JP2019062037A - Heating device - Google Patents

Abstract

To reduce time required for raising temperature of a holding surface of a heating device by a predetermined amount.SOLUTION: The heating device includes: a ceramic member having a substantially planar first surface substantially perpendicular to a first direction; and a heater disposed inside the ceramic member. The heater heats a target object disposed on the first surface of the ceramic member. Inside the ceramic member, in the direction substantially perpendicular to the first direction, there is a gap located between the ceramic portion forming the ceramic member and the heater.SELECTED DRAWING: Figure 4

Description

  The technology disclosed herein relates to a heating device.

  There is known a heating apparatus (also referred to as a "susceptor") that heats to a predetermined processing temperature (e.g., about 400 to 650C) while holding an object (e.g., a semiconductor wafer). The heating apparatus is used, for example, as a part of a semiconductor manufacturing apparatus such as a film forming apparatus (a CVD film forming apparatus or a sputtering film forming apparatus) or an etching apparatus (a plasma etching apparatus or the like).

  In general, the heating device includes a ceramic member having a holding surface and a heater disposed inside the ceramic member. When a voltage is applied to the heater, the heater generates heat, and an object (for example, a semiconductor wafer) held on the holding surface of the ceramic member is heated to, for example, about 400 to 650 ° C. (for example, Patent Documents 1 and 2) reference).

JP 10-242252 A JP, 2014-75525, A

  In recent years, there has been an increasing demand for shortening the time required to raise the temperature of the holding surface of the heating device by a predetermined temperature (hereinafter referred to as “the required time for temperature rise”) in order to increase the efficiency of the semiconductor manufacturing process. . Here, as the amount of heat (hereinafter referred to as “the amount of heat transfer in the vertical direction”) transmitted in the direction (hereinafter referred to as the “longitudinal direction”) from the heater to the holding surface increases, the required time for temperature rise decreases. Can be However, in general, the heater disposed inside the ceramic member is adjacent to the ceramic having a relatively high thermal conductivity not only in the direction orthogonal to the holding surface but also in the direction parallel to the holding surface. For this reason, not only in the longitudinal direction but also in a direction parallel to the holding surface (hereinafter referred to as "plane direction"), the amount of heat transfer in the longitudinal direction can not be sufficiently ensured by the amount of heat transfer from the heater. As a result, it may not be possible to shorten the time required for temperature rise.

  The present specification discloses a technology that can solve the above-described problems.

  The technology disclosed in the present specification can be realized, for example, as the following form.

(1) A heating device disclosed in the present specification includes a ceramic member having a substantially planar first surface substantially perpendicular to a first direction, and a heater disposed inside the ceramic member. A heating apparatus for heating an object disposed on the first surface of the ceramic member, wherein the ceramic member constitutes the ceramic member in a direction substantially perpendicular to the first direction inside the ceramic member. There is an air gap located between the part and the heater. In the heating device, inside the ceramic member, there is a gap located between the ceramic portion forming the ceramic member and the heater in a direction substantially perpendicular to the first direction (hereinafter, referred to as “planar direction”). doing. The thermal conductivity in the air gap is lower than the thermal conductivity of the ceramic portion. For this reason, in this heating device, the amount of heat transferred in the surface direction out of the total calorific value from the heater as compared to the conventional configuration in which no air gap exists between the ceramic portion and the heater in the surface direction The amount of heat transferred from the heater in the direction toward the holding surface (hereinafter referred to as the “longitudinal direction”) (hereinafter referred to as “the amount of heat transfer in the vertical direction”) ) Can be secured. As a result, according to the present heating device, the time required to raise the temperature of the holding surface (first surface) of the heating device by a predetermined temperature (hereinafter referred to as "the required time for temperature rise") Can be shortened.

(2) In the heating device, the plurality of gaps may be present at positions separated from each other along the heater between the heater and the ceramic portion. In the heating device, a plurality of air gaps are present at positions separated from each other between the heater and the ceramic portion. That is, in the plane direction, the air gap does not necessarily exist over the entire circumference of the heater, and a part of the heater is adjacent to the ceramic portion without the air gap. Since heat is transmitted not only in the longitudinal direction but also in the planar direction, in the present heating device, the temperature difference between the region corresponding to the heater and the region corresponding to the ceramic portion in the vicinity of the heater on the first surface Is suppressed. That is, according to the present heating device, the surface on the first surface is compared to the configuration in which the air gap exists over the entire circumference of the heater while shortening the time required for temperature rise compared to the conventional configuration. It is possible to improve the thermal uniformity in the direction.

(3) In the heating device, the air gaps may be present on both sides of the heater in at least one direction substantially perpendicular to the first direction. In the heating device, since the air gaps exist on both sides of the heater, the amount of heat transfer in the surface direction is suppressed on both sides of the heater. Thus, according to the heating device, it is possible to secure a larger amount of heat transfer in the vertical direction, as compared with the configuration in which the air gap exists only on one side of the heater.

(4) In the heating apparatus, the heater includes a linear heater portion extending in a linear shape, and the air gap is substantially perpendicular to the first direction and intersects the linear heater portion. The first air gap present on one side of the linear heater portion in the direction of movement and the second air gap present on the other side of the linear heater portion, the first air gap being Each of the second air gap and the second air gap may be configured to face the ceramic portion via the linear heater portion in the direction orthogonal to the linear heater portion. In the heating device, each of the first air gap and the second air gap located on each side of the linear heater portion is a ceramic portion through the linear heater portion in the direction orthogonal to the linear heater portion. It is opposite to. That is, the first air gap and the second air gap do not face each other in the direction orthogonal to the linear heater portion, and not at the positions facing the respective air gaps with the linear heater portion interposed therebetween. Ceramics exist. Here, in the portion where the air gaps are opposed to each other across the linear heater portion, the amount of heat transfer in the surface direction is suppressed on both sides of the linear heater portion. Therefore, the portion in which the ceramic portions are opposed to each other across the linear heater portion In particular, the temperature difference is large. Therefore, according to the heating device, the heat uniformity in the direction along the linear heater portion in the ceramic portion in the vicinity of the linear heater portion, as compared to the configuration in which all the gaps face each other with the linear heater portion interposed therebetween. It can improve.

(5) In the heating device, when the heater is virtually divided into a plurality of segments aligned in a direction substantially orthogonal to the first direction, at least a portion of the ceramic member is selected from the plurality of segments A first heater disposed in the first segment, and a second heater disposed in the second segment adjacent to the first segment, wherein the air gap is formed by It may be configured to be present on at least one of the mutually facing sides of the heater and the second heater. In the heating device, the air gap is present on at least one of the mutually opposing sides of the first heater and the second heater. Thereby, according to the heating device, the first segment and the second segment mutually affect each other thermally as compared with the configuration in which there is no gap between the first heater and the second heater. Can be suppressed.

  Note that the technology disclosed in the present specification can be realized in various forms, and for example, can be realized in the form of a holding device, a heating device, a component for a semiconductor manufacturing apparatus, a manufacturing method thereof, and the like. It is possible.

FIG. 1 is a perspective view schematically showing an appearance configuration of an electrostatic chuck 100 in an embodiment. It is an explanatory view showing roughly the XZ section composition of electrostatic zipper 100 in an embodiment. It is an explanatory view showing roughly the XY section composition of electrostatic zipper 100 in an embodiment. It is explanatory drawing which expands and shows the X1 part of the ceramic member 10 in FIG. It is explanatory drawing which expands and shows X2 part of the ceramic member 10 in FIG. It is explanatory drawing which shows typically the transfer of the heat from the heater electrode 50 in the patterns 1-4.

A. Embodiment:
A-1. Configuration of electrostatic chuck 100:
FIG. 1 is a perspective view schematically showing an appearance configuration of the electrostatic chuck 100 in the present embodiment, and FIG. 2 is an explanatory view schematically showing an XZ cross-sectional configuration of the electrostatic chuck 100 in the present embodiment. FIG. 3 is an explanatory view schematically showing an XY cross-sectional configuration of the electrostatic chuck 100 in the present embodiment. 2 shows the XZ cross-sectional configuration of the electrostatic chuck 100 at the position II-II in FIG. 3, and FIG. 3 shows the XY cross-sectional configuration of the electrostatic chuck 100 at the position III-III in FIG. It is shown. In each figure, mutually orthogonal XYZ axes for specifying the direction are shown. In this specification, for convenience, the positive direction of the Z-axis is referred to as the upward direction, and the negative direction of the Z-axis is referred to as the downward direction. However, the electrostatic chuck 100 is actually installed in an orientation different from such an orientation. It may be done. The vertical direction (Z-axis direction) corresponds to the first direction in the claims.

  The electrostatic chuck 100 is a device for attracting and holding an object (for example, the wafer W) by electrostatic attraction, and is used, for example, to fix the wafer W in a vacuum chamber of a semiconductor manufacturing apparatus. The electrostatic chuck 100 includes a ceramic member 10 and a base member 20 arranged in a predetermined arrangement direction (in the present embodiment, in the vertical direction (Z-axis direction)). The ceramic member 10 and the base member 20 are arranged such that the lower surface S2 (see FIG. 2) of the ceramic member 10 and the upper surface S3 of the base member 20 face each other in the arrangement direction. The electrostatic chuck 100 corresponds to the heating device in the claims.

  The ceramic member 10 is, for example, a plate member having a circular flat surface, and is formed of ceramic (for example, alumina, aluminum nitride, or the like). The diameter of the ceramic member 10 is, for example, about 50 mm to 500 mm (usually about 200 mm to 450 mm), and the thickness of the ceramic member 10 is, for example, about 1 mm to 10 mm.

  As shown in FIG. 2, a chuck electrode 40 formed of a conductive material (for example, tungsten, molybdenum or the like) is provided inside the ceramic member 10. The shape of the chuck electrode 40 in the Z-axis direction is, for example, substantially circular. When a voltage is applied to the chuck electrode 40 from a power supply (not shown), an electrostatic attractive force is generated, and the electrostatic attractive force causes the wafer W to face the surface of the ceramic member 10 opposite to the lower surface S2 Suction fixed on the surface S1 ′ ′). The suction surface S1 of the ceramic member 10 is a substantially planar surface substantially orthogonal to the above-described arrangement direction (Z-axis direction). The suction surface S1 of the ceramic member 10 corresponds to the first surface in the claims. Further, in the present specification, a direction substantially orthogonal to the Z axis (that is, a direction parallel to the suction surface S1) is referred to as a “plane direction”.

  As shown in FIG. 2 and FIG. 3, inside the ceramic member 10, there is provided a heater electrode 50 formed of a resistive heating element formed of a conductive material (for example, tungsten, molybdenum or the like). When a voltage is applied to the heater electrode 50 from a power source (not shown), the heater electrode 50 generates heat to warm the ceramic member 10, and the wafer W held by the suction surface S1 of the ceramic member 10 is warmed. Thereby, temperature control of the wafer W is realized. The heater electrode 50 corresponds to a heater in the claims.

  In the present embodiment, the heater electrode 50 includes the first heater 50L and the second heater 50R in order to control the temperature of the suction surface S1 of the ceramic member 10 with high accuracy. The first heater 50L and the second heater 50R are disposed independently of each other on one virtual plane (for example, the XY plane in FIG. 3) substantially orthogonal to the Z-axis direction. In other words, each heater 50L, 50R is disposed in each segment when virtually dividing at least a part of the ceramic member 10 into a plurality of segments (areas) aligned in a direction substantially orthogonal to the Z-axis direction. It is a heating resistor. As a setting mode of the segments, a mode in which all or part of the ceramic member 10 is divided into a plurality of segments SL and SR arranged in the circumferential direction centering on the center point of the suction surface S1 is used. Each of the heaters 50L and 50R includes an arc portion 50C having mutually different diameters and a straight portion 50D connecting the arc portions 50C, with the center point of the suction surface S1 as the center. According to such a configuration, temperature control can be performed for each of the segments SL and SR by individually controlling the heaters 50L and 50R disposed in each of the segments SL and SR. Temperature control of adsorption side S1 can be performed with sufficient accuracy. The arc portion 50C and the straight portion 50D correspond to the linear heater portion in the claims.

  The base member 20 is, for example, a circular flat plate member having the same diameter as the ceramic member 10 or a larger diameter than the ceramic member 10, and is formed of metal (aluminum, aluminum alloy, or the like). The diameter of the base member 20 is, for example, about 220 mm to 550 mm (usually, 220 mm to 470 mm), and the thickness of the base member 20 is, for example, about 20 mm to 40 mm.

  A refrigerant channel 21 is formed in the inside of the base member 20. When a refrigerant (for example, a fluorine-based inert liquid, water or the like) is allowed to flow through the refrigerant flow path 21, the base member 20 is cooled, and the transmission between the base member 20 and the ceramic member 10 via the adhesive layer 30 described later. The ceramic member 10 is cooled by the heat, and the wafer W held on the suction surface S1 of the ceramic member 10 is cooled. Thereby, temperature control of the wafer W is realized.

  The ceramic member 10 and the base member 20 are bonded to each other by an adhesive layer 30 disposed between the lower surface S2 of the ceramic member 10 and the upper surface S3 of the base member 20. The adhesive layer 30 is made of, for example, an adhesive such as silicone resin, acrylic resin, or epoxy resin. The thickness of the adhesive layer 30 is, for example, about 0.1 mm to 1 mm.

A-2. About the air gap P inside the base member 20:
4 is an explanatory view showing the X1 portion of the ceramic member 10 in FIG. 3 in an enlarged manner, and FIG. 5 is an explanatory view showing the X2 portion of the ceramic member 10 in FIG. As shown in FIGS. 4 and 5, a void P is present inside the ceramic member 10. The air gap P is located in the plane direction between the ceramic portion 11 constituting the ceramic member 10 and the heater electrode 50 (heaters 50L, 50R). In other words, the air gap P is adjacent to the heater electrode 50 in the plane direction (in the plane direction, the ceramic portion 11 is not interposed between the heater electrode 50 and the air gap P, and both are in direct contact Yes). Note that the air gap P may be adjacent to the heater electrode 50 on a virtual plane orthogonal to the Z-axis direction, or the heater may be on a plane inclined at an angle of ± 10 degrees or less with respect to the virtual plane. It may be adjacent to the electrode 50. Further, as shown in FIGS. 4 and 5, in the Z-axis direction, a part of the air gap P may overlap the peripheral portion of the heater electrode 50. Further, in the plane direction, a plurality of gaps P are present at positions separated from each other along the heater electrode 50 between the heater electrode 50 and the ceramic portion 11. In other words, the plurality of air gaps P are arranged along the side of the linear heater electrode 50 while being spaced apart from each other (discontinuously).

  Further, in the Z-axis direction, air gaps P are present on both sides in the direction intersecting the heater electrode 50. In FIG. 4, in the direction substantially perpendicular to the extending direction of the arc portion 50C of the heater electrode 50, the air gaps P1 and P2 are opposed to each other with the arc portion 50C interposed therebetween. In FIG. 5, the gaps P3 and P4 do not face each other in the direction substantially perpendicular to the extending direction of the arc portion 50C. Specifically, the air gap P3 adjacent to one side of the arc portion 50C corresponds to the ceramic portion 11 adjacent to the other side of the arc portion 50C in the direction substantially perpendicular to the arc portion 50C. Are facing each other. Further, the air gap P4 adjacent to the other side of the arc portion 50C faces the ceramic portion 11 adjacent to one side of the arc portion 50C in the direction substantially perpendicular to the arc portion 50C. ing. The air gaps P3 and P4 correspond to the first air gap and the second air gap in the claims.

  Further, as shown in FIG. 5, the linear portion 50D of the first heater 50L and the linear portion 50D of the second heater 50R are opposed in the surface direction (X-axis direction). A fifth air gap P5 is adjacent to the side of the straight portion 50D of the first heater 50L facing the second heater 50R. Further, the sixth air gap P6 is adjacent to the side of the straight portion 50D of the second heater 50R facing the first heater 50L. As shown in FIG. 5, the smaller the pitch between heater parts of heater electrode 50, the larger the number of gaps P adjacent to the heater part, or the length of one gap P may be longer. preferable. As a result, the amount of heat transfer in the surface direction is suppressed in the area where the heater portions are dense, and as a result, the area where the heater portions are dense can be suppressed from becoming hot compared to other areas.

A-3. Method of manufacturing electrostatic chuck 100:
An example of a method of manufacturing the electrostatic chuck 100 is as follows. First, the ceramic member 10 in which the above-mentioned air gap P exists inside is produced. A plurality of ceramic green sheets (for example, alumina green sheets) are prepared, and each ceramic green sheet is subjected to printing, drilling, etc. of metallized ink for forming the chuck electrode 40, the heater electrode 50, etc. The ceramic green sheets are laminated through an adhesive, thermocompression bonded, and cut into a predetermined disk shape. Thereby, a ceramic molded body is formed. Next, the ceramic molded body is fired to form the ceramic member 10.

  Here, for example, by adjusting at least one of the amount of adhesive applied between the ceramic green sheets, the magnitude of the pressure at the time of thermocompression bonding, and the pressing time at the time of thermocompression bonding, The ceramic member 10 in which the space | gap P exists can be produced. For example, as the amount of adhesive applied between the ceramic green sheets is reduced, the pressure at the time of thermocompression bonding is reduced, and the pressing time at the time of thermocompression bonding is shortened, the inside of the ceramic member 10 The air gap P is likely to be present.

  Next, the base member 20 is prepared. The base member 20 can be manufactured, for example, by a known manufacturing method. Next, the ceramic member 10 and the base member 20 are joined. Specifically, the lower surface S2 of the ceramic member 10 and the upper surface S3 of the base member 20 are opposed to each other, and the ceramic member 10 and the base member 20 are bonded by the adhesive layer 30. The above steps complete the manufacture of the electrostatic chuck 100 having the above-described configuration.

A-4. Effects of the present embodiment:
As described above, in the electrostatic chuck 100 of the present embodiment, the air gap P is present inside the ceramic member 10. The air gap P is located between the ceramic portion 11 constituting the ceramic member 10 and the heater electrode 50 in the plane direction. In general, the thermal conductivity (thermal conductivity of air) in the air gap P is lower than the thermal conductivity of the ceramic portion 11. Therefore, in the electrostatic chuck 100 of the present embodiment, compared to the conventional configuration in which the air gap P does not exist between the ceramic portion 11 and the heater electrode 50 in the surface direction, of the total heat generation amount from the heater electrode 50, The amount of heat transferred in the surface direction (hereinafter referred to as "the amount of heat transfer in the surface direction") is suppressed in the direction (hereinafter referred to as the "longitudinal direction") from the heater electrode 50 toward the adsorption surface S1. A large amount of heat (hereinafter referred to as “the amount of heat transfer in the vertical direction”) can be secured. As a result, according to the electrostatic chuck 100 of this embodiment, the time required to raise the temperature of the holding surface (the adsorption surface S1 of the electrostatic chuck 100) by a predetermined temperature (compared to the conventional configuration) Hereinafter, the “time required for temperature rise” can be shortened.

  Further, in the present embodiment, a plurality of air gaps P are present at positions separated from each other between the heater electrode 50 and the ceramic portion 11. That is, the air gap does not necessarily exist over the entire circumference of the heater electrode 50 in the plane direction, and a part of the heater electrode 50 is adjacent to the ceramic portion 11 without the air gap P. Therefore, in the present embodiment, in the suction surface S1 of the ceramic member 10, the temperature difference between the region immediately above the heater electrode 50 and the region immediately above the ceramic portion near the heater electrode 50 is suppressed. Ru. That is, according to the present embodiment, compared with the above-described conventional configuration, while achieving shortening of the temperature rise required time, compared with the configuration in which the air gap exists over the entire circumference of the heater electrode 50, It is possible to improve the thermal uniformity in the surface direction.

  Further, in the present embodiment, since the air gaps P exist on both sides of the heater electrode 50, the amount of heat transfer in the surface direction is suppressed on both sides of the heater electrode 50. Thus, according to the present embodiment, it is possible to secure a larger amount of heat transfer in the vertical direction, as compared with the configuration in which the air gaps are adjacent to only one side of the heater electrode 50.

  Further, in the present embodiment, each of the first gap P3 and the second gap P3 respectively located on both sides of the linear heater portion (for example, the heater electrode 50) of the heater electrode 50 is orthogonal to the linear heater portion. The ceramic portion 11 is opposed to the ceramic portion 11 through the linear heater portion. That is, the first air gap P3 and the second air gap P4 are not opposed to each other in the direction orthogonal to the linear heater portion, and are opposed to the air gaps P3 and P4 across the linear heater portion. There is not a void but a ceramic part 11 in the Here, since the heat transfer amount in the surface direction is suppressed on both sides of the linear heater portion, in the portions where the air gaps P oppose each other with the linear heater portion interposed, the ceramic portions 11 oppose each other via the linear heater portion. In particular, the temperature difference is large with respect to the Therefore, according to the present embodiment, it is possible to improve the thermal uniformity in the direction along the linear heater portion, as compared to the configuration in which all the gaps P oppose each other with the linear heater portion interposed therebetween.

  Further, in the present embodiment, the fifth gap P5 is adjacent to the side of the linear portion 50D of the first heater 50L, and the sixth side is the side of the linear portion 50D of the second heater 50R. The air gaps P6 are adjacent to each other. Thus, according to the present embodiment, the first segment SL and the second segment SR are thermally coupled to each other as compared with the configuration in which there is no gap between the first heater 50L and the second heater 50R. Influence each other. This is particularly effective when the first segment SL and the second segment SR are independently temperature-controlled as in the present embodiment.

  The details will be described below. FIG. 6 is an explanatory view schematically showing transfer of heat from the heater electrode 50 in the patterns 1 to 4. As shown in FIG. The XY cross-sectional structure of the ceramic member 10 of each pattern is schematically shown in the upper stage in FIG. 6, and the XZ cross-sectional structure of the ceramic member 10 of each pattern is schematically shown in the lower side. Although the patterns 1 to 4 are different from each other in specific configuration of the ceramic member, for convenience of explanation, the patterns 1 to 4 will be described with the same reference numerals. Further, of the pair of sides along the extension direction of the heater electrode 50 in the Z-axis direction, the side on one side (X-axis negative direction side) is referred to as the first side 52L, and the other side The side in the positive direction of the X-axis) is referred to as a second side 52R.

  As shown in FIG. 6, the pattern 1 is a comparative example in which no air gap exists between the heater electrode 50 and the ceramic portion 11 (in other words, no air gap is adjacent to the heater electrode 50). It corresponds to In the pattern 1, the heat uniformity on the suction surface S1 of the ceramic member 10 is the best “◎”, but the required time for temperature rise is long and the defect “x”. In the pattern 1, in the heater electrode 50, the ceramic portions 11 having relatively high thermal conductivity are adjacent in both the vertical direction (Z-axis positive direction) and the surface direction (X-axis direction). For this reason, a large amount of heat is transmitted from the heater electrode 50 not only in the vertical direction but also in the surface direction, and the amount of heat transfer in the vertical direction can not be sufficiently secured by that amount. It is considered to be.

  The pattern 2 is an embodiment in which the air gaps P exist on both sides of the heater electrode 50 in the surface direction (X-axis direction). Specifically, a plurality of first air gaps PL are adjacent to the first side 52L of the heater electrode 50, and the plurality of first air gaps PL are separated from each other, and the first side They are aligned along the side 52L. Further, a plurality of second gaps PR are adjacent to the second side 52R of the heater electrode 50, and the plurality of second gaps PR are separated from each other, and the second side 52R is formed. Side by side. Further, the first air gap PL and the second air gap PR are opposed to each other via the heater electrode 50 in a direction (X-axis direction) orthogonal to the heater electrode 50. There are almost no air gaps on the top surface of the heater electrode 50. In the pattern 2, the heat uniformity on the suction surface S1 of the ceramic member 10 is somewhat poor “Δ”, the required time for temperature rise is short, and it is good “o”.

  In the pattern 2, the air gaps PL and PR are adjacent to the heater electrode 50. Therefore, the amount of heat transferred from the heater electrode 50 in the surface direction (hereinafter referred to as "the amount of heat transfer in the surface direction") is smaller than in the pattern 1 where the air gap is not adjacent to the heater electrode 50. The amount of heat transferred from the electrode 50 in the longitudinal direction (hereinafter, referred to as “the amount of heat transfer in the longitudinal direction”) is large. As a result, in the second pattern, the required temperature rise time is considered to be shorter than in the first pattern. Further, in the pattern 2, the air gaps PL and PR are adjacent to both the first side 52L and the second side 52R of the heater electrode 50, respectively. Therefore, as compared with a configuration in which the air gaps PL and PR are adjacent to only one of the first side 52L and the second side 52R of the heater electrode 50, the first side 52L side of the heater electrode 50 is provided. Since a temperature difference between the ceramic portion 11 and the ceramic portion 11 on the side of the second side 52R is suppressed, the decrease in temperature uniformity on the adsorption surface S1 of the ceramic member 10 is suppressed.

  Pattern 3 is a point that the first air gap PL and the second air gap PR do not face each other via the heater electrode 50 in the direction (X-axis direction) orthogonal to the heater electrode 50 with respect to the pattern 2 Are different embodiments. That is, in the pattern 3, in the direction orthogonal to the heater electrode 50, the first air gap PL faces the ceramic portion 11 instead of the second air gap PR. In addition, the second air gap PR faces the ceramic portion 11 instead of the first air gap PL in the direction orthogonal to the heater electrode 50. In short, the heater electrode 50 is adjacent to the first air gap PL and not adjacent to the second air gap PR, and is adjacent to the second air gap PR and not adjacent to the first air gap PL. Are alternately arranged along the extension direction of the heater electrode 50. In the pattern 3, as in the pattern 2, the required time for temperature rise is short, and it is good "o". Moreover, in the pattern 3, compared with the pattern 2, the thermal uniformity in the adsorption surface S1 of the ceramic member 10 is good "(circle)".

  Here, in the portion where the first air gap PL and the second air gap PR are opposed to each other with the heater electrode 50 interposed therebetween, the amount of heat transfer in the surface direction is suppressed on both sides 52L and 52R of the heater electrode 50. The temperature difference is particularly large with respect to a portion where the portions 11 face each other with the heater electrode 50 interposed therebetween. On the other hand, in pattern 3, compared with pattern 2, the portion where the first air gap PL and the second air gap PR face each other with the heater electrode 50 interposed therebetween, and the ceramic portion 11 with the heater electrode 50 interposed therebetween. There are few opposing parts. Therefore, according to the pattern 3, compared to the pattern 2, it is possible to improve the thermal uniformity in the direction along the heater electrode 50 in the ceramic portion 11 near the heater electrode 50.

  The pattern 4 is a comparative example in which the air gaps PL and PR exist inside the ceramic member 10 but none of the air gaps PL and PR is adjacent to the heater electrode 50 in the ceramic member 10. In the pattern 4, although the heat uniformity on the suction surface S1 of the ceramic member 10 is somewhat poor "Δ", the required time for temperature rise is long and the defect is "x". In pattern 4, as in pattern 1, heater electrode 50 is adjacent to ceramic portion 11 having a relatively high thermal conductivity in both the vertical direction (Z-axis positive direction) and the plane direction (X-axis direction). ing. For this reason, a large amount of heat is transmitted from the heater electrode 50 not only in the vertical direction but also in the surface direction, and the amount of heat transfer in the vertical direction can not be sufficiently secured by that amount. It is considered to be. Further, since the air gaps PL and PR having relatively low thermal conductivity exist at positions away from the heater electrode 50, in particular, the portion where the air gaps PL and PR exist has a lower temperature than the other portions. As a result, it is considered that the temperature uniformity on the suction surface S1 of the ceramic member 10 is reduced.

B. Modification:
The technology disclosed in the present specification is not limited to the above-described embodiment, and can be modified into various forms without departing from the scope of the present invention. For example, the following modifications are also possible.

  The configuration of the electrostatic chuck 100 in each of the above embodiments is merely an example, and various modifications are possible. For example, although the heater electrode 50 including the first heater 50L and the second heater 50R is illustrated as a heater in the above embodiment, the present invention is not limited to this, and a heating resistance connected continuously on a virtual surface It may be a body, or it may include three or more heating resistors arranged in each of three or more segments.

  Further, in the above embodiment, the plurality of air gaps P are present at positions separated from each other along the heater electrode 50 between the heater electrode 50 and the ceramic portion 11 in the plane direction, but the present invention is limited thereto Alternatively, an integral air gap extending continuously along the entire length of the heater electrode 50 may be present between the heater electrode 50 and the ceramic portion 11. In the above embodiment, the air gap P is present on each side of the heater electrode 50 in the Z-axis direction, but the present invention is not limited to this. An air gap P may be present only on the side.

  Further, in the above embodiment, the fifth air gap P5 may not be adjacent to the side of the linear portion 50D of the first heater 50L, and the side of the linear portion 50D of the second heater 50R. The sixth air gap P6 may not be adjacent to the second air gap. In short, the air gap P may be present in at least one of the mutually opposing sides of the first heater 50L and the second heater 50R adjacent to each other.

  In the above embodiment, the ceramic member 10 and the base member 20 may be joined not by the integral adhesive layer 30 but by a plurality of joint portions. Specifically, between the ceramic member 10 and the base member 20, a plurality of bonding portions disposed discretely on one virtual plane orthogonal to the opposing direction of the ceramic member 10 and the base member 20 are formed. It may be

  In each of the above embodiments, the single electrode system in which one chuck electrode 40 is provided inside the ceramic member 10 is adopted, but the bipolar system in which a pair of chuck electrodes 40 is provided inside the ceramic member 10 May be employed. Moreover, the material which forms each member in the electrostatic chuck 100 of each said embodiment is an illustration to the last, and each member may be formed with another material.

  Moreover, the manufacturing method of the electrostatic chuck 100 in each said embodiment is an example to the last, and can be variously deformed. For example, as a method for producing the ceramic member 10 in which the air gap P exists inside, a recess that becomes the air gap P after firing is formed on the periphery of the metallized ink for forming the heater electrode 50 printed on the ceramic green sheet. Alternatively, a method of forming a recess that will become the void P after firing may be employed in the adhesive (adhesive layer) applied to the ceramic green sheet before lamination.

  The present invention is not limited to the electrostatic chuck 100 that holds the wafer W using electrostatic attraction, and includes other ceramic members in which a heater is disposed, and other heating devices that hold an object on the surface of the ceramic member. It is applicable also to an apparatus (for example, a vacuum chuck, a heater, etc.).

10: ceramic member 11: ceramic portion 20: base member 21: refrigerant flow path 30: adhesive layer 40: chuck electrode 50: heater electrode 50C: arc portion 50D: straight portion 50L: first heater 50R: second heater 52L , 52R: side 100: electrostatic chuck P (P1 to P6, PL, PR): air gap S1: suction surface S2: lower surface S3: upper surface SL: first segment SR: second segment W: wafer

Claims (5)

A ceramic member having a substantially planar first surface substantially perpendicular to the first direction;
A heater disposed inside the ceramic member;
A heating device for heating an object disposed on the first surface of the ceramic member,
In the inside of the ceramic member, in the direction substantially perpendicular to the first direction, there is a gap located between the ceramic portion forming the ceramic member and the heater. apparatus. In the heating device according to claim 1,
The heating device, wherein the plurality of air gaps are present at mutually spaced positions along the heater between the heater and the ceramic portion. In the heating device according to claim 1 or 2,
The heating device, wherein the air gap is present on both sides of the heater in at least one direction substantially perpendicular to the first direction. In the heating device according to claim 3,
The heater includes a linear heater portion extending linearly,
The air gap is substantially perpendicular to the first direction, and a first air gap existing on one side of the linear heater portion in a direction intersecting the linear heater portion, and the linear heater portion And a second void present on the other side of the
Each of the first air gap and the second air gap is characterized by being opposed to the ceramic portion via the linear heater portion in a direction orthogonal to the linear heater portion. Heating device. The heating device according to any one of claims 1 to 4.
The heater is disposed in a first segment of the plurality of segments when at least a portion of the ceramic member is virtually divided into a plurality of segments aligned in a direction substantially orthogonal to the first direction. A first heater, and a second heater disposed in a second segment adjacent to the first segment,
The heating device, wherein the air gap is present in at least one of opposing sides of the first heater and the second heater.

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