JP3555734B2 - Substrate heat treatment equipment - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention applies a polyimide resin solution or a photoresist solution to various substrates such as a semiconductor substrate, a glass substrate for a liquid crystal display device, a glass substrate for a photomask, and a substrate for an optical disk, and then heats the substrate to form a solvent. The present invention relates to a substrate heating apparatus for evaporating components.
[0002]
[Prior art]
A conventional substrate heating apparatus of this type will be described with reference to FIG.
The substrate heating apparatus includes a heating plate 1 on which a substrate W such as a semiconductor substrate is placed, and a cover 2 that can move up and down to cover the substrate W on the heating plate 1. With the cover 2 open, a substrate W coated with a polyimide resin or the like is placed on the heating plate 1, and then the cover 2 is lowered to form a processing space S in the cover 2. When the substrate W is heated by the heating plate 1, the solvent component evaporates from the substrate W. Specifically, when the polyimide resin liquid is applied to the substrate W, NMP (N-methyl-2-pyrrolidone), which is a solvent for the polyimide resin, evaporates. This solvent component is forcibly exhausted through an exhaust pipe 4 connected to the upper part of the cover 2. A ring-shaped member 5 made of a fluororesin or the like is fitted to the lower end of the cover 2 to prevent the metal cover 2 from generating particles due to direct contact with the heating plate 1. .
[0003]
However, according to this substrate heating apparatus, since the cover 2 is thermally separated from the heating plate 1 by the resin member 5, the temperature of the cover 2 is relatively low and the solvent component evaporated from the substrate W It is cooled by contacting the inner wall of the cover 2. As a result, the solvent component is condensed on the inner wall of the cover 2, and the condensed solvent component may fall on the substrate W and contaminate the substrate W.
[0004]
In view of this, the present applicant has previously proposed a substrate heating apparatus that prevents the solvent component from condensing and adhering to the inner wall of the cover 2 (see Japanese Utility Model Laid-Open No. 6-45335). Hereinafter, description will be made with reference to FIG. The substrate heating apparatus includes a cover 9 including a short cylindrical first cover member 6 and a second cover member 8 attached to the first cover member 6 via a screw member 7. I have. An annular flow path 10 is formed between the first cover member 6 and the second cover member 8. At the time of heat treatment of the substrate W, outside air is taken into the cover 9 from the annular flow path 10, and the outside air is forcibly exhausted along the inner wall of the cover 9. According to such an exhaust structure, the solvent component evaporated from the substrate W is exhausted together with the outside air taken into the cover 9 without coming into contact with the inner wall of the cover 9. Can be prevented.
[0005]
[Problems to be solved by the invention]
As described above, the substrate heating apparatus disclosed in Japanese Utility Model Laid-Open No. 6-45335 can effectively prevent the evaporated solvent component from condensing on the inner wall of the cover 9. It is required that the exhaust means (not shown) has sufficient exhaust capacity. However, in some cases, it is difficult to secure the exhaust capability of the exhaust unit. This will be specifically described below.
[0006]
With recent miniaturization of semiconductor devices, a polyimide resin film used as a protective film tends to be thick. When the polyimide resin is applied thickly on the substrate, the amount of evaporation of the solvent component in the cover of the substrate heat treatment apparatus increases. Therefore, it is necessary to increase the exhaust amount in the cover in order to prevent dew condensation of the solvent component. However, the exhaust line provided in a semiconductor manufacturing plant in which this type of substrate heating apparatus is installed is commonly used in other apparatuses using an organic solvent, and therefore, it is necessary to increase the exhaust capacity. There are times when you can't. In such a case, even with the substrate heating apparatus disclosed in Japanese Utility Model Laid-Open No. 6-45335, the dew condensation of the solvent component cannot be effectively prevented.
[0007]
The present invention has been made in view of such circumstances, and a substrate heat treatment apparatus capable of effectively preventing dew condensation of a solvent component on an inner wall of a cover without increasing the exhaust amount in the cover. It is intended to provide.
[0008]
[Means for Solving the Problems]
The present invention has the following configuration to achieve such an object.
That is, the invention according to claim 1 is a heating plate on which a substrate to be subjected to a heat treatment is placed, and has a shape in which the lower end is open and the upper part is closed, and covers the substrate placed on the heating plate. While forming a processing space therein, a cover having an exhaust hole communicating with the processing space, and a cover that supports the cover by contacting a metal exposed surface at a lower end of the cover during heat treatment of the substrate; A cover receiving portion that is thermally coupled to the heating plate, and a partition portion that separates the substrate receiving surface of the heating plate from the cover receiving portion.
[0009]
According to a second aspect of the present invention, in the substrate heating apparatus according to the first aspect, the partition wall is a metal tubular body attached to the heating plate so as to surround the substrate mounting surface of the heating plate. The cover receiving portion is a metal flange attached to the outer peripheral surface of the tubular body.
[0010]
According to a third aspect of the present invention, in the substrate heating apparatus according to the first aspect, the partition is a tubular body attached to the heating plate so as to surround a substrate mounting surface of the heating plate, The cover receiving portion is an upper surface portion of the heating plate located outside the tubular body.
[0011]
According to a fourth aspect of the present invention, in the substrate heating apparatus according to the first aspect, the heating plate is formed so as to surround the substrate mounting surface, and the step portion is lower than the substrate mounting surface. And the cover receiving portion is a flat surface of the step portion, and the partition portion is a rising wall surface of the step portion.
[0012]
According to a fifth aspect of the present invention, in the substrate heating apparatus of the second aspect, the outside air is introduced into the processing space at a position lower than a position where the flange is attached to the cylindrical body. Holes are formed.
[0013]
According to a sixth aspect of the present invention, in the substrate heating apparatus according to the third or fourth aspect, the cover is provided with a hole for introducing outside air into the processing space.
[0014]
[Action]
The operation of the invention described in claim 1 is as follows.
During the heat treatment of the substrate, the exposed metal surface at the lower end of the cover comes into contact with the cover receiving portion thermally coupled to the heating plate. As a result, heat is conducted from the heating plate to the cover, and the temperature of the cover increases. Therefore, even if the solvent component evaporates from the substrate placed on the heating plate, the solvent component is not cooled by the inner wall of the cover, so that the solvent component does not condense on the cover and is discharged through the exhaust hole of the cover. Also, even if particles are generated due to contact of the metal exposed surface at the lower end of the cover with the cover receiving portion, since the substrate mounting surface of the heating plate and the cover receiving portion are separated by the partition, the particles Does not enter the substrate mounting surface of the heating plate and contaminate the substrate.
[0015]
According to the invention described in claim 2, the heat of the heating plate is transmitted to the cover via the tubular body and the flange, and the temperature of the cover rises, so that the solvent component evaporated from the substrate is applied to the inner wall of the cover. No condensation. Also, even if the metal exposed surface of the lower end of the cover comes into contact with the flange portion and particles are generated, the particles are not covered by the substrate of the heating plate because the substrate mounting surface of the heating plate is surrounded by the cylindrical body. There is no intrusion into the mounting surface to contaminate the substrate.
[0016]
According to the third aspect of the invention, since the heat of the heating plate is directly transmitted to the cover and the temperature of the cover rises, the solvent component evaporated from the substrate does not condense on the inner wall of the cover. Also, even if the exposed metal surface at the lower end of the cover comes into contact with the upper surface of the heating plate and particles are generated, the particles are heated because the substrate mounting surface of the heating plate is surrounded by a cylindrical body. There is no contamination of the substrate by invading the substrate mounting surface side of the plate.
[0017]
According to the fourth aspect of the present invention, the temperature of the cover rises when the lower end of the cover comes into contact with the flat surface of the step portion of the heating plate, so that the solvent component evaporated from the substrate condenses on the inner wall of the cover. Nothing. Also, even if the exposed metal surface at the lower end of the cover and the flat surface of the step portion of the heating plate come into contact with each other and particles are generated, if the substrate mounting surface of the heating plate and the flat surface of the step portion of the heating plate are Also, since the particles are separated by the rising wall surface of the step, the particles do not enter the substrate mounting surface side of the heating plate and contaminate the substrate.
[0018]
According to the fifth aspect of the invention, the solvent component evaporated from the substrate is discharged from the exhaust hole of the cover on the airflow of the outside air taken into the processing space from the hole formed in the cylindrical body.
[0019]
According to the sixth aspect of the present invention, the solvent component evaporated from the substrate is exhausted from the exhaust hole of the cover on the airflow of the outside air introduced into the processing space from the hole formed in the cover.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First embodiment>
FIG. 1 is a sectional view showing a schematic configuration of a first embodiment of a substrate heating apparatus according to the present invention.
[0021]
The substrate heating apparatus includes a heating plate 10 on which a substrate W to be heated is placed. The substrate W to be heated is, for example, a semiconductor wafer coated with a polyimide resin solution. The central region of the upper surface of the heating plate 10 is a substrate mounting surface 10a. On the upper surface of the heating plate 10, a short cylindrical body 20 is screwed and fixed so as to surround the substrate mounting surface 10a, and is thermally coupled to the heating plate 10. The tubular body 20 is formed of a metal such as stainless steel. In addition, the attachment method for thermally coupling the cylindrical body 20 to the heating plate 10 is not limited to screw fixing, an annular groove is formed in the heating plate 10, and the cylindrical body 20 is press-fitted into this groove. Alternatively, the tubular body 20 may be connected to the heating plate 10 by welding.
[0022]
A flange portion 21 is attached to the outer peripheral surface of the cylindrical body 20 at a height approximately in the middle. This flange portion 21 is also formed of a metal such as stainless steel, similarly to the tubular body 20. A hole 22 for taking in outside air is formed in the tubular body 20 at a position lower than the position where the flange 21 is attached. As will be apparent from the following description, the tubular body 20 corresponds to a partition in the present invention, and the flange 21 corresponds to a cover receiver.
[0023]
Further, the substrate heating apparatus includes a bell-shaped cover 30 having an open lower end and a closed upper end. The cover 30 is formed of a metal such as stainless steel. During the heat treatment of the substrate W, the metal exposed surface 30a at the lower end of the cover 30 comes into contact with the flange portion 21, and a processing space S is formed inside the cover 30. An exhaust hole 31 is formed at the upper end of the cover 30, and an exhaust pipe 32 is connected to the exhaust hole 31. The exhaust pipe 32 is connected to an exhaust unit (not shown).
[0024]
The heating plate 10 is provided with a plurality of vertically movable substrate support pins 40 that protrude and retract from the substrate mounting surface 10a. This substrate support pin 40 is connected to a rod of an air cylinder 42 via a mounting arm 41. The cover 30 is also connected to the rod of the air cylinder 42 via the support arm 43. When the rod of the air cylinder 42 expands and contracts, the substrate support pins 40 and the cover 30 move up and down in synchronization with this.
[0025]
Next, the operation of the first embodiment having the above-described configuration will be described.
When the rod of the air cylinder 42 is extended to carry in the substrate W, as shown in FIG. 2, the cover 30 is raised, and the substrate support pins 40 protrude from the substrate mounting surface 10a. A substrate transport robot (not shown) transports the substrate W and transfers the substrate W onto the substrate support pins 40. Subsequently, the rod of the air cylinder 42 contracts, and the substrate support pins 40 move down, so that the substrate W is placed on the substrate placing surface 10a. Simultaneously with the lowering of the substrate support pins 40, the cover 30 is lowered, and the metal exposed surface 30a at the lower end of the cover 30 contacts the flange 21 of the tubular body 20, thereby supporting the cover 30 (the state shown in FIG. 1). ).
[0026]
The substrate W placed on the substrate platform 10a is heated by the heating plate 10. When the substrate W is coated with, for example, a polyimid resin, the solvent component (N-methyl-2-pyrrolidone) evaporates. The solvent component released into the processing space S is discharged through the exhaust hole 31 together with the outside air taken into the processing space S from the hole 22 of the cylindrical body 20. At this time, since the tubular body 20 is thermally coupled to the heating plate 10, the flange 21 of the tubular body 20 is at substantially the same temperature as the heating plate 10. Since the flange portion 21 is in contact with the metal exposed surface 30a at the lower end of the cover 30, the temperature of the cover 30 is also high. Therefore, even if the solvent component evaporated from the substrate W comes into contact with the inner wall of the cover 30, the solvent is not cooled, and the solvent component is not condensed on the inner wall of the cover 30 and is smoothly exhausted. Incidentally, when the temperature of the cover 30 is 60 to 70 ° C. or higher, the solvent component does not condense on the inner wall of the cover 30. In addition, even if particles are generated due to the metal exposed surface 30a at the lower end of the cover 30 being in direct contact with the flange 21, the cylindrical body 20 is interposed between the substrate mounting surface 10a and the flange 21. Since the two are separated from each other, the particles do not enter the substrate mounting surface 10a side and contaminate the substrate W.
[0027]
When the heat treatment of the substrate W is completed, the rod of the air cylinder 42 is extended, the substrate support pins 40 are raised, the substrate W is lifted, and the cover 30 is raised. Subsequently, after a substrate transfer robot (not shown) unloads the processed substrate W, a new substrate W is loaded. Thereafter, the same heat treatment is repeatedly performed.
[0028]
<Second embodiment>
FIG. 3 is a sectional view showing a schematic configuration of a second embodiment of the substrate heating apparatus according to the present invention. In FIG. 3, the components indicated by the same reference numerals as those in FIG. 1 are the same as those in the first embodiment, and thus description thereof will be omitted.
[0029]
The features of the substrate heating apparatus according to the second embodiment are as follows.
A cylindrical body 23 as a partition is provided on the heating plate 10 so as to surround the substrate mounting surface 10a of the heating plate 10. The upper surface portion 10b of the heating plate 10 located outside the cylindrical body 23 is used as a cover receiving portion that supports the cover 33 by contacting the metal exposed surface 30a at the lower end of the cover 33. The cover 33 is provided with a hole 34 for taking in outside air into the processing space S.
[0030]
According to the present embodiment, the metal exposed surface 30a at the lower end of the cover 33 is in direct contact with the upper surface portion 10b of the heating plate 10, so that the temperature of the cover 33 is more effectively increased. Therefore, even if the solvent component evaporates from the substrate W due to the heat treatment, no dew condensation occurs on the inner wall of the cover 33. The evaporated solvent component is discharged from the exhaust hole 31 together with the outside air taken in from the hole 34 of the cover 33. Since the substrate mounting surface 10a is surrounded by the cylindrical body 23, even if the metal exposed surface 30a at the lower end of the cover 33 comes into contact with the upper surface portion 10b of the heating plate 10 and particles are generated, the substrate mounting surface There is no intrusion into the 10a side to contaminate the substrate W.
[0031]
<Third embodiment>
FIG. 4 is a sectional view showing a schematic configuration of a third embodiment of the substrate heating apparatus according to the present invention. In FIG. 4, the components indicated by the same reference numerals as those in FIG. 1 are the same as those in the first embodiment, and the description thereof will be omitted.
[0032]
The features of the substrate heating apparatus according to the third embodiment are as follows.
The heating plate 10 has a ring-shaped step portion 11 which is lower than the substrate mounting surface 10a so as to surround the substrate mounting surface 10a. The flat surface 11a of the step portion 11 forms a cover receiving portion that supports the cover 35 by contacting the metal exposed surface 30a at the lower end of the cover 35. In addition, the rising wall surface 11b of the step portion 11 has a function as a partition portion that separates the substrate mounting surface 10a from the cover receiving portion. The cover 35 is provided with a hole 36 for taking outside air into the processing space S.
[0033]
According to the present embodiment, since the metal exposed surface 30a at the lower end of the cover 35 is in contact with the flat surface 11a of the step portion 11 of the heating plate 10, the temperature of the cover 35 rises. Therefore, even if the solvent component evaporates from the substrate W due to the heat treatment, no dew condensation occurs on the inner wall of the cover 35. The evaporated solvent component is discharged from the exhaust hole 31 together with the outside air taken in from the hole 36 of the cover 35. Since the substrate mounting surface 10a is surrounded by the rising wall surface 11b of the step portion 11, the metal exposed surface 30a at the lower end of the cover 35 comes into contact with the flat surface 11a of the step portion 11 of the heating plate 10 to temporarily generate particles. However, the substrate W is not contaminated by entering the substrate mounting surface 10a.
[0034]
In each of the above-described embodiments, if the cover 30, 33, 35 or the exhaust pipe 32 is heated by attaching a sheet heater or the like to the outer peripheral surface of the cover 30, 33, 35 or the exhaust pipe 32, the substrate can be heated. The effect of preventing dew condensation of the solvent component evaporated from W can be further enhanced.
[0035]
【The invention's effect】
As apparent from the above description, the present invention has the following effects.
According to the first aspect of the present invention, the temperature of the cover increases during the heat treatment of the substrate, so that the solvent component evaporated from the substrate does not condense on the inner wall of the cover. Therefore, it is not necessary to increase the exhaust volume in the cover in order to prevent the dew condensation of the solvent component in the cover. Further, since the substrate mounting surface of the heating plate and the cover receiving portion are separated by the partition wall portion, even if the lower end of the cover and the cover receiving portion come into contact with each other and generate particles, the particles may be placed on the heating plate. There is no contamination of the substrate.
[0036]
Similarly, according to the second to fourth aspects of the present invention, the temperature of the cover rises during the heat treatment of the substrate, so that the solvent component does not condense on the inner wall of the cover. Further, according to the second and third aspects of the present invention, the substrate mounting surface of the heating plate is surrounded by a cylindrical body. Since the substrate mounting surface is surrounded by the rising wall surface of the step, there is no possibility that particles enter the substrate mounting surface of the heating plate from the outside and contaminate the substrate.
[0037]
Furthermore, according to the fifth aspect of the present invention, the treatment is performed via a hole formed in the cylindrical body, and according to the sixth aspect of the invention, the treatment is performed via the hole formed in the cover. Since the outside air is taken into the space, the solvent component evaporated from the substrate can be put on the airflow of the outside air and smoothly discharged from the exhaust hole of the cover.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a schematic configuration of a first embodiment of a substrate heating apparatus according to the present invention.
FIG. 2 is a cross-sectional view showing a state when the substrate is carried in and out of the apparatus of the first embodiment.
FIG. 3 is a sectional view showing a schematic configuration of a second embodiment.
FIG. 4 is a sectional view showing a schematic configuration of a third embodiment.
FIG. 5 is a sectional view showing a schematic configuration of a conventional device.
FIG. 6 is a cross-sectional view showing a schematic configuration of a conventional device.
[Explanation of symbols]
10: heating plate 10a: substrate mounting surface 10b: upper surface portion (cover receiving portion)
11: step portion 11a: flat surface of the step portion (cover receiving portion)
11b: The rising wall surface of the step (partition)
20, 23 ... cylindrical state (partition wall)
21: Flange (cover receiving part)
22 ... holes for taking in outside air 30, 33, 35 ... cover 30a ... exposed metal surface 31 ... exhaust holes 34, 36 ... holes for taking in outside air W ... substrate S ... processing space

Claims (6)

A heating plate on which a substrate to be heated is placed;
A lower end is open, has a closed upper shape, covers a substrate placed on the heating plate, forms a processing space therein, and has a cover provided with an exhaust hole communicating with the processing space,
A cover receiving portion that is in contact with the metal exposed surface at the lower end of the cover during the heat treatment of the substrate to support the cover, and that is thermally coupled to the heating plate;
A substrate heat treatment apparatus, comprising: a partition portion that separates a substrate mounting surface of the heating plate from the cover receiving portion. The substrate heating apparatus according to claim 1,
The partition portion is a metal tubular body attached to the heating plate so as to surround the substrate mounting surface of the heating plate,
The substrate heating apparatus, wherein the cover receiving portion is a metal flange attached to an outer peripheral surface of the tubular body. The substrate heating apparatus according to claim 1,
The partition is a tubular body attached to the heating plate so as to surround the substrate mounting surface of the heating plate,
The substrate heating apparatus, wherein the cover receiving portion is an upper surface portion of the heating plate located outside the tubular body. The substrate heating apparatus according to claim 1,
The heating plate is formed to surround the substrate mounting surface, and includes a step portion that is lower than the substrate mounting surface,
The cover receiving portion is a flat surface of the step portion,
The substrate heating apparatus, wherein the partition wall portion is a rising wall surface of the step portion. The substrate heating apparatus according to claim 2,
A substrate heating processing apparatus, wherein a hole for taking in outside air into the processing space is formed in the cylindrical body at a position lower than a position where the flange is attached. The substrate heating apparatus according to claim 3 or 4,
A substrate heating apparatus, wherein the cover has a hole for introducing outside air into the processing space.

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