JP6525794B2 - Wafer heating device - Google Patents

Description

  The present invention relates to a wafer heating apparatus used to heat a wafer.

  As a wafer heating apparatus, for example, a wafer heating apparatus described in Japanese Patent Laid-Open No. 2001-237166 (hereinafter, also referred to as Patent Document 1) is known. The wafer heating apparatus described in Patent Document 1 includes a heat equalizing plate and a support that supports the heat equalizing plate. One main surface of the heat spreader is a mounting surface on which the wafer is placed, and a heating resistor is formed on the other main surface. The heat spreader plate is fixed by being pushed up from the support side by an elastic body formed of a coil spring provided on the center side and restraining on the support side by an elastic body formed of bolts provided on the outer peripheral side. Thus, the deformation generated in the heat spreader is reduced by pressing the heat spreader in the vertical direction.

JP 2001-237166 A

  However, in the wafer heating device described in Patent Document 1, the outer peripheral portion of the heat spreader is notched in order to attach a bolt to the outer peripheral portion of the heat spreader. The cut-off portion of the other main surface of the heat spreader has a shape different from that of the other portions, and the degree of heat transfer may also be different from that of the other portions. Therefore, it has been difficult to improve the heat uniformity on the mounting surface.

  The present invention has been made in view of such problems, and an object thereof is to improve the thermal uniformity of a wafer heating apparatus.

The wafer heating apparatus according to the present invention comprises a base whose upper surface is a sample holding surface, a heating resistor provided on the inner side or the lower side of the base, and a support positioned below the base to support the base. And a pressing member positioned between the base and the support, and a plurality of fasteners for fixing the substrate and the support, the fastener having one end holding the sample An upper part which is fixed on the outer peripheral side of the surface and whose other end is fixed to the support and which is positioned directly above the sample holding surface to press the sample holding surface and continuous with the upper part And a side portion which is located laterally of the outer periphery of the sample holding surface and which extends downward below the lower surface of the base, and which is continuous with the side portion and which is at least directly under the base It further has a lower part where the part is located, said lower part and the front Wherein the gap there Rukoto between the substrates.

  According to the wafer heating device of one aspect of the present invention, one end of the fastener is continuous with the upper part located immediately above the sample holding surface to press the sample holding surface, and the upper part, and the sample holding surface And a lateral portion which is located laterally of the outer periphery of the base and extends below the lower surface of the base, and the other end is fixed to the support without providing the base with a notch. , The substrate can be suppressed. Therefore, the temperature uniformity of the wafer heating apparatus can be improved.

It is a sectional view showing the wafer heating device of one embodiment of the present invention. It is a perspective view which shows a fastener among the wafer heating apparatuses shown in FIG. It is a perspective view which shows the 1st member among the fasteners shown in FIG. It is a perspective view which shows the 2nd member among the fasteners shown in FIG. It is a perspective view which shows the 3rd member among the fasteners shown in FIG.

  Hereinafter, a wafer heating apparatus 10 according to an embodiment of the present invention will be described. As shown in FIG. 1, the wafer heating apparatus 10 comprises a substrate 1, a heating resistor 9 provided on the substrate 1, a support 2 positioned below the substrate 1 to support the substrate 1, and the substrate 1. And a plurality of fasteners 3 for fixing the support 2. The wafer heating apparatus 10 further includes a pressing member 8 located between the base 1 and the support 2. In addition, in FIG. 1, the fastener 3 and the pressing member 8 are expanded and shown for convenience.

  The base 1 is a member having a sample holding surface 11 on the top surface. The base 1 is, for example, a disk-shaped member. The substrate 1 is made of ceramics. As the ceramics, ceramics having silicon carbide, boron carbide, boron nitride, silicon nitride or aluminum nitride as a main component can be used. For the dimensions of the substrate 1, for example, the diameter of the main surface can be set to 200 to 500 mm, and the thickness can be set to 1 to 7 mm.

  The heating resistor 9 is a member for heating a sample (a holding object) such as a wafer. The heating resistor 9 is provided inside or on the lower surface of the base 1. In the wafer heating apparatus 10 of the present embodiment, the heating resistor 9 is provided on the lower surface of the base 1. The heating resistor 9 is formed, for example, in a strip shape. The heat generating resistor 9 is made of, for example, a metal material such as gold, silver, palladium or platinum.

  The support 2 is a member for supporting the base 1. The support 2 is positioned below the substrate 1 to support the substrate 1. The base 1 and the support 2 are fixed by a plurality of pressing members 8 and fasteners 3, respectively. For example, one pressing member 8 is provided at the center of the lower surface of the wafer heating device 10, eight in a circle between the center and the outer periphery, and eight along the outer periphery. The pressing member 8 is made of, for example, a coil spring. The fasteners 3 are provided, for example, on the outer peripheral side of the wafer heating device 10 at equal intervals in the circumferential direction. The base 1 is fixed by being pushed up from the support 2 side by the pressing member 8 and restraining to the support 2 side by the fastener 3 provided on the outer peripheral side. As described above, by pressing the base 1 in the vertical direction, the deformation generated in the heat spreader is reduced. In addition, in FIG. 1, the force which the press member 8 pushes up the base | substrate 1, and the force which hold down the support body 2 are shown by the white arrow.

  The fastener 3 is a member for pressing the base 1 to the support 2 side. In the wafer heating apparatus 10 of the present embodiment, the fastener 3 roughly holds the base 1 and the support 2 by utilizing the elastic force of the spring. The fastener 3 of this embodiment is comprised by the 1st member 4 shown in FIG. 2, the 2nd member 5 and the 3rd member 6, and the spring member 7 (coil spring). First, the configuration of each of the first member 4, the second member 5 and the third member 6 will be described, and then a method of fixing the base 1 and the support 2 using the fastener 3 will be described.

  The first member 4 is a member having a portion that holds the base 1. As shown in FIG. 3, the first member 4 is continuous with the upper portion 41 for holding the sample holding surface 11 and the upper portion 41 and is located laterally from the outer periphery of the sample holding surface 11. It has a side portion 42 extending to the lower surface, and a lower portion 43 which is continuous with the side portion 42 and which is at least partially located immediately below the base 1. When viewed from the side, the upper portion 41, the side portions 42 and the lower portion 43 are U-shaped, and the base 1 is held in the U-shape. At this time, the lower surface of the upper portion 41 presses the sample holding surface 11 of the base 1. The first member 4 has a rod-like portion 44 directed downward from the lower surface of the lower portion 43. The rod portion 44 has a thread 45 at its lower end. The first member 4 is made of, for example, a metal material such as stainless steel.

  The second member 5 is a member for fixing the fastener 3 to the support 2. As shown in FIG. 4, the second member 5 is a substantially plate-like member, and has a through hole 51 at the center. The portion having the through hole 51 is formed to be thicker than other portions. Specifically, the second member 5 has a shape in which a cylindrical member is provided on the upper surface of a plate-like member having the through holes 51 so that the through holes 51 are continuous. The through hole 51 has a diameter that allows insertion of the rod portion 44 described above. The second member 5 has, in addition to the central through hole 51, two through holes (hereinafter, also referred to as support body fixing holes 52) so as to sandwich the through hole 51. The support fixing hole 52 is a through hole for fixing the second member 5 to the support 2 using a bolt or the like. The second member 5 is made of, for example, a metal material such as stainless steel.

  As shown in FIG. 5, the third member 6 is a tubular member. The third member 6 has a smaller inner diameter at the lower end side. At this time, the inner diameter on the upper end side of the third member 6 is larger than the outer diameter of the spring member 7, and the inner diameter on the lower end side is smaller than the outer diameter of the spring member 7. Therefore, when the spring member 7 is inserted from the upper end side of the third member 6, the spring member 7 stays inside the third member 6. In other words, the spring member 7 does not come off from the lower end side in the third member 6. Further, on the inner peripheral surface on the lower end side of the third member 6, a threading 61 corresponding to the threading 45 on the lower end of the rod-like portion 44 of the first member 4 is provided. That is, the rod-like portion 44 of the first member 4 and the inner peripheral surface of the lower end of the third member 6 can be fixed by screws. The third member 6 is made of, for example, a metal material such as stainless steel.

  Next, a method of fixing the base 1 and the support 2 using the fastener 3 will be described. First, the second member 5 is fixed to the support 2 using the support fixing holes 52 of the second member 5. A bolt etc. can be used for fixation. In addition, fixing may be performed by using an adhesive or the like without using the support fixing holes 52. Next, the rod-like portion 44 of the first member 4 is inserted into the through hole 51 of the second member 5. At this time, the base 1 is adjusted to be positioned between the upper portion 41 and the lower portion 43 of the first member 4. Next, the third member 6 and the spring member 7 are attached to the rod portion 44 from the lower end side of the rod portion 44 in a state where the spring member 7 is inserted into the third member 6. At this time, the third member 6 is attached such that the rod portion 44 penetrates the spring member 7 and the third member 6. Since the lower surface of the third member 6 is provided with a threading 61 corresponding to the threading 45 of the rod portion 44, the third member 6 should be rotated in a direction perpendicular to the axial direction of the rod portion 44. Thus, the third member 6 can be brought close to the second member 5 and fixed.

  At this time, as the third member 6 is moved closer to the second member 5, the spring member 7 inserted into the third member 6 has the upper end in contact with the second member 5 and the lower end is the third member 6 Will come into contact with In this state, when the third member 6 is moved closer to the second member 5, the spring member 7 is crushed by the third member 6 and the second member 5, and an elastic force is generated in the spring member 7. . In FIG. 2, the force generated on the spring member 7 is indicated by an open arrow A. Since the second member 5 is fixed to the support 2 and does not move, the elastic force acts to push the third member 6 downward. The downward force is indicated by an outlined arrow B. Since the third member 6 is fixed to the first member 4 by the screw threads 45 and 61, the first member 4 is pulled downward by the third member 6. This downward force is indicated by the outlined arrow C. When the force (white arrow C) pulling the first member 4 downward is transmitted from the upper portion 41 to the sample holding surface 11 of the substrate 1, the upper portion 41 can hold the sample holding surface 11.

As described above, in the wafer heating apparatus 10 according to the present embodiment, the fastener 3 is fixed to the outer peripheral side of the sample holding surface 11 and the other end is fixed to the support 2. An upper portion 41 positioned immediately above 11 to hold down the sample holding surface 11 and an upper portion 41 are continuous with the upper portion 41 and positioned below the outer periphery of the sample holding surface 11 and extend downward below the lower surface of the base 1 And a side portion 42. Thereby, the base 1 can be suppressed without providing the notch in the base 1. Therefore, by providing the notches, it is possible to prevent the degree of heat buildup from changing. As a result, the temperature uniformity of the wafer heating apparatus 10 can be improved.

  In addition, as shown in FIG. 1, there may be a gap between the side portion 42 and the base 1. As a result, when the base 1 is thermally expanded, the thermal expansion easily occurs on the side surface, so that the thermal stress generated between the fastener 3 and the base 1 can be reduced. Therefore, the possibility of the occurrence of cracks in the substrate 1 can be reduced.

  In addition, when the fastener 3 further includes the lower portion 43 in which one end portion is continuous with the side portion 42 and at least a portion thereof is located directly below the base body 1, the base body 1 is suppressed. , Between the lower portion 43 and the side portion 42. Therefore, since the pressing of the substrate 1 by the fastener 3 can be performed gently, the possibility of the occurrence of a crack in the substrate 1 can be reduced.

  Furthermore, as shown in FIG. 1, there may be a gap between the lower portion 43 and the base 1. As a result, when a voltage is applied to the heating resistor 9 provided on the lower surface of the base 1, the possibility of the occurrence of electrical leakage between the fastener 3 and the heating resistor 9 can be reduced.

  Furthermore, the upper portion 41 and the lower portion 43 may extend from the outer periphery toward the center, and the lower portion 43 may be longer than the upper portion 41. As a result, since the lower portion 43 can be bent when the fastener 3 pulls the base 1 downward, the pressing with the fastener 3 can be performed gently. Furthermore, by shortening the upper portion 41, the area of the portion of the fastener 3 in contact with the base 1 can be reduced. Therefore, the heat buildup by the fastener 3 can be reduced. As a result, the temperature uniformity of the sample holding surface 11 can be improved.

  Furthermore, at least a part of the heat generating resistor 9 may be provided between the upper portion 41 and the lower portion 43 of the fastener 3. Thus, heating by the heat generating resistor 9 can be performed even in the range where the fastener 3 is disposed. Thereby, the temperature uniformity of the wafer heating apparatus 10 can be further improved.

1: base 11: sample holding surface 2: support 3: fastener 4: first member 41: upper portion 42: upper portion 42: lower portion 44: rod portion 45: threading 5: second member 51: penetrating Hole 52: support fixing hole 6: third member 61: threading 7: spring member 8: pressing member 9: heating resistor 10: wafer heating device

Claims (4)

A base whose upper surface is a sample holding surface, a heating resistor provided inside or under the base, a support positioned below the base to support the base , the base, and the support a pressing member located between, and a plurality of fasteners for securing the said substrate and the support,
One end of the fastener is fixed to the outer peripheral side of the sample holding surface, and the other end is fixed to the support, and the sample is positioned directly on the sample holding surface. It has an upper part for holding the holding surface, and a side part which is continuous with the upper part and which is located laterally of the outer periphery of the sample holding surface and which extends below the lower surface of the base. square portion further has a lower portion at least partially positioned immediately below the substrate is continuous with, a wafer heating apparatus according to claim gap there Rukoto between said lower portion and the base.   The wafer heating apparatus according to claim 1, wherein a gap is provided between the side portion and the base. Together with the upper portion and the lower portion extends toward the center side from the outer periphery of the substrate than the upper portion of claim 1 or claim 2 towards the lower portion and wherein the longer Wafer heating device. The wafer heating apparatus according to any one of claims 1 to 3 , wherein at least a part of the heat generating resistor is provided between an upper portion and a lower portion of the fastener.

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