JP2010186765A - Wafer supporter for wafer prober and wafer prober carrying the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wafer supporter for a prober having a light weight and high rigidity, causing a small deformation during heating-up or cooling-down thereof, excellent in temperature uniformity and rapid elevation or lowering of the temperature, which can reproduce a high-precision measurement even when it is repeatedly used. <P>SOLUTION: This wafer supporter is a wafer supporter 1 for a wafer prober comprising: a chuck top 10 having a wafer placing face; a temperature controlling means 20 provided on a face of the chuck top 10 opposite to the wafer placing face; and a warpage preventing plate 30 provided on a face of the temperature controlling means 20 opposite to a counter face to the chuck top 10, in which under the warpage preventing plate 30, a supporter 50 having a cavity 60 is provided and the difference in the thermal expansion coefficient between the warpage preventing plate 30 and the chuck top 10 is a predetermined value or less. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wafer holder used in a wafer prober for inspecting electrical characteristics of a semiconductor wafer placed on a wafer placement surface, and a wafer prober on which the wafer holder is placed.

  2. Description of the Related Art Conventionally, in a semiconductor inspection process, burn-in is performed on a semiconductor substrate (wafer) to prevent occurrence of defects after shipment. In this burn-in, the wafer on which the semiconductor circuit is formed is heated to a temperature higher than the normal use temperature before being cut into individual chips, and semiconductor chips that are likely to become defective are accelerated and defective. Measure the electrical performance and remove defective products. In this burn-in process, reduction of processing time is strongly demanded in order to improve throughput.

  By the way, a heater for holding and heating the wafer is used in the burn-in process, but a conventional heater is made of metal because the entire back surface of the wafer needs to be in contact with the ground electrode. It was. A wafer having a circuit formed thereon is placed on the metal flat plate heater, and a probe called a probe card having a large number of electrode pins (probe pins) for energization is placed on the metal plate heater from several tens kgf to several hundred kgf. The electrical characteristics of the chip were measured by pressing with force.

  At this time, if the heater is thin, the heater is deformed, and a contact failure may occur between the wafer and the probe pin. Therefore, in order to maintain the rigidity of the heater, it is necessary to use a thick metal plate having a thickness of 15 mm or more. As a result, the heat capacity increases and it takes a long time to raise and lower the heater, which is a great obstacle to improving the throughput. It was.

  In the burn-in process, electricity is passed through the chip to measure the electrical characteristics. With the recent increase in chip output, the chip generates a lot of heat when measuring the electrical characteristics, and in some cases, the chip self-heats. Since it may break down, it is required to cool rapidly after the measurement. In addition, it is required to be as uniform as possible during the measurement. Therefore, copper (Cu) having a high thermal conductivity of 403 W / mK has been used as the material of the metal plate.

  On the other hand, in Patent Document 1, instead of a thick metal plate, a thin, hard and hard-to-deform ceramic substrate is used, and by forming a thin metal layer on the surface, a wafer prober that is difficult to deform and has a small heat capacity is obtained. Techniques for manufacturing have been proposed. According to Patent Document 1, since the rigidity is high, poor contact is unlikely to occur, and since the heat capacity is small, the temperature can be raised and lowered in a short time. And it is supposed that an aluminum alloy, stainless steel, etc. can be used as a support stand for installing a wafer prober.

  However, as described in Patent Document 1, if the wafer prober is supported only at its outermost periphery, the wafer prober may be warped by pressing the probe card. Met.

  Furthermore, in recent years, with the miniaturization of semiconductor processes, the load per unit area during probing increases, and high accuracy is required for alignment between the probe card and the wafer prober. The wafer prober normally repeats the operation of heating the wafer to a predetermined temperature, moving to a predetermined position during probing, and pressing the probe card. Therefore, high accuracy of the alignment is also required for the drive system used to move the wafer prober to a predetermined position.

  However, in the conventional wafer prober, when the wafer held on the chuck top is heated to a predetermined temperature, that is, a temperature of about 100 to 200 ° C., the heat is transferred to the drive system, and the metal parts of the drive system are thermally expanded. As a result, there is a problem that accuracy is impaired. Furthermore, due to an increase in load during probing, the rigidity of the wafer prober itself on which the wafer is placed has been required. If the chuck top itself is deformed by a load during probing due to insufficient rigidity, the probe pins of the probe card cannot be uniformly contacted with the wafer and cannot be inspected, and in the worst case, the wafer may be damaged.

  If the prober is increased in size, the deformation of the wafer prober can be suppressed to some extent, but the weight of the prober itself increases, and there is a problem that this increase in weight adversely affects the accuracy of the drive system. In addition, with the increase in size of the wafer prober, there has been a problem that the temperature rise and cooling time of the wafer prober becomes very long and the throughput is lowered.

  Further, a cooling mechanism is often provided in order to increase the temperature raising / lowering speed of the wafer prober and improve the throughput. However, conventionally, as disclosed in Patent Document 1, for example, the cooling mechanism is air-cooled, or a metal cooling plate is provided directly below the metal heater. In the former case, there is a problem that the cooling rate is slow because of air cooling. Even in the latter case, since the cooling plate is made of metal, there is a problem that the probe plate is easily deformed when the probe card pressure is directly applied to the cooling plate during probing.

JP 2001-033484 A

  In order to solve these problems, Patent Document 1 employs a technique of using ceramics for the chuck top. However, when the chuck top is made of ceramics, when the wafer is heated to a predetermined temperature, that is, a temperature of about 100 to 200 ° C., a load is applied to the chuck top due to a difference in thermal expansion between the chuck top and the support that supports the wafer. As a result, cracks may occur exceeding the breaking strength of the chuck top itself, or the probe pins may not be able to contact the wafer uniformly and inspection may not be possible. In the worst case, the wafer may be damaged.

  Japanese Patent Laid-Open No. 2001-135681 proposes a method for preventing warping and cracking of a ceramic chuck top by providing a large number of support columns in a bottomed cylindrical support container. It is described that these support columns are preferably arranged in a grid pattern at intervals of 1 to 10 mm, and are preferably supported at a number of locations.

  However, when supporting by a large number of support pillars, heat easily flows into the support container from the chuck top heated to a temperature of about 100 to 200 ° C. via the support pillar, and the support container warps due to the inflowed heat. Therefore, the problem of chuck top warping has not been solved. Although it is conceivable to interpose a heat insulating material as a countermeasure against the inflow of heat, it is not possible to insulate effectively with metal, and there is a concern that the rigidity of resin or the like may decrease. In addition, a high-accuracy heat insulating material with a tolerance of 1 to 2 μm is required for a large number of support pillars and support containers. However, since it is difficult to control the flatness of the heat insulating material, it is extremely expensive. In addition, the assembly itself is expected to be difficult.

  On the other hand, in Japanese Patent No. 3945527, by providing a gap between the chuck top and the support body, the heat insulation effect is enhanced without impairing the high rigidity, thereby improving the alignment accuracy and heat uniformity. Furthermore, a wafer holder for a wafer prober capable of rapidly raising and cooling the chip is disclosed. However, the demand for high accuracy on the top surface of the chuck top has been increasing due to the recent progress in miniaturization of wiring, and the chuck top itself has warped due to the temperature distribution in the thickness direction of the chuck top during temperature rise and cooling. The problem that the accuracy of the flatness of the upper surface of the chuck top at room temperature cannot be maintained at the time of temperature rise or cooling cannot be ignored.

  The present invention has been made to solve the above problems. That is, according to the present invention, the flatness of the upper surface of the chuck top with high accuracy at normal temperature can be maintained with high accuracy not only at normal temperature but also at the time of heating or cooling. Damage can be prevented, high-accuracy temperature distribution can be achieved even during temperature rise and cooling, and the lightweight and highly heat-insulating structure reduces the load on the lower drive system and blocks heat inflow. An object of the present invention is to provide a wafer holder for a wafer prober that can realize accurate probing and can reproduce accurate measurements even when used repeatedly, and a wafer prober apparatus equipped with the wafer holder.

  In order to achieve the above object, a wafer holder for a wafer prober provided by the present invention includes a chuck top having a wafer mounting surface, and temperature control means installed on the chuck top on the surface opposite to the wafer mounting surface. And a warpage preventing plate installed on the surface opposite to the surface facing the chuck top in the temperature control means, and a support having a gap is provided below the warpage preventing plate, The thermal expansion coefficient difference between the warpage prevention plate and the chuck top is not more than a predetermined value.

  Further, the wafer holder for a wafer prober provided by the present invention has a chuck top having a wafer placement surface, and a warp prevention plate installed on the chuck top on the surface opposite to the wafer placement surface, A support having a gap is provided at a lower portion of the warpage prevention plate, and a storage portion is provided between the chuck top and the warpage prevention plate, and the storage portion includes a temperature control means. The thermal expansion coefficient difference between the warpage preventing plate and the chuck top is not more than a predetermined value.

  In the wafer holder for a wafer prober of the present invention, it is preferable that a first support member is provided between the chuck top and the warp prevention plate. Moreover, a 1st ring-shaped member may be provided as this 1st support member, and the said accommodating part may be formed inside this 1st ring-shaped member.

  In the wafer holder for a wafer prober according to the present invention, the support is disposed on the bottom substrate, and the second support member and / or the chuck top disposed on the bottom substrate and supporting the warpage prevention plate. It is preferable to consist of a 3rd support member. The second support member can be composed of a plurality of second support columns and a second ring-shaped member.

  The wafer holder for a wafer prober of the present invention can be provided in a temperature control unit for a wafer prober. Further, this temperature control unit can be provided in a wafer prober.

  According to the present invention, it is lightweight and has high rigidity, the chuck top hardly deforms due to warping during temperature rise or cooling, is excellent in heat uniformity and rapid temperature rise and fall, and is highly accurate even after repeated use. Can be provided, a prober temperature control unit equipped with the prober wafer holder, and a wafer prober equipped with the prober temperature control unit.

1 is a schematic sectional elevation view showing a specific example of a wafer holder for a wafer prober according to the present invention. It is a cross-sectional elevation view showing another support mode of the chuck top shown in FIG. FIG. 10 is a sectional elevation view showing still another support mode of the chuck top shown in FIG. 1. FIG. 10 is a sectional elevation view showing still another support mode of the chuck top shown in FIG. 1. It is a schematic top view which shows the example of arrangement | positioning of the 1st supporting member which the wafer holder for wafer probers by this invention has suitably. It is a general | schematic cross-section elevation which shows the other specific example of the wafer holder for wafer probers by this invention. It is a general | schematic cross-sectional elevation view which shows the specific example of the 2nd supporting member with which the wafer holder for wafer probers by this invention has suitably. FIG. 6 is a schematic sectional elevation view showing still another specific example of a wafer holder for a wafer prober according to the present invention. It is a schematic top view which shows one specific example of the fastening method of the 2nd ring-shaped member with which the wafer holder for wafer probers by this invention has suitably. FIG. 6 is a schematic sectional elevation view showing still another specific example of a wafer holder for a wafer prober according to the present invention. It is a schematic sectional elevation view showing a specific example of the temperature control means of the wafer holder for a wafer prober according to the present invention. It is a general | schematic fragmentary sectional elevational view which shows the specific example of the 1st and 3rd supporting member which the wafer holder for wafer probers by this invention has suitably.

  One embodiment of a wafer holder for a wafer prober according to the present invention includes a chuck top having a wafer placement surface, temperature control means installed on the chuck top opposite to the wafer placement surface, and a chuck in the temperature control means. It has a warpage prevention plate installed on the surface opposite to the surface facing the top, and the thermal expansion coefficient difference between the warpage prevention plate and the chuck top is not more than a predetermined value.

  Thereby, when measuring the electrical characteristics of the semiconductor device formed on the wafer in a temperature range from a low temperature of −several tens of degrees Celsius to a high temperature of 150 to 200 degrees Celsius, for example, the chuck top and the chuck top attached to the chuck top, for example It can prevent deformation of the chuck top due to warpage caused by differences in thermal expansion with each member of temperature control means such as metal cooling modules and heaters, and achieves high-accuracy probing in the above temperature range, the same as normal temperature it can.

  The wafer prober for a wafer prober according to the present invention has high rigidity since the warp prevention plate is provided on the chuck top having the wafer mounting surface. By using a highly rigid material for these, deformation of the chuck top due to pressing during probing can be further suppressed, and high-precision measurement can be reproduced even when used repeatedly.

  A first support member is preferably provided between the chuck top and the warp prevention plate. The first support member may be a ring-shaped member or a support column. By providing a through hole or a counterbore on the surface in contact with the chuck top, heat insulation can be enhanced, and high rigidity and high heat insulation can be achieved by appropriately controlling the contact area. When more importance is attached to rigidity, it is preferable to support the outer edge portion of the chuck top with a ring-shaped member, and desired rigidity can be obtained by appropriately combining the ring-shaped member and / or a plurality of support columns.

  A support having a gap is provided below the warpage prevention plate. Due to the heat insulating effect of the gap, the heat of the wafer, which becomes a high temperature of 150 to 200 ° C. or a low temperature of −several tens of ° C. during probing, is transmitted to the drive system located further below through the warp prevention plate and the support. Can be effectively suppressed. As a result, the temperature difference between the warpage preventing plate and the support can be reduced, and deformation of the chuck top can be suppressed. Furthermore, the temperature rise at the time of temperature rise in the drive system and the temperature drop at the time of cooling can be reduced to suppress deterioration in accuracy of the drive system.

  The support body is preferably composed of a bottom substrate and a second support member that is installed on the bottom substrate and supports the warp prevention plate. These members may be integrated, but are in a separable contact. More preferably. By adopting such a structure, it is possible to provide a contact interface serving as a thermal resistance between the warp prevention plate and the second support member and between the second support member and the bottom substrate, and from the chuck top to the drive system. The heat insulation effect can be further increased. As a result, the deformation of the chuck top can be prevented, the amount of heat transfer in the drive system can be reduced, and the increase in temperature of the drive system can be suppressed to further suppress deterioration in accuracy.

  The shape of the second support member is preferably a columnar shape or a ring shape, and may be a combination thereof. High rigidity and high heat insulation can be achieved by appropriately controlling the location of the second support member that partially supports the warpage prevention plate and the contact area thereof. Further, the warpage preventing plate and the bottom substrate may be fastened via the second support member. As a result, compared to the conventional case where the chuck top and the bottom substrate are directly fastened, the temperature difference of the fastening portion can be reduced, so that the difference in thermal expansion can be reduced, and deformation of the chuck top can be prevented.

  Furthermore, by adopting a ring-shaped member as the second support member, not only can rigidity be improved, but also by shifting the fastening position of the warpage prevention plate and the ring-shaped member and the fastening position of the bottom substrate and the ring-shaped member, The ring-shaped member can serve as a stress relaxation layer, can reduce warping at high temperatures and low temperatures compared to the case of using only support columns, and can realize highly accurate measurement.

  Further, another embodiment of the wafer holder for a wafer prober of the present invention includes a chuck top having a wafer mounting surface, and a warp preventing plate installed on the chuck top opposite to the wafer mounting surface. A storage portion is provided between the warp prevention plate and the chuck top, and temperature control means is disposed in the storage portion. Thereby, it is possible to support a highly rigid chuck top without using a temperature control means that is often made of metal, and it is possible to increase the rigidity as compared with the case where it is supported only through the temperature control means, Deformation of the chuck top can be suppressed.

  Next, a specific example of the wafer holder for a wafer prober of the present invention will be described with reference to the drawings. FIG. 1 shows a specific example of a wafer holder for a wafer prober according to the present invention. The wafer prober wafer holder 1 includes a chuck top 10 having a wafer placement surface 10a, a temperature control means 20 installed on a surface of the chuck top 10 opposite to the wafer placement surface 10a, and a temperature control means. 20 includes a warpage preventing plate 30 disposed on a surface opposite to the surface facing the chuck top 10.

  The difference in thermal expansion coefficient between the warp prevention plate 30 and the chuck top 10 is not more than a predetermined value. Thereby, even if the temperature of the wafer prober wafer holder 1 is changed to a high temperature or a low temperature by the temperature control means 20, deformation due to warping of the chuck top 10 hardly occurs.

  That is, the chuck top 10 may be heated to a high temperature by the temperature control means 20 by sandwiching the temperature control means 20 between the chuck top 10 and the warp prevention plate 30 whose difference in thermal expansion coefficient is a predetermined value or less. On the contrary, even when cooled to a low temperature, the amount of thermal expansion of the chuck top 10 and the warpage preventing plate 30 can be made substantially the same and balanced. Thereby, the deformation amount of the chuck top 10 due to the temperature change can be reduced as compared with the case where there is no warpage prevention plate 30 or the case where the thermal expansion coefficients of the warpage prevention plate 30 and the chuck top 10 are greatly separated.

  The flatness of the wafer mounting surface 10a of the chuck top 10 is preferably 10 μm or less. If this value exceeds 10 μm, the probe pin at the time of probing will not be able to evaluate properly due to contact with the probe pin, or it may be erroneously determined as a defective product due to poor contact and the yield will be evaluated worse than necessary. Sometimes. Moreover, it is preferable that the parallelism between the wafer mounting surface 10a of the chuck top 10 and the bottom surface of the support described later is 10 μm or less. If this value exceeds 10 μm, contact failure may occur as described above.

  The flatness of a surface means the distance when assuming the shortest distance between two parallel surfaces sandwiching the surface. The parallelism of two surfaces means that when the other surface is sandwiched between two geometric planes parallel to one surface (reference plane), the distance between these two geometric planes is minimized. That interval.

  Even when the flatness of the wafer mounting surface 10a of the chuck top 10 and the parallelism between this and the bottom surface of the support are good at 10 μm or less at room temperature, these flatness and parallelism are, for example, when probing at 200 ° C. If it exceeds 10 μm, it is not preferable as described above. The same applies to probing at −60 ° C., for example. That is, both flatness and parallelism need to be 10 μm or less over the entire temperature range for probing.

For example, when the thermal expansion coefficient of the warp prevention plate 30 is 5 × 10 ⁻⁶ / K larger than the chuck top 10, when the temperature is raised to 100 to 200 ° C., the temperature control means 20 is provided below the chuck top 10. Since the thermal expansion amount of the warpage preventing plate 30 to be arranged is larger than that of the chuck top 10, stress is applied to the chuck top 10 so that the wafer mounting surface 10 a is bent in a concave shape due to the bimetal effect, and the wafer of the chuck top 10 is The flatness of the mounting surface 10a is deteriorated.

  Thus, even when the flatness of the wafer mounting surface 10a of the chuck top 10 and the parallelism between it and the bottom surface of the support are good at 10 μm or less at room temperature, probing when the temperature is raised to 100 to 200 ° C. Sometimes, these flatness and parallelism exceed 10 μm, which is not preferable. Further, when a support member is disposed at the center of the chuck top 10, the support member pushes up the center of the chuck top 10 deformed into a concave shape, and if it is severe, the chuck top 10 is damaged. Probing may not be continued.

  Conversely, when cooled to −60 ° C., the warpage preventing plate 30 shrinks and becomes smaller than the chuck top 10, and therefore stress that causes the wafer mounting surface 10 a to bend in a convex shape on the chuck top 10. As a result, the flatness of the wafer mounting surface 10a of the chuck top 10 deteriorates. As described above, even when the flatness of the wafer mounting surface 10a of the chuck top 10 and the parallelism between the chuck mounting surface 10a and the bottom surface of the support are good at 10 μm or less at the room temperature, these are at the time of probing when cooled to −60 ° C. It is not preferable that the flatness and the parallelism exceed 10 μm.

The difference in thermal expansion coefficient between the warp prevention plate 30 and the chuck top 10 is preferably 5 × 10 ⁻⁶ / K or less, and more preferably substantially the same. In particular, when the probing temperature is in the range of −60 to 200 ° C., the difference in coefficient of thermal expansion between the chuck top 10 and the warpage preventing plate 30 is preferably 2 × 10 ⁻⁶ / K or less. Within this range, the flatness and parallelism described above can be set to 10 μm or less over the entire temperature range in which probing is performed.

Of course, when the temperature range at the time of probing is wider than the above range, the difference in thermal expansion coefficient between the chuck top 10 and the warp preventing plate 30 needs to be made smaller, and conversely the temperature range at the time of probing. If it is narrow, it may be larger than the thermal expansion coefficient difference. According to the examination results of the present inventors, 2 × 10 ⁻⁶ / K or less is preferable in consideration of the general operating temperature range of the wafer prober.

  Further, as shown in FIG. 2A, a countersunk hole is provided on the surface of the chuck top 10 on the side facing the warp prevention plate 30, leaving an outer edge part, and the temperature control means 20 is provided in the storage part made of the countersunk hole. And the temperature control means 20 can be held between the chuck top 10 and the warpage preventing plate 30.

  At this time, similarly to the above, the temperature control means 20 changes the wafer prober wafer holder 1 to a high temperature or a low temperature by setting the difference in thermal expansion coefficient between the warp preventing plate 30 and the chuck top 10 to a predetermined value or less. It is possible to suppress the deformation of the chuck top 10 at the time of being applied. Further, since the outer edge portion of the chuck top 10 is supported by the flat plate portion of the chuck top 10 having high rigidity and the warp prevention plate 30 having high rigidity, the chuck top 10 is supported by the temperature control means 20. High rigidity can be obtained.

  As shown in FIG. 2B, the storage portion into which the temperature control means 20 is fitted is provided with a counterbore hole on the side of the warp prevention plate 30 facing the chuck top 10, and the temperature control means 20 is fitted into the flat plate shape. It may be held between the chuck top 10 and, as shown in FIG. 2C, both the side of the chuck top 10 that faces the warp prevention plate 30 and the side of the warp prevention plate 30 that faces the chuck top 10. A counterbore hole may be provided, and the temperature control means 20 may be fitted into these counterbore holes.

  Further, the first support member 40 may be provided between the chuck top 10 and the warp prevention plate 30. For example, as shown in FIG. 3, by providing a ring-shaped first support member 40a, the temperature control means 20 can be fitted with the inside of the first ring-shaped member 40a as a storage portion. At this time, as in the case described above, the difference in thermal expansion coefficient between the warpage preventing plate 30 and the chuck top 10 is set to a predetermined value or less so that the temperature control means 20 causes the wafer prober wafer holder 1 to be heated at a high temperature or a low temperature. It is possible to reduce the deformation of the chuck top 10 when changed to, and to increase the rigidity. Furthermore, since the contact interface between the chuck top 10 and the warp preventing plate 30 can be increased, heat escape from the outer edge of the chuck top 10 can be mitigated, and compared with the case shown in FIG. Thermal property can be improved.

  As shown in FIG. 4, a plurality of first support columns 40 b may be provided as the first support member 40. As a result, the rigidity can be increased, and since it is not necessary to support the outer edge portion of the chuck top 10, heat escape from the outer edge portion of the chuck top 10 can be reduced. Furthermore, since the temperature control means 20 can be disposed up to the outer edge portion, it is possible to improve heat uniformity as compared with the structure shown in FIGS. 2 to 4, the temperature control means 20 is sandwiched between the chuck top 10 and the warpage prevention plate 30, so that the heat from the temperature control means 20 is transmitted equally to the chuck top 10 and the warpage prevention plate 30. In addition, the temperature control means 20 does not have to directly support the chuck top 10.

  As a result, the temperature control means 20 is affected by the stress of the fastening means 70 such as screws applied to the chuck top 10 and the warp prevention plate 30, or the stress from the probe pins received from the wafer mounting surface 10a of the chuck top 10 during probing. Not receive. Therefore, the temperature control means 20 can be made into an unloaded structure that does not consider these stresses. On the contrary, the chuck top 10 and the warpage preventing plate 30 can have a no-load structure that is not affected by stress due to thermal deformation of the temperature control means 20.

  As described above, the chuck top 10 and the warpage preventing plate 30 can be configured to have no load with respect to the temperature control means 20, so that the temperature control means 20 has a flatness of the wafer placement surface 10 a of the chuck top 10. By controlling only the difference in coefficient of thermal expansion between the chuck top 10 and the warp prevention plate 30, the flatness and parallelism of the wafer mounting surface 10a of the chuck top 10 at high and low temperatures can be avoided. Can be controlled.

  As shown in FIG. 5A, the plurality of first support columns 40 b that support the chuck top 10 are arranged in a circumferential direction on a circle concentric with the chuck top 10 in addition to the center of the chuck top 10. It is preferable to arrange them evenly. At this time, it is preferable that the diameter of the concentric circle is ½ or more of the diameter of the chuck top 10. If this value is less than ½, when the end of the chuck top 10 is pressed during probing, the amount of deformation (deflection amount) of the chuck top 10 exceeds an allowable amount, and proper probing cannot be performed. There is.

  As another arrangement example of the plurality of first support pillars 40b, as shown in FIG. 5B, the plurality of first support pillars 40b are arranged evenly in the circumferential direction on one concentric circle with respect to the chuck top 10. Also good. Further, as shown in FIG. 5C, a plurality of circles having diameters (R1, R2,...) Are equally distributed in the circumferential direction on each circle arranged concentrically with respect to the chuck top 10. It may be arranged in places. Further, as shown in FIG. 5 (d), one central portion may be arranged in addition to FIG. 5 (c).

  When arranged on a plurality of concentric circles, the diameter of the outermost circle is preferably 1/2 or more of the diameter of the chuck top 10 and more preferably 2/3 or more. If this diameter is less than ½ of the diameter of the chuck top 10, the amount of deformation (deflection) of the chuck top 10 exceeds the allowable amount when the probing pressing pressure on the outer periphery of the chuck top 10 becomes strong, as described above. This is because accurate probing cannot be performed.

  In addition, on the outermost circle, the first support pillars 40b are preferably arranged at three or more locations, and more preferably at six locations or more. If it is less than three places, the span between adjacent support columns becomes too wide, so that when the intermediate part of adjacent support columns is pressed during probing, the amount of deformation (deflection amount) of the chuck top 10 becomes large and appropriate. This is because proper probing may not be possible.

  The larger the number of first support members 40 is, the more advantageous is the bending due to pressing during probing, but if there are too many, the temperature control means 20 must have a large number of through holes for the first support member 40. Therefore, the soaking property may be lowered. Therefore, it is necessary to design appropriately from both the required rigidity and soaking characteristics. In general, the contact area between the chuck top 10 and the first support member 40 is preferably 20% or less of the area of the wafer placement surface 10 a of the chuck top 10. If it is this range, high rigidity can be maintained, without impairing soaking | uniform-heating property.

  Referring to FIG. 1 again, a support body 50 is provided at the lower part of the warpage preventing plate 30. The support body 50 includes a bottom substrate 51 and a second support member 52 that is provided on the bottom substrate 51 and supports the warp prevention plate 30. The second support member 52 preferably has a structure that supports the warpage preventing plate 30 only at a plurality of local portions. Thereby, the contact area between the warpage prevention plate 30 and the support 50 can be reduced, and the gap portion 60 can be easily formed between the warpage prevention plate 30 and the bottom substrate 51.

  Due to the gap 60, most of the space between the chuck top 10 and the bottom substrate 51 becomes an air layer, so that an efficient heat insulating structure can be obtained. The shape of the gap 60 is not particularly limited, as long as the heat generated by the temperature control means 20 and the cool air around the wafer prober wafer holder 1 can be effectively suppressed from being transmitted to the bottom substrate 51. Any shape is acceptable.

  The second support member 52 may be either integrated with the bottom substrate 51 or abutted so as to be separable, but is preferably abutted so as to be separable. This is because the contact between the warp prevention plate 3 and the second support member 52 and between the second support member 52 and the bottom substrate 51 is a contact interface, so that an effect as a thermal resistance can be expected.

  As described above, by efficiently insulating the heat transmitted from the chuck top 10 to the support body 50 and further to the lower portion of the support body 50, the temperature change amount of the support body 50 can be suppressed low, and the temperature change of the support body 50 can be suppressed. Therefore, the influence on the warp of the chuck top 10 can be reduced. Furthermore, since heat transfer to the drive system can be suppressed, deterioration in alignment accuracy during probing can be prevented, and high-precision probing can be realized.

  Although the 2nd support member 52 can be arbitrarily arrange | positioned suitably, it is preferable to arrange | position similarly to the 1st support pillar 40b. That is, the second support member 52 that supports the warp preventing plate 30 is circumferentially arranged on a circle concentric with the chuck top 10 in addition to the center of the chuck top 10 as shown in FIG. It is preferable to arrange them evenly. At this time, it is preferable that the diameter of the concentric circle is ½ or more of the diameter of the chuck top 10. If this value is less than ½, when the end of the chuck top 10 is pressed during probing, the amount of deformation (deflection amount) of the chuck top 10 exceeds the allowable amount, and proper probing may not be performed. There is.

  As another arrangement example of the second support member 52, as shown in FIG. 5B, a plurality of positions may be evenly arranged in the circumferential direction on one concentric circle with respect to the chuck top 10. . Further, as shown in FIG. 5C, a plurality of circles having diameters (R1, R2,...) Are equally distributed in the circumferential direction on each circle arranged concentrically with respect to the chuck top 10. It may be arranged in places. Further, as shown in FIG. 5 (d), one central portion may be arranged in addition to FIG. 5 (c).

  When arranged on a plurality of concentric circles, the diameter of the outermost circle is preferably 1/2 or more of the diameter of the chuck top 10 and more preferably 2/3 or more. If this diameter is less than ½ of the diameter of the chuck top 10, the amount of deformation (deflection) of the chuck top 10 exceeds the allowable amount when the probing pressing pressure on the outer periphery of the chuck top 10 becomes strong, as described above. This is because accurate probing cannot be performed.

  Moreover, it is preferable to arrange | position the 2nd supporting member 52 in 3 or more places on the outermost circle, and 6 or more places are especially preferable. If it is less than three places, the span between adjacent support columns becomes too wide, so that when the intermediate part of adjacent support columns is pressed during probing, the amount of deformation (deflection amount) of the chuck top 10 becomes large and appropriate. This is because proper probing may not be possible.

  The larger the number of the second support members 52 is, the more advantageous is the bending due to pressing during probing. However, when the number is too large, the contact area between the warpage preventing plate 30 and the second support member 52 becomes too large. When the temperature rises, the heat of the chuck top 10 is transmitted to the bottom substrate 51 of the support body 50 and further to the drive system via the second support member 52, and there is a possibility that the measurement accuracy is lowered and the probing cannot be continued. Accordingly, the contact area between the warp prevention plate 30 and the second support member 52 is preferably 20% or less of the area of the surface of the warp prevention plate 30 facing the bottom substrate 51. Within this range, the amount of heat transfer is limited and high accuracy can be maintained.

  Among the above, in particular, the second support member 52 is preferably provided in the central portion and the outer peripheral portion of the bottom substrate 51. The second support member 52 supports the warp prevention plate 30 that supports the chuck top 10, and can suppress deformation of the chuck top 10 when the probe card is pressed against the chuck top 10.

  Further, as shown in FIG. 6, a third support member 53 that directly supports the chuck top 10 and the bottom substrate 51 may be provided only in the center portion thereof. Further, the chuck top 10 and the warpage preventing plate 30 are fastened at the outer peripheral portion of the chuck top 10 via the fastening means 70 inserted through the first support column 40b, and the second support member 52 is inserted at the inner peripheral portion. The warpage preventing plate 30 and the bottom substrate 51 may be fastened via the fastening means 70 that has been made. At this time, the outer peripheral portion of the chuck top 10 can be prevented from being fastened between the bottom substrate 51 and the chuck top 10 and between the bottom substrate 51 and the warp prevention plate 30.

  By this fastening method, the influence of warpage due to the difference in thermal expansion due to the temperature difference between the chuck top 10 and the bottom substrate 51 can be greatly reduced, and when the chuck top 10 and the bottom substrate 51 are directly supported and fixed. In comparison, the warp of the chuck top 10 at a high temperature and a low temperature can be suppressed to be small.

  In addition, the bottom substrate 51 and the chuck top 10 of the support 50 may be directly supported using a plurality of third support members 53. Although the rigidity can be strengthened by this, a hole through which the third support member 53 is inserted into the temperature control means 20 or the warp prevention plate 30 is compared with the case where the warp prevention plate 30 is supported using the second support member 52. The rigidity is slightly deteriorated due to the necessity of opening, and the degree of freedom in designing the heater pattern and the coolant channel pattern of the temperature control means 20 to be described later is limited, so that the heat uniformity at high and low temperatures is lowered. This supporting method will be described in detail later with reference to FIG.

  As described above, by configuring the second support member 52 so as to partially support the warpage prevention plate 30 locally, a hollow structure can be formed between the warpage prevention plate 30 and the bottom substrate 51. Compared to the case where a columnar support body having an outer diameter equivalent to the outer diameter of the chuck top, or a support body that supports the outer periphery of the chuck top in a ring shape, is provided. Since the weight can be reduced, it is excellent in rapid temperature rise and fall, and the throughput of the inspection process can be increased.

  The second support member 52 may support the warp preventing plate 30 by a plurality of second support columns 52a as shown in FIG. 7A, or the outer edge as shown in FIG. 7B. The warpage preventing plate 30 may be supported by the second ring-shaped member 52b disposed in the portion and the plurality of second support columns 52a disposed inside thereof. In the latter case, since the number of the second support pillars 52a can be reduced, the number of parts can be reduced and the rigidity can be increased as compared with the former case.

  As described above, when only the center portion of the chuck top 10 is supported by the third support member 53, as shown in FIG. 8, the chuck top 10 and the bottom substrate 51 are connected to the third support member 53 and its fastening means 70. The warp preventing plate 30 is directly tightened using the second ring-shaped member 52b and its fastening means 70a, b for the outer edge portion and the second support column 52a and its fastening means 70 for the inner peripheral portion. And the bottom substrate 51 may be fastened.

  When fastening the second ring-shaped member 52b to the warp preventing plate 30 and the bottom substrate 51, as shown in FIGS. 8 and 9, the fastening means 70a and b are connected to the warp preventing plate 30 in the circumferential direction of the second ring-shaped member 52b. And the bottom substrate 51 may be alternately fastened. As a result, the second ring-shaped member 52b functions as a stress relaxation layer, and the influence of warpage due to the difference in thermal expansion caused by the temperature difference between the chuck top 10 and the bottom substrate 51 can be greatly reduced. Compared to the case where 51 is directly supported and fixed, the warp of the chuck top 10 at a high temperature or a low temperature can be reduced.

  If there are gaps between the temperature control means 20 and the chuck top 10 and between the temperature control means 20 and the warp prevention plate 30, heat transfer is hindered, leading to a decrease in the heating rate and cooling rate. Deteriorates thermal properties. For this reason, it is preferable to dispose a heat-resistant high thermal conductive resin sheet between the chuck top 10 and the temperature control means 20 or between the temperature control means 20 and the warpage prevention plate 30. Thereby, mutual adhesiveness increases and the said problem can be solved. As the high thermal conductive resin sheet, for example, a silicone resin is preferable because it has elasticity, heat resistance, and electrical insulation.

  A filler having a role of enhancing the heat conduction of the resin can be dispersed in the resin of the high thermal conductive resin sheet. The filler material is not particularly limited as long as it does not react with the resin. For example, boron nitride, aluminum nitride, alumina, silica, or the like can be used.

  The warpage preventing plate 30 is preferably made of the same material (thermal expansion, thermal conductivity, Young's modulus) as the chuck top 10. As a matter of course, the same material has the same thermal expansion coefficient and does not cause a difference in thermal expansion, so that the chuck top 10 is less likely to warp even at high and low temperatures.

  The material of the warp preventing plate 30 may be a material different from that of the chuck top 10, but in this case, it is appropriately selected according to the thermal expansion coefficient of the material of the chuck top 10. If this condition is met, the material of the warp prevention plate 30 may be metal, ceramics, or a metal ceramic composite.

  The thickness of the warp prevention plate 30 is not particularly limited, but as described above, when the warp prevention plate 30 supports the chuck top 10 via the first ring-shaped member 40a or the plurality of first support columns 40b, As the thickness is increased, the rigidity can be increased. However, if the thickness is larger than that of the chuck top 10, the heat capacity increases, and the temperature raising / lowering speed decreases. Therefore, it is preferable to set an appropriate thickness according to the purpose and application. In this case, when the material of the warpage preventing plate 30 is different from that of the chuck top 10, the Young's modulus is preferably 100 GPa or more and 200 GPa or more in order to prevent deformation of the upper surface of the chuck top 10 due to a load during probing. More preferred.

  On the other hand, as described above, when the chuck top 10 and the bottom substrate 51 are fastened using the plurality of third support members 53 to prevent the warpage prevention plate 30 from being involved in the support of the chuck top 10, the warpage prevention is performed. Since the plate 30 does not contribute to the rigidity at the time of probing, it is not necessary to increase the thickness in order to ensure the rigidity, and it is sufficient if the thickness is sufficient to form a hole or a screw hole for avoiding the third support member 53.

  When the warpage prevention plate 30 is not involved in the support of the chuck top 10 as described above, the warpage prevention plate 30 can be made thinner as shown in FIG. 10, so that the heat capacity is reduced, and the temperature increase rate and temperature decrease rate can be increased. it can. Further, by using a material with low rigidity which is relatively easy to process, it can be manufactured at a relatively low cost. In this case, the Young's modulus of the warpage preventing plate 30 is not particularly limited, but is preferably 100 GPa or more. This is because if the Young's modulus is too low, dents and twists are generated due to the stress at the time of fastening with screws or the like, and the warp prevention plate 30 cannot function.

  The temperature control unit 20 includes a heating element and / or a cooling module, and the chuck top 10 is heated and / or cooled by the temperature control unit 20. In recent years, in probing a semiconductor wafer, the wafer is often heated to a temperature of 100 to 200 ° C. If the heat of the heating element for heating the chuck top 10 cannot be prevented from being transmitted to the support 50. Then, heat is transferred to the drive system provided at the lower part of the support 50, and the mechanical accuracy is shifted due to the difference in thermal expansion of each component constituting the drive system, and the flatness of the upper surface (wafer mounting surface 10a) of the chuck top 10 is increased. And cause the degree of parallelism to deteriorate significantly.

  On the other hand, since the support body 50 of this embodiment can support the chuck top 10 only with a plurality of local portions, the contact area between the chuck top 10 and the support body 50 can be reduced. Since the gap portion 60 is provided, the heat insulation effect is high and the flatness and parallelism are not significantly deteriorated.

  By the way, in the wafer holder described in Japanese Patent No. 3945527, when the ring-shaped member is used as the support, the outer diameter of the heating element and the cooling module needs to be smaller than the inner diameter of the ring-shaped member. These heating elements and cooling modules could not be made the same size as the chuck top. For this reason, at the time of temperature rise, the thermal drooping of the outer periphery is large and there is a limit to the improvement of the soaking characteristic. Even during cooling, the flow path of the refrigerant cannot be extended to the outer periphery of the chuck top, so there is a limit to the improvement of the soaking characteristic during cooling.

  On the other hand, in the structure of this embodiment, since the chuck top 10 can be supported locally, it is possible to mount a heating element or a cooling module having an outer diameter substantially the same size as the chuck top 10. For this reason, it is possible to provide excellent soaking characteristics while maintaining flatness and rigidity at the time of temperature rise and cooling.

  For example, as shown in FIG. 11A, the temperature control means 20 can include a heating element 21 having an outer diameter substantially the same size as the chuck top 10. In this case, it is preferable to have a structure in which the resistance heating element 21a is sandwiched between insulating sheets 21b such as mica or silicone resin, so that it is preferable. A metal material can be used for the resistance heating element 21a. For example, a metal foil made of nickel, stainless steel, silver, tungsten, molybdenum, nichrome, or an alloy of these metals can be used.

  Of these metals, stainless steel and nichrome are preferred. This is because when stainless steel or nichrome is processed into the shape of the resistance heating element 21a, the circuit pattern of the resistance heating element 21a can be formed with relatively high accuracy by a technique such as etching. In addition, it is relatively inexpensive and has oxidation resistance, so that it can withstand long-term use even when the use temperature is high.

  Further, the insulating sheet 21b sandwiching the resistance heating element 21a is not particularly limited as long as it is a heat resistant insulator. For example, mica, silicon resin, epoxy resin, phenol resin, etc. are mentioned as mentioned above. In addition, when the resistance heating element 21a is sandwiched between such insulating resins, a filler can be dispersed in the resin in order to transfer the heat generated in the resistance heating element 21a to the chuck top 10 more smoothly. The role of the filler dispersed in the resin is to increase the thermal conductivity of silicon resin, etc., and the material is not particularly limited as long as there is no reactivity with the resin. For example, boron nitride, aluminum nitride, alumina, silica Substances such as can be used.

  As shown in FIG. 11A, when the temperature control means 20 consisting only of the heating element 21 is attached to the chuck top 10, the heating element 21 is disposed between the chuck top 10 and the warp prevention plate 30, and the chuck top is arranged. 10 and the warpage preventing plate 30 can be fixed by mechanical means such as screwing.

  As shown in FIG. 11B, when the temperature control means 20 includes a cooling module 22, an antifreeze refrigerant separately cooled by a chiller (not shown) is supplied to the water channel 22a of the cooling module 22. By doing so, the chuck top 10 can be rapidly cooled. When the chuck top 10 is heated, the temperature is raised by the heating element 21 provided in the lower part of the cooling module 22.

  At this time, since the cooling module 22 can serve as a soaking plate, higher soaking can be achieved by using a highly heat conductive material such as Cu or Al for the cooling module 22. In addition, by monitoring the temperature using a thermocouple or platinum resistor embedded in the cooling module 22 or the chuck top 10, the amount of heat generated by the heating element 21 can be controlled while cooling, and fine temperature control during cooling can be performed. it can.

  When the temperature control means 20 has the structure shown in FIG. 11B, the cooling module 22 is installed adjacent to the surface of the chuck top 10 opposite to the wafer mounting surface 10a. A resistance heating element 21a having a structure sandwiched between insulating sheets 21b is disposed adjacent to the lower surface, and these can be sandwiched and fixed between the chuck top 10 and the warp prevention plate 30. At this time, a soft material 23 having deformability, heat resistance, and high thermal conductivity may be inserted between the surface of the chuck top 10 opposite to the wafer mounting surface 10 a and the cooling module 22. it can.

  For example, by inserting a soft material 23 such as Si resin, the flatness and warpage between the chuck top 10 and the cooling module 22 can be alleviated, and the contact area can be increased. As a result, the cooling capacity originally provided by the cooling module 22 can be sufficiently exhibited, so that the cooling rate can be increased.

  As another embodiment of the temperature control means 20, as shown in FIG. 11C, a resistance heating element having a structure in which the chuck top 10 is sandwiched by an insulating sheet 21b on the surface opposite to the wafer mounting surface 10a. In some cases, 21 a is installed, the cooling module 22 is arranged on the lower surface thereof, and these are sandwiched between the chuck top 10 and the warpage preventing plate 30.

  As another embodiment of the temperature control means 20, as shown in FIG. 11 (d), resistance heating elements 21a are installed on both the upper and lower sides of the cooling module 22, and these are connected to the chuck top 10 and the warp prevention plate 30. It may be pinched with. As a result, the temperature of each resistance heating element 21a can be individually controlled so that the temperature of the chuck top 10 and the warpage preventing plate 30 is substantially the same. Compared to the case shown in FIGS. 11B and 11C, the chuck top 10 having an extremely high accuracy in which the flatness of the upper surface of the chuck top 10 hardly changes when the chuck top 10 is heated or cooled. Can be provided.

  It is preferable to provide a metal layer (not shown) for shielding (shielding) electromagnetic waves between the heating element 21 for heating the chuck top 10 and the chuck top 10. This metal layer for electromagnetic wave shielding has a role of blocking noise that affects the probing of the wafer such as electromagnetic waves and electric fields generated by the heating element 21 and the like. Although this noise does not have a great influence on the measurement of normal electrical characteristics, it significantly affects the measurement of the high frequency characteristics of the wafer.

  The electromagnetic wave shielding metal layer is formed of, for example, a metal foil inserted between the heating element 21 and the chuck top 10 and needs to be insulated from the chuck top 10 and the heating element 21. Although there is no restriction | limiting in particular in the material of metal foil, Since the heat generating body 21 becomes the temperature of about 200 degreeC, foil, such as stainless steel, nickel, or aluminum, is preferable.

  When the chuck top 10 is an insulator, when the chuck top 10 is a conductor between the electromagnetic shielding metal layer and the chuck top conductor layer formed on the wafer mounting surface 10a of the chuck top 10, In addition, a capacitor on an electric circuit is formed between the chuck top 10 itself and the metal layer for electromagnetic wave shielding, and this capacitor component may affect as a noise when probing the wafer. Therefore, in order to reduce this noise, it is preferable to reduce the noise by forming an insulating layer (not shown) between the electromagnetic shielding metal layer and the chuck top 10.

  Furthermore, it is preferable to provide a guard electrode layer (not shown) between the chuck top 10 and the metal layer for electromagnetic wave shielding through an insulating layer. By connecting this guard electrode layer to a metal layer formed on the support 50 to be described later, it is possible to further reduce noise that affects the high frequency characteristics of the wafer. That is, by covering the whole of the heating element 21 and the support body 50 with a conductor, it is possible to reduce the influence of noise when measuring wafer characteristics at high frequencies. Further, the influence of noise can be further reduced by connecting the guard electrode layer to the metal layer provided on the support 50.

  When the first to third support members are formed of support columns, the outer diameter is not particularly limited, but the outer diameter is preferably 5 mm or more. When the outer diameter is less than 5 mm, the support effect is not sufficient, and the support member is easily deformed, which is not preferable. Moreover, it is preferable that an outer diameter is 20 mm or less. When the outer diameter exceeds 20 mm, the contact area increases and it becomes difficult to obtain a heat insulating effect.

  Further, when the cooling module 22 is provided, it is necessary to provide a hole for avoiding contact with the first and third support members in the cooling module 22. This hole preferably has an appropriate gap so that it does not come into contact with the support member when it expands or contracts when the temperature is raised or lowered. If this gap is not sufficient, the support member comes into contact with the cooling module 22 and is cooled. It causes the speed to be lost and the flatness to be deteriorated.

  There are no particular restrictions on the method of fixing the first to third support members so that they can be separated from the bottom substrate 51 or the warp prevention plate 30, but brazing with active metal, glassing, screwing, etc. can be used. . Among these, screwing is particularly preferable. By screwing, it becomes easy to attach and detach, and further, since heat treatment is not performed at the time of fixing, deformation of the bottom substrate 51 or the warpage preventing plate 30 and the support member due to heat treatment can be suppressed.

  When the first to third support members are formed of support pillars, the shape is not particularly limited, and may be a rod-like body, a cone shape, a pyramid shape, or a cylindrical body. . In the case of a cylindrical body, as shown in FIG. 12, extra processing is applied to the temperature control means 20 such as the cooling module 22 and the heating element 21 by inserting fastening means 70 such as screws inside the cylindrical body A. This is particularly preferable because the chuck top 10 and the bottom substrate 51 or the warpage preventing plate 30 can be fixed without being applied.

  12A shows the case where the shape of the first support column 40b is a cylindrical body A, and FIG. 12B shows the case where the shape of the third support member 53 is the cylindrical body A. Shows the case. The first support column 40b or the third support member 53 is preferably in contact with the bottom substrate 51 or the warp prevention plate 30 in a separable manner. By making contact in a separable manner, the contact interface can be increased to further improve the heat insulation, and the chuck top 10 and the bottom substrate 51 or the warpage preventing plate 30 can be expanded and contracted independently, which adversely affects the flatness of the chuck top 10. It is because it becomes difficult to exert.

  The Young's modulus of the bottom substrate 51 is preferably 200 GPa or more. When the Young's modulus of the bottom substrate 51 is less than 200 GPa, since the thickness of the bottom substrate 51 cannot be reduced, a sufficient volume of the gap 60 cannot be ensured and a heat insulating effect cannot be expected. Furthermore, a space for mounting the cooling module 22 cannot be secured. A more preferable Young's modulus is 300 GPa or more. Use of a material having a Young's modulus of 300 GPa or more is particularly preferable because deformation of the bottom substrate 51 can be significantly reduced, and the bottom substrate 51 can be further reduced in size and weight.

  Further, the thermal conductivity of the bottom substrate 51 is preferably 40 W / mK or less. This is because if the thermal conductivity of the bottom substrate 51 exceeds 40 W / mK, the heat applied to the chuck top 10 is easily transferred to the bottom substrate 51 and affects the accuracy of the drive system. In recent years, since a high temperature of 150 to 200 ° C. is required as a temperature during probing, the thermal conductivity of the bottom substrate 51 is more preferably 10 W / mK or less, and particularly preferably 5 W / mK or less. When the thermal conductivity is about 5 W / mK, the amount of heat transferred from the support 50 to the drive system can be significantly reduced.

  Specific materials for the bottom substrate 51 that satisfy these requirements include mullite or alumina, and a composite of mullite and alumina (mullite-alumina composite). It is preferable that mullite has a low thermal conductivity and a large heat insulating effect, and alumina has a high Young's modulus and high rigidity. The mullite-alumina composite is generally preferable because it has a thermal conductivity smaller than that of alumina and a Young's modulus larger than that of mullite.

  Furthermore, the Young's modulus of the first and third support members is preferably 100 GPa or more. When the Young's modulus of the support member is less than 100 GPa, it is necessary to arrange a large number of support members. However, when a large number of support members are arranged, a large number of holes are provided in the cooling module 22 to avoid contact with the cooling module 22. This is not preferable because the necessity arises and the cooling capacity of the cooling module 22 is impaired. Further, like the bottom substrate 51, a more preferable Young's modulus is 200 GPa or more.

  The thermal conductivity of the first to third support members is also preferably 40 W / mK or less, like the bottom substrate 51. This is because if it exceeds 40 W / mK, the heat applied to the chuck top 10 is easily transferred to the bottom substrate 51 and affects the accuracy of the drive system. As described above, since a high temperature of 150 to 200 ° C. is recently required as a temperature during probing, the thermal conductivity of the support member is preferably 10 W / mK or less, and this thermal conductivity is 5 W / mK or less. Is particularly preferred. This is because when the thermal conductivity is about 5 W / mK, the amount of heat transfer from the support 50 to the drive system is significantly reduced.

  As the material of the second and third support members, a material having a thermal expansion coefficient equal to or lower than that of the bottom substrate 51 is preferable. Therefore, the bottom substrate 51 is made of mullite or alumina, and a composite of mullite and alumina (mullite-alumina composite). Body), mullite-alumina composite, silicon nitride, cordierite, and glass are preferable. Mullite-alumina composite and silicon nitride are preferable in that they have a low coefficient of thermal expansion and high rigidity, and cordierite and glass are particularly preferable in that they have a low coefficient of thermal expansion.

  The surface roughness of the contact portion between the first to third support members and the chuck top 10 and / or the bottom substrate 51 is preferably Ra 0.1 μm or more. When the surface roughness is less than Ra 0.1 μm, the contact area between the support member and the chuck top 10 and / or the bottom substrate 51 increases, and the gap between the two becomes relatively small. Since the amount of heat transfer becomes larger than in the above case, it is not preferable. There is no particular upper limit on the surface roughness. However, when the surface roughness Ra is 5 μm or more, the cost for treating the surface may increase.

  As a method for setting the surface roughness to Ra 0.1 μm or more, it is preferable to perform a process such as polishing or sand blasting. However, in this case, it is necessary to appropriately determine the polishing conditions and the blasting conditions and control them to Ra 0.1 μm or more. The surface roughness of the bottom surface of the bottom substrate 51 is preferably Ra 0.1 μm or more. Similarly to the above, the amount of heat transfer to the drive system can be reduced by increasing the surface roughness. As described above, the members can be separated from each other to form a contact interface, and by setting the surface roughness of the contact interface to Ra 0.1 μm or more, heat escaping from the bottom surface of the bottom substrate 51 can be reduced. The amount of power supply to the body 21 can be reduced.

  The perpendicularity between the contact surfaces of the first to third support members and these chuck tops 10 or the contact surface with these bottom substrates 51 is 10 mm or less in terms of a measurement length of 100 mm. It is preferable. This is because when the squareness exceeds 10 mm, the support member itself is likely to be deformed when the pressure applied from the chuck top 10 is applied to the support member. In addition, the squareness means the magnitude of the deviation from the right angle of the parts that must be perpendicular to each other.

  A metal layer is preferably formed on the surface of the bottom substrate 51. This is because the electric field and electromagnetic waves generated from the heating element 21 for heating the chuck top 10, the probe drive unit, and the surrounding equipment, etc., may become noise during wafer inspection, which may have an effect. This is because if a metal layer is formed on the bottom substrate 51, this electromagnetic wave can be blocked. There is no restriction | limiting in particular as a method of forming a metal layer. For example, a conductive paste obtained by adding glass frit to a metal powder such as silver, gold, nickel, or copper can be applied by baking and baked.

  Further, a metal such as aluminum or nickel may be formed by thermal spraying, or a metal layer may be formed on the surface by plating. Further, these methods can be combined. That is, after baking the conductor paste, a metal such as nickel may be plated, or plating may be formed after thermal spraying. Of these techniques, plating or thermal spraying is particularly preferable. Plating is preferable because it has high adhesion strength and high reliability. Thermal spraying is preferable because a metal film can be formed at a relatively low cost.

  Further, the metal layer may include a conductor on at least a part of the surface of the bottom substrate 51. The material used is not particularly limited as long as it is a conductor. For example, stainless steel, nickel, aluminum, or the like can be used.

  As a method of providing a conductor, there is a method of attaching a ring-shaped conductor to the side surface of the bottom substrate 51. That is, the metal foil of the above-described material is formed into a ring shape with a size larger than the outer diameter of the bottom substrate 51 and attached to the side surface of the bottom substrate 51. By making the conductor ring larger than the outer diameter of the chuck top 10, the entire side surface from the bottom of the bottom substrate 51 to the upper surface of the chuck top 10 can be covered without contacting the chuck top 10.

  Further, a metal foil or a metal plate may be attached to the bottom surface portion of the bottom substrate 51, and by connecting this to a metal foil attached to the side surface, the effect of shielding electromagnetic waves (guard effect) can be enhanced. Further, a metal foil or a metal plate may be attached to the upper surface of the bottom substrate 51, and the guard effect can be further enhanced by connecting it to the metal foil attached to the side surface and the bottom surface. By adopting such a method, it is preferable because the guard effect can be obtained at a relatively low cost as compared with the case of applying plating or conductive paste.

  Although there is no restriction | limiting in particular regarding the fixing method of metal foil and a metal plate, and the support body 50, For example, metal foil and a metal plate can be attached to the bottom board | substrate 51 using a metal screw. Moreover, it is preferable to integrate the metal foil and the metal plate of the bottom surface portion and the side surface portion of the bottom substrate 51.

  In the structure of the present embodiment, the cooling module 22 is sandwiched between the chuck top 10 and the warpage preventing plate 30 and preferably brought into close contact with the chuck top 10 and the warpage preventing plate 30 via the soft material 23. The chuck top is supported by the support directly or indirectly via the cooling module, or has a metal cooling module having an internal water channel. Unlike the conventional structure in which is supported by a support, the pressure of the probe card during probing does not act on the cooling module 22 itself, and deformation is extremely small even when used repeatedly.

  Although there is no restriction | limiting in particular about the fixing method of the chuck | zipper top 10 and the curvature prevention board 30, For example, it can fix by mechanical means, such as screwing and a clamp. In addition, when the chuck top 10 and the warp prevention plate 30 are fixed with the heating element 21 and the cooling module 22 sandwiched by screws, the number of screws is set to 3 or more, and further to 6 or more, so that the adhesion between them is improved. This is preferable because the temperature increase / decrease rate and temperature uniformity of the chuck top 10 are further improved.

  As described above, when the cooling module 22 is provided for the chuck top 10, it is possible to prevent the refrigerant from flowing through the cooling module 22 when the temperature rises. As a result, the heat generated in the heating element 21 is not taken away by the refrigerant and escapes out of the system, so that the temperature can be raised more efficiently. In addition, the chuck | zipper top 10 can be cooled efficiently by flowing a refrigerant | coolant to the cooling module 22 at the time of cooling.

  Although there is no restriction | limiting in particular as a material of the cooling module 22, Since aluminum, copper, and its alloy have comparatively high thermal conductivity, since the heat | fever of the chuck | zipper top 10 can be rapidly taken, it is used preferably. In addition, stainless steel, magnesium alloy, nickel, and other metal materials can be used. Furthermore, in order to provide the cooling module 22 with oxidation resistance, a metal film having oxidation resistance such as nickel, gold, or silver can be formed using a technique such as plating or thermal spraying.

  Ceramics can also be used as the material of the cooling module 22. The material in this case is not particularly limited, but aluminum nitride and silicon carbide are preferable because they have a relatively high thermal conductivity and can quickly take heat away from the chuck top 10. Silicon nitride and aluminum oxynitride are preferable because of high mechanical strength and excellent durability. Oxide ceramics such as alumina, cordierite, and steatite are preferable because they are relatively inexpensive.

  As described above, since the material of the cooling module 22 can be variously selected, the material may be appropriately selected depending on the application. Among these, aluminum plated with nickel and copper plated with nickel are particularly preferable because they are excellent in oxidation resistance, have high thermal conductivity, and are relatively inexpensive.

  Further, as described above, it is also possible to flow a refrigerant into the cooling module 22. By doing in this way, since the heat transmitted from the heat generating body 21 to the cooling module 22 can be quickly removed from the cooling module 22, it is preferable because the cooling rate of the heat generating body 21 can be further improved. As the refrigerant flowing through the cooling module 22, water, fluorinate, ethylene glycol, or the like can be selected, and there is no particular limitation.

  As a method for forming the cooling module 22 that is not limited, two copper (oxygen-free copper) plates are prepared, and a flow path for flowing water through one of the copper plates is formed by machining or the like. The other copper plate and a slenless pipe for refrigerant entrance / exit are simultaneously brazed and joined to this copper plate. Nickel plating is applied to the entire surface of the joined cooling plates in order to improve corrosion resistance and oxidation resistance.

  Moreover, as another formation method, it can be set as a cooling module by attaching the pipe which flows a refrigerant | coolant to cooling plates, such as an aluminum plate or a copper plate. In this case, the cooling efficiency can be further increased by forming a counterbored groove having a shape close to the cross-sectional shape of the pipe in close contact with the pipe. Further, in order to improve the adhesion between the pipe and the cooling plate, a heat conductive resin, ceramics, or the like may be inserted as an intervening layer.

  A chuck top conductor layer is formed on the wafer mounting surface 10 a of the chuck top 10. The purpose of forming the chuck top conductor layer is to protect the chuck top 10 from corrosive gases, acids, alkali chemicals, organic solvents, water, etc., which are usually used in semiconductor manufacturing, and to be mounted on the chuck top 10. In order to block electromagnetic noise from the lower part of the chuck top 10 which affects the wafer to be played, it is necessary to play a role of dropping to the ground.

  The method for forming the chuck top conductor layer is not particularly limited, and examples thereof include a technique in which a conductor paste is applied by screen printing and then firing, a technique such as vapor deposition and sputtering, and a technique such as spraying and plating. Of these, thermal spraying and plating are particularly preferable. Because no heat treatment is involved in forming the conductor layer, the chuck top 10 itself is not warped by the heat treatment, and an inexpensive conductor layer having excellent characteristics is formed because the cost is relatively low. Because you can.

  In particular, it is particularly preferable to form a sprayed film on the chuck top 10 and form a plating film thereon. This is because a conductive layer having good adhesion strength and good electrical conductivity can be formed by this method. That is, the sprayed film has better adhesion to ceramics or metal-ceramics than the plated film. This is because the material to be sprayed, such as aluminum or nickel, forms some oxide, nitride or oxynitride during spraying, and the formed compound reacts with the surface layer of the chuck top 10 to strengthen It can adhere. However, since the sprayed film contains these compounds, the conductivity of the film is lowered.

  On the other hand, since plating can form a substantially pure metal, the adhesion strength with the chuck top 10 is not as high as that of the sprayed film, but a conductive layer having excellent conductivity can be formed. Therefore, by forming a sprayed film on the base and forming a plated film thereon, the plated film has a good adhesion strength to the sprayed film in which the sprayed film is a metal, and further has an excellent electrical conductivity. Sex can be imparted.

  Further, the surface roughness of the conductor layer on the chuck top 10 is preferably 0.5 μm or less in terms of Ra. This is because when the surface roughness exceeds 0.5 μm, when measuring a wafer having a large calorific value, the heat generated by the self-heating of the wafer during probing cannot be dissipated from the chuck top 10 and the wafer itself rises. This is because it may be heated and thermally destroyed. The surface roughness Ra is more preferably 0.02 μm or less because heat can be radiated more efficiently.

  When heating by the heating element 21 and probing the wafer on the chuck top 10 at 200 ° C., for example, the temperature of the lower surface of the support 50 is preferably 150 ° C. or less. If the temperature exceeds 150 ° C., the prober drive system provided at the bottom of the support 50 will be distorted due to the difference in thermal expansion coefficient, the accuracy will be impaired, and the probe will be displaced due to misalignment, warping, and deterioration of parallelism during probing. There is a risk that the wafer may not be accurately evaluated due to a defect such as one piece. In addition, when measuring at room temperature after measuring the temperature up to 200 ° C., it takes time to cool from 200 ° C. to room temperature, resulting in poor throughput.

  The Young's modulus of the chuck top 10 is preferably 250 GPa or more, and more preferably 300 GPa. This is because if the Young's modulus is less than 250 GPa, the chuck top 10 bends due to a load applied to the chuck top 10 during probing. As a result, the flatness and the parallelism of the upper surface of the chuck top 10 are remarkably deteriorated, and a probe pin contact failure occurs, so that an accurate inspection cannot be performed. Furthermore, the wafer may be damaged.

  Further, the thermal conductivity of the chuck top 10 is preferably 15 W / mK or more. When it is less than 15 W / mK, the temperature distribution of the wafer placed on the chuck top 10 is deteriorated, which is not preferable. On the other hand, if the thermal conductivity is 15 W / mK or more, it is possible to obtain soaking so as not to hinder probing. An example of such a material having thermal conductivity is alumina having a purity of 99.5% (thermal conductivity 30 W / mK). Particularly preferred is 170 W / mK.

  The thickness of the chuck top 10 is preferably 8 mm or more, and more preferably 10 mm or more. If the thickness is less than 8 mm, the chuck top 10 bends due to the load applied to the chuck top 10 during probing, and the flatness and parallelism of the upper surface of the chuck top 10 are significantly deteriorated. It is because it becomes impossible. In this case, the wafer may be further damaged.

  The material forming the chuck top 10 is preferably a metal-ceramic composite, ceramic, or metal. As the metal-ceramic composite, a composite of aluminum and silicon carbide, or a composite of silicon and silicon carbide, or aluminum, which has relatively high thermal conductivity and is easy to obtain soaking when the wafer is heated. And a composite of silicon and silicon carbide. Among these, a composite of silicon and silicon carbide is particularly preferable because it has a particularly high Young's modulus and a high thermal conductivity.

  In addition, since these composite materials have conductivity, as a method of forming the resistance heating element 21a, for example, an insulating layer is formed on the surface opposite to the wafer mounting surface by a method such as spraying or screen printing. Then, the conductor layer can be screen-printed thereon, or the conductor layer can be formed in a predetermined pattern by a technique such as vapor deposition, thereby forming the resistance heating element 21a.

  Further, a metal foil such as stainless steel, nickel, silver, molybdenum, tungsten, dichrome, and alloys thereof can be formed into a resistance heating element 21a by forming a predetermined heating element pattern by etching. In this method, the insulation with the chuck top 10 can be formed by the same method as described above. For example, an insulating sheet can be inserted between the chuck top 10 and the heating element. This method is preferable because the insulating layer can be easily formed at a lower cost than the above method.

  Examples of the resin that can be used in this method include mica sheet, epoxy resin, polyimide resin, phenol resin, and silicon resin from the viewpoint of heat resistance. Of these, mica is particularly preferable. The reason is that it has excellent heat resistance, electrical insulation, good workability, and is inexpensive.

  Further, when ceramics is used as the material of the chuck top 10, it is relatively easy to use because there is no need to form an insulating layer as described above. In addition, as a method for forming the resistance heating element 21a in this case, a method similar to the above can be selected. Among the ceramic materials, alumina, aluminum nitride, silicon nitride, mullite, and a composite of alumina and mullite are particularly preferable. Since these materials have a relatively high Young's modulus, they are particularly preferable because they are less deformed by the pressing of the probe card. Among these, alumina is the most excellent because it is relatively inexpensive and has excellent electrical characteristics at high temperatures.

  It is also possible to apply metal to the material of the chuck top 10. In this case, it is also possible to use tungsten, molybdenum and alloys thereof having a particularly high Young's modulus. Specific examples of the alloy include an alloy of tungsten and copper and an alloy of molybdenum and copper. These alloys can be produced by impregnating copper into tungsten or molybdenum. Since these metals are conductors like the above ceramic-metal composite, the above method is applied as it is to form a chuck top conductor layer and a heating element to form the chuck top 10. Can be used.

  When a load of 3.1 MPa is applied to the chuck top 10, the amount of deflection is preferably 30 μm or less. Since a large number of probe pins for inspecting the wafer from the probe card are pressed against the wafer on the chuck top 10, the pressure also affects the chuck top 10, and the chuck top 10 is bent at least. If the amount of deflection at this time exceeds 30 μm, the probe pins of the probe card cannot be uniformly pressed against the wafer, and the wafer cannot be inspected. The amount of deflection when this pressure is applied is more preferably 10 μm or less.

  The wafer holder for a wafer prober of the present invention can be suitably used for heating and inspecting an object to be processed such as a wafer. For example, if it is applied to a wafer prober, a handler device or a tester device, it is possible to take advantage of the characteristics of high rigidity and high thermal conductivity, and it is preferable because high accuracy can be maintained even at high temperatures and low temperatures.

  As described above, the wafer holder for a wafer prober of the present invention has been described based on the embodiments. However, the present invention is not limited to such embodiments, and can be implemented in various modes without departing from the gist of the present invention. Should be understood. That is, the technical scope of the present invention extends to the claims and their equivalents.

[Example 1]
Samples 1 to 9 were prepared by the following method. First, a Si—SiC substrate having a thermal expansion coefficient of 3 × 10 ⁻⁶ / K was used, and this was processed into a chuck top 10 having a diameter of 310 mm and a thickness of 10 mm. Vacuum chucking grooves and holes were formed on the wafer mounting surface 10a of the chuck top 10, and nickel plating was performed to form a chuck top conductor layer.

Next, a copper cooling module 22 is installed under the chuck top 10, and a heating element formed by etching a stainless steel foil is sandwiched between silicon resin containing Al ₂ O ₃ powder under the cooling module 22. The body 21 was installed. A 500 μm thick silicon resin containing Al ₂ O ₃ powder was inserted between the chuck top 10 and the cooling module 22.

  Further, a warpage prevention plate 30 having the same diameter and thickness as the chuck top 10 is installed below the heat generating element 21, and the warpage prevention plate 30 and the chuck top 10 are fixed by screws. When the warp prevention plate 30 and the chuck top 10 are screwed, a gap is set so that the screw, the cooling module 22 and the heating element 21 do not come into contact with each other at the time of temperature increase or decrease. A thermocouple for measuring temperature was attached to the lower part of the warpage preventing plate 30.

Here, the material of the warp preventing plate 30 using Si—SiC with a thermal expansion coefficient of 3 × 10 ⁻⁶ / K was used as Sample 1, and AlN with a thermal expansion coefficient of 4.5 × 10 ⁻⁶ / K was used. Sample 2 with a thermal expansion coefficient of 4.2 × 10 ⁻⁶ / K using Al—SiC Sample 3 and using Al ₂ O ₃ with a thermal expansion coefficient of 7 × 10 ⁻⁶ / K Is a sample 4, a sample using W having a thermal expansion coefficient of 4.5 × 10 ⁻⁶ / K is a sample 5, and a sample using Mo having a thermal expansion coefficient of 5.2 × 10 ⁻⁶ / K is a sample 6. Sample 7 was made of stainless steel having a thermal expansion coefficient of 17.3 × 10 ⁻⁶ / K, and sample 8 was made of SiC using a thermal expansion coefficient of 3.2 × 10 ⁻⁶ / K. Sample 9 was prepared using 4.8 × 10 ⁻⁶ / K kovar.

  For each of these samples 1 to 9, the amount of warpage of the wafer mounting surface 10a of the chuck top 10 at normal temperature (20 ° C.) is measured with a contact displacement meter, and then a voltage is applied to the heating element 21. The amount of deformation of the wafer mounting surface 10a of the chuck top 10 at 200 ° C. with respect to room temperature was measured with a contact-type displacement meter, and the amount of deformation at −60 ° C. was also measured in the same manner. At −60 ° C., dry air was flowed to prevent condensation. Furthermore, the thermal uniformity of the wafer at 200 ° C. was also measured using a wafer thermometer. A thermocouple was attached to the lower part of the warpage preventing plate 30 and the temperature at 200 ° C. was measured. The results are shown in Table 1 below.

Next, an AlN substrate having a thermal expansion coefficient of 4.5 × 10 ⁻⁶ / K is used as the chuck top 10, Ti is deposited on the wafer mounting surface 10 a side of the AlN substrate, and a Mo film is formed by deposition. After that, a Ni plating film was formed to form a chuck top conductor layer. In the same manner as above, the cooling module 22, the heating element 21, and the warpage prevention plate 30 were attached to the obtained chuck top 10 to obtain samples 10 to 18. Measurement was performed on each of these samples 10 to 18 in the same manner as the above samples 1 to 9. The results are shown in Table 2 below.

次に、チャックトップ１０として、熱膨張係数７×１０^−６／ＫのＡｌ_２Ｏ_３基板を使用した以外は上記試料１０〜１８のＡｌＮ基板と同様にしてチャックトップ導体層の形成、及び冷却モジュール２２、発熱体２１、反り防止板３０の取り付けを行って試料１９〜２７とした。これら試料１９〜２７のそれぞれに対して、上記試料１〜１８と同様に測定を行った。その結果を下記の表３示す。

Next, the chuck top conductor layer is formed and cooled in the same manner as the AlN substrates of Samples 10 to 18 except that an Al ₂ O ₃ substrate having a thermal expansion coefficient of 7 × 10 ⁻⁶ / K is used as the chuck top 10. The module 22, the heating element 21, and the warpage preventing plate 30 were attached to obtain samples 19 to 27. Measurement was performed on each of the samples 19 to 27 in the same manner as the above samples 1 to 18. The results are shown in Table 3 below.

この表１〜３の結果から、チャックトップ１０と反り防止板３０の熱膨張係数差が小さければ小さいほどチャックトップ１０の温度が変化してもチャックトップ１０の反りの変化が小さいことがわかる。特にこの熱膨張係数差が２×１０^−６／Ｋ以下の場合、チャックトップ１０の反りの変化が極めて小さいことがわかる。また、チャックトップ１０の熱伝導率が高いほど均熱性に優れていることがわかる。

From the results of Tables 1 to 3, it can be seen that the smaller the difference in thermal expansion coefficient between the chuck top 10 and the warp preventing plate 30, the smaller the change in the warp of the chuck top 10 even if the temperature of the chuck top 10 changes. In particular, when the difference in coefficient of thermal expansion is 2 × 10 ⁻⁶ / K or less, it can be seen that the change in the warp of the chuck top 10 is extremely small. It can also be seen that the higher the thermal conductivity of the chuck top 10, the better the heat uniformity.

[Example 2]
As shown in Table 4 below, the chuck top 10 using Si—SiC as the material, the heating element 20 including the cooling module 22 and the heating element 21, and any of Si—SiC, AlN, or Mo as the material. The warpage preventing plate 30 used is coupled with the structure shown in any of FIGS. 2A to 2C, and the silicon containing Al ₂ O ₃ powder having a thickness of 500 μm is interposed between the heating element 21 and the warpage preventing plate 30. Samples 28 to 36 were produced in the same manner as in Example 1 except that the resin was inserted.

  In addition, the thickness of the outer peripheral portion was 6 mm in all of FIGS. In addition, the cooling module 22 and the heating element 21 are provided with a gap that does not come into contact with the inner side surface of the outer peripheral thick portion at the time of heating and cooling. These samples 28 to 36 were measured in the same manner as in Example 1. The results are shown in Table 4 below.

Next, as shown in Table 5 below, the above except that AlN is used as the material of the chuck top 10 and Si-SiC, AlN, or Al ₂ O ₃ is used as the material of the warpage preventing plate 30. Samples 37 to 45 were produced in the same manner as Samples 28 to 36. Measurements were performed on these samples 37 to 45 in the same manner as in Example 1. The results are shown in Table 5 below.

Next, as shown in Table 6 below, Al ₂ O ₃ is used as the material for the chuck top 10 and any one of Al ₂ O ₃ , Mo, or SiC is used as the material for the warp prevention plate 30. Samples 46 to 54 were produced in the same manner as the above samples 28 to 45. These samples 46 to 54 were measured in the same manner as in Example 1 above. The results are shown in Table 6 below.

  From the results of Tables 4 to 6, also in the structures of FIGS. 2A to 2C, the temperature of the chuck top 10 changes as the difference in thermal expansion coefficient between the chuck top 10 substrate and the warp prevention plate 30 decreases. Even so, it can be seen that the change in the warp of the chuck top 10 is small.

[Example 3]
As shown in Table 7 below, the chuck top 10 using Si—SiC as the material, the heating element 20 including the cooling module 22 and the heating element 21, and any of Si—SiC, AlN, or Mo as the material. The warpage prevention plate 30 used is coupled with the structure shown in FIG. 3 or FIG. 4, and further, Al ₂ having a thickness of 500 μm is interposed between the chuck top 10 and the cooling module 22 and between the heating element 21 and the warpage prevention plate 30. Samples 55 to 60 were produced in the same manner as in Example 1 except that a silicon resin containing O ₃ powder was inserted.

  3 has a width of 6 mm, a mullite-alumina composite was used for the chuck top 10, and the thermal expansion coefficient was matched with that of the chuck top 10. In addition, for the support column in FIG. 4, pipe-shaped ceramics having an outer diameter of 10 mm and an inner diameter of 6 mm are used, and the material is a mullite-alumina composite so as to match the thermal expansion coefficient of the chuck top 10 as described above. did.

  Further, the cooling module 22 and the heating element 21 are provided with a gap that does not contact the inner side surface of the ring-shaped member in FIG. 3 at both the temperature rise and cooling, and does not contact the outer peripheral side surface of the support member in FIG. Only a gap was provided. Measurements were performed on these samples 55 to 60 in the same manner as in Example 1. The results are shown in Table 7 below.

Next, as shown in Table 8 below, AlN was used as the material for the chuck top 10 and Si-SiC, AlN, or Al ₂ O ₃ was used as the material for the warp prevention plate 30. Samples 61 to 66 were produced in the same manner as Samples 55 to 60. Measurements were performed on these samples 61 to 66 in the same manner as in Example 1. The results are shown in Table 8 below.

Next, as shown in Table 9 below, Al ₂ O ₃ is used as the material of the chuck top 10, and any of Al ₂ O ₃ , Mo, or SiC is used as the material of the warp prevention plate 30. Samples 67 to 72 were prepared in the same manner as Samples 55 to 66 except that Al ₂ O ₃ was used as the material of the ring-shaped member 3 and the support pillars of FIG. These samples 67 to 72 were measured in the same manner as in Example 1. The results are shown in Table 9 below.

  From the results of Tables 7 to 9, even in the structure of FIG. 3 or FIG. 4, the smaller the coefficient of thermal expansion between the chuck top 10 substrate and the warp prevention plate 30 is, the smaller the chuck top 10 temperature changes. It can be seen that the change in warpage of the top 10 is small.

[Example 4]
A support having the structure shown in FIG. 7A, FIG. 8 and FIG. 6 was attached to each of the samples 58 to 59 used in Example 3 to prepare samples 73 to 78. Further, samples other than the thickness of the warpage preventing plate 30 were set to 3 mm, and the same samples as the samples 73 to 78 were prepared as samples 79 to 84, respectively.

  A mullite-alumina composite pipe having a diameter of 10 mm and an inner diameter of 6 mm was used for the first to third support members, and a mullite-alumina composite having an outer diameter of 310 mm and an inner diameter of 288 mm was also used for the second ring member. The bottom substrate 51 was an alumina substrate having a diameter of 310 mm. These samples 73 to 84 were measured in the same manner as in Example 1.

  Furthermore, the temperature raising / lowering speed and rigidity were also measured. The temperature rising / falling speed was determined by the total arrival time from room temperature (RT) to 200 ° C and from RT to -60 ° C. The rigidity was compared by measuring the amount of deformation of the top surface of the chuck top 10 with a displacement meter when the same load was applied to the chuck top 10. In addition, (circle) has shown that the measurement result was favorable, and (double-circle) has shown that the measurement result was very favorable. The results are shown in Table 10 below.

  Next, Samples 85 to 96 were produced in the same manner as Samples 58 to 59 for Samples 64 to 65 used in Example 3 above. These samples 85 to 96 were measured in the same manner as the samples 73 to 84. The results are shown in Table 11 below.

  Next, Samples 97 to 104 were produced in the same manner as Samples 58 to 59 and Samples 64 to 65 for Samples 70 to 71 used in Example 3 above. These samples 97 to 104 were measured in the same manner as the samples 73 to 96. The results are shown in Table 12 below.

  From the results of Tables 10 to 12, it was found that the temperature of the bottom substrate 51 can be significantly reduced. It can also be seen that the smaller the difference in thermal expansion coefficient between the chuck top 10 substrate and the warp preventing plate 30 is, the smaller the warp of the chuck top 10 is at high and low temperatures regardless of the thickness. On the other hand, as the thickness of the warp prevention plate 30 is thicker, the rigidity is increased, and as the thickness is reduced, the temperature raising / lowering speed is increased. Therefore, it was found that the design can be appropriately performed according to the conditions. That is, by setting the difference in thermal expansion coefficient between the chuck top 10 substrate and the warpage prevention plate 30 to a predetermined value or less, it is possible to reduce the warpage during temperature rise and fall and to increase the rigidity, the warpage prevention plate 30 is made thicker. If it is desired to increase the temperature raising / lowering speed, the warpage prevention plate 30 can be made thin.

[Example 5]
A support was attached to each of the samples 1, 2 and 9 used in Example 1 so as to have the structure shown in FIG. Further, samples 108 to 110 were prepared by preparing the same samples 105 to 107 except that the thickness of the warpage preventing plate 30 was 3 mm.

  A mullite-alumina composite pipe having a diameter of 10 mm and an inner diameter of 6 mm was used as the support member, and an alumina substrate having a diameter of 310 mm was used as the bottom substrate 51. Measurements were performed on these samples 105 to 110 in the same manner as in Example 4. The results are shown in Table 13 below.

  Next, Samples 111 to 116 were produced in the same manner as Samples 1, 2, and 9 for Samples 10, 11, and 18 used in Example 1 above. These samples 111 to 116 were measured in the same manner as the samples 105 to 110 described above. The results are shown in Table 14 below.

Next, Samples 117 to 122 were prepared for Samples 22, 24, and 25 used in Example 1 in the same manner as Samples 1, 2, and 9, and Samples 10, 11, and 18, respectively. However, for the samples 119 and 122, the material of the warpage preventing plate 30 was Ti having a thermal expansion coefficient of 8.4 × 10 ⁻⁶ / K. These samples 117 to 122 were measured in the same manner as the above 105 to 116. The results are shown in Table 15 below.

  From the results of Tables 13 to 15, in the structure of FIG. 10, the smaller the difference in thermal expansion coefficient between the chuck top 10 substrate and the warp prevention plate 30 regardless of the thickness, the higher the temperature of the chuck top 10 at both high and low temperatures. It can be seen that the warpage is reduced. On the other hand, even if the thickness of the warpage preventing plate 30 is thick, it does not contribute to rigidity, and the temperature raising / lowering speed becomes faster as the thickness is reduced.

[Example 6]
For the samples 73 to 122 of Examples 4 and 5, the temperature control means is replaced with a structure in which the heating elements 21 are provided on both the upper and lower sides of the cooling module 22 as shown in FIG. Was made. These samples 123 to 172 were measured in the same manner as the above samples 73 to 122. The results are shown in Tables 16 to 21 below.

  From the results of Tables 16 to 21, it can be seen that the warpage of the chuck top 10 is further reduced by providing the heating elements 21 both above and below the cooling module 22.

[Example 7]
Of the samples 1 to 122 produced in Examples 1 to 5, a 300 mm wafer was placed on the samples shown in Table 22 below, and probing was performed at 200 ° C. The results are shown in Table 22 below. “◎” indicates that there was no problem even if the test was continued for 24 hours, and “◯” indicated that there was no problem even if the test was continued for 12 hours. X indicates that a shift has occurred, and x indicates that a situation in which probing cannot be performed from the initial stage has occurred.

  From the results in Table 22, it can be seen that the smaller the difference in the coefficient of thermal expansion between the chuck top 10 substrate and the warp prevention plate 30, the less likely it is to cause problems during probing.

DESCRIPTION OF SYMBOLS 1 Wafer holder for wafer probers 10 Chuck top 20 Temperature control means 21 Heat generating element 22 Cooling module 23 Soft material 30 Warpage prevention plate 40 First support member 50 Support body 51 Bottom substrate 52 Second support member 53 Third support member 60 Gap Part 70 fastening means

Claims (9)

  A chuck top having a wafer mounting surface, a temperature control means installed on the chuck top on a surface opposite to the wafer mounting surface, and a temperature control means installed on a surface opposite to the surface facing the chuck top. And a support having a gap is provided at a lower portion of the warpage prevention plate, and a difference in thermal expansion coefficient between the warpage prevention plate and the chuck top is a predetermined value or less. A wafer holder for a wafer prober.   A chuck top having a wafer placement surface; and a warp prevention plate installed on a surface of the chuck top opposite to the wafer placement surface, and a support having a gap at a lower portion of the warpage prevention plate. And a storage portion is provided between the chuck top and the warp prevention plate, and the storage portion is provided with a temperature control means, and thermal expansion between the warpage prevention plate and the chuck top is provided. A wafer holder for a wafer prober, wherein the coefficient difference is not more than a predetermined value.   The wafer holder for a wafer prober according to claim 1, further comprising a first support member between the chuck top and the warpage prevention plate.   4. The wafer holder for a wafer prober according to claim 3, wherein the first support member has a first ring-shaped member, and the storage portion is formed inside the first ring-shaped member. .   The support body includes a bottom substrate, a second support member disposed on the bottom substrate and supporting the warpage prevention plate and / or a third support member supporting the chuck top, A wafer holder for a wafer prober according to claim 1.   The wafer holder for a wafer prober according to claim 5, wherein the second support member includes a plurality of second support columns and a second ring-shaped member.   The temperature control unit includes a heating element and a cooling module, and the heating element, the cooling module, and the heating element are stacked in this order from the chuck top side, and are sandwiched between the chuck top and the warpage prevention plate. A wafer holder for a wafer prober according to any one of claims 1 to 6.   A temperature control unit for a wafer prober comprising the wafer holder for a wafer prober according to claim 1.   A wafer prober comprising the temperature control unit according to claim 8.

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