JP2000286328A - Gas treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To support a substrate almost by the whole surface by a receptacle part and to deliver a substrate between the receptacle part and a conveying part, when a semiconductor wafer is treated by gas while it is being rotated. SOLUTION: A tray 4, provided with a ring 41 and an inverted L-shaped wafer support 42 provided, in such a manner that the advancing/retreating region of an outer carrying arm is formed on the three equally divided positions in the circumferential direction of the ring 41, is supported by the inner wall of the treatment chamber. A mounting part 3, which can be moved vertically and freely rotatable and having the size slightly smaller than the inner circumference of the ring 41, is raised from the lower side of the tray 4, the wafer W on the tray 4 is received, and the wafer W is supported almost by the whole surface, by bringing the wafer supporting part 42 into the groove part 34 on the surface of the mounting part 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas processing apparatus for performing a film forming process on a substrate such as a semiconductor wafer.

[0002]

2. Description of the Related Art In a manufacturing process of a semiconductor wafer (hereinafter, referred to as a wafer), there are heat treatments such as annealing, oxidation, and diffusion processing. In the case of performing a single-wafer heat treatment apparatus that performs this type of heat treatment, it is preferable that the substrate be configured to be rotatable in order to increase the uniformity of the treatment in the plane of the substrate.

FIG. 5 is a view showing an example of a conventional single-wafer heat treatment apparatus. This apparatus has a chamber 1 that constitutes a processing chamber.
A support member 11 is rotatably provided by a bearing 12 so as to support the peripheral portion of the wafer W at, for example, three points, and a lamp 14 serving as a heating means is provided above the chamber 1 via a transmission window 13. ing.

[0004]

However, it is advisable that the heat treatment apparatus be multifunctional by performing an oxidation process or a film forming process by CVD in addition to the annealing process. Here, for example, in the case of performing a film forming process, if the apparatus shown in FIG. 5 is used, the film adheres to the back side of the wafer W, causing particle contamination, and the reaction products also exist in the bearing. Gets in. In addition, when hydrogen chloride (HCl) gas used in the oxidation treatment touches the bearing, it is corroded. In addition, CVD is generally performed in a reduced-pressure atmosphere. However, in a structure in which the peripheral portion of the wafer W is supported at three points, the support of the wafer W is unstable at the time of reduced pressure, and the wafer W may be displaced or shaken up and down. There is also.

[0005] If the wafer W is supported on the entire surface, the transfer arm cannot transfer the wafer W from the transfer arm to the support when the transfer arm carries the wafer W from outside. On the other hand, FIG.
And the pins 16 are moved up and down by the elevating unit 17 from below to transfer the wafer W. According to the mounting table 15, the wafer W can be supported on the entire surface of the mounting table 15 during processing. However, there is a problem that the processing gas flows to the back side of the mounting table 15 through the through holes of the pins 16. .

The present invention has been made in view of such circumstances, and an object of the present invention is to rotate a substrate such as a wafer, which is an object to be processed, with a processing gas while rotating the substrate. It is an object of the present invention to provide a technique capable of holding the entire surface and transferring a substrate to and from a transport member. It is another object of the present invention to suppress a processing gas or a reaction product from flowing to a lower side of a mounting portion of a substrate.

[0007]

A gas processing apparatus according to the present invention is a gas processing apparatus which performs processing while supplying gas to a substrate which is carried into a processing chamber by a transfer unit and is supported substantially horizontally. And a tray provided in the processing chamber for supporting the tray, and a standby at a lower side of the tray. A mounting portion for supporting substantially the entire surface of the substrate, and a driving portion for raising and lowering the mounting portion and rotating the mounting portion around a vertical axis; After the transfer, the mounting portion is raised to support the tray and the substrate, and the substrate is processed while rotating the mounting portion.

In the present invention, the tray includes a ring portion formed along the circumferential direction of the processing chamber, and a substrate support portion protruding inward from the ring portion. A recess is formed for the substrate support to enter,
When the mounting portion is raised, the substrate on the substrate supporting portion is transferred to the mounting portion, and the substrate supporting portion can be hidden in the concave portion. A first cylindrical portion projecting downward is formed at a lower portion of the mounting portion, while a first cylindrical portion projecting upward is formed at a lower portion of the processing chamber, and has a diameter similar to the diameter of the first cylindrical portion. It is preferable that the second tubular portion is formed, and that the first tubular portion and the second tubular portion overlap each other when the placing portion places the substrate. Further, it is preferable to supply a purge gas from a purge gas supply unit to a through space in which a shaft for rotating and raising and lowering the mounting unit penetrates the processing chamber.

[0009]

FIG. 1 is a sectional view showing an embodiment of a gas processing apparatus according to the present invention. This apparatus includes a cylindrical chamber 20 forming the processing chamber 2, and the bottom surface of the processing chamber 2 is constituted by a transmission window 21 made of, for example, quartz. A shaft 2 is provided at the center of the transmission window 21.
2 is vertically penetrated, and the shaft 22 is configured to be able to move up and down by a driving unit 23 and to be rotatable around a vertical axis.

A mounting section 3 is provided above the shaft 22, and a tray-4 for temporarily placing a wafer W is supported by a tray support section 40 above the mounting section 3. As shown in FIG. 2, the tray-4 includes a ring portion 41 formed along the circumferential direction of the processing chamber 2 and three substrates provided at three equally-spaced positions in the ring portion 41 in the circumferential direction. And a wafer support portion 42 as a support portion. Each of the wafer support portions 42 is formed of an L-shaped thin member, and includes a vertical portion 42a that stands vertically on the inner peripheral edge of the ring portion 41 and the vertical portion 42a.
And a horizontal portion 42b which is bent inward and extends horizontally.

The tray support portion 40 is provided in a ring shape along the inner wall of the chamber 20, and the ring portion 41 of the tray-4 is mounted and supported thereon. The horizontal portion 42b is a portion on which the wafer W is placed. The horizontal portion 42b has an advance / retreat area where a wafer transfer arm, which will be described later, can advance and retreat between a position where the wafer W is supported on the horizontal portion 42b and the outside of the ring portion 41. In order to secure it, it is located higher than the upper surface of the ring portion 41.

On the other hand, the mounting portion 3 has a cylindrical portion 31 which is a first portion having a diameter slightly smaller than the inner diameter of the ring portion 41, and a second portion formed to project outward from a lower portion of the cylindrical portion 31.
A flange portion 32 as a portion and a cylindrical portion 33 forming a first tubular portion extending downward from an outer edge portion of the flange portion 32 are provided. A groove 34 is formed in the upper surface of the cylindrical portion 31 at a position corresponding to the horizontal portion 42b of the tray-4. The groove 34 is a recess into which the horizontal portion 42b enters. The portion 42b is hidden, and the wafer W previously supported by the horizontal portion 42b is transferred to the upper surface of the cylindrical portion 31.

The positional relationship between the upper surface of the cylindrical portion 31 and the upper surface of the flange portion 32 is such that when the upper surface of the cylindrical portion 31 slightly rises above the horizontal portion 42b and receives the wafer W, the flange portion 32 Is set so that the upper surface thereof contacts the lower surface of the ring portion 41 of the tray-4.

A second cylindrical portion 24 whose outer diameter is slightly smaller than the inner diameter of the first cylindrical portion 33 is provided upward from the bottom wall of the chamber 20. The lengths of the first and second cylindrical portions 33 and 24 are set so as to overlap each other in the radial direction of the chamber 20 even when in the position for receiving W. The central portion of the transmission window 21 is bent downward to form a cylindrical portion 25, and a cylindrical case 26 is fitted in the cylindrical portion 25 in an airtight manner. It penetrates this. An N2 gas supply pipe 27 serving as a purge gas supply section is connected to the case 26, from which N2 gas is supplied into the through space of the shaft 22.
The processing gas is prevented from reaching the bearing inside. Below the transmission window 21, a heating source 50 such as a lamp is provided. A gas supply unit 5 called a shower head or the like is provided at an upper portion of the chamber 20 so as to face the wafer W on the mounting unit 3. The processing gas supplied from a gas supply source (not shown) is The wafer W is supplied from the gas holes of the supply plate 51. Although not shown, exhaust ports are formed below the tray support portion 40 on the side wall of the chamber 20, for example, at four positions where the circumferential direction of the chamber 20 is divided into four equal parts.

Next, the operation of the above embodiment will be described with reference to FIG. First, a wafer W as a substrate is placed on a transfer arm 6 as a transfer unit from outside the processing chamber 2 and is loaded into the processing chamber 2 through a transfer port (not shown). FIG. 3A shows this state, in which the transfer arm 6 is positioned above the tray 4 such that the respective centers of the wafer W and the tray 4 substantially coincide with each other. Subsequently, when the transfer arm 6 is lowered, the wafer W is delivered to the wafer support portion 42 of the tray 4 as shown in FIG. 3B, and is supported at three places. After the wafer W is separated, the transfer arm 6 is extracted to the outside of the processing chamber 2 through a gap between the wafer W and the ring portion 41 secured by the vertical portion 42a of the wafer support portion 42.

Thereafter, the transfer port (not shown) is closed, and the mounting section 3 is raised, and the horizontal section 42 of the wafer support section 42 is closed.
b is hidden in the groove 34 of the mounting portion 3, and the wafer W is transferred from the wafer support portion 42 to the mounting surface (upper surface) of the mounting portion 3. After the mounting surface of the mounting portion 3 is slightly higher than the horizontal portion 42b of the wafer support portion 42, the upper surface of the flange portion 32 of the mounting portion 3 contacts the lower surface of the ring portion 41 of the tray 4,
The tray 4 floats from the tray support 40. That is, FIG.
As shown in (c), the mounting table 3 lifts the wafer W, and further supports and raises the tray 4.

Thereafter, the wafer W is heated to a predetermined temperature by the heating source 50, for example, by radiant heat of a lamp, and a predetermined gas process is performed. As an example of the gas treatment, for example, low-pressure CVD (chemical vapor deposition)
), oxidation treatment and the like. When performing low-pressure CVD, the processing chamber 2 is evacuated through an exhaust pipe (not shown), and the film forming gas is supplied to the wafer W while maintaining the reduced-pressure atmosphere.
To perform a film forming process. In this case, an electrostatic chuck may be provided on the mounting table 3, and the wafer W may be attracted to the mounting table 3 by the electrostatic chuck. The electrostatic chuck embeds an electrode made of a metal foil on the surface of the mounting table 3 and applies a DC voltage to the electrode to attract the wafer W to the mounting table 3 by electrostatic force.

In the oxidation process, for example, the wafer W is
The wafer W is heated to around 0 ° C., and hydrogen chloride gas and water vapor are supplied to oxidize the surface of the wafer W. Further, the annealing treatment may be performed by this apparatus. In this case, the treatment is performed while supplying an inert gas such as N2 gas. However, the gas treatment referred to in the present invention includes this annealing treatment. Such processing is performed while rotating the wafer W around the vertical axis by the shaft 22. After the gas processing is completed, the mounting table 3 is lowered, the tray 4 is transferred to the tray support 40, and the wafer W is placed on the tray 4.

According to such an embodiment, the wafer W can be transferred between the transfer arm 6 and the mounting table 3 via the tray 4, and the wafer W contacts the mounting table 3 almost entirely during gas processing. In this state, the gas is supported on the back surface side of the wafer W, so that, for example, in the case of a film forming process, adhesion of reaction products is reduced, and During the transfer of the wafer W, the generation of particles can be reduced. Further, for example, the wafer W is stably held even when the inside of the processing chamber 2 is set to a reduced pressure atmosphere. The contact between the flange portion 32 of the mounting table 3 and the ring portion 41 of the tray 4 prevents gas from flowing from the inside of the ring portion 41 to the lower side, and the first cylindrical portion 33 of the mounting table 4. And the second cylindrical portion 24 of the chamber 20 overlap each other, so that a labyrinth (maze) is formed between the inner space and the outer space of the mounting table 4, and the N 2 gas is purged into the through space of the shaft 22. The transmission window 21
Gas does not easily come into contact with the bearing of the shaft 22 or the shaft 22, so that the thin film of the transmission window 21 is prevented from being attached and the bearing is prevented from being corroded. Note that the first tubular portion 33 may be inside and the second tubular portion 24 may be outside.

In the above, according to the present invention, the tray may be configured as shown in FIG. In this example, a cutout 71 large enough to allow the transfer arm 6 to pass therethrough is formed in a part of the ring portion 70 to secure an advance / retreat area of the transfer arm 6, and the wafer support is formed so as to protrude inward of the ring portion 70. The tray 7 is formed by forming the portion 72. In this case, the transfer arm 6 goes downward through the notch 71, whereby the wafer can be transferred to the wafer support 72.

[0021]

According to the present invention, when the substrate is processed with the processing gas while being rotated, the substrate can be supported on almost the entire surface by the mounting portion, and the processing gas and the reaction products are deposited on the back side of the substrate. It is possible to suppress the wraparound, and it is possible to suppress the processing gas and the reaction product from wrapping under the substrate mounting portion.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an embodiment of a gas processing apparatus of the present invention.

FIG. 2 is an exploded perspective view showing a tray and a mounting portion of the embodiment of FIG.

FIG. 3 is an explanatory diagram showing an operation of the embodiment.

FIG. 4 is a perspective view showing another example of a tray.

FIG. 5 is a sectional view showing an example of a conventional gas processing apparatus.

FIG. 6 is a cross-sectional view illustrating an example of a mounting table used in a conventional gas processing apparatus.

[Explanation of symbols]

 Reference Signs List 2 processing chamber 20 chamber 21 transmission window 22 shaft 24 second cylindrical part 27 purge gas supply part 3 mounting part 34 groove part 33 first cylindrical part 4 tray 41 ring part 42 wafer support part 5 gas supply part 50 heating source

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/26 H01L 21/26 Q (72) Inventor Takeshi Ken Sakuma 1-2-2 Machiya, Shiroyamacho, Tsukui-gun, Kanagawa Prefecture No. 41 Tokyo Electron Tohoku Co., Ltd. Sagami Business Office (72) Inventor Eisuke Morisaki 1-2-1 Machiya, Shiroyama-cho, Tsukui-gun, Kanagawa Prefecture F-term (reference) 4G075 AA24 BA02 BD03 BD14 DA02 EA02 EB01 EC01 ED01 ED08 FB02 4K030 EA06 GA06 GA12 KA45 5F031 CA02 DA13 FA01 FA12 HA05 HA16 HA24 HA58 HA59 MA28 MA30 5F045 AA06 AA20 AC13 AC15 AD14 DP03 DP28 EB02 EK12 EM03 EM05 EM10 EM09 EM09 EM09 EM09

Claims (4)

[Claims] 1. A gas processing apparatus for carrying out a process while supplying gas to a substantially horizontally supported substrate carried into a processing chamber by a transfer unit, wherein the substrate is supported substantially horizontally, and the transfer unit is moved forward and backward. A tray having an area formed therein, a tray support provided in the processing chamber, for supporting the tray, and a stand-by under the tray to support substantially the entire surface of the substrate. And a drive unit for raising and lowering the mounting unit and rotating the mounting unit around a vertical axis. After the substrate is transferred to the tray by the transfer unit, the mounting unit is raised. A gas processing apparatus for supporting a tray and a substrate, and performing processing on the substrate while rotating the mounting portion. 2. The tray has a ring portion formed along the circumferential direction of the processing chamber, and a substrate support portion projecting inward from the ring portion, and the mounting portion has the substrate support portion. A concave portion for receiving the portion, wherein the substrate on the substrate supporting portion is transferred to the mounting portion and the substrate supporting portion is hidden in the concave portion when the mounting portion is raised. Item 2. The gas processing apparatus according to Item 1. 3. A lower part of the mounting portion has a first protruding lower side.
And a second cylindrical portion having a diameter approximating the diameter of the first cylindrical portion is formed at a lower portion of the processing chamber so as to project upward. 3. The gas processing apparatus according to claim 1, wherein when the substrate is placed, the first tubular portion and the second tubular portion overlap each other. 4. The mounting section is provided on a shaft that rotates and moves up and down, and the shaft is configured such that a purge gas is supplied from a purge gas supply section to a through space penetrating the processing chamber. The gas processing apparatus according to claim 1, 2 or 3, wherein