KR20220147512A - Wafer heating apparatus - Google Patents

Abstract

The present invention provides a wafer heating apparatus in which wiring is hardly sandwiched between a heater unit and a cooling plate when cooling the heater unit. The wafer heating apparatus according to the present invention includes: a heater unit that is equipped with an upper surface on which a wafer is placed and a heater heating the wafer; a cooling plate that cools the heater unit; and wiring that is drawn from a lower surface of the heater unit. The cooling plate is configured to be movable between a state in which an upper surface of the cooling plate comes in contact with the lower surface of the heater unit and a state in which the upper surface of the cooling plate is separated from the lower surface of the heater unit. The cooling plate is equipped with a recessed part provided on the upper surface and a first through-hole penetrating in a thickness direction from a position of a bottom portion of the recessed part. The wiring is drawn to the lower surface side of the cooling plate through the recessed part and the first through-hole in a state in which the cooling plate and the heater unit come in contact with each other. The heating apparatus can be stably cooled.

Description

Wafer heating apparatus {WAFER HEATING APPARATUS}

The present disclosure relates to a wafer heating apparatus.

Patent Document 1 discloses, for example, a wafer heating apparatus for heating a wafer in a photolithography process. The wafer heating apparatus of patent document 1 is equipped with the heater unit which heats a wafer, and the movable cooling module which cools the heater unit. The wafer is placed on the upper surface of the heater unit. The heater unit includes a heater including a resistance heating element. The movable cooling module is configured to be movable up and down. When the movable cooling module contacts the lower surface of the heater unit, the heater unit is cooled.

The heater unit has wiring for supplying electric power to the resistance heating element. The wiring is led out from the lower surface of the heater unit. Since the wiring serves as a heat transfer path, there is a possibility that a cool spot may be formed in the heater unit. In order to solve this problem, in the wafer heating apparatus of patent document 2, a part of wiring is fixed to the lower surface of a heater unit. By fixing the wiring to the heater unit, the wiring is warmed by the heater unit. As a result, it becomes difficult to form a cool spot on the heater unit.

Patent Document 1: Japanese Patent Laid-Open No. 2011-129577 Patent Document 2: Japanese Patent Laid-Open No. 2011-187257

In a wafer heating apparatus including a cooling plate, when the cooling plate is in contact with the heater unit, there is a fear that wiring is pinched between the heater unit and the cooling plate. If the wiring is caught between the heater unit and the cooling plate, the contact area between the heater unit and the cooling plate is reduced, and there is a risk that the temperature decrease rate of the heater unit is slowed. In addition, there is a possibility that the insulation coating of the wiring sandwiched between the heater unit and the cooling plate may be damaged.

An object of the present disclosure is to provide a wafer heating apparatus capable of stably cooling the heater unit because wiring is difficult to be caught between the heater unit and the cooling plate when the heater unit is cooled.

The wafer heating apparatus of the present disclosure,

A heater unit comprising an upper surface on which a wafer is disposed and a heater for heating the wafer;

a cooling plate for cooling the heater unit;

and a wiring drawn out from the lower surface of the heater unit,

wherein the cooling plate is configured to be movable between a state in which an upper surface of the cooling plate is in contact with a lower surface of the heater unit and a state in which an upper surface of the cooling plate is separated from a lower surface of the heater unit. ,

The cooling plate includes a concave portion provided on an upper surface and a first through hole penetrating in a thickness direction from a position of a bottom portion of the concave portion;

In a state where the heater unit and the cooling plate are in contact with each other, the wiring is led out to the lower surface side of the cooling plate through the concave portion and the first through hole.

In the wafer heating apparatus of the present disclosure, stable cooling of the heater unit is enabled.

1 is a schematic configuration diagram of a wafer heating apparatus according to a first embodiment;
Fig. 2 is a partially enlarged view of the wafer heating apparatus according to the first embodiment;
Fig. 3 is a partially enlarged view showing a state in which the cooling plate of the wafer heating apparatus shown in Fig. 2 is in contact with the heater unit;
Fig. 4 is a partial plan view of a cooling plate provided in the wafer heating apparatus according to the first embodiment;
Fig. 5 is a partial plan view of a cooling plate different from Fig. 4;
6 is a schematic diagram of a wafer heating apparatus according to a second embodiment;
Fig. 7 is a plan view of a heater provided in the wafer heating apparatus according to the third embodiment;
Fig. 8 is a plan view of a cooling plate provided in the wafer heating apparatus according to the third embodiment;

[Description of embodiment of the present disclosure]

Hereinafter, embodiments of the present disclosure will be listed and described.

<1> The wafer heating apparatus according to the embodiment,

A heater unit comprising an upper surface on which a wafer is disposed and a heater for heating the wafer;

a cooling plate for cooling the heater unit;

and a wiring drawn out from the lower surface of the heater unit,

wherein the cooling plate is configured to be movable between a state in which an upper surface of the cooling plate is in contact with a lower surface of the heater unit and a state in which an upper surface of the cooling plate is separated from a lower surface of the heater unit. ,

The cooling plate includes a concave portion provided on an upper surface and a first through hole penetrating in a thickness direction from a position of a bottom portion of the concave portion;

In a state where the heater unit and the cooling plate are in contact with each other, the wiring is led out to the lower surface side of the cooling plate through the concave portion and the first through hole.

In the wafer heating apparatus according to the embodiment, in a state in which the heater unit and the cooling plate are in contact, the wiring is configured such that the wiring is led out to the lower surface side of the cooling plate through the concave portion and the first through hole provided in the cooling plate. Therefore, in the wafer heating apparatus according to the embodiment, the wiring is hardly caught between the heater unit and the cooling plate. If the wiring is caught between the heater unit and the cooling plate, there is a problem that the contact area between the heater unit and the cooling plate decreases, and there are problems that the wiring is damaged. Since the wafer heating apparatus according to the embodiment can significantly reduce the possibility of such a problem occurring, it is possible to stably and repeatedly cool the heater unit.

<2> As an aspect of the wafer heating apparatus which concerns on embodiment,

A part of the middle part of the wiring is fixed to the lower surface of the heater unit,

The intermediate portion may be disposed inside the concave portion in a state in which the heater unit and the cooling plate are in contact.

Since a part of the middle portion of the wiring is fixed to the lower surface of the heater unit, the wiring is warmed by the heater unit, and heat is hardly emitted from the heater unit through the wiring. As a result, it is difficult to form a cool spot on the heater unit. In order for a part of the middle part of the wiring to be fixed to the lower surface of the heater unit, the middle part needs to be bent along the lower surface of the heater unit. In the configuration of the aspect <2>, since the intermediate portion of the bent wiring is configured to be disposed in the concave portion, the intermediate portion of the wiring is hardly pinched between the heater unit and the cooling plate.

<3> As an aspect of the wafer heating apparatus according to the aspect <2>,

The first through hole may have a form in which the intermediate portion is disposed below a location where the intermediate portion is fixed to the heater unit.

In the configuration of the aspect <3>, the wiring is guided to the first through hole without being excessively bent. Therefore, the wiring is hardly damaged.

<4> As one aspect of the wafer heating apparatus according to the embodiment,

The heater unit includes a support plate for supporting the heater from below;

the cooling plate is configured to be movable between a state in which an upper surface of the cooling plate is in contact with a lower surface of the support plate and a state in which an upper surface of the cooling plate is separated from a lower surface of the support plate;

The support plate is provided with a second through hole penetrating in the thickness direction,

The concave portion is provided such that a continuous space is formed between the upper opening of the first through hole and the lower opening of the second through hole in a state in which the support plate and the cooling plate are in contact;

The said wiring may take the form which is extended below the said support plate through the said 2nd through-hole.

When the heater unit is provided with the support plate, the flatness of the wafer holding plate is maintained favorably, so that the cracking property of the wafer holding plate is increased. Since the support plate is a highly rigid body, the thickness of the heater unit including the wafer holding plate can be reduced. As a result, the heat capacity of the heater unit is reduced, and the temperature increase rate and temperature decrease rate of the heater unit are improved. In addition, the support plate can suppress direct contact of the cooling plate with the heater. Therefore, even if the number of times the cooling plate contacts the heater unit increases, the heater is less likely to be damaged.

<5> As one aspect of the wafer heating apparatus according to the aspect <4>,

At room temperature, the projection outline of the second through hole is located inside the outline of the opening of the concave portion;

The projected contour may be a contour in which the contour of the lower opening is projected onto the cooling plate.

When the high-temperature heater unit and the low-temperature cooling plate come into contact, the heater unit contracts and the cooling plate expands. In that case, the wiring may contact the inner wall of a recessed part. When the wiring is fixed to the lower surface of the heater unit, if stress is applied to the wiring, the fixed state of the wiring may change or the wiring may come off. In the configuration of the above aspect <5>, in which the concave portion is larger than the projected outline of the second through hole, the wiring hardly comes into contact with the inner wall of the concave portion.

<6> As one aspect of the wafer heating apparatus according to the embodiment,

The cooling plate includes a main body and an upper layer disposed on the upper surface of the main body;

The body is made of metal,

The upper layer may be formed of a material different from that of the main body.

Various effects are obtained by the material of the upper layer. For example, when the upper layer is made of a silicone resin, the adhesiveness between the heater unit and the cooling plate increases, and the heater unit is easily cooled quickly. Further, when the heater unit and the cooling plate come into contact, both the heater unit and the cooling plate are less likely to be damaged.

<7> As an aspect of the wafer heating apparatus according to the embodiment,

The heater is provided with a plurality of heating zones,

The upper surface of the cooling plate is provided with a plurality of cooling zones,

Each cooling zone is a virtual area corresponding to each heating zone,

The form in which the area Sa inside the outer periphery of each cooling zone and the contact area Sb with the said heater unit in each cooling zone satisfy|fills Sb/Sa >=0.5 is mentioned.

A heater provided with a plurality of heating zones can reduce the cracking range of the wafer. The cracking range of a wafer means the temperature nonuniformity in the surface inside of a wafer when a wafer is heated. In the structure of the said aspect <7>, the area in which the cooling zone corresponding to each heating zone contacts a support plate is prescribed|regulated. When the entire surface of the lower surface of the heater unit and the upper surface of the cooling plate are in contact, the area Sa and the contact area Sb of the cooling zone are the same. However, since recesses and holes are formed on the upper surface of the cooling plate, the contact area Sb becomes smaller than the area Sa of the cooling zone. If the contact area with the heater unit in each cooling zone is equal to or greater than a predetermined value, the entire heater unit is rapidly cooled.

<8> As one aspect of the wafer heating apparatus according to the aspect <7>,

The plurality of cooling zones include a first cooling zone having the largest Sb/Sa and a second cooling zone having the smallest Sb/Sa,

A difference between Sb/Sa of the first cooling zone and Sb/Sa of the second cooling zone may be 0.35 or less.

In the structure of the said aspect <8>, it is hard to produce nonuniformity in the cooling rate of each heating zone. Therefore, the whole heater unit is cooled uniformly in a short time.

<9> As an aspect of the wafer heating apparatus according to aspect <7> or aspect <8>,

The plurality of cooling zones include a third cooling zone and a fourth cooling zone adjacent to each other,

An area inside the outer circumferential line of the third cooling zone is smaller than an area inside the outer circumferential line of the fourth cooling zone,

The wiring includes a first wiring extending from the heating zone corresponding to the third cooling zone,

The concave portion includes a first concave portion corresponding to the first wiring,

At least a portion of the first concave portion may be disposed in the fourth cooling zone.

In the structure of the said aspect <9>, it is suppressed that the contact area with the heater unit in a 3rd cooling zone becomes small too much. By arrange|positioning a recessed part in the 3rd cooling zone, the contact area with the heater unit of a 3rd cooling zone becomes small. If a recess is further formed in the third cooling zone having an area smaller than the area of the fourth cooling zone, the difference between the contact area of the third cooling zone with the heater unit and the contact area of the fourth cooling zone with the heater unit becomes larger. Since a part of the concave portion provided in the third cooling zone is disposed in the fourth cooling zone, the difference in the contact area with the heater unit can be reduced. Accordingly, the configuration of the aspect <9> easily satisfies the provisions of the aspect <7> and the aspect <8>.

[Details of embodiment of the present disclosure]

Hereinafter, specific examples of a wafer heating apparatus and a wafer holding plate according to an embodiment of the present disclosure will be described with reference to the drawings. The same reference numerals in the drawings indicate the same or equivalent parts. The size of the member shown in each figure is expressed for the purpose of making description clear, and does not necessarily show an actual dimension. In addition, this invention is not limited to these illustrations, It is shown by a claim, and it is intended that the meaning of a claim and equivalent and all the changes within the range are included.

<Embodiment 1>

≪Overall composition≫

The wafer heating apparatus 1 of the embodiment shown in Figs. 1 to 3 is used for pre-baking in a photolithography process and the like. The pre-bake is a heat treatment in which the solvent of the photoresist solution applied to the surface of the wafer 100 is volatilized. The wafer heating apparatus 1 includes a heater unit 10 that heats the wafer 100 and a cooling unit 11 that cools the heater unit 10 . The cooling plate 5 provided in the cooling unit 11 is configured to be movable up and down, and cools the heater unit 10 as necessary. In the partially enlarged view of FIG. 2 , the state in which the cooling plate 5 is separated from the heater unit 10 is shown. A state in which the cooling plate 5 is in contact with the heater unit 10 is shown in the partially enlarged view of FIG. 3 . Hereinafter, each structure of the wafer heating apparatus 1 which concerns on embodiment is demonstrated in detail.

≪Heater unit≫

The heater unit 10 of the present example includes a wafer holding plate 2 , a heater 3 , and a supporting plate 4 in order from above. As shown in Embodiment 2 mentioned later, the support plate 4 is not essential.

[Wafer retaining plate]

The wafer holding plate 2 has a flat upper surface 2U on which the wafer 100 is placed. The upper surface 2U constitutes the upper surface 10U of the heater unit 10 . The wafer holding plate 2 in this example is an original plate. The diameter of the disk may be larger than that of the wafer 100 mounted on the upper surface 10U, and is, for example, 200 mm or more and 400 mm or less. The planar shape of the wafer holding plate 2 is not limited to a circular shape, and for example, a polygonal shape such as a square may be used. The planar shape of the wafer holding plate 2 is preferably a shape similar to the planar shape of the wafer 100 .

It is preferable that the material of the wafer holding plate 2 is a material which is excellent in thermal conductivity and is hard to deform|transform by heat. Preferred materials include copper, aluminum, or an alloy containing these. It is preferable to perform nickel plating or anodizing on the surface of the wafer holding plate 2 . In addition, ceramics can also be used as the material of the wafer holding plate 2 . Examples of the ceramics include ceramics such as aluminum nitride, silicon carbide (SiC), aluminum oxide, or silicon nitride, or a composite of these ceramics and silicon (Si). In particular, Si-SiC in which a porous body of SiC is impregnated with metallic silicon is preferable as the material of the wafer holding plate 2 .

The wafer holding plate 2 may be provided with a projection (not shown), a vacuum port, a lift pin hole, and the like. The projection is provided on the upper surface 2U. The protrusion forms a minute gap between the upper surface 2U and the wafer 100 . The vacuum port and the lift pin hole are holes penetrating the wafer holding plate 2 in the thickness direction. When air is sucked from the gap between the upper surface 2U and the wafer 100 through the vacuum port, the wafer 100 is corrected to be flat and close. The lift pin hole is a hole through which a lift pin for lifting the wafer 100 from the upper surface 2U is inserted. A vacuum port and a lift pin hole are also provided in the heater 3 and the support plate 4 mentioned later.

A temperature measuring element 25 is provided on the lower surface 2D of the wafer holding plate 2 of this example. The temperature of the wafer holding plate 2 measured by the temperature measuring element 25 is used to control the heater 3 to be described later. The temperature measuring element 25 is arranged, for example, in a spot facing hole 20 provided on the lower surface 2D. Examples of the temperature measurement element 25 include a temperature measurement element in which a platinum resistor is formed on ceramics by vapor deposition. The temperature measuring element 25 is fixed with, for example, a silicone adhesive or the like. A wiring 70 is connected to the temperature measuring element 25 . The arrangement state of the wiring 70 will be described later.

[heater]

The heater 3 is a member that heats the wafer holding plate 2 . The wafer 100 is heat-treated by the wafer holding plate 2 heated by the heater 3 . The heater 3 is provided with the plate-shaped base material 31 comprised by the insulator, and the circuit pattern 30 of the resistance heating element comprised by metal. The base material 31 constitutes the outer shape of the heater 3 . The base material 31 in this example has a disk shape having an outer diameter equal to that of the wafer holding plate 2 . 2, 3, in the heater 3 of this example, the circuit pattern is arrange|positioned inside the base material 31. As shown in FIG. The circuit pattern 30 is constituted by, for example, a thin metal film that generates heat by energization. As the circuit pattern 30, for example, a circuit pattern 30 formed by partially etching a foil of stainless steel, or the like. The base material 31 may be, for example, a resin having excellent heat resistance such as polyimide. In addition, examples of the base material 31 include a mica sheet impregnated with a resin, ceramics, and the like. In this example, the heater 3 is produced by sandwiching the circuit pattern 30 between two polyimide sheets.

A blind hole 35 and a third through hole 36 are formed in the base material 31 of the heater 3 . The blind hole 35 reaches the terminal of the circuit pattern 30 from the lower surface 3D of the heater 3 . A wire 7 for energization is connected to the terminal. The wiring 7 is arranged inside the blind hole 35 . The third through hole 36 penetrates the substrate 31 in the thickness direction. The upper end of the third through hole 36 is opened in the spot facing hole 20 . The wiring 70 connected to the temperature measuring element 25 arranged in the spot facing hole 20 is arranged inside the third through hole 36 . The blind hole 35 and the third through hole 36 may be blocked with a resin or the like.

[Support plate]

The support plate 4 supports the heater 3 from below. Since the flatness of the wafer holding plate 2 is maintained favorably by the supporting plate 4 , the crackability of the wafer holding plate 2 is increased. Since the support plate 4 is a high rigidity body, the thickness of the heater unit 10 including the wafer holding plate 2 can be reduced. As a result, the heat capacity of the heater unit 10 becomes small, and the temperature increase rate and temperature decrease rate of the heater unit 10 improve. In this example, the lower surface 4D of the support plate 4 constitutes the lower surface 10D of the heater unit 10 . The cooling plate 5 of the cooling unit 11 is in contact with the lower surface 4D of the support plate 4 when the heater unit 10 is cooled. Since the cooling plate 5 does not come into direct contact with the heater 3 by the support plate 4, the heater 3 is less likely to be damaged. The support plate 4 of this example is a disk shape which has the same outer diameter as the wafer holding plate 2 . In this example, the support plate 4, the wafer holding plate 2, and the heater 3 are integrated with a fastening screw or the like not shown. Like the wafer holding plate 2, it is preferable that the support plate 4 is comprised by ceramics.

The supporting plate 4 has a plurality of second through holes 45 and 46 penetrating in the thickness direction. The second through hole 45 at a position corresponding to the terminal of the circuit pattern 30 is connected to the blind hole 35 of the heater 3 . The wiring 7 connected to the circuit pattern 30 is disposed inside the second through hole 45 through the blind hole 35 . The second through hole 46 at a position corresponding to the temperature measuring element 25 is connected to the third through hole 36 of the heater 3 . The wiring 70 connected to the temperature measuring element 25 is disposed inside the second through hole 45 through the third through hole 36 as shown in FIG. 2 . The second through holes 45 and 46 in which the wirings 7 and 70 are arranged may be blocked with a resin or the like.

≪Cooling unit≫

The cooling unit 11 is configured to cool the heater unit 10 as necessary. The cooling unit 11 includes a cooling plate 5 and a cooling stage 6 .

[Cooling Stage]

The cooling stage 6 is maintained at a low temperature by a refrigerant or the like. For example, a refrigerant flow path is formed inside the cooling stage 6 . The cooling stage 6 has a role of cooling the cooling plate 5 . The cooling stage 6 also has a role of holding the heater unit 10 above the cooling stage 6 . Specifically, the cooling stage 6 and the heater unit 10 are connected by a fixed shaft 60 . The fixed shaft 60 passes through the cooling plate 5 , and the cooling plate 5 is not fixed by the fixed shaft 60 .

[Cool plate]

The cooling plate 5 is configured to be movable up and down. For example, the cooling plate 5 is attached to the front end of the rod of an air cylinder (not shown). When the heater unit 10 is cooled, the cooling plate 5 at a low temperature moves upward through the cooling stage 6 , and the lower surface 4D of the support plate 4 , that is, the lower surface of the heater unit 10 . (10D) is in contact. When the cooling plate 5 comes into contact with the lower surface 10D of the heater unit 10 , the heater unit 10 is rapidly cooled, and the temperature of the heater unit 10 is adjusted to a desired temperature. After cooling of the heater unit 10 is completed, the cooling plate 5 moves away from the lower surface 4D of the support plate 4 and descends to a position in contact with the cooling stage 6 .

The cooling plate 5 of this example is provided with the disk-shaped main body 50 and the upper layer 51 arrange|positioned on the upper surface of the main body 50. As shown in FIG. Unlike this example, the cooling plate 5 may not have the upper layer 51 . The body 50 is preferably made of a material having excellent thermal conductivity, for example, metal. The main body 50 of this example is comprised by the aluminum alloy.

The upper layer 51 has a function of improving the adhesion between the cooling plate 5 and the heater unit 10 . The upper layer 51 in this example is a resin sheet. The material of the upper layer 51 is preferably a material rich in flexibility, for example, containing silicon or fluorine as a main component. The upper layer 51 excellent in flexibility improves the adhesion between the cooling plate 5 and the heater unit 10 , and improves the cooling efficiency of the heater unit 10 by the cooling plate 5 . In addition, the upper layer 51 excellent in flexibility suppresses damage to the main body 50 of the cooling plate 5 and the heater unit 10 when the cooling plate 5 comes into contact with the heater unit 10 .

The cooling plate 5 has recesses 52 and 53 and first through holes 55 and 56 . The concave portion 52 and the concave portion 53 have the same configuration. The first through hole 55 and the first through hole 56 have the same configuration. Accordingly, in the following description, the concave portion 52 and the first through hole 55 will be mainly described.

The concave portion 52 is a recessed portion provided on the upper surface 5U of the cooling plate 5 . The first through hole 55 is a through hole that penetrates in the thickness direction of the cooling plate 5 from the position of the bottom portion 52b of the concave portion 52 . As shown in FIG. 3 , the recessed portion 52 is in a state where the heater unit 10 and the cooling plate 5 are in contact with the upper opening 55h of the first through hole 55 and the second through hole. It is provided so that the continuous space may be formed between the lower opening part 45h of 45. The axis of the first through hole 55 and the axis of the second through hole 45 are arranged at different positions in the plane direction of the cooling plate 5 . Unlike this example, the axis line of the first through hole 55 and the axis line of the second through hole 45 may coincide with each other.

As shown in FIG. 4 which is a partial top view of the cooling plate 5, at normal temperature, the projected outline 45v of the 2nd through-hole 45 is inside the outline of the opening part 52h of the recessed part 52. It is preferable to be located in The projected contour line 45v is a contour line obtained by projecting the contour line of the lower opening portion 45h of the second through hole 45 shown in FIG. 3 onto the cooling plate 5 . The wiring 7 led out into the recess 52 is guided inside the first through hole 55 .

As shown in FIG. 5, the projection outline 45v arrange|positioned inside the outline of the opening part 52h of the recessed part 52 may be plural. In the example shown in FIG. 5, the outline shape of the opening part 52h of the recessed part 52 is a substantially V-shape. A wiring 7 connected to the circuit pattern 30 shown in FIG. 3 and a wiring 70 connected to the temperature measuring element 25 shown in FIG. 3 are formed in one recess 52 in one recess. (52) is withdrawn into the interior. The wiring 7 and the wiring 70 arranged in the recessed portion 52 are guided inside one first through hole 55 . The outline shape of the opening part 52h is not specifically limited. For example, the outline shape of the opening part 52h may be an approximately L-shape or may be an elongated hole shape. In the case of the concave portion 52 having the elongated hole-shaped opening 52h, the first through hole 55 is disposed at the central portion in the longitudinal direction of the concave portion 52, and the two projection outlines 45v are the concave portion. (52) is preferably disposed at both ends in the longitudinal direction.

≪Wiring≫

2 and 3 , the wiring 7 connected to the circuit pattern 30 is led out below the heater unit 10 through the second through hole 45 . A part of the intermediate portion 7c of the wiring 7 drawn out from the second through hole 45 is fixed to the lower surface 10D of the heater unit 10 . The wiring 7 drawn out from the second through hole 45 is led out to the lower surface 5D side of the cooling plate 5 through the first through hole 55 and is connected to a power source (not shown). The first through hole 55 is disposed below a location where the intermediate portion 7c is fixed to the lower surface 10D of the heater unit 10 . Therefore, the wiring 7 is guided to the first through hole 55 without excessively bending the intermediate portion 7c.

The wiring 70 connected to the temperature measuring element 25 is led out below the support plate 4 through the second through hole 46 . A part of the intermediate portion 70c of the wiring 70 is also fixed to the lower surface 10D of the heater unit 10 . The wiring 70 drawn out from the second through hole 46 is led out to the lower surface 5D side of the cooling plate 5 through the first through hole 56 and is connected to a temperature measuring device (not shown).

As shown in FIG. 3 , in the state where the heater unit 10 and the cooling plate 5 are in contact, the intermediate portions 7c and 70c of the wirings 7 and 70 are located inside the recesses 52 and 53 . are placed That is, the wirings 7 and 70 are not sandwiched between the heater unit 10 and the cooling plate 5 , and the concave portion 52 and the first through hole 55 or the concave portion 53 and the first It is drawn out to the lower surface 5D side of the cooling plate 5 through the through hole 56.

The intermediate portion 7c of the wiring 7 and the intermediate portion 70c of the wiring 70 are fixed to the lower surface 10D of the heater unit 10 with, for example, an adhesive or the like. Alternatively, the intermediate portions 7c and 70c may be fixed to the lower surface 10D by an adhesive sheet or the like. Since the intermediate portions 7c and 70c of the wirings 7 and 70 are fixed to the lower surface 10D of the heater unit 10 , it becomes difficult to form a cool spot in the heater unit 10 .

In the wafer heating apparatus 1 of this example, in the state in which the heater unit 10 and the cooling plate 5 are in contact, the wirings 7 and 70 are recessed parts 52 and 53 with which the cooling plate 5 is equipped. ) and the first through holes 55 and 56 to be drawn out toward the lower surface of the cooling plate 5 . Therefore, in the wafer heating apparatus 1 , the wirings 7 and 70 are hardly caught between the heater unit 10 and the cooling plate 5 . Therefore, the problem caused by the wirings 7 and 70 being pinched between the heater unit 10 and the cooling plate 5 can be avoided. Specific problems include a problem that the contact area between the heater unit 10 and the cooling plate 5 decreases, and a problem that the wirings 7 and 70 are damaged.

When the high temperature heater unit 10 and the low temperature cooling plate 5 come into contact, the heater unit 10 contracts and the cooling plate 5 expands. At that time, there is a possibility that the wirings 7 and 70 come into contact with the inner walls of the recesses 52 and 53 . When a stress is applied to the wirings 7 and 70 due to contact with the inner wall, there is a risk that the fixed state of the wirings 7 and 70 changes or the wirings 7 and 70 come off. As a result, there is a possibility that a cool spot is formed in the heater unit 10 . In response to this problem, in the wafer heating apparatus 1 of this example, as shown in FIG. 4 , the projected outline 45v of the second through hole 45 is inside the outline of the opening 52h of the concave portion 52 . is located in Therefore, when the heater unit 10 contracts and the cooling plate 5 expands, it is difficult for the wirings 7 and 70 to contact the inner walls of the recesses 52 and 53 .

<Embodiment 2>

In Embodiment 2, the wafer heating apparatus 1 provided with the heater unit 10 which does not have the support plate 4 is demonstrated based on FIG. Configurations other than the heater unit 10 of the wafer heating apparatus 1 of this example are the same as those of the wafer heating apparatus 1 of the first embodiment.

In the wafer heating apparatus 1 of this example, the lower surface 3D of the heater 3 constitutes the lower surface 10D of the heater unit 10 . Accordingly, the wiring 7 drawn out from the blind hole 35 opened in the lower surface 3D of the heater 3 is guided to the first through hole 55 of the cooling plate 5 . In addition, the wiring 70 drawn out from the third through hole 36 opened in the lower surface 3D of the heater 3 is guided to the first through hole 56 of the cooling plate 5 . Also in the wafer heating apparatus 1 of this example, the wirings 7 and 70 are connected between the heater unit 10 and the cooling plate 5 due to the presence of the recesses 52 and 53 provided in the cooling plate 5 . hard to get stuck

Unlike the structure of FIG. 6 , the circuit pattern 30 may be formed on the lower surface 2D of the wafer holding plate 2 by metallization. In that case, after connecting the wirings 7 and 70 to the circuit pattern 30 , the lower surface 2D including the circuit pattern 30 is coated with an insulating resin or the like, so that the heater 3 is integrated into the lower surface 2D. ) is formed. In this configuration, the blind hole 35 and the third through hole 36 are not formed in the heater 3 .

<Embodiment 3>

In Embodiment 3, the wafer heating apparatus 1 in which the heater 3 with which the heater unit 10 is equipped is equipped with the some heating zone 8 is demonstrated based on FIGS. The basic configuration of the wafer heating apparatus 1 of the third embodiment is the same as that of the wafer heating apparatus 1 of the first embodiment. Accordingly, for configurations not shown in FIGS. 7 and 8 , reference may be made to FIG. 1 .

The heater 3 of this example shown in FIG. 7 is equipped with the some heating zone 8. As shown in FIG. The plurality of heating zones 8 include three heating zones 8A arranged on the inner peripheral side and six heating zones 8B arranged on the outer peripheral side. The heating zone 8A on the inner peripheral side has a sectoral shape with an inner angle of 120°. The area of the three heating zones 8A on the inner peripheral side is the same. The outer peripheral heating zone 8B has a belt shape having an inner circumferential arc of an inner angle of 60° and an outer circumferential arc. The area of the six heating zones 8B on the outer peripheral side is the same. The area of the heating zone 8A on the inner peripheral side is smaller than the area of the heating zone 8B on the outer peripheral side. Each heating zone 8 is provided with an independent circuit pattern. In FIG. 7, illustration of a circuit pattern is abbreviate|omitted. The number of heating zones 8 and the shape of the heating zones 8 are not specifically limited.

The cooling plate 5 of this example shown in FIG. 8 is equipped with the some cooling zone 9. As shown in FIG. The plurality of cooling zones 9 include three cooling zones 9A disposed on the inner circumferential side and six cooling zones 9B disposed on the outer circumferential side. Each cooling zone 9 is a virtual area|region corresponding to each heating zone 8 shown in FIG. More specifically, the region in which the heating zone 8 of FIG. 7 is projected onto the cooling plate 5 of FIG. 8 is the cooling zone 9 . Therefore, the shape of each cooling zone 9 is congruent with the shape of the corresponding heating zone 8 .

The cooling plate 5 is provided with a plurality of concave portions 52 for accommodating the wirings 7 of the circuit pattern 30 . One wiring 7 is arranged in each concave portion 52 . In FIG. 8, illustration of the recessed part 53 which accommodates the wiring 70 of the temperature measuring element 25, the hole for lift pins, a vacuum port, etc. is abbreviate|omitted.

The number of the recessed parts 52 of this example is the same as the number of the heating zones 8 shown in FIG. When a plurality of wirings 7 are arranged in one concave portion 52 , the number of concave portions 52 is at least better than the number of heating zones 8 .

When the area in which the cooling zone 9 contacts the heater unit 10 is small, the time for cooling the heater unit 10 becomes long. In order to improve the productivity of the semiconductor chip, it is necessary to increase the cooling rate of the heater unit 10 . In addition, in order to reuse the heater unit 10, the entire heater unit 10 needs to be at a predetermined temperature or lower. If the cooling rate of each heating zone 8 is non-uniform, the time until reuse of the heater unit 10 becomes long depending on the cooling time of the heating zone 8 with the slowest cooling rate. Therefore, it is preferable that the contact area with the heater unit 10 in each cooling zone 9 satisfy|fills at least one of the condition 1 and condition 2 shown below. Hereinafter, the "contact area of the cooling zone 9 with the heater unit 10" may be simply expressed as "the contact area of the cooling zone 9".

≪Condition 1≫

The area Sa inside the outer peripheral line of each cooling zone 9 and the contact area Sb of each cooling zone 9 satisfy|fill Sb/Sa >=0.5.

Since each cooling zone 9 satisfies the above condition 1, when the cooling plate 5 comes into contact with the heater unit 10, the heating zone 8 corresponding to each cooling zone 9 is rapidly cooled. As a result, the time until reuse of the heater unit 10 is shortened. The cooling rate of the heating zone 8 becomes fast, so that Sb/Sa is large. Preferred Sb/Sa is 0.6 or more, and more preferably Sb/Sa is 0.7 or more.

≪Condition 2≫

The difference (ΔSb/Sa) between Sb/Sa in the first cooling zone 91 and Sb/Sa in the second cooling zone 92 is 0.35 or less.

Here, the 1st cooling zone 91 is the cooling zone 9 with the largest Sb/Sa among the some cooling zones 9. As shown in FIG. In this example, the cooling zone 9B on the outer peripheral side is the 1st cooling zone 91. The second cooling zone 92 is a cooling zone 9 having the smallest Sb/Sa among the plurality of cooling zones 9 . In this example, the cooling zone 9A on the inner peripheral side is the 2nd cooling zone 92. As shown in FIG.

In the heater unit 10 provided with the several heating zone 8, in order to maintain the heating zone 8 which has reached|attained the predetermined temperature at predetermined temperature, the heating zone 8 is heated intermittently by intermittent energization. . If there is non-uniformity in the cooling rate of each heating zone 8, cooling of the heating zone 8 which has not yet reached a predetermined temperature is inhibited by the intermittent heating of the heating zone 8 which has reached|attained predetermined temperature. Therefore, if there is a non-uniformity in the cooling rate of each heating zone 8, the cooling time of the heater unit 10 whole will become long easily. On the other hand, if the plurality of cooling zones 9 satisfy the above condition 2, it is difficult to produce a large difference in the cooling rate of each heating zone 8, and there is no non-uniformity in the time for each heating zone 8 to reach a predetermined temperature. difficult to occur Therefore, the whole heater unit 10 is easy to cool uniformly, and the heater unit 10 tends to quickly fall below a predetermined temperature. It is preferable that the difference (ΔSb/Sa) be smaller. A more preferable difference (ΔSb/Sa) is 0.30 or less, and a more preferable difference (ΔSb/Sa) is 0.2 or less.

As a configuration satisfying the above conditions 1 and 2, the size of the concave portion 52 and the arrangement of the concave portion 52 may be adjusted. In the cooling plate 5 of this example, the some recessed part 52 among the some recessed parts 52 is provided so that it may span the some cooling zone 9,9. Specifically, the first concave portion 54 satisfying the following conditions is provided so as to span the third cooling zone 93 and the fourth cooling zone 94 .

In this example, the plurality of cooling zones 9 include a third cooling zone 93 and a fourth cooling zone 94 adjacent to each other. Here, the area inside the outer circumferential outline of the third cooling zone 93 is smaller than the area inside the outer circumferential outline of the fourth cooling zone 94 . In this example, the cooling zone 9A on the inner peripheral side is the 3rd cooling zone 93. The cooling zone 9B adjacent to the outer peripheral side of the third cooling zone 93 is the fourth cooling zone 94 .

Of the wirings 7 disposed in each recess 52 , the wiring 7 extending from the heating zone 8 corresponding to the third cooling zone 93 is the first wiring 71 . The concave portion 52 in which the first wiring 71 is disposed is the first concave portion 54 . In this example, a part of this 1st recessed part 54 is arrange|positioned in the 4th cooling zone 94. As shown in FIG. In this configuration, the first through hole 55 connected to the first concave portion 54 is also disposed in the fourth cooling zone 94 . A part of the first concave portion 54 is disposed in the fourth cooling zone 94 larger than the third cooling zone 93 , so that the contact area of the third cooling zone 93 is that of the fourth cooling zone 94 . It is suppressed from becoming too small compared with a contact area. As a result, the conditions 1 and 2 are likely to be satisfied.

Unlike this example, the whole of the 1st recessed part 54 may be arrange|positioned in the 4th cooling zone 94. As shown in FIG. In order to achieve this configuration, for example, the first wiring 71 connected to the heating zone 8A on the inner periphery of FIG. 7 is drawn out to the cooling zone 9B on the outer periphery of FIG. 2 The axis of the through hole 45 is tilted. Alternatively, the terminals of the inner periphery heating zone 8A are provided at the positions of the outer periphery heating zone 8B.

<Test Example>

In the test example, the influence of the difference (ΔSb/Sa) between Sb/Sa in the first cooling zone 91 and Sb/Sa in the second cooling zone 92 on the cooling time of the heater unit 10 was investigated. did.

A wafer heating apparatus 1 of Sample No. 1 to Sample No. 5 having a plurality of heating zones 8 and a plurality of cooling zones 9 was prepared. The only difference between these wafer heating apparatuses 1 is the value of the difference (ΔSb/Sa). ΔSb/Sa of the wafer heating apparatus 1 of Sample No. 1, Sample No. 2, Sample No. 3, Sample No. 4, and Sample No. 5 was 0.1, 0.2, 0.3, 0.4, and 0.5, respectively. Sb/Sa of the 1st cooling zone 91 and Sb/Sa of the 2nd cooling zone 92 of each sample are shown below.

・Sample No. 1

Sb/Sa=0.6 of the first cooling zone 91, Sb/Sa=0.5 of the second cooling zone 92

・Sample No.2

Sb/Sa=0.7 of the first cooling zone 91, Sb/Sa=0.5 of the second cooling zone 92

・Sample No.3

Sb/Sa=0.8 of the first cooling zone 91, Sb/Sa=0.5 of the second cooling zone 92

・Sample No.4

Sb/Sa=0.9 of the first cooling zone 91, Sb/Sa=0.5 of the second cooling zone 92

・Sample No. 5

Sb/Sa=0.9 of the first cooling zone 91, Sb/Sa=0.4 of the second cooling zone 92

The heater 3 provided in the wafer heating apparatus 1 of each sample was energized, and the temperature of all the heating zones 8 of the heater 3 was maintained at 150 degreeC. The temperature of each heating zone 8 was measured by the temperature measuring element 25 . Then, after the electricity supply to the heater 3 was temporarily stopped, the cooling plate 5 of the cooling unit 11 was made to contact the support plate 4 . Each heating zone 8 is cooled to 100 °C ± 0.5 °C. Each heating zone 8 is heated intermittently by intermittent energization in order to maintain 100 degreeC ± 0.5 degreeC. In this test, the cooling time until the temperature of all the heating zones 8 of the heater 3 became 100 degreeC ± 0.5 degreeC was measured. The results are shown in Table 1. The unit of cooling time is seconds (s).

As shown in Table 1, it was found that the cooling time of the entire heater 3 in the wafer heating apparatus 1 becomes shorter as the difference (ΔSb/Sa) becomes smaller. In particular, the cooling time of the heater 3 of Sample No. 1, Sample No. 2, and Sample No. 3 having a difference (ΔSb/Sa) of 0.35 or less was 50 seconds or less. On the other hand, the cooling time of the heater 3 of Sample No. 4 and Sample No. 5 in which ΔSb/Sa was more than 0.35 was more than 70 seconds.

The reason that the cooling time of the heater 3 becomes short is guessed as follows, so that the difference (DELTA)Sb/Sa becomes small. The heating zone 8 cooled in the first cooling zone 91 with the largest Sb/Sa reaches 100° C. earlier than the heating zone 8 cooled in the second cooling zone 92 with the smallest Sb/Sa. do. As the difference (ΔSb/Sa) decreases, the time for the temperature of the heating zone 8 cooled in the first cooling zone 91 to reach 100° C. and the heating zone cooled in the second cooling zone 92 ( The difference in time for the temperature of 8) to reach 100°C becomes smaller. Therefore, the frequency|count and time of the intermittent heating for maintaining the heating zone 8 cooled by the 1st cooling zone 91 at 100 degreeC decreases. Accordingly, the cooling time of the entire heater 3 is shortened.

100: wafer
1: Wafer heating device
10: heater unit 10D: lower surface 10U: upper surface
11: cooling unit
2: Wafer holding plate
2D: Bottom 2U: Top
20: spot facing hole 25: temperature measuring element
3: Heater
3D: If
30: circuit pattern 31: base material
35: blind hole 36: third through hole
4: support plate
4D: If
45, 46: second through hole 45h: downward opening 45v: projection contour
5: cooling plate
5D: Bottom 5U: Top
50: body 51: upper layer
52, 53: recessed part 52b: bottom part 52h: opening 54: first recessed part
55, 56: first through hole 55h: upper opening
6: cooling stage 60: fixed shaft
7, 70: wiring 7c, 70c: middle part 71: first wiring
8: heating zone
9: cooling zone
91: first cooling zone 92: second cooling zone
93: third cooling zone 94: fourth cooling zone

Claims (9)

A heater unit comprising an upper surface on which a wafer is disposed and a heater for heating the wafer;
a cooling plate for cooling the heater unit;
and a wiring drawn out from the lower surface of the heater unit,
wherein the cooling plate is configured to be movable between a state in which an upper surface of the cooling plate is in contact with a lower surface of the heater unit and a state in which an upper surface of the cooling plate is separated from a lower surface of the heater unit. ,
The cooling plate includes a concave portion provided on an upper surface and a first through hole penetrating in a thickness direction from a position of a bottom portion of the concave portion;
The wiring is led out to the lower surface side of the cooling plate through the recess and the first through hole in a state in which the heater unit and the cooling plate are in contact with each other. According to claim 1, wherein a portion of the middle portion of the wiring is fixed to the lower surface of the heater unit,
The intermediate portion is disposed inside the concave portion in a state in which the heater unit and the cooling plate are in contact with each other. The wafer heating apparatus according to claim 2, wherein the first through hole is disposed below a location where the intermediate portion is fixed to the heater unit. The heater unit according to any one of claims 1 to 3, wherein the heater unit includes a support plate for supporting the heater from below;
the cooling plate is configured to be movable between a state in which an upper surface of the cooling plate is in contact with a lower surface of the support plate and a state in which an upper surface of the cooling plate is separated from a lower surface of the support plate;
The support plate is provided with a second through hole penetrating in the thickness direction,
The concave portion is provided such that a continuous space is formed between the upper opening of the first through hole and the lower opening of the second through hole in a state in which the support plate and the cooling plate are in contact;
The wiring is led out below the support plate through the second through hole. 5. The method according to claim 4, wherein at room temperature, the projection outline of the second through hole is located inside the outline of the opening of the concave portion;
and the projected contour is a contour obtained by projecting the contour of the lower opening onto the cooling plate. The method according to any one of claims 1 to 5, wherein the cooling plate includes a main body and an upper layer disposed on an upper surface of the main body;
The body is made of metal,
and the upper layer is made of a material different from that of the main body. According to any one of claims 1 to 6, wherein the heater is provided with a plurality of heating zones,
The upper surface of the cooling plate is provided with a plurality of cooling zones,
Each cooling zone is a virtual area corresponding to each heating zone,
A wafer heating apparatus, wherein an area (Sa) inside the outer peripheral line of each cooling zone and a contact area (Sb) with the heater unit in each cooling zone satisfy Sb/Sa≥0.5. The method according to claim 7, wherein the plurality of cooling zones include a first cooling zone having the largest Sb/Sa and a second cooling zone having the smallest Sb/Sa,
The difference between Sb/Sa in the first cooling zone and Sb/Sa in the second cooling zone is 0.35 or less. The method according to claim 7 or 8, wherein the plurality of cooling zones include a third and a fourth cooling zone adjacent to each other,
An area inside the outer circumferential line of the third cooling zone is smaller than an area inside the outer circumferential line of the fourth cooling zone,
The wiring includes a first wiring extending from the heating zone corresponding to the third cooling zone,
The concave portion includes a first concave portion corresponding to the first wiring,
and at least a part of the first concave portion is disposed in the fourth cooling zone.

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