JP2008153413A - Support structure for wafer holder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable supporting structure of a wafer holder, capable of preventing damage of a wafer holder in addition to uniformly heating a wafer. <P>SOLUTION: The supporting structure supports a wafer holder 1 having an electric circuit embedded in a ceramic sintered body or on its surface with a cylindrical supporting member 3. In the supporting structure, a flange part 2 having a thread formed thereon is attached on the wafer holder 1 with a plurality of screws 4, and a thread provided on the cylindrical supporting member 3 is mated with the thread of the flange part 2. The cylindrical supporting member 3 mated with the flange part 2 is fixed with rotation preventing pins 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a support structure for supporting a wafer holder used in a semiconductor manufacturing apparatus or inspection apparatus on a cylindrical support member.

  Conventionally, various shapes have been proposed as wafer holders for semiconductor manufacturing apparatuses and inspection apparatuses. For example, Japanese Patent Publication No. 06-028258 proposes a structure in which a convex support is attached to a wafer holder. In this support structure, the convex support member is hermetically sealed with respect to the wafer holder, and an electrode or the like for supplying power to the heater can be installed therein. As a result, power supply components such as electrodes can be protected from the corrosive atmosphere in the chamber in which the wafer holder is installed.

  In the support structure described in the above Japanese Patent Publication No. 06-028258, when the wafer holder is installed in the chamber, an O-ring is generally used to hermetically seal the convex support member with the chamber. Yes. The heat-resistant temperature of the O-ring is generally about 200 ° C., but the temperature of the wafer holder is about 300 to 800 ° C., which is considerably higher than the temperature on the chamber side of the convex support. For this reason, a stress due to a temperature difference is generated between the convex support and the wafer holder, which may cause damage to the wafer holder. In particular, as described in Japanese Patent No. 28988838, this tendency is particularly remarkable when the temperature of the central portion of the wafer holder is lower than that of the outer peripheral portion.

  In recent semiconductor manufacturing, it is required to improve the thermal uniformity of the wafer holder and to form a film having a uniform thickness on the wafer. However, when heating is performed by a heating element embedded in the wafer holder, the temperature at the peripheral edge decreases due to heat radiation from the side surface of the wafer or the wafer holder, and sufficient thermal uniformity cannot be obtained. Therefore, the temperature of the wafer holder has been made uniform by setting the temperature at the center of the wafer holder lower than that of the outer periphery.

  In addition, when a convex support member is bonded to the wafer holder, the heat escape from the bonded portion is particularly large, so that the thermal uniformity near the center of the wafer holder is disturbed and the convex support is provided. Since the stress applied to the bonded portion of the member also increases, the wafer holder is often damaged. As described above, if the temperature of the central portion of the wafer holder is lower than that of the outer peripheral portion, the stress applied near the junction between the wafer holder and the convex support member is further increased, and there is a risk of damage to the wafer holder. It gets bigger.

  Also, the mounting portion of the support member (shaft) with the wafer holder was flanged, a screw hole for a female screw was formed from the flange portion to the wafer holder, and a male screw was formed thereon. A method of screwing with bolts is also conceivable. However, in this method, the bolts attached have a structure that protrudes from the flange portion of the shaft, and the flow of gas used in the process is obstructed, and corrosion of the protrusion progresses, causing particles to be generated. This is not preferable. Further, in such a structure, there is a problem that the attached bolt is loosened due to vibration or the like when the wafer holder is moved up and down, or dropped in the worst case.

Japanese Patent Publication No. 06-028258 Japanese Patent No. 2898838

  In view of the above-described conventional circumstances, the present invention not only can uniformly heat a wafer, but also can prevent damage to the wafer holder, and is a highly reliable wafer in which the support member and the wafer holder are bonded. An object of the present invention is to provide a support structure for a holding body.

  In order to achieve the above object, the support structure for a wafer holder provided by the present invention is a support structure for supporting a wafer holder in which an electric circuit is embedded in a ceramic sintered body or on a surface thereof with a cylindrical support member, A flange part having a thread formed on the wafer holder is attached, and the thread provided on the cylindrical support member is screwed to the thread of the flange part.

  In the wafer holder supporting structure according to the present invention, the flange component is screwed to the wafer holder with a plurality of screws. Further, it is preferable that a screw for screwing the flange part to the wafer holder is attached to the inside of the flange part.

In the support structure for a wafer holder according to the present invention, the difference in thermal expansion coefficient between the wafer holder, the flange part, and the cylindrical support member is preferably 2.0 × 10 ⁻⁶ / K or less. The difference in thermal expansion coefficient between the screw for fixing the flange part to the wafer holder and the flange part and the wafer holder is preferably 2.0 × 10 ⁻⁶ / K or less.

  In the support structure for a wafer holder according to the present invention, the material of the wafer holder is preferably aluminum nitride. The material of the flange part and the cylindrical support member is preferably any of aluminum nitride, mullite-alumina composite, silicon carbide, silicon nitride, and alumina.

  In the wafer holder supporting structure according to the present invention, the wafer holder and the flange part are abutted at the plane part, and the flange part and the cylindrical support member are abutted at the plane part and are abutted with each other. It is preferable that the flatness of each flat portion is 0.2 mm or less.

  In the wafer holder support structure according to the present invention, it is preferable that the cylindrical support member screwed into the flange part is fixed by a detent pin inserted from a lateral hole provided in the flange part.

  In the wafer holder supporting structure according to the present invention, the pitch of the thread of the flange part and the cylindrical support member that are screwed together is 3 mm or less, and the diameter of the screw is 30 mm or more. Is preferred. Furthermore, the thread provided on the flange part and the cylindrical support member is preferably such that the flange part is a female screw and the cylindrical support member is a male screw.

  The present invention also provides a semiconductor manufacturing apparatus, wherein the support structure for supporting the wafer holder on the cylindrical support member is the support structure for the wafer holder of the present invention.

  According to the present invention, not only is it excellent in heat uniformity when heating a wafer, but also the stress in the vicinity of the support portion of the wafer holder by the cylindrical support member can be reduced, and damage to the wafer holder can be prevented. Thus, since the bonding reliability between the wafer holder and the cylindrical support member can be improved, a highly reliable support structure for the wafer holder can be provided.

  As shown in FIG. 1, a wafer holder supporting structure according to the present invention has a flange part 2 attached to a wafer holder 1, and a thread provided on a cylindrical support member 3 on the thread of the flange part 2. The wafer holder 1 is supported by the cylindrical support member 3 by screwing together.

The method for attaching the flange part to the wafer holder is not particularly limited, but a method such as screwing or bonding can be used. In the case of attaching by bonding, for example, bonding agents such as AlN—Al ₂ O ₃ —Y ₂ O ₃ and Nd ₂ O ₃ —Yb ₂ O ₃ —CaO, glass, brazing material, and the like can be used. Among these, considering contamination of the wafer, an AlN—Al ₂ O ₃ —Y ₂ O ₃ -based bonding agent is preferable because it does not contain a metal component or an alkaline earth metal.

  Further, the flange component can be attached to the wafer holder with a plurality of screws. In the case of screwing, since there is a gap between the wafer holder and the screw, the stress generated by the temperature difference can be reduced compared to the case of bonding as described above. Further, in the present invention, since the cylindrical support member is also fixed to the flange portion with screws, the thermal stress can be further reduced. Further, in the case of screwing, an interface exists between the flange part and the wafer holder, so that the amount of heat transfer to the cylindrical support member can be reduced compared to the case of joining. . Furthermore, since the flange part and the cylindrical support member are coupled by screws, the amount of heat transferred to the cylindrical support member can be further reduced. As a result, it is possible to reduce the escape of heat from the coupling portion with the wafer holder to the cylindrical support member, and to prevent the temperature near the center of the wafer holder from being lowered. Obtainable.

  As shown in FIG. 1, the position of the screw 4 for attaching the flange part 2 to the wafer holder 1 is preferably installed inside the flange part 2. When this screw position exists inside the flange part, thermal stress is generated due to the temperature difference between the wafer holder and the flange part, but the distance between the screws becomes smaller on the inner side compared to the outer side, and added. This is preferable because the thermal stress is smaller than that when installed on the outside. Even when the screw is a metal, the screw can be protected from a corrosive gas atmosphere such as fluorine or chlorine used in the chamber. Furthermore, by flowing an inert gas such as nitrogen, argon or helium in the cylindrical support member, the screw inside the flange part can be protected from corrosion.

  The flange part is formed with a thread for screwing with a thread provided on the upper end of the cylindrical support member. When a male screw is formed on the flange component, a female screw is formed on the cylindrical support member, and when a female screw is formed on the flange component, a male screw is formed on the cylindrical support member. The flange part and the cylindrical support member can be coupled by screwing the formed threads. In this case, since the amount of heat transfer from the flange part to the cylindrical support member can be reduced compared to the case where the flange part and the cylindrical support member are joined with glass or the like, the heat to the lower part of the cylindrical support member can be reduced. The escape becomes smaller, and further, it is possible to prevent a decrease in heat uniformity.

  Further, the thread formed on the flange part is preferably a female thread as shown in FIG. Since the temperature of the flange component is relatively higher than that of the cylindrical support member, the flange component has a larger thermal expansion amount than that of the cylindrical support member. Further, since the flange part and the cylindrical support member are screwed together, the amount of heat transfer to the cylindrical support member is reduced, and a temperature difference is likely to occur between the cylindrical support member and the flange part. At this time, when the flange part is a male screw, the cylindrical support member provided with the female screw existing outside the flange component may be pressed and damaged. However, when the flange part is an internal thread, the cylindrical support member provided with the external thread is present inside the flange part, and thus the above-described problem of damage due to the temperature difference between the parts does not occur.

  In addition, since the screw for fixing the flange exists inside, the cylindrical support member itself is flanged and the process gas flow disturbance and particles generated when screwing to the wafer holder are prevented. Since it can reduce, it is preferable. Naturally, it is preferable because the bolt can be prevented from dropping.

The screw for screwing the flange part to the wafer holder preferably has a thermal expansion coefficient difference of 2.0 × 10 ⁻⁶ / K or less between the wafer holder and the flange part. If the difference in thermal expansion coefficient is larger than 2.0 × 10 ⁻⁶ / K, the wafer holder or the flange part may be damaged during heating, which is not preferable. For example, when the material of the wafer holder and the flange component is aluminum nitride, examples of the screw material include ceramics mainly composed of aluminum nitride, silicon nitride, silicon carbide, and metals such as tungsten, molybdenum, and kovar. Can be selected in consideration of the use conditions.

  In particular, when a metal screw is used, it is preferable to form a corrosion-resistant film such as nickel on the surface. Examples of the method for forming the corrosion-resistant film include thermal spraying and plating. However, plating is preferable from the viewpoint of cost and durability. The thickness of the corrosion resistant film is preferably 0.1 to 50 μm. If the thickness is less than 0.1 μm, the corrosion resistance tends to decrease, which is not preferable. On the other hand, if the thickness exceeds 50 μm, the corrosion resistant film may be peeled off due to the difference in thermal expansion coefficient with the underlying screw material due to the temperature cycle.

  Also, for the screw that fixes the flange part, a counterbore part is formed so as to straddle the head part of the screw and the flange part, and a non-rotating pin having a diameter substantially the same as the inner diameter of the counterbore part is inserted into that part. It is also possible to do. As shown in the figure, when the wafer holder is set in the chamber, this non-rotating pin is covered with the cylindrical support member, so there is no fear of dropping, and the screws that secure the flange parts are firmly It is preferable because it is fixed. Of course, it is needless to say that the anti-rotation pin can have the same material as the screw described above and a corrosion-resistant film.

Moreover, it is preferable that the difference in thermal expansion coefficient between the wafer holder, the flange component, and the cylindrical support member is 2.0 × 10 ⁻⁶ / K or less. If the difference in coefficient of thermal expansion is greater than 2.0 × 10 ⁻⁶ / K, the wafer holder, flange part, or cylindrical support member may be damaged during heating, which is not preferable.

  The material of the wafer holder is preferably a ceramic having excellent corrosion resistance against the corrosive gas used in the chamber. Suitable ceramics include alumina, aluminum nitride, silicon carbide, silicon nitride, mullite, mullite-alumina composite, and the like. In particular, aluminum nitride is preferable because it is excellent in thermal conductivity and soaking, and is excellent in corrosion resistance against corrosive gases. Since aluminum nitride is a hardly sintered material, it may contain a small amount of sintering aid. Particularly, those containing 1% or less of a rare earth element such as yttrium are excellent in sinterability and hardly corrode from the auxiliary component.

  As the material for the flange part and the cylindrical support member, ceramics excellent in the corrosion resistance in the corrosive gas atmosphere used in the chamber, and aluminum nitride is particularly preferable. In addition, the mullite-alumina composite has a relatively low thermal conductivity, so that heat escape from the contact portion between the flange part and the wafer holder can be reduced, so that it has excellent thermal uniformity and the cost is lower than that of aluminum nitride. It is preferable because it is inexpensive. About these materials, it can be used properly according to a use. That is, aluminum nitride is preferred when used in a relatively strong corrosion-resistant atmosphere, and mullite-alumina composite is preferred when soaking is required. For example, the flange part can be aluminum nitride and the cylindrical support member can be a mullite-alumina composite or vice versa.

  In the support structure of the present invention, it is preferable that the wafer holder and the flange part are screwed in a state where they are abutted with each other at the flat surface portion. By abutting the wafer holder and the flange part with each other at the plane portion, it is possible to prevent the atmosphere in the chamber from entering the cylindrical support member. This is particularly effective when an inert gas is injected into the cylindrical support member.

  It is preferable that the flat portions of the wafer holder and the flange component which are abutted with each other have a flatness of 0.2 mm or less. By setting the flatness of the flat portions that are in contact with each other to 0.1 mm or less, it is possible to prevent the atmospheric gas from entering more effectively and to reduce the backlash at the time of assembling each other's parts. Is particularly preferable.

  In addition, the flange part and the cylindrical support member preferably have a structure in which they are abutted with each other at the plane portion. By abutting each other at the flat portion, it is preferable because the atmosphere can be prevented from entering from the outside and the assembling accuracy can be improved as in the case of assembling the flange part and the wafer holder. In particular, it is extremely advantageous in that the relative position of the wafer holder within the chamber can be determined by the height of the cylindrical support member.

  The flat portions of the flange part and the cylindrical support member that are abutted to each other preferably have a flatness of 0.2 mm or less, and particularly 0.1 mm or less to achieve stable mounting and high accuracy. Is more preferable because On the other hand, if the flatness exceeds 0.2 mm, the contact of each component becomes unstable, so that the heat uniformity is lowered and the temperature of the wafer tends to vary, which is not preferable.

  Further, in the support structure of the present invention, as shown in FIG. 1, it is preferable that the cylindrical support member 3 screwed into the flange part 2 is fixed by a rotation stop pin 5. Moreover, if the rotation prevention pin is inserted from the side hole provided in the side surface of the flange part, the rotation prevention pin can be prevented from dropping and a stable structure can be obtained. With this rotation-preventing pin, it is possible to prevent the screwing of the cylindrical support member from being loosened due to vibration when the wafer holder is used and vibration due to the lift pin or the wafer holder being vertically moved. With respect to the detent pin, it is possible to effectively prevent loosening of the cylindrical support member by disposing at least one, preferably 2 to 4, locations on the side surface of the cylindrical support member.

  As the material of the detent pin, a material having a thermal expansion coefficient relatively close to that of the cylindrical support member or the flange component is preferable. Metal such as molybdenum, tungsten, and kovar, aluminum nitride, silicon nitride, alumina, silicon carbide, mullite -Ceramics such as alumina composites can be used. It is also possible to combine the above metals and ceramics. That is, as shown in FIG. 1, a rotation prevention pin 5 for fixing the cylindrical support member 3 is made of metal, and a ceramic cap screw 6 is arranged outside the rotation prevention pin 5, so that It is possible to prevent the stop pin 5 from being exposed to the atmosphere in the chamber.

  It is preferable that the pitch of the screw thread of the flange part and the cylindrical support member that are screwed together is 3 mm or less. When the thread pitch is larger than this, particularly in the case of screws between ceramics, the backlash between the flange part and the cylindrical support member becomes large, which is not preferable. The preferable pitch of the screw thread is 2.0 mm or less. However, if the pitch is less than 0.5 mm, the thread strength is reduced, and chipping is likely to occur.

  As a matter of course, the larger the number of threads and the greater the number of rotations of the screw, the more stable the connection can be achieved. Therefore, the thread pitch is 3 mm or less as described above, and the number of rotations of the screw is 3 or more. It is preferable to do. Further, the diameter of the flange part and the screw (shaft) of the cylindrical support member is preferably 30 mm or more. If the diameter of the screw is 30 mm or more, the contact area of the screw formed on the flange part and the cylindrical support member becomes large, and a stable connection structure with little backlash can be obtained.

  Further, in the present invention, when the wafer holder, the flange part, and the cylindrical support member are configured as separate parts, and the conventional cylindrical support body is joined by screwing each part Compared to the above, the heat treatment accompanying the bonding can be eliminated, and the cost can be reduced. Further, when the cylindrical support member is joined, the wafer holding surface needs to be reworked because the wafer holding body is slightly deformed. Since such heat treatment is not performed, there is no need for reworking and cost reduction can be achieved.

  In addition, since the support structure of the present invention is superior in heat uniformity and reliability as compared with the conventional structure as described above, it can be suitably used in a semiconductor manufacturing apparatus, inspection apparatus, or the like.

[Example 1]
As the wafer holder, an aluminum nitride (AlN) wafer holder was fabricated. First, 0.5% by weight of Y ₂ O ₃ as a sintering aid was added to the AlN powder, an organic solvent and a binder were further added, and mixed by ball mill mixing for 24 hours. Granules were produced from the obtained slurry by spray drying, and the granules were molded by a press method to produce a molded body. The obtained molded body was degreased at 800 ° C. in a nitrogen atmosphere, and then sintered at 1800 ° C. in a nitrogen atmosphere to obtain an AlN sintered body.

After the heating element is printed and fired using the W paste on the AlN sintered body, another AlN sintered body produced in the same manner as described above is stacked, and Al ₂ O ₃ -Y is sandwiched between the _two AlN sintered bodies. A wafer holder having a diameter of 330 mm and a thickness of 20 mm in which a heating element was embedded was obtained by applying a ₂ O ₃ -AlN-based bonding paste and applying pressure in one axial direction while heating in a nitrogen atmosphere. A counterbore hole reaching the heating element was formed on the wafer support, and a W electrode part for supplying power to the heating element was brazed.

  In addition, AlN powder was sintered in the same manner as described above to produce an AlN flange part having an outer diameter of 60 mm, a height of 20 mm, and a wall thickness of 3 mm. On the inner surface of the flange part, an internal thread having a groove inner diameter of 55 mm and a thread pitch of 1.5 mm was formed to rotate eight times. Further, in order to attach the flange part to the wafer holder, four M5 screw holes were formed in the bottom part having a diameter of 54 mm. This flange part was attached to a predetermined position of the wafer holder with a Ni-plated W screw. Then, a counterbore part having a diameter of 3 mm was formed so as to straddle the flange part and the head of the W screw, and a W anti-rotation pin having a diameter of 2.95 mm and plated with Ni was inserted therein.

  Next, the AlN powder is sintered in the same manner as described above to produce a cylindrical support member having an outer diameter of 55 mm and a wall thickness of 5 mm, and can be screwed into the female screw of the flange part. The male screw thread was formed on. Then, the flat surfaces of the cylindrical support member and the flange part were finished to have a flatness of 50 μm, and the cylindrical support member was screwed to the flat part of the flange part and screwed to be integrated.

  After that, on the side surface of the integrated cylindrical support member and flange part, the flange part is penetrated and counterbored so as to leave 2 mm out of the thickness of 5 mm of the cylindrical support member, and four horizontal holes with a diameter of 3 mm are formed. Formed. Furthermore, after forming a female screw from the flange part side in this horizontal hole, a non-rotating pin made of Mo is inserted inside, and the end face is sealed with a cap screw made of AlN, thereby completing the support structure of the wafer holder. did.

  A film was formed on a 12-inch silicon wafer using the wafer holder having the above support structure, but various insulating films and conductor films could be formed without any problem. Next, the temperature uniformity at 400 ° C. of the wafer holder was measured with a wafer thermometer, and as a result, good temperature uniformity was obtained with a variation of ± 2 ° C. Moreover, although the temperature was raised to a maximum of 800 ° C., the film formation was successfully performed.

Further, the support structure was subjected to a corrosion resistance test for 100 hours in a CF ₄ atmosphere, and the surface roughness of the flange part and the cylindrical support member before and after the experiment was measured. As a result, Ra was 0.7 μm before the experiment, but the flange part after the test was Ra = 0.9 μm, and the cylindrical support member Ra after the test was 0.8 μm.

[Example 2]
Although it is the same support structure as the said Example 1, the flange component and the cylindrical support member were formed with the mullite-alumina composite_body | complex. As a result of performing each experiment similar to the above on this support structure, it was possible to form a film without any problem, the thermal uniformity was 400 ° C. ± 1.7 ° C., and the surface roughness after the corrosion resistance test similar to the above was The flange part was Ra = 1.1 μm and the cylindrical support member was Ra = 0.9 μm.

[Example 3]
Although it is the same support structure as the said Example 1, the pitch of the thread of a flange part and a cylindrical support member was 3.0 mm. As a result, although there was some backlash, the film formation was not affected. Similarly, when the thread pitch of the flange part and the cylindrical support member is set to 5.0 mm, the film formation itself can be performed without any problem, but the backlash of the wafer holder increases, the wafer is transferred, and the lift pins are moved up and down. Occasionally, troubles such as the lift pins getting stuck.

[Example 4]
Although the support structure is the same as that of the first embodiment, each experiment similar to the above was performed using a flange part screw as an internal thread having an inner diameter of 55 mm and a cylindrical support member as a male screw. As a result, good film formation was possible from 400 ° C. to 700 ° C., but it was found that when the film was formed at 800 ° C., a small crack occurred at the tip of the thread of the cylindrical support member. It was.

[Example 5]
It is the same support structure as in Example 1, but the thermal expansion coefficient of 4.8 × ^{10 -6} / K with respect to AlN made of wafer holder, the thermal expansion coefficient of 2.8 × ^{10 -6} / K A flange part and a cylindrical support member made of silicon nitride (Si ₃ N ₄ ) were used. The support structure was heated to 800 ° C. in the same manner as described above, but no damage or the like occurred in the cylindrical support member, the flange component, or the wafer holder.

Furthermore, the same support structure as in Example 1 above, but with respect to the wafer holder made of AlN, a flange part made of alumina (Al ₂ O ₃ ) having a thermal expansion coefficient of 6.8 × 10 ⁻⁶ / K and A cylindrical support member was used. About this support structure, although it heated up to 800 degreeC similarly to the above, each component did not break.

However, with the same support structure as in Example 1, the same experiment was performed by screwing the Al ₂ O ₃ flange part and the cylindrical support member to the Si ₃ N ₄ wafer holder. As a result, when the temperature was raised to 600 ° C., a crack occurred in the flange part screwed to the wafer holder.

Moreover, although it is the same support structure as the said Example 1, the flange part and cylindrical support body whose thermal expansion coefficient is 3.8 * 10 < ^-6 > / K were used for the wafer holder made from AlN. About this support structure, although it heated up to 800 degreeC similarly to the above, each component did not break.

[Example 6]
Although it is the same support structure as the said Example 1, the flatness of each butt | matching plane part of a wafer holder, a flange component, and a cylindrical support member was set to 0.1 mm, 0.2 mm, and 0.3 mm. As a result of conducting each experiment similar to the above for these support structures, those having a flatness of 0.1 mm and 0.2 mm were free of backlash and good film formation was possible. On the other hand, when the flatness was 0.3 mm, the contact was not uniform and the backlash was large, so that good film formation was not possible.

  Further, when the temperature of the wafer at the upper part of the abutting portion between the wafer holder and the flange part, that is, the temperature distribution at 400 ° C. at a position 60 mm in diameter from the center of the wafer, the one having a flatness of 0.1 mm is ± 0. It was found that the one with .5 ° C. and the flatness of 0.2 mm was ± 0.7 ° C., whereas the one with the flatness of 0.3 mm was greatly reduced to ± 1.3 ° C.

[Example 7]
Although it was the same support structure as the said Example 1, when the outer diameter of the cylindrical support member was 30 mm and the same experiment as the above was conducted, the favorable result was obtained. However, when the flange part and the cylindrical support member had an outer diameter of 20 mm, the respective parts could not be fixed stably, and some backlash occurred. For this reason, the thickness variation of the film formed on the wafer is larger than that of the outer diameter of 30 mm.

[Example 8]
An AlN substrate was prepared in the same manner as in Example 1, and a heating element was formed on one side with W paste. Thereafter, 1.0% by weight of Y ₂ O ₃ powder was added to the AlN powder, and terpineol and ethyl cellulose were added to prepare an AlN paste. This was applied onto a substrate by a screen printing method, degreased in a nitrogen atmosphere, and then baked at 1830 ° C. in a nitrogen atmosphere. On top of this, similar to Example 1 above, a flange part made of AlN and a cylindrical support were attached to the holder, and the same evaluation as in Example 1 was performed. As a result, good results were obtained.

[Comparative Example 1]
It is the same support structure as in Example 1, but the flange part and the wafer holder with the _{Al 2 O 3 -Y 2 O 3} -AlN based bonding paste, and joined at 1800 ° C. while applying a load. As a result of performing a film formation test on this support structure in the same manner as described above, the film formation was possible without any problem, but the temperature uniformity of the wafer became ± 3.0 ° C. at 400 ° C., and the temperature near the flange part joint decreased. I found out that

[Comparative Example 2]
Without using flange parts, the same AlN wafer holder and cylindrical support member as in Example 1 were directly bonded using an Al ₂ O ₃ —Y ₂ O ₃ —AlN bonding paste. As a result of performing each test on the support structure in the same manner as described above, the heat uniformity at 400 ° C. was ± 4.1 ° C., and the temperature at the center was the lowest. When an attempt was made to raise the temperature to 800 ° C. in this state, the wafer holder was damaged from the vicinity of the joint when the temperature exceeded 780 ° C.

It is a schematic sectional drawing which shows one specific example of the connection structure by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wafer holding body 2 Flange parts 3 Cylindrical support member 4 Screw 5 Non-rotating pin 6 Cap screw

Claims (12)

  A support structure for supporting a wafer holder, in which an electric circuit is embedded in a ceramic sintered body or on a surface thereof, with a cylindrical support member, the flange part having a thread formed on the wafer holder, A support structure for a wafer holder, wherein a thread provided on a cylindrical support member is screwed to a thread of a flange part.   2. The wafer holder supporting structure according to claim 1, wherein the flange part is screwed to the wafer holder with a plurality of screws.   The support structure for a wafer holder according to claim 2, wherein a screw for screwing the flange part to the wafer holder is attached to the inside of the flange part. 4. The wafer according to claim 1, wherein a difference in thermal expansion coefficient between the wafer holder, the flange component, and the cylindrical support member is 2.0 × 10 ⁻⁶ / K or less. 5. Support structure for holding body. 3. The difference in thermal expansion coefficient between the screw for fixing the flange part to the wafer holder and the flange part and the wafer holder is 2.0 × 10 ⁻⁶ / K or less. Support structure for wafer holder.   6. The support structure for a wafer holder according to claim 1, wherein the material of the wafer holder is aluminum nitride.   The material of the flange part and the cylindrical support member is any one of aluminum nitride, mullite-alumina composite, silicon carbide, silicon nitride, and alumina, according to any one of claims 1 to 6. Support structure for wafer holder.   The wafer holder and the flange part are abutted at the plane part, and the flange part and the cylindrical support member are abutted at the plane part, and the flatness of each abutted plane part is 0.2 mm or less. The support structure for a wafer holder according to claim 1, wherein:   9. A wafer holding device according to claim 1, wherein the cylindrical support member screwed into the flange part is fixed by a detent pin inserted from a lateral hole provided in the flange part. Body support structure.   The pitch of the thread of the screw which mutually engages with the flange part and the cylindrical support member is 3 mm or less, and the diameter of the screw is 30 mm or more. The support structure of the wafer holder as described.   11. The wafer holding according to claim 1, wherein the flange part and the screw thread provided on the cylindrical support member are a female screw and the cylindrical support member are male threads. Body support structure.   12. The semiconductor manufacturing apparatus according to claim 1, wherein the support structure for supporting the wafer holder with a cylindrical support member is the support structure according to claim 1.

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