JP7761983B2 - Heat Treatment Equipment - Google Patents

Description

An embodiment of the present invention relates to a heat treatment device.

2. Description of the Related Art There are heat treatment devices that heat a workpiece to form a film or the like on the surface of the workpiece or to treat the surface of the workpiece.
For example, a heat treatment device has been proposed that includes a chamber in which a workpiece is held and multiple heaters provided inside the chamber. The multiple heaters are rod-shaped and extend in one direction above and below the workpiece. If multiple heaters are provided above and below the workpiece, the workpiece can be heated from above and below. Therefore, the workpiece can be heated efficiently.

However, heat from a workpiece easily escapes from the periphery to the outside, but is difficult to escape from the center of the workpiece. Therefore, simply heating the workpiece from above and below will result in a lower temperature in the peripheral region of the workpiece than in the central region of the workpiece. If the temperature difference between the peripheral region of the workpiece and the central region of the workpiece becomes too large, there is a risk that the quality of the film or treatment layer formed on the surface of the workpiece will deteriorate.

Therefore, there was a need to develop a heat treatment device that could reduce temperature variations within the surface of the workpiece.

JP 2019-184229 A

The problem that this invention aims to solve is to provide a heat treatment device that can reduce temperature variations within the surface of a workpiece.

A heat treatment apparatus according to an embodiment includes a chamber having a heating region therein for heat-treating a workpiece, a first heater provided inside the chamber at least above or below the heating region and extending in a first direction, and a second heater provided inside the chamber alongside the first heater in a second direction intersecting the first direction and extending in the first direction , the first heater being configured as a single heater or a pair of heaters and being arranged to heat a central region and a peripheral region of the heating region in the first direction, The second heater is composed of a pair of sets, and the pair of sets are arranged opposite each other so as to heat the peripheral region of the heating region in the first direction, the first heaters are arranged in a row in the second direction, the second heaters are arranged in a row in the second direction, at least one second heater is arranged between the first heater and the first heater in the second direction, and the lengths of both of the pair of second heaters are shorter than half the length in the first direction of the heating region heated by the first heater.

Embodiments of the present invention provide a heat treatment device that can reduce temperature variations within the surface of a workpiece.

1 is a schematic front view illustrating a heat treatment apparatus according to an embodiment of the present invention; 2 is a schematic cross-sectional view of the heat treatment device in FIG. 1 taken along line AA. FIG. 2 is a schematic perspective view of a chamber and a cassette rack. FIG. 2 is a schematic perspective view illustrating a support portion. 10A and 10B are schematic diagrams for illustrating the function of the support portion. FIG. 2 is a schematic perspective view illustrating a holding portion. FIG. 10 is a schematic diagram illustrating the arrangement of heaters in the Z direction. FIG. 10 is a schematic diagram illustrating the tip position of a heater. 10A and 10B are schematic views for illustrating support of a heater by a support portion. 10A and 10B are schematic views for illustrating support of a heater by a support portion. FIG. 2 is a schematic perspective view illustrating a cassette. 10A and 10B are schematic cross-sectional views illustrating a heater according to another embodiment. 10A to 10C are schematic views illustrating support of a heater by a support portion according to another embodiment.

Embodiments will be illustrated below with reference to the drawings. Note that in each drawing, similar components are given the same reference numerals and detailed descriptions will be omitted where appropriate. In addition, the X direction (equivalent to an example of the first direction), Y direction (equivalent to an example of the second direction), and Z direction in each drawing represent three mutually orthogonal directions. For example, the X direction and Y direction are horizontal directions. For example, the Z direction is the up-down direction (vertical direction).

The following describes, as an example, a heat treatment device that heats a workpiece in an atmosphere that is reduced in pressure below atmospheric pressure to form an organic film on the surface of the workpiece. However, the present invention is not limited to this. For example, the present invention can also be applied to heat treatment devices that heat a workpiece to form an inorganic film or the like on the surface of the workpiece, or that process the surface of the workpiece.

Furthermore, the workpiece before heating may, for example, include a substrate and a solution applied to the surface of the substrate, or may be just a substrate. Below, as an example, we will explain a case where the workpiece before heating includes a substrate and a solution applied to the surface of the substrate.

Before being heat-treated by the heat treatment apparatus 1 according to this embodiment, the workpiece 100 has a substrate and a solution applied to the surface of the substrate. The substrate is, for example, a glass substrate or a semiconductor wafer. However, the substrate is not limited to the examples given. The solution contains, for example, an organic material and a solvent. There are no particular restrictions on the organic material as long as it can be dissolved by the solvent. The solution can be, for example, a varnish containing polyamic acid. However, the solution is not limited to the examples given. The solution may also be a liquid that has been pre-baked to a semi-hardened state (a state in which it does not flow).

FIG. 1 is a schematic front view illustrating a heat treatment apparatus 1 according to the present embodiment.
In FIG. 1, only one cassette 50 is shown to avoid complication.
FIG. 2 is a schematic cross-sectional view of the heat treatment apparatus 1 taken along line AA in FIG.
In FIG. 2, the cassette 50 is omitted to avoid complication.
FIG. 3 is a schematic perspective view of the chamber 10 and the cassette rack 60. As shown in FIG.

As shown in Figures 1 and 2, the heat treatment apparatus 1 is provided with, for example, a chamber 10, an exhaust unit 20, a heating unit 30, a cooling unit 40, a cassette 50, a cassette rack 60, and a controller 70.

The controller 70 includes, for example, a calculation unit such as a CPU (Central Processing Unit) and a storage unit such as a memory. The controller 70 is, for example, a computer. The controller 70 controls the operation of each element provided in the heat treatment device 1 based on, for example, a control program stored in the storage unit.

As shown in Figures 1 to 3, the chamber 10 is box-shaped. The chamber 10 has an airtight structure that can maintain an atmosphere at a reduced pressure below atmospheric pressure. There are no particular limitations on the external shape of the chamber 10. The external shape of the chamber 10 can be, for example, a rectangular parallelepiped or a cylinder. The chamber 10 is formed from a metal such as stainless steel.

For example, openings are provided at both ends of the chamber 10 in the Y direction. A flange 11 is provided at one end of the chamber 10 in the Y direction. A sealant 12 such as an O-ring is provided on the flange 11. An opening/closing door 13 is provided on the side of the chamber 10 where the flange 11 is provided. When the opening/closing door 13 is closed, the opening of the chamber 10 is closed airtight by the sealant 12. When the opening/closing door 13 is opened, the workpiece 100 can be loaded into or loaded out of the cassette 50 through the opening of the chamber 10.
That is, the chamber 10 has a heating region therein for heat-treating the workpiece 100. The cassette 50 provided inside the chamber 10 defines the heating region for heating the workpiece 100. The cassette 50 stores the workpiece 100 therein.

A flange 14 is provided at the other end of the chamber 10 in the Y direction. A sealant 12 is provided on the flange 14. A lid 15 is provided on the side of the chamber 10 where the flange 14 is provided. For example, the lid 15 is detachably attached to the flange 14 using a fastening member such as a screw. When the lid 15 is attached, the opening of the chamber 10 is closed airtight by the sealant 12. The provision of a removable lid 15 facilitates maintenance of the heat treatment device 1 from the side where the flange 14 is provided. Furthermore, when the lid 15 is opened for maintenance, the cassette 50 can be carried into the chamber 10 through the opening. Alternatively, the cassette 50 can be carried out of the chamber 10 through the opening.

A cooling device (not shown) can be provided on the outer wall of the chamber 10. The cooling device can be, for example, a water jacket. If a cooling device is provided, the temperature of the outer wall of the chamber 10 can be prevented from rising above a predetermined temperature.

The exhaust unit 20 exhausts the inside of the chamber 10 .
1, the exhaust unit 20 includes a first exhaust unit 21 and a second exhaust unit 22. The first exhaust unit 21 and the second exhaust unit 22 are connected to an exhaust port 16 provided on the bottom surface of the chamber 10.

The first exhaust unit 21 includes an exhaust pump 21a and a pressure control unit 21b.
The exhaust pump 21a may be an exhaust pump that performs rough exhaust from atmospheric pressure to a predetermined pressure. Therefore, the exhaust pump 21a has a larger exhaust volume than the exhaust pump 22a described below. The exhaust pump 21a may be, for example, a dry vacuum pump.

The pressure control unit 21b is located between the exhaust port 16 and the exhaust pump 21a. The pressure control unit 21b controls the internal pressure of the chamber 10 to a predetermined pressure based on the output of a vacuum gauge (not shown) that detects the internal pressure of the chamber 10. The pressure control unit 21b can be, for example, an APC (Auto Pressure Controller).

The second exhaust unit 22 includes an exhaust pump 22a and a pressure control unit 22b.
The exhaust pump 22a exhausts the air to a lower predetermined pressure after the rough exhaust by the exhaust pump 21a. The exhaust pump 22a has an exhaust capacity capable of exhausting the air to a molecular flow region of a high vacuum. For example, the exhaust pump 22a may be a turbo molecular pump (TMP).

The pressure control unit 22b is located between the exhaust port 16 and the exhaust pump 22a. The pressure control unit 22b controls the internal pressure of the chamber 10 to a predetermined pressure based on the output of a vacuum gauge (not shown) that detects the internal pressure of the chamber 10. The pressure control unit 22b can be, for example, an APC.

Reducing the pressure in the internal space of chamber 10 reduces the amount of heat released outside chamber 10. This improves heating efficiency and heat storage efficiency, allowing for a reduction in the power applied to heater 33 (an example of a first heater) and heater 36 (an example of a second heater), which will be described later. Reducing the power applied to heaters 33 and 36 prevents the load on heaters 33 and 36 from becoming too high. This allows for a longer lifespan for heaters 33 and 36.

The heating unit 30 includes, for example, a first heating unit 31 and a second heating unit 32. The first heating unit 31 and the second heating unit 32 are provided inside the chamber 10.
The first heating unit 31 is provided above the cassette 50 .
The second heating unit 32 is provided below the cassette 50. The second heating unit 32 faces the first heating unit 31.

As mentioned above, the workpiece 100 is stored inside the cassette 50. Therefore, the first heating unit 31 heats the front surface (top surface) of the workpiece 100 stored inside the cassette 50. The second heating unit 32 heats the back surface (bottom surface) of the workpiece 100 stored inside the cassette 50.

As shown in FIG. 1, when multiple cassettes 50 are arranged side by side in the Z direction (vertical direction) inside the chamber 10, the second heating unit 32 provided below the upper cassette 50 can serve as the first heating unit 31 provided above the lower cassette 50. In other words, the first heating unit 31 and the second heating unit 32 provided between the cassettes 50 can be used interchangeably.

For convenience, when focusing on one cassette 50, the upper side as viewed from the cassette 50 is designated as the first heating section 31 and the lower side as the second heating section 32, but heating sections 30 can be provided on the top and bottom of all cassettes 50.

In this case, the back surface of the workpiece 100 stored inside the upper cassette 50 is heated by the shared first heating unit 31 or second heating unit 32. The front surface of the workpiece 100 stored inside the lower cassette 50 is heated by the shared first heating unit 31 or second heating unit 32.
In this way, it is possible to reduce the number of first heating sections 31 or second heating sections 32. As a result, it is possible to reduce power consumption, manufacturing costs, and space.

Each of the first heating unit 31 and the second heating unit 32 includes, for example, a heater 33, a support unit 34, a holding unit 35, a heater 36, and a support unit 37.

At least one heater 33 is provided. When multiple heaters 33 are provided, as shown in FIGS. 1 and 2 , the heaters 33 may extend in the X direction and be aligned in the Y direction. The heaters 33 may also extend in the Y direction and be aligned in the X direction. That is, the heaters 33 are aligned in a direction intersecting the central axes of the heaters 33. However, an openable/closable door 13 and a lid 15 are provided at the Y-direction end of the chamber 10. Therefore, it is preferable that the heaters 33 extend in the X direction and be aligned in the Y direction. This facilitates opening and closing the door 13 and the lid 15, and facilitating the installation and removal of the heaters 33.

The heaters 33 may be arranged at equal intervals, or the intervals may be varied depending on the temperature variations within the surface of the workpiece 100. For example, heat from the workpiece 100 is more likely to escape to the outside from the edges of the workpiece 100 and less likely to escape to the outside from the center of the workpiece 100. Therefore, the intervals between heaters 33 provided on the edges of the workpiece 100 can be narrower than the intervals between heaters 33 provided on the center of the workpiece 100.

Furthermore, the specifications, number, spacing, etc. of the heaters 33 provided in the second heating unit 32 may be the same as or different from the specifications, number, spacing, etc. of the heaters 33 provided in the first heating unit 31. The specifications, number, spacing, etc. of the heaters 33 can be changed as appropriate depending on the composition of the solution to be heated (heating temperature of the solution), the dimensions (planar dimensions) of the workpiece 100 when viewed from the Z direction, etc. The specifications, number, spacing, etc. of the heaters 33 can be determined as appropriate by conducting simulations, experiments, etc.

The heater 33 is rod-shaped and extends in one direction. There are no particular limitations on the heater 33 as long as it is rod-shaped. The heater 33 may be, for example, a sheath heater, a ceramic heater, or a cartridge heater. The heater 33 may have, for example, a quartz cover.
In this specification, the term "rod-shaped heater" includes heaters covered with a quartz cover. There are no limitations on the external shape of the "rod-shaped heater," and it can be, for example, a cylindrical or prismatic shape.

Furthermore, the heater 33 is not limited to the above-mentioned type, as long as it can heat the workpiece 100 in an atmosphere that is reduced in pressure below atmospheric pressure. In other words, the heater 33 may be any type that extends in one direction and is capable of releasing thermal energy by radiation.

As shown in Figures 1 and 2, the support portion 34 is provided inside the chamber 10. The support portion 34 supports the vicinity of one end of the heater 33 inside the chamber 10. For example, one support portion 34 can be provided for one heater 33, or one support portion 34 can be provided for multiple heaters 33.

FIG. 4 is a schematic perspective view illustrating the support portion 34. As shown in FIG.
As shown in FIG. 4, the support portion 34 has a guide portion 34a and a rotating portion 34b.
The guide portion 34a is provided below the heater 33. The guide portion 34a has, for example, a mounting plate 34a1, a plate 34a2, and a guide plate 34a3. The mounting plate 34a1, the plate 34a2, and the guide plate 34a3 can be integrally formed by, for example, bending a plate material.

The mounting plate 34 a 1 is provided on, for example, a frame 61 of a cassette rack 60 .
The plate 34a2 is provided between the mounting plate 34a1 and the guide plate 34a3 in the X direction. One end of the plate 34a2 in the X direction is connected to the upper end of the mounting plate 34a1 in the Z direction. The other end of the plate 34a2 in the X direction is connected to the lower end of the guide plate 34a3 in the Z direction. The plate 34a2 is also provided below the heater 33 with a predetermined distance between them. For example, the plate 34a2 can have a horizontal surface facing the heater 33 and extend in the Y direction .

The guide plate 34a3 is located at a different position from the mounting plate 34a1 in the X and Z directions. For example, the guide plate 34a3 is located above the mounting plate 34a1. The guide plate 34a3 is located at the same position as the mounting plate 34a1 in the Y direction. The guide plate 34a3 is located parallel to the mounting plate 34a1.

The guide plate 34a3 has a notch 34a3a that penetrates the thickness direction and into which the heater 33 can be inserted. The notch 34a3a opens at the upper end of the guide plate 34a3 in the Z direction. The notch 34a3a can be a U-shaped notch.

As shown in Figure 4, when the heater 33 is inserted into the notch 34a3a, a gap is provided between the inner wall of the notch 34a3a and the heater 33. The guide portion 34a (guide plate 34a3) prevents the heater 33 from shifting in position in the Y direction, but does not support the heater 33.

The rotating portion 34b is, for example, columnar (solid) or cylindrical (hollow) and extends in a direction intersecting the central axis of the heater 33. The rotating portion 34b is provided between the heater 33 and the plate 34a2 of the guide portion 34a. The rotating portion 34b contacts the heater 33 and the plate 34a2. When the rotating portion 34b is in contact with the heater 33, the heater 33 does not contact the lower inner wall of the notch 34a3a in the Z direction. There may be cases where the heater 33 comes into contact with one side wall of the notch 34a3a in the Y direction. However, the heater 33 is not pressed against the side wall of the notch 34a3a due to gravity.

Since the rotating part 34b comes into contact with the heater 33, it is made of a heat-resistant material. Furthermore, as shown in Figure 5 (described below), the rotating part 34b is movable in the direction in which the heater 33 expands and contracts. Therefore, it is preferable to form the rotating part 34b from a material that is less likely to generate particles even if friction occurs during movement. The rotating part 34b can be made from a metal such as stainless steel, for example.

FIG. 5 is a schematic diagram illustrating the function of the support portion 34. As shown in FIG.
As shown by the solid line in FIG. 5, when power is applied to the heater 33 (when ON), the heater 33 is heated by the generated heat, and therefore the heater 33 expands in the direction along the central axis.

As shown by the dashed dotted line in Figure 5, when the application of power to the heater 33 is stopped (OFF), the heated heater 33 cools, causing the heater 33 to contract in the direction along its central axis. Because the rotating part 34b is in contact with the heater 33, it moves in accordance with the expansion and contraction of the heater 33 in the direction along its central axis. In this case, because the rotating part 34b moves in a rotating manner, friction between the rotating part 34b and the heater 33 and between the rotating part 34b and the plate 34a2 can be reduced.

Furthermore, as mentioned above, the lower inner wall of the notch 34a3a of the guide plate 34a3 does not come into contact with the heater 33. Therefore, when the heater 33 expands and contracts in the direction along the central axis, no friction occurs between the lower inner wall of the notch 34a3a and the heater 33.

If there is no friction between the rotating part 34b and the heater 33, between the rotating part 34b and the plate 34a2, and between the lower inner wall of the notch 34a3a and the heater 33, the generation of particles can be suppressed.

4, a heat shield 65 can be provided between a frame 61 (described later) and the mounting plate 34a1. The heat shield 65 is provided to prevent heat from the heater 33 from being transmitted to the outside of the chamber 10. The provision of the heat shield 65 can improve heating efficiency and heat storage efficiency.

As shown in FIGS. 1 and 2, the holder 35 holds the vicinity of the end of the heater 33 outside the chamber 10 .
FIG. 6 is a schematic perspective view illustrating the holding portion 35. As shown in FIG.

As shown in FIG. 6 , the holding part 35 can be attached to the outer surface of the chamber 10 using, for example, a fastening member such as a screw. The holding part 35 detachably holds the vicinity of the end of the heater 33 on the terminal 33a side (the other end opposite the one end of the heater 33 supported by the support part 34 inside the chamber 10). The holding part 35 has, for example, a split clamping mechanism that tightens the inserted heater 33. When the holding part 35 holds the vicinity of the end of the heater 33 on the terminal 33a side, the terminal 33a of the heater 33 is exposed outside the chamber 10. In other words, the other end of the heater 33 penetrates the side surface of the chamber 10 and is provided outside the chamber 10.

If the terminal 33a of the heater 33 is exposed outside the chamber 10, maintenance of the heater 33 becomes easier. Furthermore, when power is applied to the heater 33, it is possible to prevent vacuum discharge from occurring at the terminal 33a of the heater 33.

Here, the heater 33 is provided to heat the entire area of the cassette 50 containing the workpiece 100. That is, the heater 33 heats the central and peripheral areas of the heating area where the workpiece 100 is heat-treated. For example, as shown in Figures 1 and 2, the tip of the heater 33 (the end on the support portion 34 side) is located outside the tip of the cassette 50 (the end on the support portion 34 side). With such a heater 33, the entire area of the workpiece 100 can be heated. However, heat from the workpiece 100 tends to escape from the peripheral side of the workpiece 100 to the outside, but it is difficult to escape from the center of the workpiece 100 to the outside. Therefore, even if the entire area of the workpiece 100 is heated by the heater 33, the temperature of the peripheral area of the workpiece 100 will be lower than the temperature of the central area of the workpiece 100. If the temperature difference between the peripheral area of the workpiece 100 and the central area of the workpiece 100 becomes large, the quality of the film or treatment layer formed on the surface of the workpiece 100 may be reduced.

The heat treatment apparatus 1 is therefore provided with a heater 36 that heats the peripheral region of the heating region where the workpiece 100 is heat-treated. For example, the heater 36 heats the vicinity of the peripheral region (e.g., only the peripheral region) of the cassette 50 in which the workpiece 100 is stored. In other words, the tip of the heater 36 (the end on the heating region side) is provided near the peripheral region of the heating region. At least one heater 36 can be provided. The heater 36 can be provided in at least one of the first heating section 31 and the second heating section 32.

The "central region of the heating region" is a region where the heat of the heated workpiece 100 is less likely to escape to the outside and where the temperature is less likely to drop due to heat escape during the heating process.
Furthermore, the "peripheral region of the heating region" is a region where heat from the heated workpiece 100 is likely to escape to the outside, and where a drop in temperature is likely to occur due to heat escape during heating processing. For example, the "peripheral region of the heating region" is the region excluding the "central region of the heating region" from the entire heating region. For example, the "peripheral region of the heating region" is the region (outer region) surrounding the "central region of the heating region."
The heater 33 heats the "central region of the heating region" and the "peripheral region of the heating region", that is, the entire heating region.
The heater 36 heats the "periphery of the heating area."
The "peripheral region of the heating region" and the "central region of the heating region" can be determined by actually measuring the in-plane temperature distribution of the workpiece 100 during heating treatment, or by simulating the in-plane temperature distribution of the workpiece 100 during heating treatment.

As shown in FIG. 2, heater 36 is arranged inside chamber 10, aligned with heater 33 along the Y direction. Heater 36 is rod-shaped and extends in one direction. There are no particular limitations on heater 36, as long as it is rod-shaped. As mentioned above, heater 33 heats the central and peripheral regions of the heating area. Heater 36 heats the peripheral region of the heating area. Therefore, the length of heater 36 is shorter than the length of heater 33. Note that the length of the heater is the length of the rod-shaped portion of the heater (excluding the wiring) in the direction in which the heater extends. In this case, if the power density of heater 36 is the same as that of heater 33, it becomes easy to make the surface temperatures of heaters 33 and 36 approximately the same and to make the lifespans of heaters 33 and 36 approximately the same. Other than its length, heater 36 can be similar to heater 33, for example.

For example, if multiple heaters 33 are arranged in the Y direction, at least one heater 36 can be arranged between the heaters 33 in the Y direction. In this case, the heater 36 may be parallel to the heater 33 or may be tilted relative to the heater 33. Furthermore, the position of the heater 36 in the Z direction may be the same as or different from the position of the heater 33.

Furthermore, as shown in Figure 2, a pair of heaters 36 can be provided facing each other in the direction in which the heaters 36 extend.

Here, heat in the peripheral region of the workpiece 100 is likely to escape from the edge of the peripheral region of the workpiece 100 to the outside, but is difficult to escape from the center of the peripheral region of the workpiece 100 to the outside. As a result, the temperature of the edge region of the peripheral region of the workpiece 100 is likely to be lower than the temperature of the center region of the peripheral region of the workpiece 100. In other words, even if a heater 36 is provided to reduce the difference in temperature between the peripheral region of the workpiece 100 and the center region of the workpiece 100, temperature variations may occur within the surface of the peripheral region of the workpiece 100.

If temperature variations occur within the surface of the peripheral region of the workpiece 100, at least one of the arrangement, number, and tip position of the heaters 36 can be changed. For example, at least one heater 36 can be provided between two adjacent heaters 33. In other words, there may be cases where no heater 36 is provided between two adjacent heaters 33. For example, at least one of the upper and lower central regions of the peripheral edge of the workpiece 100 can be provided with a portion where no heater 36 is provided, or with a small number of heaters 36. Alternatively, portions with a large number of heaters 36 can be provided at both ends in the Y direction.

Furthermore, between heaters 33, a heater 36 can be provided on one side of the direction in which the heaters 33 extend, and no heater 36 can be provided on the other side. For example, when viewed from the Z direction, multiple heaters 36 can be arranged in a staggered pattern.

FIG. 7 is a schematic diagram illustrating the arrangement of the heater 36. As shown in FIG.
7, the heater 36 can be provided in the same position as the heater 33 in the Z direction, or in a different position. For example, the heater 36 can be provided in the same position as the cassette 50 in the Z direction. Also, for example, a heater 36 provided in the same position as the heater 33 and a heater 36 provided in the same position as the cassette 50 in the Z direction can be provided together. Furthermore, the heater 36 provided in the same position as the cassette 50 in the Z direction can extend in a direction (e.g., Y direction) intersecting the direction in which the heater 33 extends (e.g., X direction).

As shown in FIG. 7, the tip of the heater 36 (the end on the heating area side) is provided near the periphery of the cassette 50 .
For example, when viewed from the Z direction, the position of the tip of the heater 36 may be outside the periphery of the cassette 50, may be overlapping with the periphery of the cassette 50, or may be inside the periphery of the cassette 50. In this case, the heater 36 heats the peripheral region of the heating area (near the periphery of the cassette 50). Therefore, when viewed from the Z direction, it is preferable that the position of the tip of the heater 36 be overlapping with the periphery of the cassette 50 or inside the periphery of the cassette 50. In this way, the vicinity of the periphery of the workpieces 100 stored in the cassette 50 can be efficiently heated.

FIG. 8 is a schematic diagram illustrating the tip position of the heater 36.
In FIG. 8, in order to avoid complication, the heater 33 is omitted and only the heater 36 is shown.
For example, when a plurality of heaters 36 are arranged in the Y direction, the tip positions of the plurality of heaters 36 may be the same or different in the direction in which the heaters 36 extend (for example, the X direction), as shown in Fig. 8. In this case, the tip positions of the plurality of heaters 36 can be changed as appropriate so as to reduce temperature variation in the peripheral region of the workpiece 100.

For example, as mentioned above, heat from the workpiece 100 is more likely to escape from the edges of the workpiece 100 to the outside than from the center of the workpiece 100. Therefore, the tip positions of the heaters 36 can be made closer to the inside of the cassette 50 as they approach the edges of the cassette 50 (workpiece 100). In other words, in a row of heaters 36 lined up in the Y direction, the tip (end on the heating area side) of the heater 32 provided at the end of the row can be positioned more inside the heating area than the tip (end on the heating area side) of the heater 36 provided at the center of the row. In this way, the heating range at the edge of the peripheral region of the workpiece 100 can be increased. Alternatively, the heating range at the center of the peripheral region of the workpiece 100 can be reduced. This reduces temperature variation in the peripheral region of the workpiece 100.

Temperature variation within the surface of the workpiece 100 is affected by the dimensions (planar dimensions) of the workpiece 100 when viewed from the Z direction, the heating temperature of the workpiece 100, and other factors. Therefore, it is preferable to appropriately determine the arrangement, number, and tip position of the heaters 36 through experiments and simulations so as to minimize temperature variation within the surface of the workpiece 100.

As mentioned above, the vicinity of the tip of heater 33 is supported by support parts 34 provided on frame 61 of cassette rack 60. However, the tip of heater 36 is provided near the periphery of cassette 50. Therefore, the vicinity of the tip of heater 36 cannot be supported by support parts 34 provided on frame 61 of cassette rack 60.

Therefore, a support portion 37 is provided to support the tip side of the heater 36. As shown in FIG. 6, the vicinity of the end of the heater 36 on the terminal 36a side (the side opposite the tip side of the heater 36) can be held by a holding portion 35, as in the case of the heater 33. When the holding portion 35 holds the vicinity of the end of the heater 36 on the terminal 36a side, the terminal 36a of the heater 36 is exposed outside the chamber 10.

9 and 10 are schematic views illustrating the support of the heater 36 by the support portion 37. FIG.
As shown in FIGS. 9 and 10, the support portion 37 has a mounting plate 37a, a plate 37b, and a holding portion 37c.

The mounting plate 37a is plate-shaped. The mounting plate 37a is attached to, for example, a beam 64 provided on the cassette rack 60 using fastening members such as screws.

Plate 37b is plate-shaped and extends toward heater 36. One end of plate 37b is connected to mounting plate 37a. Mounting plate 37a and plate 37b can be formed integrally, for example, by bending a plate material.

The holding portion 37c is band-shaped and holds the heater 36 using a fastening member such as a screw. The end of the plate 37b opposite the mounting plate 37a is connected to the holding portion 37c using a fastening member such as a screw.

The support portion 37 (mounting plate 37a, plate 37b, and holding portion 37c) is made of a heat-resistant material that is less likely to generate particles and is elastically deformable. For example, the support portion 37 can be made from a stainless steel plate approximately 0.5 mm thick.

When the heater 36 expands and contracts along its central axis when it is turned on and off, bending stress acts on the plate 37b via the retaining portion 37c. Because the plate 37b is made of an elastically deformable material, it functions as a leaf spring. That is, the plate 37b is connected to the retaining portion 37c and elastically deforms along the central axis of the heater 36 in response to the expansion and contraction of the heater 36.

If the plate 37b elastically deforms in a direction along the central axis of the heater 36, friction between the support portion 37 (holding portion 37c) and the heater 36 can be suppressed even if the heater 36 expands or contracts. This can prevent particles from being generated.

Note that, while the above example illustrates support portion 37 supporting heater 36, support portion 37 can also support heater 33, as described above. That is, heater 33 can be supported by support portion 34, by support portion 34 and support portion 37, or by support portion 37.

The cooling unit 40 cooperates with the cooling unit 57 provided in the cassette 50, which will be described later, to supply cooling gas to the cassette 50. The cooling gas supplied to the cassette 50 is supplied to the workpiece 100 stored inside the cassette 50. The cooling gas supplied to the cassette 50 is also supplied to the heat equalizer plates of the cassette 50 (upper heat equalizer plate 52, lower heat equalizer plate 53, side heat equalizer plate 54, side heat equalizer plate 55).

When cooling gas is supplied to the workpiece 100, the workpiece 100, which is in a high temperature state, is directly cooled. Furthermore, when the cooling gas supplied to the workpiece 100 is supplied to the heat equalizer plate of the cassette 50, the cassette 50 is also cooled. By cooling the cassette 50, the transfer of heat from the cassette 50 to the workpiece 100 can be suppressed. Therefore, the workpiece 100 is also indirectly cooled by the cassette 50.

As shown in Figures 1 and 2, the cooling unit 40 includes, for example, a joint 41, a gas source 42, and a gas control unit 43. The joint 41, the gas source 42, and the gas control unit 43 are connected by piping 44.

The joint 41 is detachably connected to a joint (not shown) of a cooling unit 57 provided in the cassette 50, for example.
The gas source 42 supplies cooling gas to the cooling section 57 of the cassette 50 via the gas control section 43 and the joint 41. The gas source 42 may be, for example, a high-pressure gas cylinder, factory piping, or the like.
There are no particular limitations on the cooling gas as long as it is a gas that does not easily react with the heated workpiece 100. Examples of the cooling gas include nitrogen gas and rare gas. The temperature of the cooling gas can be, for example, room temperature (e.g., 25°C) or lower.

The gas control unit 43 is provided between the joint 41 and the gas source 42. The gas control unit 43 can, for example, supply and stop the supply of cooling gas, and control at least one of the flow rate and flow rate of the cooling gas.

As shown in FIG. 1, the cassette 50 is detachably mounted on a pair of receiving members 62 of a cassette rack 60 provided inside the chamber 10. The cassette 50 is detachably mounted between the first heating unit 31 and the second heating unit 32.

FIG. 11 is a schematic perspective view illustrating the cassette 50. As shown in FIG.
As shown in Fig. 11, the cassette 50 has a box shape and has a heating area therein where the workpiece 100 is heated. In other words, the cassette 50 defines the heating area. There are no particular limitations on the external shape of the cassette 50. The external shape of the cassette 50 can be, for example, a rectangular parallelepiped.

The cassette 50 includes, for example, a cassette frame 51, an upper heat equalizer plate 52, a lower heat equalizer plate 53, side heat equalizer plates 54 and 55, a work support portion 56, a cooling portion 57, and a cassette support portion 58. Note that in Figure 11, the cooling portion 57 is omitted to avoid clutter (see Figure 1 for the cooling portion 57).

The cassette frame 51 defines a heating region for heating the workpiece 100. There are no particular limitations on the external shape of the cassette frame 51. The external shape of the cassette frame 51 is, for example, a rectangular parallelepiped.
The upper heat equalizer plate 52 has a plate shape and is provided on the upper part of the cassette frame 51. At least one upper heat equalizer plate 52 can be provided. The cassette 50 illustrated in FIG. 11 is provided with seven upper heat equalizer plates 52.

The lower heat equalizer plate 53 is plate-shaped and is provided at the bottom of the cassette frame 51. The lower heat equalizer plate 53 faces the upper heat equalizer plate 52. At least one lower heat equalizer plate 53 can be provided. The number and planar shape of the lower heat equalizer plates 53 can be the same as or different from the number and planar shape of the upper heat equalizer plates 52.

The side heat equalizer plates 54 are plate-shaped. A pair of side heat equalizer plates 54 can be provided. One side heat equalizer plate 54 is provided, for example, on one of the opposing sides of the cassette frame 51.

The workpiece 100 is carried into the cassette 50 through an opening provided in the side of the cassette frame 51. The workpiece 100 is also carried out from the cassette 50 through another opening provided in the side of the cassette frame 51. Therefore, one side of the pair of side heat equalizing plates 54 of the cassette frame 51 is open.

The opening of the cassette frame 51 is opened and closed by , for example, one of the side heat equalizer plates 54 having the opening , which is made openable and closable. For example, the side heat equalizer plate 54 may be provided on the opening door 13 of the chamber 10 described above, so that the opening of the cassette frame 51 is closed by the side heat equalizer plate 54 when the opening door 13 is closed.

The side heat equalizer plates 55 are plate-shaped and are provided as a pair inside the cassette frame 51. The pair of side heat equalizer plates 55 face each other and extend between the pair of side heat equalizer plates 54 (or, if there is only one side heat equalizer plate 54, between the side heat equalizer plate 54 on the lid 15 side and the opening on the opening door 13 side). One of the pair of side heat equalizer plates 55 is provided near one side of the cassette frame 51. The other of the pair of side heat equalizer plates 55 is provided near the other side of the cassette frame 51.

The space surrounded by the upper heat equalizer plate 52, lower heat equalizer plate 53, side heat equalizer plate 54, and side heat equalizer plate 55 becomes the heating area for heating the workpiece 100. The heating area inside the cassette 50 and the internal space of the chamber 10 are connected, for example, via gaps between the heat equalizer plates (gaps between the cassette beams and the heat equalizer plates that exist between the heat equalizer plates). Therefore, when the pressure in the internal space of the chamber 10 is reduced, the pressure in the internal space of the cassette 50 is also reduced.

In addition, the heat radiated from the heaters 33, 36 is incident on the upper heat equalizer plate 52 and the lower heat equalizer plate 53. The heat incident on the upper heat equalizer plate 52 and the lower heat equalizer plate 53 is radiated toward the workpiece 100 while propagating within them in the planar direction. This further reduces temperature variations within the surface of the workpiece 100.

Multiple workpiece support portions 56 are provided inside the cassette 50. The multiple workpiece support portions 56 support the back surface of the workpiece 100 in the heating region where the workpiece 100 is heated. The workpiece support portions 56 may be rod-shaped.

The cooling unit 57 supplies the cooling gas supplied from the cooling unit 40 to the workpiece 100 in the cassette 50. The cooling unit 57 can be provided, for example, on the side of the cassette frame 51.

The cassette support portion 58 is provided on the side of the cassette frame 51 that intersects with the side on which the side heat equalizer plate 54 is provided. A pair of cassette support portions 58 are provided. The cassette support portions 58 protrude outward from the side of the cassette frame 51 and extend in a direction perpendicular to the side on which the side heat equalizer plate 54 is provided.

A cassette support portion 58 is provided on each of a pair of opposing side surfaces of the cassette 50. The cassette support portion 58 is supported by a receiving member 62 of the cassette rack 60, which will be described later.

As shown in FIG. 3, the cassette rack 60 is provided inside the chamber 10. The cassette rack 60 holds the heater 33, the heater 36, and the cassette 50 in predetermined positions inside the chamber 10.

The cassette rack 60 includes, for example, a frame 61 , a receiving member 62 , and a reflector 63 .
The frame 61 has, for example, a framework structure. There are no particular limitations on the external shape of the frame 61. The external shape of the frame 61 can be, for example, a rectangular parallelepiped or a cylinder.

At least one pair of support members 62 is provided inside the frame 61. The pair of support members 62 supports the cassette support portion 58 of the cassette 50 inside the chamber 10. In the Z direction, the pair of support members 62 is provided between the first heating unit 31 and the second heating unit 32. One cassette 50 is placed on the pair of support members 62. Therefore, a pair of support members 62 is provided for each cassette 50. For example, if 14 cassettes 50 can be stored inside the frame 61, 14 pairs of support members 62 are provided inside the frame 61.

The reflector 63 reflects the incident heat toward the cassette 50. The presence of the reflector 63 can improve heat storage in the internal space (heated area) of the cassette 50. The reflector 63 is plate-shaped and is provided on the outer periphery of the frame 61. To avoid complexity, the reflector 63 is not depicted in Figures 1 and 2. Figure 3 only depicts the reflector 63 attached to the side of the frame 61 where the receiving member 62 is attached.

As mentioned above, heat in the peripheral region of the workpiece 100 is more likely to escape from the edge of the workpiece 100 to the outside than from the center of the workpiece 100 to the outside. In this case, as mentioned above, the temperature variation within the surface of the workpiece 100 can be reduced by adjusting the spacing between heaters 33, the arrangement, number, and tip position of heaters 36, etc. However, once this physical configuration is set, it is difficult to change. For this reason, in the heating unit 30 (first heating unit 31, second heating unit 32) mentioned above, the multiple heaters 33, 36 may be controlled separately in multiple regions.

For example, the heaters 33, 36 can be controlled in three separate areas: two areas near both ends of the workpiece 100 and one area in the center of the workpiece 100. In this case, the set temperatures of the two areas near both ends, where heat is likely to escape to the outside, can be set higher than the set temperature of the one central area.
In this way, the temperature variation within the surface of the workpiece 100 can be further reduced.

If heaters 33, 36 fail, they are replaced. When replacing heaters 33, 36, they are pulled out of chamber 10 and replaced with new heaters 33, 36. Therefore, a maintenance space longer than the length of heaters 33, 36 is required on the side of heat treatment device 1 (chamber 10) in the direction in which heaters 33, 36 extend. No items or equipment that would interfere with maintenance can be placed in the maintenance space.

2, the end of the heater 33 on the terminal 33a side is provided on one side of the chamber 10, and the tip of the heater 33 (the end opposite to the terminal 33a side) is provided on the opposite side of the chamber 10. This increases the length of the heater 33. As the length of the heater 33 increases, the maintenance space increases, and the actual space occupied by the heat treatment device 1 increases. Furthermore, when multiple heat treatment devices 1 are arranged side by side, the distance between the heat treatment devices 1 increases, which may reduce the number of heat treatment devices 1 that can be arranged.
As shown in FIG. 2, the length of the heater 36 is shorter than the length of the heater 33, so the length of the heater 36 has almost no effect on the size of the maintenance space.

FIG. 12 is a schematic cross-sectional view illustrating a heater 133 according to another embodiment.
The heater 133 is rod-shaped and extends in one direction. The configuration and arrangement of the heater 133 can be similar to those of the heater 33 described above. However, as shown in FIG. 12 , the length L of the heater 133 inserted into the chamber 10 can be less than half the distance W between the side surface 10a of the chamber 10 and the side surface 10b opposite the side surface 10a in the direction in which the heater 133 extends (e.g., the X direction). This shortens the length required to remove the heater 133 from the chamber 10, thereby reducing the maintenance space. Furthermore, by providing a pair of heaters 133 facing each other, it is possible to obtain the same heating effect as the heater 33 extending continuously above or below the cassette 50. Note that the heater 133 expands and contracts in a direction along the central axis when the heater 133 is turned on and off. Therefore, when a pair of heaters 133 facing each other is provided, a predetermined gap can be provided between the tips of the heaters 133. For example, a gap having a size sufficient to prevent the tips of the heaters 133 from contacting each other when the heaters 133 extend can be provided, which can prevent the tips of the heaters 133 from contacting each other when the heaters 133 extend, thereby preventing particles from being generated.
In this embodiment, the heater 36 can also be provided. In this case, the length of the heater 36 is shorter than the length of the heater 133.

Although Figure 12 illustrates a pair of heaters 133 facing each other, the position of the heater 133 provided on one side 10a of the chamber 10 may be different from the position of the heater 133 provided on the opposite side 10b of the chamber 10 in the direction in which the heaters 133 are arranged (e.g., the Y direction). For example, multiple heaters 133 may be arranged in a staggered pattern. The length of the heater 133 provided on one side 10a of the chamber 10 may be the same as or different from the length of the heater 133 provided on the opposite side 10b of the chamber 10.

In this embodiment, the pair of divided heaters 133 corresponds to the first heater. The heaters 133 are positioned so that the peripheral region and central region of the heating area are heated. Gaps may occur between the tips of the heaters 133, but these gaps do not extend over the entire central region of the heating area. Even if a gap occurs, the pair of heaters 133 will heat both the peripheral region and the central region of the heating area.

As mentioned above, temperature variation within the surface of the workpiece 100 is affected by the dimensions (planar dimensions) of the workpiece 100 when viewed from the Z direction, the heating temperature of the workpiece 100, and other factors. Therefore, it is preferable to appropriately determine the length, arrangement, number, and tip position of the heater 133 through experiments and simulations so as to minimize temperature variation within the surface of the workpiece 100.

FIG. 13 is a schematic view illustrating support of the heater 36 by a support portion 137 according to another embodiment.
As shown in FIG. 13, the support portion 137 has a pair of brackets 137a and a roller pin 137b.

The pair of brackets 137a can be provided facing each other with a predetermined gap between them. The pair of brackets 137a are attached to, for example, beams 64 provided on the cassette rack 60 using fastening members such as screws. Each of the pair of brackets 137a is provided with a hole 137a1 extending in the direction in which the heater 36 extends (for example, the X direction).
The roller pin 137b is rotatably provided in a hole 137a1 of the pair of brackets 137a. The heater 36 is provided on the roller pin 137b. That is, the heater 36 is supported by the roller pin 137b.

The support part 137 having the roller pin 137b has the same effect as the support part 34 described above. That is, when the heater 36 expands or contracts in a direction along the central axis, the roller pin 137b rotates and moves inside the hole 137a1 of the bracket 137a. This prevents friction from occurring between the roller pin 137b and the heater 36, and between the roller pin 137b and the inner wall of the hole 137a1. Preventing friction between these areas prevents particle generation.

Note that while support portion 137 supporting heater 36 is shown as an example, support portion 137 can also support heaters 33 and 133. Support portion 34, support portion 37, and support portion 137 can also be used in combination as appropriate.

Although the embodiments have been described above, the present invention is not limited to these descriptions.
Any design modifications made by a person skilled in the art to the above-described embodiments are also encompassed within the scope of the present invention as long as they include the features of the present invention.
For example, the shape, dimensions, and arrangement of the heat treatment device 1 are not limited to those exemplified and can be changed as appropriate. Furthermore, the elements of the above-described embodiments can be combined to the greatest extent possible, and such combinations are also included within the scope of the present invention as long as they include the features of the present invention.

1 Heat treatment device, 10 Chamber, 20 Exhaust section, 30 Heating section, 33 Heater, 34 Support section, 35 Holding section, 36 Heater, 37 Support section, 50 Cassette, 60 Cassette rack, 100 Workpiece, 133 Heater, 137 Support section

Claims (3)

a chamber having a heating region therein for heat-treating a workpiece;
a first heater provided inside the chamber above and/or below the heating region and extending in a first direction;
a second heater provided inside the chamber so as to be aligned with the first heater in a second direction intersecting the first direction and extending in the first direction ;
Equipped with
the first heater is configured as a single heater or a pair of heaters, and is arranged to heat a central region of the heating area and a peripheral region of the heating area in the first direction;
the second heater is configured as a pair of heaters, and the pair of heaters is arranged opposite to each other so as to heat the peripheral region of the heating region in the first direction ;
a plurality of the first heaters are provided and aligned in the second direction;
a plurality of the second heaters are provided and aligned in the second direction;
at least one second heater is provided between the first heaters in the second direction;
A heat treatment apparatus , wherein the lengths of one and the other of the pair of second heaters are both shorter than half the length in the first direction of the heating region heated by the first heater . 2. The heat treatment apparatus according to claim 1, wherein in a row of the second heaters arranged in the second direction, the position of the end of the second heater located at the end of the row on the side of the heating region is located more inward than the position of the end of the second heater located at the center of the row on the side of the heating region. The heat treatment device according to claim 1 or 2, further comprising a cassette disposed inside the chamber and defining the heating region.