port 33 arranged on the right side of the wafer W, and flows into the first exhaust port 33. The gas is discharged into the exhaust space 12A through one through hole 41 and exhausted from the exhaust port 11. As shown in FIG.

Subsequently, the supply of the DCS gas is stopped, and the outer cylinder part 4 is rotated counterclockwise by 40° as viewed from above to be positioned at the second position shown in FIG. As a result, the first exhaust port 33 is closed, and the second gas supply port 35 and the second exhaust port 36 are opened.

Then, the purge gas is supplied from the second gas supply unit 6 (step S2), and the purge gas passes through the third through-hole 43 and the second gas supply port 35 in order to the surfaces of the wafers W in the cylindrical unit 3 and the Supplied on the back side. Since the purge gas is exhausted from the second exhaust port 36 facing each second gas supply port 35, the purge gas flows from the front to the rear along the front and back surfaces of each wafer W. 2 into the exhaust port 36 (FIG. 11). Then, it is released to the exhaust space 12A through the second through hole 42 and exhausted. As a result, the DCS gas remaining in the cylindrical portion 3 is purged and removed.

Subsequently, O ₃ gas is supplied instead of the purge gas from the second gas supply unit 6 (step S3). Similar to the purge gas, the O ₃ gas also flows from the front side to the rear side along the front and back surfaces of each wafer W and is discharged into the exhaust space 12A through the second exhaust port 36 and the second through hole 42 in order. is exhausted. By supplying the O ₃ gas in this manner, the DCS adsorbed on the wafer W reacts with the O ₃ gas to produce SiO ₂ as a reaction product. Subsequently, the purge gas is supplied instead of the O ₃ gas from the second gas supply unit 6 (step S4). This step S4 is the same operation as step S2 except that the purge target is _O3 gas instead of DCS gas.

Then, the supply of the purge gas is stopped, the outer cylinder part 4 is rotated clockwise by 40° when viewed from above, returned to the first position, and the DCS gas is supplied. That is, the above step S1 is performed again. After that, steps S2 to S4 are performed, and then steps S1 to S4 are performed. By repeating steps S1 to S4 in this manner, _SiO.sub.2 is repeatedly deposited on the wafer W as a reaction product to form a _SiO.sub.2 film. When the SiO ₂ film has a desired film thickness by repeating steps S1 to S4 a predetermined number of times, the evacuation of the processing chamber 10 is stopped, the lid 20 is lowered, and the wafer boat 2 is unloaded from the processing chamber 10 .

Regarding the precursor gas, which is the first gas, DCS was taken as an example in the previous explanation, but various gases can be used according to the type of film to be formed. As this precursor gas, a gas having a low adsorption efficiency to the surface of the wafer W may be used. If such a precursor gas were to be supplied from one end side of each wafer W and exhausted from the other end side of each wafer W in the same manner as the reaction gas and purge gas described above, most of it would remain unadsorbed to the wafer W. It will be removed from the periphery of the wafer W. Therefore, a relatively large amount of precursor gas is supplied into the cylindrical portion 3 in order to cause the wafer W to adsorb an amount necessary for film formation, which may increase the cost required for the process.

In the film forming apparatus 1, the precursor gas meanders in the cylindrical portion 3 and flows on the surface of each wafer W in order as described above. Therefore, even components in the gas that are not adsorbed when the precursor gas passes over the surface of one wafer W can be adsorbed when passing through the surface of another wafer W on the lower stage side of the one wafer W. can. Therefore, the efficiency of using the precursor gas can be increased, so that each wafer W can be processed with a relatively small supply amount of the precursor gas, and the cost required for processing can be reduced.

In addition, although the O ₃ gas was used as an example of the reaction gas in the above description, various gases can be used according to the type of film to be formed. Incidentally, depending on the type of precursor gas and reaction gas used, by-products other than the reaction products for forming the film on the wafer W may be generated, and the film quality may be deteriorated by mixing the by-products into the film. There is That is, the reaction gas that has already passed through the surface of the wafer W may contain the above-described by-products, and it is desirable that the by-products are not supplied to the other wafers W and are quickly exhausted. Therefore, in the film forming apparatus 1, as described above, the reaction gas is supplied from the second gas supply port 35 on the front side of each wafer W, and the second gas supply port 35 is opposed to the second gas supply port 35 on the rear side of the wafer W. Exhaust is performed from the second exhaust port 36 . As a result, the reaction gas that has flowed from the front to the rear on the surface of one wafer W is quickly removed from the cylindrical portion 3 and is prevented from being supplied to the other wafers W. FIG. As a result, contamination of the film of each wafer W with by-products is prevented, and a drop in the yield of semiconductor products manufactured from the wafers W can be prevented.

The purge gas is also supplied from the second gas supply port 35 and exhausted from the second exhaust port 36 in the same manner as the reaction gas. As a result, the precursor gas and reaction gas swept away by the purge gas are quickly removed from the cylindrical portion 3 and prevented from remaining in the cylindrical portion 3 for a long time. Therefore, this purge can be completed quickly, which is preferable.

By the way, the second gas supply port 35 and the second exhaust port 36 are provided in the vicinity of the concave portion 32 in the circumferential direction of the cylindrical portion 3, that is, are provided in the lateral direction, respectively, so that the reaction gas and the purge gas are not longitudinally directed. You may make it flow in a left-right direction. However, it is preferable that the second gas supply port 35 and the second exhaust port 36 are provided at a greater distance from the precursor gas that forms a meandering flow and flows between the recesses 32 as described above. . Therefore, as described above, the second gas supply port 35 and the second exhaust port 36 are preferably arranged in the front-rear direction so that the reactant gas and the purge gas form airflows in the front-rear direction.

Further, according to the film forming apparatus 1, one of the first exhaust port 33 and the second exhaust port 36 is opened in the cylindrical portion 3 by rotating the outer cylinder portion 4, but the second exhaust port is opened. The outer cylindrical portion 4 is configured so that the second gas supply port 35 is also closed when the port 36 is closed. By collectively opening and closing the second gas supply port 35 and the second exhaust port 36 in this manner, the configuration of the apparatus is simplified.

When the meandering flow is formed, both the second gas supply port 35 and the second exhaust port 36 are closed as described above, so that the gas enters the gas supply port 35 and the second exhaust port 36. As a result, turbulence of the airflow is prevented. Therefore, the uniformity of processing between the wafers W and within the surface of the wafer W can be improved. By connecting the cylindrical portion 3 instead of the outer cylindrical portion 4 to the rotating mechanism 46 and rotating it with respect to the outer cylindrical portion 4, the first exhaust port 33, the second gas supply port 35 and the second gas supply port 35 are connected. A configuration in which each of the exhaust ports 36 is opened and closed may be employed.

Further, the mounting portion 200 on which the wafer W is mounted has an outer diameter larger than the diameter of the wafer W, and the portion of the mounting portion 200 other than the portion where the concave portion 32 is formed on the inner peripheral surface of the cylindrical portion 3 is close to the perimeter. That is, the mounting portion 200 is configured to have a high gas pressure loss between it and the inner peripheral surface of the cylindrical portion 3 , and the precursor gas flows from between the cylindrical portion 3 and the mounting portion 200 . is prevented. Therefore, the amount of the precursor gas to be used can be reduced more reliably.

By the way, in the above-described film forming apparatus 1, the second gas supply port 35 and the second exhaust port 36 in the cylindrical portion 3 are provided for each wafer W in each stage. It is not limited to the configuration provided for each stage. Specifically, for example, like the second through-hole 42 and the third through-hole 43 of the outer cylindrical portion 4, the opening extends from the height of the wafer W on the uppermost stage to the height of the wafer W on the lowermost stage. It may be configured vertically as shown. Even with such a configuration, the reaction gas or the purge gas supplied onto one wafer W does not reach the surface of the other wafer W because the mounting portion 200 is close to the inner peripheral surface of the cylindrical portion 3 . is exhausted while the supply to is suppressed.

Further, in the film forming apparatus 1, the first gas supply port 31 is opened in the inner peripheral surface of the cylindrical portion 3, and the precursor gas is supplied so as to go toward the first recessed portion 32 located on the left side. That is, the recess 32 closest to one end (upper end) in the vertical direction of the plurality of recesses 32 is provided on one of the left and right sides (left side). It is configured to open on the other side (right side). However, the opening position of the first gas supply port 31 is not limited to such an opening position because it is sufficient to open so as to supply the precursor gas to the surface of the wafer W in the first stage. For example, the top plate 30 of the cylindrical portion 3 may be provided with the first gas supply port 31 and the precursor gas may be discharged downward toward the left end of the wafer W in the first stage. However, by configuring the first gas supply port 31 to open to the inner peripheral surface of the cylindrical portion 3 as described above, the gap between the surface of the wafer W in the first stage and the surface of the other wafer W can be reduced. The precursor gas flow conditions at are aligned. That is, the same airflow is formed on the surface of each wafer W, and the occurrence of variations in processing among the wafers W is prevented.

Further, the first exhaust port 33 only needs to be able to exhaust the precursor gas after passing through the surface of the wafer W in the fourth stage. Therefore, the opening is not limited to being provided at a height lower than the wafer W on the fourth tier, and may be provided at a height between the wafer W on the third tier and the wafer W on the fourth tier. good.

By the way, the film forming apparatus 1 may be configured so that the cleaning gas is supplied from the first gas supply port 31 after the film forming process. Specifically, in addition to the first gas supply source 52, which is a precursor gas supply source, a cleaning gas supply source is also connected to the first gas supply unit 5, and the precursor gas and the cleaning gas are connected. It is configured such that they are switched to each other and supplied to the first gas supply unit 5 . Even when the cleaning gas is supplied, the outer cylinder portion 4 is placed at the first position, so that the air is exhausted from the first exhaust port 33 and a meandering flow is formed. The cleaning gas removes the film formed inside the cylindrical portion 3 and on the wafer boat 2 . However, during this cleaning, the wafer boat 2 supports, for example, dummy wafers not intended for manufacturing semiconductor products in place of the wafers W. As shown in FIG. In the cleaning performed as described above, the cleaning gas meanders and stays for a relatively long time from being supplied into the cylindrical portion 3 to being exhausted from the cylindrical portion 3 . Therefore, the inside of the cylindrical portion 3 and the wafer boat 2 can be cleaned with a relatively small amount of cleaning gas supplied.

Also, the substrate processing apparatus is not limited to the film forming process, and may be an etching apparatus for etching the wafer W, in which case an etching gas is supplied as the first gas. Alternatively, the wafer W may be configured as an annealing apparatus that heats the wafer W while supplying an inert gas as the first gas. Even in these cases, the amount of etching gas and inert gas supplied can be reduced, and the cost required for processing can be reduced. Note that the film forming apparatus is not limited to performing ALD, and may perform CVD (Chemical Vapor Deposition). In that case, a film-forming gas may be supplied as the first gas.

Next, a modified example of the film forming apparatus 1 will be described with a focus on differences from the film forming apparatus 1 with reference to FIGS. 12 to 14. FIG. 12 and 13 show longitudinal sections along the X and Y axes of the device, respectively, and FIG. 14 shows a transverse plane of the device. In the film forming apparatus of this modified example, the outer cylinder portion 4 is not provided, and

exhaust pipes

110 and 111 are connected to the first exhaust port 33 and the second exhaust port 36 of the cylinder portion 3, respectively. The other ends of the

exhaust pipes

110 and 111 are connected to the common exhaust section 12, for example. Valves V1 and V2 are provided in

exhaust pipes

110 and 111, respectively. First, the valve V1 is opened to exhaust air from the first exhaust port 33, and the valve V2 is closed. Then, the precursor gas is supplied from the first gas supply unit 5, and the process of step S1 described above is performed. After the supply of the precursor gas is finished, the valve V1 is closed and the valve V2 is opened. As a result, the air is switched to be exhausted from the second exhaust port 36 . Further, the purge gas, the O ₃ gas, and the purge gas are supplied in this order from the second gas supply unit 6, and the processes of steps S2 to S4 described above are performed. As with the film forming apparatus 1, the process of steps S1 to S4 is repeated for the apparatus of this modification to perform ALD.

By switching the position of the exhaust port to be used by opening and closing the valve instead of rotating the outer cylinder 4, the form of the airflow formed in the cylinder 3 may be switched. In the apparatus of this modified example, the state in which the valve V1 is opened so as to exhaust air from the first exhaust port 33 and the valve V2 is closed corresponds to the first state, in which exhaust air is exhausted from the second exhaust port 33. The second state corresponds to the state in which the valve V1 is closed and the valve V2 is open. Valves V1 and V2 correspond to a switching mechanism.

In addition, in the apparatus of this modified example, the processing container 10 may not be provided outside the tubular portion 3 . That is, by configuring the cylinder part 3 as a processing container, the side wall of the cylinder part 3 becomes the side wall of the processing container, and each exhaust port and gas supply port may be configured to open to the processing container. That is, it is not limited to an apparatus configuration in which the side wall of the cylindrical portion 3 and the side wall of the processing container 10 are separated from each other as in the film forming apparatus 1, and the cylindrical portion 3 is provided with each exhaust port and gas supply port. can't

By the way, in the apparatus of this modified example, the location serving as the first exhaust port 33 may be used as the first gas supply port, and the location serving as the first gas supply port 31 may be used as the first exhaust port. That is, the apparatus may be configured such that the precursor gas flows as a meandering flow from bottom to top. When the precursor gas is flowed upward in this way, the first gas supply port only needs to be able to supply the first gas to the surface of the wafer W in the fourth stage. The opening is not limited to being at a height below the wafer W in the tier, but may be at a height between the wafer W in the third tier and the wafer W in the fourth tier.

Here, the arrangement of the first gas supply port 31 and the first exhaust port 33 will be summarized. The first gas supply port 31 supplies the first gas to one side of the substrate support area in the vertical direction, and the first exhaust port 33 exhausts the first gas from the other side of the substrate support area. When one side in the vertical direction is the upper side and the other side in the vertical direction is the lower side (that is, when the gas is supplied downward), the first gas supply port 31 supplies the first gas to the surface of the uppermost wafer W. The opening is above the substrate support area so that the . The first exhaust port 33 is provided for the lowermost wafer W and the wafer one level higher than the lowermost wafer W so that the first gas that has already passed through the surface of the lowermost wafer W can be exhausted. It suffices if the opening is on the lower side than the height between W.

On the other hand, when one side in the vertical direction is the lower side and the other side in the vertical direction is the upper side (that is, when the gas is flowed upward), the first gas supply port 31 is located on the surface of the lowermost wafer W. The opening should be below the height between the lowermost wafer W and the wafer W one level higher than the lowermost wafer W so that the first gas can be supplied. The first exhaust port 33 may open above the uppermost wafer W so that the first gas that has passed through the surface of the uppermost wafer W can be exhausted.

The number of wafers W held in the wafer boat 2 is not limited to five, and may be more or less than five. In the film forming apparatus 1, the wafer boat 2 is rotated by the rotating mechanism 25 during processing. Rotation may not be necessary if highly uniform processing can be performed.

As discussed above, the embodiments disclosed this time should be considered illustrative in all respects and not restrictive. The embodiments described above may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

[Verification test]
Pressure distribution in cylinder part 3 when gas is supplied from first gas supply part 5 with outer cylinder part 4 aligned with the first position using film deposition apparatus 1 shown in the embodiment of the present disclosure , and the state of formation of the airflow by the gas were obtained by simulation. Further, the pressure distribution in the cylindrical portion 3 and the state of formation of the airflow by the gas when the outer cylindrical portion 4 is set to the second position and the gas is supplied from the two gas supply portions 6 were obtained by simulation. Oxygen gas is supplied from the first gas supply unit 5 at a flow rate of 1.0×10 ⁻⁵ kg/sec, and Ar gas is supplied from the second gas supply unit 6 at a flow rate of 1.0×10 ⁻⁶ kg/sec. shall be supplied by As the purge gas flowing around the rotary shaft 24 and the outer cylindrical portion ₄ , N.sub.2 gas was supplied at a flow rate of 1.0.times.10.sup.- ⁶ kg/sec. In this test, the temperature of the wafer W was set to 300K, and the pressure at the exhaust port 11 of the processing container 10 was set to 266Pa.

15 and 16 show the case where the gas is supplied from the first gas supply section 5 with the outer cylinder section 4 set to the first position, and the case where the second gas supply section 6 is set to the second position. 10A and 10B are pressure distribution diagrams in the processing container 10 when a gas is supplied from . In more detail, FIGS. 15 and 16 show the pressure difference based on the pressure (266 Pa) of the exhaust port 11 described above. Also, in FIGS. 15 and 16, the airflows obtained by the simulation are indicated by arrows in a more simplified manner than the actual ones.

As shown in FIG. 15, when the gas is supplied from the first gas supply unit 5, the pressure gradient is such that the lower the height region defined by the wafer W in the cylindrical portion 3, the lower the pressure. was formed. According to this pressure gradient, it was confirmed that the gas forms a meandering flow as described in the embodiment, flows on the surface of each wafer W, and is exhausted to the exhaust space 12A. Moreover, the pressure difference between the surface of the wafer W on the uppermost stage and the surface of the wafer W on the lowermost stage is about 0.3 Pa, which is about 0.1% of the pressure of the exhaust port 11 described above. Therefore, it is presumed that the pressure environment in which each wafer W is placed is substantially the same, and that each wafer W is processed with high uniformity. Further, it was confirmed that when the gas was supplied from the second gas supply unit 6 as shown in FIG. 16, an air flow was formed from the front to the rear as described in the embodiment. And the pressure in the cylinder part 3 was substantially uniform. Therefore, it is presumed that each wafer W is processed with high uniformity.

1 Film forming apparatus 2 Wafer boat 3 Cylindrical part 10 Processing vessel 31 First gas supply port 33 First exhaust port 32 Recess W Wafer

Claims

a processing container containing a substrate support for supporting a plurality of substrates in a shelf-like manner in the vertical direction, the processing container comprising a cylindrical portion having an axis directed in the vertical direction;
a first gas supply port for supplying a first gas for processing each substrate to one side in the vertical direction of a substrate support area in which each substrate is supported in the tubular portion;
a first exhaust port for exhausting the first gas from the other longitudinal side of the substrate support area;
The inside of the tubular portion forms a flow path for the first gas to meander from the first gas supply port toward the first exhaust port along the surface of each of the substrates. recesses located at the height of each of the substrates on the side surface and provided alternately to the left and right when viewed along the vertical direction;
A substrate processing apparatus comprising:
a second gas supply port formed on the inner surface of the cylindrical portion for supplying a second gas to each of the substrates;
2. The substrate processing apparatus according to claim 1, further comprising: a second exhaust port for exhausting the second gas, which opens in the inner surface of the cylindrical portion so as to face the second gas supply port.
3. The substrate processing apparatus according to claim 2, wherein said second gas supply port and said second exhaust port are formed on one of the front and rear sides of said cylindrical portion and on the other side, respectively.
a first state in which the first gas is supplied from the first gas supply port and the first gas is exhausted from the first exhaust port;
a second state in which the second gas is supplied from the second gas supply port and the second gas is exhausted from the second exhaust port;
3. The substrate processing apparatus according to claim 2, wherein a switching mechanism for switching between is provided.
The cylindrical portion is separate from the side wall of the processing container,
An exhaust unit is provided for exhausting an exhaust space formed between the cylindrical portion and the side wall of the processing container,
The first exhaust port and the second exhaust port are provided in the cylindrical portion,
5. The substrate processing apparatus according to claim 4, wherein said switching mechanism comprises an opening/closing mechanism for opening and closing said first exhaust port and said second exhaust port with respect to said exhaust space.
The cylindrical portion is cylindrical,
The opening/closing mechanism is provided so as to surround the cylindrical portion in the processing container so that the outer peripheral surface thereof faces the exhaust space, and has a cylindrical shape that is coaxial with the cylindrical portion;
a rotation mechanism that rotates the outer cylinder relative to the cylinder around an axis to position the outer cylinder at a first position and a second position;
On the side wall of the outer cylinder part,
a first through hole that overlaps the first exhaust port at the first position and separates from the first exhaust port at the second position;
6. The substrate processing apparatus according to claim 5, further comprising a second through hole separated from said second exhaust port at said first position and overlapping said second exhaust port at said second position.
A second gas supply unit for supplying the second gas is provided facing the side wall of the outer cylinder in the exhaust space,
A side wall of the outer cylindrical portion is provided with a third through-hole separated from the second gas supply portion at the first position and overlapping the second gas supply portion at the second position. 7. The substrate processing apparatus according to 6.
Of the recesses provided alternately on the left and right sides, the recess located closest to one end in the vertical direction is provided on one of the left and right sides,
7. The substrate processing apparatus according to claim 6, wherein said first gas supply port opens on the other left and right sides of the inner surface of said cylindrical portion.
One end side in the vertical direction is the upper side,
the cylindrical portion includes a lid formed with a supply path connected to the first gas supply port;
6. The substrate processing apparatus according to claim 5, wherein the exhaust space is provided with a first gas supply unit for supplying the first gas upstream of the supply path.
the second gas comprises a reactive gas that reacts with the first gas adsorbed on the substrate to produce a reaction product;
5. The substrate processing according to claim 4, wherein the first state and the second state are alternately repeated such that the reaction product is repeatedly deposited to form a film of the reaction product on each of the substrates. Device.
When the second gas is alternately and repeatedly supplied with the first gas and the reaction gas,
11. The substrate processing apparatus according to claim 10, further comprising a purge gas supplied for purging the atmosphere in said processing chamber between the supply of said first gas and said supply of said reaction gas.
The substrate support includes support portions provided in a plurality of stages to support the peripheral edge portion of the substrate from below, and the outer peripheral edge of the support portion is closer to the inner surface of the tubular portion than the outer peripheral edge of the substrate. 2. The substrate processing apparatus according to claim 1, wherein the substrate processing apparatus is in close proximity.
the upper end of the recess is higher than the upper surface of the substrate corresponding to the recess and the upper surface of the supporting portion that supports the substrate;
13. The substrate processing apparatus according to claim 12, wherein the lower end of said recess is lower than the lower surface of said support.
a step of vertically supporting a plurality of substrates on a substrate support in a shelf-like manner;
housing the substrate support portion in a processing container having a tubular portion with an axis facing the vertical direction;
a step of supplying a first gas for processing the substrates from a first gas supply port to one side in the vertical direction of a substrate supporting region in which the substrates are supported in the tubular portion;
exhausting the first gas from the other longitudinal side of the substrate support area through a first exhaust port;
The first gas supply port is connected to the first exhaust port using concave portions that are positioned at the height of each of the substrates on the inner surface of the cylindrical portion and are provided alternately on the left and right sides when viewed along the vertical direction. a step of flowing the first gas meandering left and right along the surface of each of the substrates toward the substrate;
A substrate processing method comprising:
supplying a second gas to each of the substrates from a second gas supply port formed on the inner surface of the cylindrical portion;
a step of exhausting the second gas from a second exhaust port formed on the inner surface of the cylindrical portion facing the second gas supply port;
The substrate processing method according to claim 14, comprising: