JP6555922B2 - Heating device - Google Patents

Description

  The present invention relates to a heating apparatus used for heating an object to be processed to a predetermined temperature in semiconductor manufacturing or plasma processing.

  In order to process a film to be heated (hereinafter, also simply referred to as a substrate) to be heated such as a semiconductor wafer in semiconductor manufacturing, plasma processing, or the like, in a processing chamber, It is extremely important to control the temperature of the substrate, which is a heated object, to a predetermined temperature and maintain the entire surface at a constant temperature. For such temperature control, in these manufacturing and processing, a heating plate having a heating area composed of a flat surface for heating an object to be heated in contact with the heating area, and heating for heating the heating area. A heating device (planar heater) including a body (heater) is used. As a result, the substrate is placed on the surface of the heating plate, brought into contact therewith, and uniformly heated, and a predetermined processing is performed.

  In such a heating apparatus, it is important to maintain the entire substrate (the entire surface) at a constant temperature with high accuracy, and thus the entire heating region on the surface of the heating plate (hereinafter, also simply referred to as a plate). Various proposals have been made (for example, Patent Document 1). In the heating device of Patent Document 1, four heating elements (heating bodies) arranged along the surface of the heating plate (plate-like member), power supply means to them, and any one of them It is provided with connection state changing means for changing the connection state to serial connection and parallel connection, respectively. By this changing means, the amount of heating to the object to be heated is based on the surface temperature based on the temperature of the heating element detected by the temperature detecting means. A technique of changing the connection state so as to be uniform is disclosed. Then, there is exemplified one in which each heating element formed in a U shape in a plan view, a single wire (resistance heating element) is disposed so as to extend along the surface of the heating plate, A technique for heating an object to be heated placed on the same plate based on the arrangement and connection state changing means of each heating element is disclosed.

JP 2012-89653 A

  In the heating device of Patent Document 1, a plurality of U-shaped heating elements are arranged in parallel to each other on heating elements (resistance heating elements) arranged along the surface of the heating plate. Since each such heat generating element (line) has a long U-shaped linear leg portion, unevenness in heat generation occurs in a portion along the longitudinal direction due to variations in characteristics such as resistance along the longitudinal direction. For this reason, even if the connection state is changed, due to the occurrence of non-uniformity of heat generation (heat generation unevenness) in the longitudinal direction of the resistance heating element (line), the longitudinal direction that the heating element takes charge also on the surface of the heating plate The temperature unevenness occurs at the site corresponding to. Such temperature unevenness occurs in each part of the surface of the heating plate that each heating element is responsible for, so when looking at the entire surface, there is a width (deviation) in the temperature due to the temperature unevenness. As a result, the substrate mounted on the surface and heated is also uneven in temperature.

  On the other hand, recently, in the processing of a semiconductor substrate, the temperature variation (temperature distribution) range allowed on the entire surface of the substrate is, for example, a target temperature based on a request based on the processing performance or processing accuracy. Demands such as within ± 1 degree or within ± 0.5 degree are becoming increasingly strict. Therefore, the above-described heating apparatus may not be able to meet the demand due to the occurrence of the temperature unevenness. Moreover, even when the object to be heated is heated by such a heating device, the target temperature to be heated varies slightly depending on the object to be heated, for example, within a range of 300 ° C to 500 ° C. For this reason, in a specific temperature range within such a temperature range, even if it can be maintained at a constant temperature within a range where temperature unevenness is also allowed, it may not be maintained in other temperature ranges.

  And in each part in the plate for heating itself and the planar expansion, there exists a difference in heat dissipation (heat transferability) on the structure. For example, the heat dissipation property is low at the central portion of the plate corresponding to the plurality of resistance heating elements (groups), but the heat dissipation property is relatively high at the outer edge portion. Therefore, even if it can be maintained at the target temperature at the central portion, it may not be easy to maintain the target temperature at the outer edge portion, and it is easy to maintain the entire surface of the plate (entire surface) at a constant temperature. Not. Furthermore, in such a heating apparatus, an unspecified part of the heating plate may deviate from the target temperature due to changes in various conditions such as the heating plate.

  The present invention has been made in view of the above problems as in the conventional heating device described above, and the temperature of the surface of the heating plate is adjusted to the heating region (object to be heated) without incurring the complexity of the structure. It is an object of the present invention to provide a heating device capable of maintaining a constant target temperature without temperature unevenness over the entire contact surface area.

The present invention according to claim 1 is a heating device comprising a heating plate having a flat surface for contacting and heating an object to be heated, and a heating body for heating the surface,
For the heating element, a number of heating elements provided with end portions of resistance heating elements that generate heat when energized are used,
In many places set to be scattered on the back surface of the heating plate, the end portions of the plurality of heating bodies are provided with concave portions formed by circular holes that are fitted by gap fitting. The multiple heating elements are provided on the back side of the heating plate so that the multiple portions are heated by being fitted into the recesses and brought into contact with each other.
According to the second aspect of the present invention, a large number of locations scattered and set on the back surface of the heating plate are in the contact surface area of the object to be heated on the front surface of the back surface of the heating plate. The heating device according to claim 1, wherein the heating device is a large number of locations that are scattered and set within a surrounding region that surrounds and includes a corresponding region.

The present invention according to claim 3 is a heating apparatus comprising a heating plate having a flat surface for contacting and heating a circular object to be heated, and a heating body for heating the surface. ,
For the heating element, a number of heating elements provided with end portions of resistance heating elements that generate heat when energized are used,
Among the back surface of the heating plate, in a number of locations set to be scattered in surrounding regions including and surrounding a region corresponding to a circular contact surface region with the object to be heated on the front surface , A recessed portion into which the end portion of a large number of heating bodies can be fitted is provided, and the end portion is fitted into the recessed portion and is in contact with the back surface . The heating elements are provided on the back side of the heating plate so as to be heated, and the contact surface area is scattered on the front surface and the surrounding area is scattered on the surrounding area. A circumferential groove that is concentric with the contact surface region is cut into both the front and back surfaces of the heating plate so as to surround all of the many portions set in this manner.

The present invention described in claim 4, the contact of the end, any one of claims 1 to 3 for each heating body, characterized in that it is elastically pressed against pressed toward the back It is a heating apparatus as described in above.
According to the fifth aspect of the present invention, among the multiple locations, the interval between the adjacent locations located on the outermost side of the location group is smaller than the interval between the adjacent locations at other positions. The heating device according to any one of claims 1 to 4 , wherein the heating device is provided.
According to a sixth aspect of the present invention, the heating body is a rod-shaped body, and the resistance heating element is provided at an end portion of the rod-shaped body, and the heating body is a back surface of the heating plate. On the other hand, the heating device according to any one of claims 1 to 5 , wherein the heating device is provided in a substantially vertical state.

According to a seventh aspect of the present invention, the heating device includes a base member and a support column erected on the base member, and the heating plate is detachably attached to the upper end side of the support column. and, the plurality of heating bodies, wherein the base member to be held is positioned at the recess or the through hole provided separately, claim, characterized in that provided in the above the end 6 It is a heating apparatus as described in above.
According to an eighth aspect of the present invention, in the heating apparatus according to the seventh aspect , an intermediate plate is provided between the base member and the heating plate so as to be substantially parallel to the heating plate. And the plurality of heating bodies are provided in such a state that the positioning holes provided individually in the intermediate plate pass through the upper and lower intermediate portions of the respective heating bodies. It is the heating apparatus characterized.

  In the heating device of the present invention, as in the prior art, the resistance heating element in one heating element is not provided in an arrangement that extends long along the surface of the heating plate. That is, in the heating device of the present invention, as in the above configuration, a large number of heating bodies are set to be scattered on the back surface of the heating plate with the respective end portions (hereinafter also simply referred to as end portions). In addition, it is provided on the back surface side so as to heat each of a number of locations (hereinafter also simply referred to as locations). In the case of using a conventional heating element, the heating plate is uneven due to variations in characteristics such as resistance along the longitudinal direction due to variations in the longitudinal direction of the resistance heating element (line). Even on the surface, temperature unevenness occurs at a portion corresponding to the longitudinal direction of the heating element.

  On the other hand, in the case of using a heating element provided at the end of the resistance heating element that generates heat as in the present invention, the resistance heating element does not extend long along the surface of the plate. There is no uneven heat generation in the direction extending along. That is, the range in which the end of each heating element used in the present invention is heated is a narrow spot (spot part) scattered on the plate, so that there is no variation in the heating temperature in that part. Therefore, with respect to each heating element provided at a number of locations set in a scattered manner, the heating temperature of the resistance heating element at the end thereof is controlled to the target temperature (set temperature), so that the surface of the heating plate The temperature in the entire predetermined area can be maintained at a constant temperature (temperature management) with a high degree of uniformity. In addition, you may make the said many places scattered not only regularly but irregularly. And according to the difference in heat dissipation at each part of the plate, for example, when the heat dissipation (coldness) is relatively high, when the part near the outer peripheral edge of the plate is to be heated at a relatively high temperature, the specific part is selectively Adjustment and holding at a desired temperature can be easily performed by controlling the temperature of the heating body at the site.

  As described above, according to the heating apparatus of the present invention, the surface temperature of the heating plate can be easily set to a desired target temperature without temperature unevenness in the entire heating region (contact surface region of the object to be heated). Therefore, the temperature of the object to be heated can be easily and rationally controlled at a desired temperature. In the heating apparatus of the present invention, the number of heating elements is as large as possible, and it can be said that the distance between the locations for the arrangement is preferably as small as possible. However, the size of the heating plate and the surface of the object to be heated are not limited. Based on the size and shape of the contact surface area, it may be adjusted and set in consideration of the range in which the end of one heating body is responsible for heating so that a desired temperature can be obtained for the object to be heated. And in this invention, many places set to be scattered on the back surface of the heating plate are to be heated on the surface of the plate on which the object to be heated is placed among the back surface of the heating plate. Although it may be only an area corresponding to the contact surface area of the object, it may be as described in claim 2. In other words, the numerous locations may be numerous locations that are interspersed and set within an enclosed region that surrounds and includes a region corresponding to the contact surface region of the object to be heated on the surface. By including the inside of the surrounding area in this way, the temperature control of the contact surface area can be performed with higher accuracy and ease.

Also in the invention described in claim 3, of the back surface of the Plate, and the point where the respective said end portions are in contact, it is provided with recess capable fitted is the end portion, the end portion since that is the one that contacts the back surface fits in the recess, not only heat transfer rate is increased, stability of the position of the end portion of the heating member (positioning) is also obtained. For this reason, the heating location is also stable, and the heating conditions can be easily reproduced even when the plate is replaced with another plate having the same structure. In addition, there is no restriction | limiting in the edge part (end surface) of many heating bodies used for the heating apparatus of this invention, Although a plane may be sufficient, the hemispherical thing made into a convex is good. This is because the temperature unevenness can be further reduced because heat transfer is performed by contact in a narrow range close to point contact. However, in the case of a hemispherical shape that is convex, the bottom of the recess is preferably a conical or truncated conical hole toward the bottom (back) side. In this way, the position of the end portion in the recess is stabilized, and the contact area is increased in a narrow range compared to contact (point contact) when the bottom of the recess is flat. This is because the thermal conductivity is improved.

And when making the said edge part contact the said back surface in this way, it is good to set it as the pressure contact which presses each heating body toward the said back surface like Claim 4 . The position of the end portion of the heating body is slightly displaced due to a difference in thermal expansion of each member (component member) constituting each heating body during the heating process. In addition, the position of the end of the heating element is slightly different depending on the existence of dimensional tolerances and errors in the heating element itself, its manufacture, assembly, and assembling or mounting this as a heating device. There is. On the other hand, by using an elastic member such as a spring and pressing the respective heating elements elastically against the back surface by the spring force, even if such displacement occurs, the contact is stabilized. It is because it can be obtained.

  Among a number of locations on the back surface to be heated at the end, the distance between the adjacent locations located on the outermost side of the number of locations is greater than the spacing between the locations adjacent to each other at other positions. It is better to make it smaller. This is because a portion near the center of the plate where the many portions are concentrated also concentrates the heating portions, so the heat dissipation is low, and the temperature between the portions is easily kept constant. Therefore, the interval between the locations in the central portion can be set appropriately in relation to the heating region that is handled by the end of each heating element, so that the temperature in the region can be made uniform. On the other hand, as described above, the portion near the outer peripheral edge of the heating plate also has high heat dissipation (cooling performance), and therefore, adjacent to the outermost portion of the group of portions near the center and near the center. This is because the heating efficiency is better at the portion.

  For example, if the heating plate is circular and the object to be heated is also circular (disc), a plurality of concentric circles with the center of the heating plate as the base point are drawn, and a plurality of them are equiangularly spaced on each circumference. When the location (the center of the location) is set, it is preferable to reduce the angular interval toward the outer circumference or the outermost circumference. In addition, even when the plate is square (square or rectangular), if the object to be heated is circular, it may be the same as described above. For example, a predetermined (constant) length or width of the plate may be used. You may arrange | position by space | interval and may make only the space | interval of this location adjacent to the outermost location of many location groups small. In short, in the present invention, the arrangement of the locations may be determined so that the contact surface region of the object to be heated can be heated to a uniform temperature and the surface temperature of the region can be easily maintained at a desired temperature.

The heating element used in the heating device of the present invention has a resistance heating element that generates heat when energized at its end, and as described above, each part on the back surface of the plate with its respective end. As long as it is provided, a large number may be provided on the back side of the heating element, and the shape and structure of the heating element itself are not particularly limited. However, as in the sixth aspect of the present invention, it is preferable that a rod-shaped body is formed, and the heating body is provided so as to be substantially perpendicular to the back surface of the heating plate. This is because a large number of heating elements can be used, and the installation of the heating elements with a high degree of freedom can be achieved, for example, the installation interval between the heating elements can be reduced.

And, as described above, the heating device in the case of providing the heating body as a rod-like body in a state of being substantially perpendicular to the back surface of the plate is configured as in the invention according to claim 7. Good. In this case, as in the invention described in claim 8 , an intermediate plate is provided between the base member and the heating plate so as to be substantially parallel to the heating plate, The plurality of heating bodies may be provided so as to pass through positioning holes provided individually in the intermediate plate, and the upper and lower intermediate portions of each heating body are positioned in the positioning holes. . Although these will be described in detail in the embodiment, by providing such an intermediate plate, even if the heating plate is removed for replacement, an arrangement of a large number of heating elements is provided for the amount of the intermediate plate. Since the state can be maintained as it is, the replacement work is easy and convenient. This is because when there is no intermediate plate and the heating plate is removed, the upper end (end portion) of the heating body is in a free end state, so that it is easily inclined or laterally displaced. For this reason, after that, when another heating plate is attached, a displacement or a cruciform easily occurs at a position where the end portion is to be heated, and the heating condition may be changed. On the other hand, when there is an intermediate plate, it is easy to avoid these problems. In order to avoid such displacement, the intermediate plate may be a lattice-structured plate. However, by using a solid plate, heat generated from the end can be cut off. It is also possible to protect electrical wiring and the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially omitted perspective sectional view for explaining an embodiment in which the heating device of the present invention is embodied. The heating apparatus of FIG. 1 WHEREIN: Only one heating body is shown in figure, the center longitudinal cross-sectional front view which abbreviate | omits another heating body, and a principal part enlarged view. It is the figure which looked at the base member which comprises the heating apparatus of FIG. 1 from the top (upper part of FIG. 2), Comprising: The figure explaining the planar layout (arrangement) of a heating body. The figure explaining the plane layout of the location (heating location) where the edge part of a heating body is located in the heating plate which comprises the heating apparatus of FIG. The figure explaining the heating body with a holder before assembling as a heating apparatus. The figure explaining another example of the plane layout of the location (heating location) where the edge part of a heating body is located in the heating plate. The figure explaining the plane layout of the location (heating location) where the edge part of a heating body is located in a square heating plate.

  The embodiment which actualized the heating apparatus of this invention is described in detail based on FIGS. In the figure, reference numeral 100 denotes a heating device of this example (hereinafter also referred to as this example device). In this example, a flat surface is formed on a portion near the outer periphery of a circular base member 10 having a constant thickness on its own concentric circle. As seen, four columns (legs) 20 are arranged in an upright shape at equal angular intervals of 90 degrees, and a circular heating plate 30 having a constant thickness is formed at the upper end of each column 20. The base member 10 is attached in a concentric arrangement. Although details will be described later, the base member (circular plate) 10 is provided with a plurality of through-holes (hereinafter referred to as through-holes for heating body attachment) 13 having the same diameter for attaching the heating body in a predetermined arrangement over the entire area thereof. The same heating body 50 is attached to each hole in a fitting state. The apparatus 100 of this example is configured as described below in detail with the base member 10, the support 20, the heating plate 30, and the heating body 50 as main components. Hereinafter, description will be made sequentially.

  The support column 20 is a concentric, three-stage columnar cylinder with a small diameter on the upper side, and the base member 10 is located in the middle of each support column 20 via a mounting hole 15 provided at a predetermined position near the outer periphery thereof. It is provided so as to be supported by an upper end surface (annular surface) 23 of the large diameter portion 22 that penetrates the diameter portion 24 and forms a boundary with the large diameter portion 22 below. In this example, the through hole (circular hole) 13 for attaching the heating body provided in the base member 10 is formed between the center (center) of the base member (circular plate) 10 and the base member as shown in FIG. In each of a plurality of circumferences (upper) E1 and E2 concentrically arranged with 10 itself, the centers are provided so as to be scattered in a large number (21 locations in the figure) at substantially equal intervals in the circumferential direction. In addition, the large number of through holes 13 for attaching the heating bodies are set so that the adjacent ones are substantially equidistant, and the center of the through holes 13 for attaching the heating bodies is the base member (circular shape). Plate) is set to be regularly scattered over substantially the entire surface (entire area) excluding the portion near the outer periphery of 10. And in this example, the heating body 50 which makes a long rod-like body up and down is inserted in each through-hole 13 for attaching this heating body, and is positioned and held so as to be perpendicular to the base member 10 respectively. (See FIGS. 1 and 2). Details of this will be described later.

  On the other hand, the circular heating plate 30 is attached in a concentric arrangement with the base member 10 at the upper end of the small-diameter portion 26 of each support column 20, as described above. Bolts 60 are passed through bolt holes 32 provided at the same position in the radial direction near the outer periphery, and screwed into screw holes 29 provided at the center of the upper end surface of each column 20 to be fixed. (Removal, installation) is free. In the present example, the plate 30 is sandwiched between ceramic washer 65 disposed between the upper end surface of each support column 20 and the head of the bolt 60 so as to insulate the plate 30 from heat. Such a heating plate 30 has a surface (upper surface in the figure) 33 that is finished to a flat surface (planar surface) for mounting and heating the substrate K, which is an object to be heated, such as aluminum. It is made of alloy.

  And, in the back surface (lower surface in the drawing) 34 of the heating plate 30, the same location corresponding to the center of the numerous heating body mounting through holes 13 provided in a scattered manner in the base member 10 in plan view. However, it is set as a location (heating location) to be heated by a number of heating elements 50 described later. That is, this heating location is concentric with the center of the heating plate 30 and the heating plate 30 itself, as shown by the hatched small circles in FIG. In each of a plurality of circumferences (upper) E1 and E2 of the diameter, the centers are set so as to be scattered in a large number (in the figure, E1 is 8 locations, E2 is 12 locations) at substantially equal intervals in the circumferential direction. ing. And in this example, those many places (heating places) are set so that those adjacent to each other are substantially equidistant, and the portions near the outer periphery of the heating plate (circular plate) 30 It is set to be regularly scattered over the entire surface (the entire area) (see FIG. 4).

Each heating body 50 is in contact with each heating location on the back surface 34 of the heating plate 30 to heat. Moreover, each heating location is provided with a recess (circular hole with a predetermined depth) 37 into which an end 51 provided with a resistance heating element that generates heat when energized is provided. The end portion 51 of the heating body 50 is set so as to be fitted into the concave portion 37 and contact the back surface 34 thereof. In this example, the locations (small circles with hatching in FIG. 4) that are set to be scattered on the back surface 34 are positions where the concave portions 37 are provided. In addition, the bottom face (ceiling surface) 37b of this recessed part (hole) 37 has comprised the conical surface which becomes a concave in this example (refer the enlarged view in FIG. 2). In this example, the inside of a circle T indicated by a two-dot chain line in FIG. 4 is a region corresponding to the contact surface region of the object to be heated (circular substrate) K on the surface 33. Therefore, in this example, the heating locations are scattered and set so as to surround and include this circle, that is, the contact surface region T. In addition, a circumferential groove 39 is cut into a concentric circle with the plate 30 at the same position inside the uppermost surface of the support column 20 outside the outermost heating portion of the front and back surfaces of the plate 30. Yes. Thereby, each heating location, ie, each recessed part 37, is provided so that it may be scattered inside this circumferential groove 39, as shown in FIGS. Since the heat transfer area inside and outside of the circumferential groove 39 is reduced by the circumferential groove 39, heat radiation to the outside of the circumferential groove 39 is prevented.

  Next, a number of heating elements 50 used in the apparatus 100 will be described. However, each of the heating elements 50 has the same configuration, and each end 51 thereof is fitted in each recess 37 with the same configuration. However, for ease of explanation, Of the example devices 100, one (or two) of them are shown and the others are omitted. The entire heating body 50 is elongated in the vertical direction, and is illustrated (FIGS. 1 and 2), and has a rod-like body having a different diameter cylindrical shape (circular shaft shape) with a narrow upper end 51 and a lower end. . The heating body 50 includes a metallic cylindrical main body (cylindrical main body) 53, a current-carrying member (not shown) disposed therein, and the tip of the cylindrical main body 53 (FIG. 1, FIG. 2, 5 is formed of a small-diameter heating shaft portion 55 or the like projecting upward (in the upper side of FIG. 5). Is provided (see FIG. 5). The heating shaft 55 is slightly smaller than the inner diameter of the recess 37 so that the outer diameter of the tip forming the end 51 is fitted into the recess (circular hole) 37 provided on the back surface 34 of the plate 30 with a clearance fit. It has been made smaller. The heating shaft portion 55 is made of, for example, an insulator (ceramic), and the resistance heating element (for example, conductive ceramic) 57 is embedded as a U-shape, for example, as shown in the enlarged view of FIG. It is provided in a shape and generates heat when voltage is applied, and the end (upper end) 51 of the heating shaft 55 is concentrated to generate heat. In this example, the end portion 51 of the heating shaft portion 55 is formed in a convex hemispherical surface. Such a heating body 50 may be positioned and held by direct insertion or the like with respect to the heating body mounting through-hole 13 provided in the base member 10. The positioning and holding are performed as described above.

  Incidentally, the heating element 50 used in the apparatus 100 of this example is a known glow plug used by being screwed into a plug hole (screw hole) provided in the engine head in order to promote ignition of the diesel engine. Is the same. This is a heater that can heat the end 51 of the heating shaft 55 to an instantaneously high temperature, and is convenient because it can be obtained relatively easily. In this example, the structure is called a ceramic glow plug, but the heating shaft portion 55 is made of a metal pipe with a closed end portion, and a resistance heating element is arranged in the tip thereof while maintaining insulation. A known metal glow plug can also be used in the same manner. Each of them is an elongated rod-like body, and is suitable for application to the heating device of the present invention.

  In this example, such a heating body 50 is provided on the base member 10 using a holder 70 as described below. That is, a sheath tubular holder having a cylindrical barrel body 72 whose outer diameter is slightly smaller than the inner diameter of the through hole 13 for attaching the heating body in the base member 10, and a circular flange 74 projecting outward on the outer peripheral surface of the upper end thereof. 70, the heating body 50 is inserted into the holder 70 and fixed (see FIG. 5), and the fixed state is inserted into the through hole 13 for mounting the heating body, positioned and held. Yes. In addition, since the heating body 50 used in this example includes a screw (screw for screwing into a plug hole in a glow plug) 53b on the outer peripheral surface of the cylindrical main body 53, the inner surface of the holder 70 is also provided. A screw 73b is provided and fixed by a screwing method using this (see FIG. 5). In this example, in this fixed state, the holder 70 is inserted from above the base member 10 into the through hole 13 for attachment of the heating body through the cylindrical body part 72 with a small gap. Thus, all the heating elements 50 are positioned and held via the holder 70. In this holding state, the heating plate 30 is attached to the upper end of the support column 20, so that the end portion 51, which is the tip of the heating shaft portion 55 in the heating body 50, is a recess provided on the back surface 34 of the plate 30. 37 is set to fit.

  However, in this example, a coil spring 80 that is compressed up and down with an appropriate strength is mounted on the outer peripheral surface of the holder 70 between the lower surface of the upper flange 74 and the upper surface of the base member 10. The heating body 50 is pushed upward together with the holder 70 by the coil spring 80, and the end portion 51 of the heating shaft portion 55 is elastically pressed against the back surface 34 of the plate 30. That is, the end portion (the tip end of the heating shaft portion 55) 51 of the heating body 50 is elastically pushed into the concave portion 37, and is the back surface 34 of the plate 30, and is brought into pressure contact with the bottom surface (ceiling surface) 37b of the concave portion 37. (See FIG. 2). At this time, in this example, the end 51 is a hemispherical surface that is convex, and the bottom surface 37b of the concave portion 37 is a conical surface that is concave, so that the contact (pressure contact) is annular.

  In the apparatus 100 of this example, an intermediate plate (circular plate) 90 is provided between the base member 10 and the heating plate 30 so as to be substantially parallel to the heating plate 30. However, the intermediate plate 90 has a cylindrical body in the heating body 50 in the same arrangement as that of the recess 37 provided on the back surface 34 of the heating plate 30 and the heating body mounting through hole 13 of the base member 10. A large number of positioning holes 93 through which a portion near the tip of 53 can penetrate with a minute gap are provided. Thereby, each heating body 50 penetrates this positioning hole 93 in the site | part near the front-end | tip of the cylindrical main body 53, and is positioned and hold | maintained in the internal peripheral surface. The intermediate plate 90 passes through the small-diameter portion 26 at the upper end of each support column 20 through an attachment hole 95 provided at a predetermined position near the outer periphery before the heating plate 30 is attached. It is provided so as to be supported by the upper end surface (annular surface) 25 of the medium diameter portion 24. Accordingly, even when the heating plate 30 is removed in the replacement of the heating plate 30, the displacement of the heating body 50 such as the inclination is prevented.

  In addition, in this example apparatus 100 having the above-described configuration, the holder 70 as described above is used to position and hold each heating body 50 with respect to the base member 10. In this example, as described above, the insertion / fixing means is provided with a screw 53b on the outer peripheral surface of the cylindrical main body 53 forming the heating body 50, and the cylindrical shape is interposed via this screw (male screw). The screw (female screw) 73b provided in the holder 70 is fixed by being screwed from the lower end side of the holder 70 in the figure. The rear end of the cylindrical main body 53 forming the heating body 50 is provided with a large-diameter polygonal portion 58 for screwing, but is smaller in diameter than the cylindrical main body 72 of the holder 70. Yes. For this reason, the heater 50 is fixed to the holder 70 before the heater 50 is attached to the heater mounting through-hole 13 in the base member 10 before the heater plate 30 is attached to the support plate 20 of the intermediate plate 90 and the heater 30. In the state, the holder 70 with the coil spring 80 can be attached from above the base member 10 so as to be inserted into the through hole 13 for attaching the heating element. However, in the mounting state, since the cylindrical main body 53 of the heating body 50 can be screwed down from the holder 70 below the base member 10, the heating body mounting through-hole 13 is provided. The heating body 50 can also be attached to the holder 70 inserted therein by screwing upward from below the base member 10 via the screw 53b on the outer peripheral surface of the cylindrical main body 53. For this reason, for such assembly, it is preferable to provide a space under the base member 10 as in the apparatus 100 of the present example. In this example, the heating body 50 is provided with the holder 70 inserted in the heating body mounting through-hole 13 provided through the base member 10 in the vertical direction. A recess (hole with a bottom) may be used instead of the through hole.

  In addition, although not shown in the example apparatus 100 having the above-described configuration, a control device (controller) including an electric circuit for energizing and heating the resistance heating element and controlling the temperature is provided for each heating element 50. . And by the heat generation of the resistance heating element of each heating element 50 by energization, the temperature of the surface 33 in the heating plate 30 is changed to a required temperature (target temperature) according to the processing content of the substrate K, for example, by feedback control. It is set to allow temperature control (temperature management). In addition, what is necessary is just to perform the temperature detection in such temperature control in appropriate places, such as many site | parts in the plate 30 for a heating.

  Such an apparatus 100 of this example is accommodated and arrange | positioned in a predetermined processing chamber, and is used for the use. And in the use, based on the above-mentioned configuration, by energizing each heating element 50, the heating of the end portions 51 that are provided in a scattered manner on the back surface 34 of the heating plate 30 and enter the respective recesses 37. Thus, the numerous concave portions 37 are heated by heat transfer by contact and radiant heat. In this example apparatus 100, each heating element 50 is not arranged such that the resistance heating element extends long along the surface of the heating plate as in the conventional heating apparatus. That is, in the apparatus 100 of this example, the heating of each heating element 50 is performed in a narrow spot-like range at the end 51. For this reason, in the heat generation by one heating body 50, the heat generation unevenness in the direction extending along the surface of the heating plate 30 does not occur. Then, heat transfer due to the heat generation of the end portion 51 is performed at each of the recessed portions 37 (locations) that are scattered and set on the back surface 34 of the heating plate 30. Therefore, by controlling the heat generation temperatures of the many heating elements 50 without variation, the temperature in the entire predetermined region of the surface 33 of the heating plate 30 can be accurately maintained at the target temperature. Thus, according to the heating apparatus 100 of this example, the structure is not complicated as apparent from the above configuration, and the object to be heated K is brought into contact with the contact surface area of the surface 33 of the heating plate 30. The surface 33 temperature of the object to be heated (substrate) can be kept constant with high accuracy over the entire surface. Therefore, the processing performance of the substrate can be improved.

  Moreover, in this example, since the scattered heating locations are set so as to surround and include the contact surface region T, it is easy to maintain a constant temperature throughout the region corresponding to the contact surface region. In addition, since the heating plate 30 is circular as in the apparatus 100 of this example, the heating body (group) disposed on the outermost periphery is likely to be a low temperature due to heat dissipation at the outer peripheral portion. The temperature is appropriately controlled so that the temperature 50 is selectively higher than that of the heating body (group) 50 disposed on the inner side thereof, and the entire predetermined region of the surface 33 of the plate 30 has a desired temperature. What should I do? However, as a countermeasure for such a tendency to lower the temperature at the outer peripheral portion, as in the heating plate 30 shown in FIG. 6, the heating direction (small circle with hatching) in the circumferential direction of the portion set on the outer peripheral side It is also possible to control the temperature by reducing the distance between the two or by setting the part so as to be unevenly distributed in the part near the outer periphery (contact surface region T).

In this example described above, not only the end portion 51 of each heating body 50 is in contact with the back surface 34 of the heating plate 30 but also the pressure contact that is fitted into the recess 37 and elastically pressed. High heat transfer by reliable contact can be obtained even with displacement based on thermal effects such as thermal expansion. Moreover, since the bottom surface 37b of the concave portion 37 is a conical surface with respect to the convex spherical surface that is the shape of the end portion 51 of the heating body 50, efficient heat transfer can be obtained. Further, in this example, the intermediate plate 90 is provided as described above, and the portion of the heating body 50 near the tip of the cylindrical main body 53 is positioned and held in the positioning hole 93 provided therein. For this reason, even if the heating plate 30 is removed for replacement, it is easy to maintain the arrangement state of the large number of heating bodies 50 as much as the intermediate plate 90 exists. In this case, a displacement or a cruciform is unlikely to occur at a location where the end portion 51 is to be heated.
Therefore, the exchange work becomes easy. Further, as described above, since heat (radiant heat) at the end portion 51 can be blocked by the intermediate plate 90, the electrical wiring and the like for each heating element 50 can be protected.

Furthermore, in this example apparatus 100, since the edge part 51 in each heating body 50 is not only made to contact the recessed part 37 but is fitted, the position is stabilized .

In the above example, the heating plate 30 is embodied as a circular one. However, in the heating apparatus of the present invention, the shape of the heating plate is not limited, and may be appropriately set according to the object to be heated. . Therefore, as in the modification shown FIG 7- A, to B, it can be embodied as a heating plate 130 square. In this case, the portion to be heated by the end portion of the heating body, that is, the arrangement portion of the end portion of the heating body may be the same as the previous example if the heated body is circular. Further, as shown in FIG. 7- A, when the contact surface region T is square, adjacent portions among the portions to be heated (small circles with hatching) are equally spaced from each other. Thus, it is good to provide so that it may be scattered in the whole in a square surface. In such a case as well, as shown in FIG. 7B , the positions located on the outermost periphery may be arranged so as to have a relatively small interval. In any case, it is preferable to set so that the portion exists outside the contact surface region T. That is, in the present invention, the entire contact surface area of the object to be heated is controlled at a constant temperature in a number of locations that are scattered and set on the back surface of the heating plate that should be heated at the ends of a number of heating elements. It should be set so that it is easy to do.

  The heating plate constituting the heating device of the present invention may be selected from appropriate materials that can be used as a flat heater, and the material is not limited, but a metal such as aluminum or aluminum alloy, alumina, aluminum nitride, A ceramic such as silicon nitride is preferred. Further, the heating device of the present invention is not limited to those in the above examples, and can be embodied with appropriate modifications within a range not departing from the gist thereof. And the use is not limited to the heating in semiconductor manufacture or plasma treatment, but can be widely applied to the heating of an object to be heated. Moreover, although the coil spring was illustrated as a means which presses each heating body elastically toward the said back surface in the said example, another spring can also be used. The heating element used in the heating device of the present invention is a heating element in which a resistance heating element that generates heat when energized is provided at the end, and a large number of locations that are scattered and set on the back surface of the heating plate. Of course, it is only necessary that each of the end portions of the heating body can be heated, and therefore, other than the glow plugs exemplified in the above example.

DESCRIPTION OF SYMBOLS 10 Base member 13 Through-hole 20 for attachment of heating body Strut 30 Heating plate 33 Heating plate surface 34 Heating plate back surface 37 Recessed portion (concave portion into which end can be fitted, scattered on heating plate rear surface A lot of places set)
50 Heating body 51 End 90 of heating body Intermediate plate 93 Positioning hole 100 Heating device T Contact surface area K of heated object Heated object

Claims (8)

A heating apparatus comprising a heating plate having a flat surface for contacting and heating an object to be heated, and a heating body for heating the surface,
For the heating element, a number of heating elements provided with end portions of resistance heating elements that generate heat when energized are used,
In many places set to be scattered on the back surface of the heating plate, the end portions of the plurality of heating bodies are provided with concave portions formed by circular holes that are fitted by gap fitting. The heating device, wherein the multiple heating elements are provided on the back side of the heating plate so as to heat the multiple portions by being fitted into the recesses and brought into contact with each other.   A plurality of locations that are scattered and set on the back surface of the heating plate include and surround an area corresponding to the contact surface region of the object to be heated on the front surface of the back surface of the heating plate. The heating device according to claim 1, wherein the heating device is a large number of locations set in a scattered manner. A heating apparatus comprising a heating plate having a flat surface for contacting and heating a circular object to be heated, and a heating body for heating the surface,
For the heating element, a number of heating elements provided with end portions of resistance heating elements that generate heat when energized are used,
Among the back surface of the heating plate, in a number of locations set to be scattered in surrounding regions including and surrounding a region corresponding to a circular contact surface region with the object to be heated on the front surface , A recessed portion into which the end portion of a large number of heating bodies can be fitted is provided, and the end portion is fitted into the recessed portion and is in contact with the back surface . The heating elements are provided on the back side of the heating plate so as to be heated, and the contact surface area is scattered on the front surface and the surrounding area is scattered on the surrounding area. A circumferential groove that is concentric with the contact surface region is cut into both the front and back surfaces of the heating plate so as to surround all of the numerous portions set in this manner. The heating apparatus according to any one of claims 1 to 3, wherein the contact of the end portion is a pressure contact that elastically presses each heating body toward the back surface. The space between the adjacent locations located at the outermost side of the location group among the multiple locations is smaller than the interval between the adjacent locations at other positions. The heating apparatus according to any one of 1 to 4 . The heating body is a rod-shaped body, and the resistance heating element is provided at the end of the rod-shaped body, and the heating body is substantially perpendicular to the back surface of the heating plate. The heating device according to any one of claims 1 to 5 , wherein the heating device is provided. The heating device includes a base member and a support column erected on the base member, the heating plate is detachably attached to the upper end side of the support column, and the multiple heating elements are The heating apparatus according to claim 6 , wherein the heating apparatus is positioned and held by a recessed portion or a through-hole provided individually in the base member, and is provided with the end portion facing up. The heating apparatus according to claim 7 , wherein an intermediate plate is provided between the base member and the heating plate so as to be substantially parallel to the heating plate, A heating device, wherein the heating plate is provided in a state of passing through positioning holes individually provided in the intermediate plate and positioning the upper and lower intermediate portions of each heating body in the positioning holes.

Images