JP5218039B2 - Vapor growth equipment - Google Patents

Description

  The present invention relates to a vapor phase growth apparatus. In particular, the present invention relates to a vapor phase growth apparatus including a cooling chamber for cooling a heated semiconductor wafer.

  For example, a single wafer type vapor phase growth apparatus includes a mounting chamber in which a pair of process chambers, a load lock chamber with a transfer robot, a pair of cooling chambers, and a pair of FOUPs (FOUP: Front Opening Unified Pod) are arranged. Configured.

  The process chamber is an epitaxial processing apparatus that grows an epitaxial layer by heating a semiconductor wafer. The heated semiconductor wafer after processing is received by the transfer robot in the load lock chamber and transferred to one of the cooling chambers to cool the semiconductor wafer to a predetermined temperature. Thereafter, either one of the semiconductor wafers is accommodated in a hoop.

  The above-described vapor phase growth apparatus is a horizontal conveyance type automatic conveyance apparatus capable of parallel processing of semiconductor wafers, and has excellent processing capability as a single wafer type vapor phase growth apparatus.

  In such a vapor phase growth apparatus, when a semiconductor wafer is transferred to a process chamber, for example, the semiconductor wafer is placed on a plane of a strip-like blade and transferred. This blade crosses the center of gravity of the semiconductor wafer, and is configured such that the back surface of the semiconductor wafer contacts.

  On the other hand, the process chamber includes a pair of lift pins on which both wings (regions where the blade does not contact) on the back surface of the semiconductor wafer are placed and moved up and down. The cooling chamber is provided with a pair of arc-shaped side supports on which both wings on the back surface of the semiconductor wafer are mounted and which move up and down.

  Accordingly, the semiconductor wafer can be transferred to the process chamber or the cooling chamber by moving the blade in the horizontal direction above the pair of lift pins or the pair of side supports and then lowering the blade.

  However, when a semiconductor wafer heated in the process chamber is placed on the blade, a phenomenon occurs in which both wings of the semiconductor wafer are warped downward due to temperature imbalance of the front and back surfaces of the semiconductor wafer and the influence of its own weight. .

  On the other hand, the cooling chamber includes a disk-shaped cooling plate that cools the heated semiconductor wafer to a predetermined temperature. By lowering the semiconductor wafer placed on the pair of side supports, the back surface of the semiconductor wafer is brought close to the surface of the cooling plate to cool the heated semiconductor wafer.

  For example, the cooling plate described above is configured such that the semiconductor wafer is placed on a plurality of quartz pins slightly protruding from the center of the surface, and the back surface of the semiconductor wafer is brought close to the surface of the cooling plate.

  However, the cooling plate is made of a metal body such as a stainless alloy, and when both wings of the heated semiconductor wafer are warped downwards and close to the surface of the cooling plate, both wings of the semiconductor wafer come into contact with the surface of the cooling plate. As a result, the semiconductor wafer is contaminated with metal.

  For such a problem, a cooling chamber is disclosed in which contact between the front surface of the cooling plate and the back surface of the semiconductor wafer is prevented to prevent metal contamination of the semiconductor wafer (see, for example, Patent Document 1).

  The cooling chamber according to Patent Document 1 includes a plurality of support members that keep a semiconductor wafer at a certain height from the surface of the cooling plate and are installed on an inclined portion formed on the outer periphery of the cooling plate. The support member has a support surface that partially supports the peripheral surface of the semiconductor wafer and a contact portion that contacts the cooling plate. The support member includes a member selected from a group of materials composed of quartz, alumina, ceramics, and SiC.

The cooling chamber according to Patent Document 1 is provided with the plurality of support members, so that contact between the semiconductor wafer and the inclined portion formed on the outer peripheral portion of the cooling plate can be avoided.
JP 2003-142562 A

  However, since the cooling chamber according to Patent Document 1 partially cools the semiconductor wafer on which the cooled support surface is heated, there is a concern that distortion may remain inside the semiconductor wafer due to heat shock. That is, while the plurality of support members partially cool the semiconductor wafer by heat conduction, the surface of the cooling chamber absorbs the radiant heat of the semiconductor wafer. There is a concern that distortion may remain.

  Further, in the cooling chamber according to Patent Document 1, since the support member having a high hardness comes into contact with the semiconductor wafer, there is a concern that the semiconductor wafer may be damaged. The above can be said to be the subject of the present invention.

  Accordingly, an object of the present invention is to provide a vapor phase growth apparatus having a cooling chamber, which prevents metal contamination of a semiconductor wafer and prevents damage inside and outside the semiconductor wafer.

(1) A vapor phase growth apparatus according to the present invention is a vapor phase growth apparatus including a cooling chamber that cools a heated semiconductor wafer in proximity to a metal disk-shaped cooling plate and cools the semiconductor wafer. The chamber includes a plurality of support members that are attached to the cooling plate and support peripheral edges of the semiconductor wafer at intervals in the circumferential direction. The support members are made of a heat-resistant hard synthetic resin, and the semiconductor wafer is mounted on the chamber. A circular arc-shaped top portion is provided, and the top portion has a support surface that faces the center of the cooling plate, and a step that protrudes from the support surface and partially surrounds the outer periphery of the semiconductor wafer, The arcuate top is provided with a predetermined height at which the semiconductor wafer does not contact the cooling plate, and is inclined downward toward the center of the cooling plate. To.

  (2) It is preferable that the support member further includes a pin that protrudes from a bottom surface or an outer peripheral surface that contacts the surface of the cooling plate and is detachably fixed to the cooling plate.

  According to the present invention, in the vapor phase growth apparatus including the cooling chamber, the cooling chamber includes a plurality of support members that support the semiconductor wafer, and the support surface of the support member has a predetermined height that does not contact the cooling plate. Inclined downward toward the center of the cooling plate. Therefore, since the semiconductor wafer is supported by line contact or point contact by the support member, metal contamination of the semiconductor wafer can be prevented, and damage to the semiconductor wafer can be prevented.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  First, the configuration of the vapor phase growth apparatus according to the present invention will be described. FIG. 1 is a plan view of a vapor phase growth apparatus according to an embodiment of the present invention.

  Referring to FIG. 1, the vapor phase growth apparatus 100 includes a pair of process chambers 30 and 30, a load lock chamber 20 with a transfer robot (not shown), and a pair of cooling chambers 10 and 10.

  In FIG. 1, a process chamber 30 is an epitaxial processing apparatus that heats a semiconductor wafer 1 to grow an epitaxial layer. In the load lock chamber 20, the heated semiconductor wafer (epitaxial wafer) 1 after the epitaxial process is received by the transfer robot into the load lock chamber 20, and transferred to one of the cooling chambers 10, so that the semiconductor wafer 1 is predetermined. Cool to the temperature of.

  1, the vapor phase growth apparatus 100 may be provided with a pair of unillustrated hoops adjacent to the pair of cooling chambers 10 and 10, and the semiconductor wafer 1 cooled to a predetermined temperature can be accommodated in the hoops. Further, the vapor phase growth apparatus 100 can take out the semiconductor wafer 1 from a hoop conveyed from the outside and perform an epitaxial process.

  A vapor phase growth apparatus 100 shown in FIG. 1 is a horizontal conveyance type automatic conveyance apparatus capable of parallel processing of semiconductor wafers 1 and is a single wafer type vapor phase growth apparatus.

  Next, the configuration of the cooling chamber provided in the vapor phase growth apparatus according to the present invention will be described. FIG. 2 is a plan view of a cooling chamber provided in the vapor phase growth apparatus according to the embodiment. FIG. 3 is a longitudinal sectional view of the cooling chamber according to the embodiment, and is a view taken along the line XX of FIG. FIG. 4 is a vertical cross-sectional view of the cooling chamber according to the embodiment, and is a view taken in the direction of arrows YY in FIG.

  Referring to FIGS. 2 to 4, the cooling chamber 10 includes a metal disk-shaped cooling plate 11, a pair of side supports 12 and 12, and four support members 13. A cooling medium circulates inside the cooling plate 11. Therefore, the semiconductor wafer 1 can be cooled to a predetermined temperature by maintaining the state in which the heated semiconductor wafer 1 is close to the surface 11a of the cooling plate 11 for a predetermined time.

  Referring to FIGS. 2 to 4, the side supports 12 and 12 are arranged to face each other with the cooling plate 11 therebetween. The side support 12 includes a support body 121 and a pair of arms 122 and 122. The support body 121 is disposed so as to surround the outer periphery of the cooling plate 11 and can be moved up and down. The arm 122 protrudes from the support body 121 and faces the center of the cooling plate 11. Further, a quartz seat 12 a on which the back surface of the semiconductor wafer 1 is placed protrudes from the tip of the arm 122.

  2 to 4, the cooling chamber 10 includes four support members 13 each having a rectangular parallelepiped shape. These support members 13 are attached to the outer peripheral portion of the cooling plate 11 at intervals in the circumferential direction. Accordingly, these support members 13 can support the periphery of the semiconductor wafer 1 in a distributed manner.

  In transferring the semiconductor wafer 1 to the process chamber 30, the vapor phase growth apparatus 100 shown in FIG. 1 places the semiconductor wafer 1 on the plane of a strip-like blade (not shown) and transfers it. Yes. This blade crosses the center of gravity of the semiconductor wafer 1 and is configured such that the back surface of the semiconductor wafer contacts.

  1 to 4, the semiconductor wafer 1 can be transferred to the cooling chamber 10 by moving the blade in the horizontal direction toward the upper side of the pair of side supports 12 and 12 and then lowering the blade.

  Referring to FIG. 2, as described above, a quartz seat 12 a protrudes from the tip of the arm 122, and the curved semiconductor wafer 1 does not come into contact with the metal arm 122. Can be transported. Then, when the pair of side supports 12 and 12 are lowered, the semiconductor wafer 1 is supported by the four support members 13. On the other hand, when the pair of side supports 12 and 12 are raised, the semiconductor wafer 1 can be separated from the four support members 13.

  1 to 4, the pair of side supports 12 and 12 can be configured in two stages. Then, the semiconductor wafer 1 after the epitaxial process may be placed on the lower side support, and the semiconductor wafer 1 may be accommodated in a hoop. After the semiconductor wafer 1 is transferred to the adjacent cooling chamber 10, it is accommodated in the corresponding hoop. You can also Further, the semiconductor wafer 1 before the epitaxial process can be taken out of the hoop and mounted on the upper side support.

  Next, the structure of the support member provided in the cooling chamber according to the present invention will be described. FIG. 5 is a perspective view of a support member provided in the cooling chamber according to the embodiment. FIG. 6 is a front view of the support member according to the embodiment. FIG. 7 is a plan view of the support member according to the embodiment. FIG. 8 is a left side view of the support member according to the embodiment.

  5 to 8, the support member 13 has a support surface 131 and an arc-shaped step 132. The semiconductor wafer 1 is placed on the support surface 131. The step 132 protrudes from the support surface 131. Further, the step 132 partially surrounds the outer periphery of the semiconductor wafer 1. And the support surface 131 has the circular-arc-shaped top part toward the center of the cooling plate 11 (refer FIG. 2).

  3 to 8, the arcuate top of the support surface 131 has a predetermined height at which the semiconductor wafer 1 does not contact the surface 11 a of the cooling plate 11. That is, the arcuate top of the support surface 131 is provided with a predetermined height at which both the blades of the deformed semiconductor wafer 1 do not contact the surface 11 a of the cooling plate 11. The arcuate top is inclined downward toward the center of the cooling plate 11.

  3 to 8, the support member 13 further includes a pin 13 a that protrudes from the bottom surface 133 that contacts the surface 11 a of the cooling plate 11. The pin 13a is detachably fixed to the cooling plate 11. The support member 13 is made of a heat-resistant hard synthetic resin. The pin 13a may protrude from the outer peripheral surface of the support member 13.

  5 to 8, as an embodiment, the radius of curvature R of the arc surface of the support surface 131 is preferably in the range of about 20 mm to 50 mm. The height (thickness) H of the support member 13 is preferably set in the range of about 5 mm to 10 mm. The maximum height H1 of the support surface is preferably set in a range of about 4 mm to 10 mm corresponding to the height H of the support member 13. The inclination angle θ of the arcuate top of the support surface 131 is preferably set in the range of 2 degrees to 5 degrees.

  As an embodiment, the support member 13 is preferably made of a polyimide resin (PI, PAI, PES, PEEK, etc.), which is a heat-resistant hard synthetic resin, and more preferably commercially available Vespel (registered trademark). Vespel has a continuous maximum use temperature in the range of 150 to 300 degrees, and its surface has a Rockwell strength of 40 to 60 that is softer than the semiconductor wafer 1. The surface of the support surface 131 is preferably buffed to have a smooth surface roughness.

  Next, the operation of the vapor phase growth apparatus 100 according to the present invention will be described.

  Referring to FIG. 1, the semiconductor wafer 1 immediately after being taken out from the process chamber 30 is heated to about 700 degrees. Even when the semiconductor wafer 1 is transferred to the cooling chamber 10, the semiconductor wafer 1 is kept at a temperature of about 300 degrees. Since the semiconductor wafer 1 is placed on the blade (not shown) while moving from the process chamber 30 to the cooling chamber 10, due to the temperature imbalance between the front surface and the back surface of the semiconductor wafer 1 and the influence of its own weight, The two wings of the semiconductor wafer 1 are deformed while warping downward.

  Referring to FIG. 3 or FIG. 4, when the semiconductor wafer 1 deformed in this way is brought close to the cooling plate 11, both blades of the semiconductor wafer 1 come into contact with the surface 11 a of the cooling plate 11, and the semiconductor wafer 1 is contaminated with metal. there is a possibility.

  Referring to FIG. 2 or FIG. 3, the cooling plate 11 projects a plurality of quartz pins 111 from the surface 11a. By placing the semiconductor wafer 1 on these quartz pins 111, it is intended to prevent contact with the cooling plate 11. However, these quartz pins 111 have a protruding amount from the surface 11a of the cooling plate 11 of about 1 mm, and it is difficult to contribute to preventing contact of the deformed semiconductor wafer 1.

  Therefore, the cooling chamber 10 according to the embodiment of the present invention keeps the semiconductor wafer 1 at a certain height from the surface 11a of the cooling plate 11 in order to prevent contact between the surface 11a of the cooling plate 11 and the back surface of the semiconductor wafer 1. A plurality of supporting members 13 to be maintained were provided.

  Referring to FIGS. 2 to 8, the support member 13 has a support surface 131 whose arcuate top on which the semiconductor wafer 1 is placed faces the center of the cooling plate 11. In line contact, partial cooling of the semiconductor wafer 1 is alleviated. That is, the arcuate top portion (virtual ridgeline 130) of the support surface 131 is in line contact with the back surface of the semiconductor wafer 1, and the partial heat transfer of the semiconductor wafer 1 is reduced. Accordingly, it is possible to eliminate the distortion remaining inside the semiconductor wafer due to the influence of the heat shock.

  Referring to FIG. 8, since the support member 13 is inclined downward toward the center of the cooling plate 11, it makes point contact with the back surface of the semiconductor wafer 1, and partial cooling of the semiconductor wafer 1 is relaxed. Moreover, since this downward inclined surface is supporting the periphery of the semiconductor wafer 1 at intervals in the circumferential direction, it is considered that a force directed toward the semiconductor wafer 1 acts.

  Referring to FIGS. 2 to 8, the support member 13 has an arc-shaped step 132 that protrudes from the support surface 131 and partially surrounds the outer periphery of the semiconductor wafer 1. A plurality of support members 13 are attached to the cooling plate 11 so as to be supported at intervals, thereby preventing the semiconductor wafer 1 from falling off due to vibration or the like. Note that the step 132 is not necessarily formed in an arc shape, and may be formed so as to be substantially orthogonal to the virtual ridgeline 130.

  5 to 8, the support member 13 has a pin 13a that protrudes from the bottom surface 133 that contacts the surface 11a of the cooling plate 11 and is detachably fixed to the cooling plate 11. The support member 13 can be easily exchanged using an attachment hole (not shown) drilled in the cooling plate 11.

  The support member 13 is preferably made of a heat-resistant hard synthetic resin, and the support surface 131 has a Rockwell strength 40-60 that is softer than the semiconductor wafer 1, thereby preventing damage to the semiconductor wafer 1.

  As described above, the vapor phase growth apparatus 100 according to the embodiment of the present invention prevents metal contamination of the semiconductor wafer 1 and prevents damage inside and outside the semiconductor wafer 1 in the vapor phase growth apparatus 100 including the cooling chamber 10. A vapor phase growth apparatus can be provided.

It is a top view of the vapor phase growth apparatus by one Embodiment of this invention. It is a top view of the cooling chamber with which the vapor phase growth apparatus by the said embodiment is equipped. It is a longitudinal cross-sectional view of the cooling chamber by the said embodiment, and is a XX arrow line view of FIG. It is a longitudinal cross-sectional view of the cooling chamber by the said embodiment, and is a YY arrow line view of FIG. FIG. 3 is a perspective view of a support member provided in the cooling chamber according to the embodiment. It is a front view of the support member by the said embodiment. It is a top view of the support member by the said embodiment. It is a left view of the support member by the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor wafer 10 Cooling chamber 11 Cooling plate 13 Support member 100 Vapor phase growth apparatus 131 Support surface 132 Level difference

Claims (2)

A vapor phase growth apparatus comprising a cooling chamber that cools a semiconductor wafer heated in proximity to a metal disk-shaped cooling plate,
The cooling chamber includes a plurality of support members attached to the cooling plate and supporting peripheral edges of the semiconductor wafer at intervals in a circumferential direction,
The support member is made of a heat-resistant hard synthetic resin , provided with an arc-shaped top portion on which the semiconductor wafer is placed, and the top portion projects from the support surface toward the center of the cooling plate. A step that partially surrounds the outer periphery of the semiconductor wafer,
The arc-shaped top portion is provided with a predetermined height at which the semiconductor wafer does not contact the cooling plate and is inclined downward toward the center of the cooling plate.   2. The vapor phase growth apparatus according to claim 1, wherein the support member further includes a pin that protrudes from a bottom surface or an outer peripheral surface that contacts the surface of the cooling plate and is detachably fixed to the cooling plate.

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