KR19990006379A - Substrate Heat Treatment Equipment - Google Patents

Abstract

Provided is a substrate heat treatment apparatus that can easily change a heat treatment set temperature for a substrate.

The heating plate 1 of the substrate heating apparatus includes a substrate support plate 31 for supporting a substrate, an auxiliary heating unit 32 and a main heating unit 61, a heat transfer plate 60, and a water cooling jacket 36. do. The auxiliary heating part 32 and the main heating part 61 heat the water on the side of the water cooling jacket 36 at the time of heating the substrate W composed of the Peltier element, the main heating part 61, the heat transfer plate 60, and the auxiliary heating part. It transfers to the board | substrate support plate 31 through 32, and heats the board | substrate W. As shown in FIG. When the temperature of the substrate support plate 31 is lowered, the heat of the substrate support plate 31 is guided to the water cooling jacket 36 through the auxiliary heating unit 32, the heat transfer plate 60, and the main heating unit 61. It is discharged to the outside by cooling water.

Description

Substrate Heat Treatment Equipment

The present invention relates to a substrate heat treatment apparatus for processing a substrate at a predetermined temperature.

In substrate processing processes such as semiconductor wafers, glass substrates for photomasks, glass substrates for liquid crystal display devices, and substrates for optical disks, substrate heating apparatuses such as substrate heating apparatuses for heating substrates on which resist films are formed to a predetermined temperature and substrates after heating A substrate cooler that cools to a predetermined temperature is used.

It is a schematic diagram which shows the structure of the principal part of the conventional board | substrate heating apparatus. In Fig. 6, the substrate heating apparatus includes a heating plate 1 for heating the substrate W to a predetermined temperature. The heat source, such as a mica heater, is buried inside the heating plate 1. Moreover, the some spherical spacer 5 which supports the lower surface of the board | substrate W is arrange | positioned at the upper surface of the heating plate 1.

Below the heating plate 1, three lifting pins 3 and a lifting plate 6 connected to them are arranged. A cylinder 7 is connected to one end of the elevating plate 6, and the substrate W is moved up and down by three lifting pins 3 in accordance with the expansion and contraction operation of the rod of the cylinder 7.

The substrate heating apparatus is used, for example, for heat treatment before exposure to a resist film on a substrate (pre-baking), for heat treatment after exposure (PEB: Post Exposure Bake), for heat treatment after development (post-baking), and the like. The substrate W is sequentially supplied to the substrate heating apparatus at regular time intervals by a substrate transfer apparatus provided outside.

FIG. 7 is a diagram showing a thermal history of a substrate in the substrate heating apparatus of FIG. 6. In FIG. 7, when the substrate W on which the resist film is formed is placed on the heating plate 1 in the substrate heating apparatus, the temperature of the substrate W rises from room temperature to a predetermined temperature T1, for example, 110 ° C. do. Subsequently, the substrate W is maintained at the set temperature T1 during the predetermined heat treatment period and discharged to the outside through a predetermined waiting time.

In recent years, various types of resists have been used in accordance with the characteristics of patterns formed on the substrate W. As shown in FIG. The set temperature T1 of the heat treatment of the substrate W in the substrate heating apparatus depends on the type of resist. Therefore, when the substrate W coated with different kinds of resists is continuously supplied, the set temperature T1 of the substrate W is immediately changed in accordance with the type of resist of the substrate W to be supplied, and the substrate W is heated. It is desired to do this.

In the conventional board | substrate heating apparatus, the output of heat sources, such as a miter heater in the heating plate 1, is controlled and the set temperature T1 is adjusted. Therefore, when the set temperature T1 of the substrate W to be processed next is lower than the set temperature T1 of the immediately processed substrate W, the output of the heat source of the heating plate 1 is suppressed to It is necessary to lower the surface temperature.

However, the cooling plate is not provided with the heating plate 1. For this reason, in order to lower the temperature of the heating plate 1, it is inevitable to rely on natural heat radiation. By the way, the inside of a board | substrate heating apparatus is maintained in high temperature atmosphere, and the cooling effect by natural heat dissipation is extremely small. Therefore, the surface temperature of the heating plate 1 does not fall easily, and therefore it was difficult to continuously process the board | substrate W in which the preset temperature T1 differs.

Therefore, in the past, a plurality of substrate heating apparatuses were provided for each type of the set temperature T1 of the substrate W to perform heat treatment. For this reason, many board | substrate heating apparatus is needed and installation cost increases.

An object of the present invention is to provide a substrate heat treatment apparatus in which the set temperature of heat treatment on a substrate can be easily changed.

1 is a cross-sectional view of a substrate heating apparatus according to the present invention,

2 is a cross-sectional view of a heating plate according to an embodiment of the present invention;

3 is a flow chart of the temperature setting operation of the substrate heating apparatus having the heating plate of FIG.

4 is a flow chart of a high temperature rise operation,

FIG. 5 is a diagram illustrating a temperature change of a substrate in the high temperature rising operation of FIG. 4;

6 is a schematic diagram showing the configuration of main parts of a conventional substrate heating apparatus;

7 is a diagram showing a thermal history of a substrate in the substrate heating apparatus.

Explanation of symbols for the main parts of the drawings

1 heating plate, 31 substrate support plates,

32 sub-heaters, 36 water cooling jackets,

37 cooling water passage, 53 air cooling jacket,

54 air passages, 60 heat transfer plates,

61 Main heating part.

The substrate heat treatment apparatus according to the first invention is a substrate heat treatment apparatus for treating a substrate at a predetermined temperature, the substrate heat treatment apparatus supporting a substrate, a heat transfer member disposed below the substrate support, and a heat transfer member disposed below the substrate support. The first heat exchange means disposed between the cooled portion, the substrate support and the heat transfer member to perform heat exchange between the substrate support and the heat transfer member, and between the heat transfer member and the cooling portion, It is provided with the 2nd heat exchange means which heat-exchanges.

In the substrate heat treatment apparatus according to the first invention, the second heat exchange means moves the heat to the heat transfer member side to raise the temperature of the heat transfer member, and the first heat exchange means moves the heat from the heat transfer member to the substrate support side. This raises the substrate support to a predetermined temperature. Thereby, the temperature of the board | substrate supported by the board | substrate support object can be correctly set to predetermined temperature.

In addition, when lowering the set temperature of the substrate, the first heat exchange means moves heat from the substrate support to the heat transfer member side, and the second heat exchange means moves heat from the heat transfer member to the cooling section. The cooling unit releases the transferred heat to the outside. By this action, the temperature of the substrate support can be lowered quickly. As a result, it is possible to continuously process a substrate having a high set temperature during heating and a substrate having a low temperature by the same substrate heat treatment apparatus, thereby reducing the cost of equipment in the heat treatment and at the same time increasing the efficiency of the heat treatment. Can improve.

In the substrate heat treatment apparatus according to the second invention, in the configuration of the substrate heat treatment apparatus according to the first invention, the first and second heat exchange means are Peltier elements.

The Peltier element can change the moving direction of heat by performing an operation of moving heat by the thermoelectric effect, and switching the direction of the supplied electric current. As a result, heat is moved to the substrate support side when the temperature of the substrate support is increased, and heat is moved from the substrate support to the cooling unit side when the temperature of the substrate support is decreased. Thereby, the temperature of a board | substrate support stand can be correctly set to predetermined temperature.

In the board | substrate heat treatment apparatus which concerns on 3rd invention, in the structure of the board | substrate heat treatment apparatus which concerns on 1st or 2nd invention, the cooling part is arrange | positioned in contact with the lower surface of a 2nd heat exchange means, and the channel | path which lets cooling water pass inside It is composed of a cooling member formed.

The heat guided to the second heat exchange means is released to the outside by the cooling water passing through the cooling member. As a result, the heat of the substrate support can be forcibly released to lower the temperature.

Embodiment of the Invention

1 is a cross-sectional view of a substrate heating apparatus according to an embodiment of the present invention. The substrate heating apparatus includes a heating plate 1 for heating the substrate W inside the case 10. On the upper surface of the heating plate 1, three spherical spacers 5 supporting the lower surface of the substrate W are arranged in an equilateral triangle shape. The heating plate 1 is also provided with three through holes 4 for passing three lifting pins 3 for moving the substrate W up and down.

Above the heating plate 1, an upper cover 2 covering the upper surface of the heating plate 1 is attached inside the upper surface of the case 10. As shown in FIG. In addition, three lifting pins 3 which support the lower surface of the substrate W and move up and down are disposed under the heating plate 1 and the lifting plate 6 connected to these. The cylinder 7 is connected to the end of the elevating plate 6 from the outside of the case 10. Then, the lifting plate 6 and the lifting pins 3 move up and down by the expansion and contraction of the rod of the cylinder 7. The substrate W waits above the heating plate 1 when the lifting plate 6 and the lifting pins 3 are raised, and the substrate W is a spherical spacer on the heating plate 1 when the lifting plate 6 and the lifting pins 3 are raised. It is put on (5).

The substrate supply / discharge port 11 is formed in the front surface of the case 10. The shutter 9 is arranged inside the substrate supply / exhaust port 11. The lower end of the shutter 9 is connected to the elevating plate 6 by an interlocking member 8. As a result, when the rod of the cylinder 7 extends, the elevating plate 6 is raised to lift the substrate W to the standby position, and the shutter 9 is lowered to open the substrate supply / discharge port 11. do. Further, when the rod of the cylinder 7 is accommodated, the elevating plate 6 is lowered to place the substrate W on the spherical spacer 5 and the shutter 9 is raised to raise the substrate supply / discharge port. (11) is closed.

2 is a cross-sectional view of the heating plate. The heating plate 1 of FIG. 2 includes a substrate support plate 31, an auxiliary heating unit 32 provided on the lower surface of the substrate support plate 31, and a heat transfer plate 60 provided on the lower surface of the auxiliary heating unit 32. And a main body 61 provided on the lower surface of the heat transfer plate 60 and a water cooling jacket 36 provided on the lower surface of the main heating portion 61.

The substrate support plate 31 is made of a material having good heat transfer properties such as aluminum, and three spherical spacers 5 for supporting the substrate W on the upper surface thereof are arranged in an equilateral triangle shape. By controlling the surface temperature of this board | substrate support plate 31 to predetermined temperature, the temperature of the board | substrate W supported by the some space | interval above the board | substrate supporting plate 31 at a predetermined interval is adjusted to predetermined | prescribed set temperature. .

The auxiliary heating unit 32 is composed of a Peltier element. The Peltier element absorbs heat from one side and releases heat from the other side by supplying current. This can move heat. The moving direction of the heat can be switched by changing the direction of the current to be supplied. Therefore, when raising the temperature on the substrate support plate 31 side, the heat is transferred from the heat transfer plate 60 to the substrate support plate 31 side, and when the temperature of the substrate support plate 31 is lowered, the substrate is supported. Heat is moved from the plate 31 to the heat transfer plate 60 side. The auxiliary heating part 32 using this Peltier element can adjust the temperature of the board | substrate support plate 31 in a short time.

The heat transfer plate 60 is made of a plate-shaped member having good heat transfer property, and serves to uniformize heat from the main heating portion 61 and transfer it to the substrate support plate 31.

The main heating unit 61 is composed of a Peltier element. The Peltier element moves the heat on the water cooling jacket 36 side to the heat transfer plate 60 side at the time of heating, and transfers the heat on the heat transfer plate 60 side when the temperature of the substrate support plate 31 is lowered. Go to 36).

The water cooling jacket 36 is provided with a cooling water passage 37 for circulating the cooling water in the plate-shaped member having good heat transfer property. The cooling water passage 37 is connected to the cooling water supply source 51 of the factory where the substrate heating apparatus is arranged, for example, through the circulation pipe 38.

Moreover, the board | substrate support plate 31 is provided with the board | substrate detection sensor 39 which detects that the board | substrate W was thrown in on the board | substrate support plate 31. As shown in FIG. The output of the substrate detection sensor 39 is input to the main controller 48. In addition, the substrate support plate 31 is provided with a temperature detection sensor 40, and this sensor output is input to the first temperature controller (T.C.) 45.

The heat transfer plate 60 is provided with a temperature detection sensor 41, and this sensor output is input to the second temperature controller 46. The first and second temperature controllers 45 and 46 control currents supplied from the power source 50 to the auxiliary heating unit 32 and the main heating unit 61, respectively. The operation of the first and second temperature controllers 45, 46 is controlled by the main controller 48.

The main controller 48 includes a microcomputer having a CPU (central processing unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a counter for measuring time, and the like. The main controller 48 is also connected with an input unit 49 made of a keyboard or the like for inputting temperature control conditions.

In the substrate heating apparatus, the substrate support plate 31 corresponds to the substrate support of the present invention, the heat transfer plate 60 corresponds to the heat transfer member, the water cooling jacket 36 corresponds to the cooling section and the cooling member, The auxiliary heating portion 32 corresponds to the first heat exchange means, and the main heating portion 61 corresponds to the second heat exchange means.

Next, the operation of the substrate heating apparatus will be described. Hereinafter, (1) temperature setting operation | movement of a board | substrate supporting plate, (2) high speed temperature raising operation | movement at the time of board | substrate input, and (3) operation | movement of temperature change (temperature fall) are demonstrated.

(1) Temperature setting operation of substrate support plate

3 is a flowchart of the temperature setting operation of the substrate heating apparatus. Here, suppose that the upper surface temperature of the support plate 31 is set to 110 degreeC.

As shown in FIG. 3, before carrying in the board | substrate W, the main heating part 61 is driven and the process of step S1 and step S2 is performed. At the same time, the auxiliary heating unit 32 is driven to perform the processing of step S3 and step S4.

That is, in step S1, the 2nd temperature controller 46 supplies electric current from the power supply 50 to the Peltier element of the main heating part 61, and moves the heat of the water cooling jacket 36 side to the heat transfer plate 60 side. Let's do it. Then, the main controller 48 monitors the temperature of the heat transfer plate 60 based on the output from the temperature detection sensor 41, and determines whether the heat transfer plate 60 has reached a predetermined temperature (for example, 60 ° C). (Step S2). When the heat transfer plate 60 is below a predetermined temperature, the amount of current to the Peltier element of the main heating unit 61 is adjusted by the second temperature controller 46, and when the predetermined temperature is reached, the main heating unit 61 Switch the current direction to the Peltier device. The Peltier element can change the direction of movement of heat by changing the direction of the supplied current. This process is repeated and the temperature of the heat exchanger plate 60 is kept at 60 degreeC.

In parallel with the above operation, in step S3, a current is supplied from the power supply 50 to the auxiliary heating unit 32, and the temperature of the substrate support plate 31 is raised by the thermal movement action of the Peltier element. The main controller 48 judges whether or not the temperature of the substrate support plate 31 has reached a predetermined temperature, that is, 110 ° C, based on the output from the temperature detection sensor 40 of the substrate support plate 31 (step S4). ). If it is not 110 ° C, the current supply direction of the Peltier element is appropriately switched to adjust the temperature of the substrate support plate 31 to be 110 ° C.

In the temperature setting process, the temperature setting of the substrate support plate 31 is performed by the Peltier element of the main heating unit 61 and the Peltier element of the auxiliary heating unit 32. The heat transfer control by the Peltier element can be performed accurately and in a short time. Therefore, compared with the case where the temperature adjustment of the board | substrate support plate 31 is performed using a heater, it can carry out more correctly within a short time.

(2) High speed temperature rise operation at substrate input

In the temperature setting process, when the substrate W is introduced onto the substrate support plate 31 set to a predetermined temperature, for example, 110 ° C., the substrate W at the time of loading is low as room temperature, so that the substrate The surface temperature of the support plate 31 drops rapidly. Thus, the following high temperature rise operation is performed, and the surface temperature of the substrate support plate 31 is corrected to set the substrate to a desired temperature.

4 is a flowchart of a high speed temperature increase operation when the temperature of the substrate is controlled to 110 ± 0.3 ° C. 5 is a view showing a temperature change of the substrate.

In the state where the substrate support plate 31 is controlled at 110 ° C., for example, when the substrate W at room temperature (about 23 ° C.) is put on the substrate support plate 31, the substrate is supported as shown in FIG. 5. The temperature of the plate 31 drops rapidly. Therefore, first, it is judged by the output from the temperature detection sensor 41 whether the temperature of the board | substrate supporting plate 31 fell more than 0.5 degreeC (step S10).

When the temperature drop of 0.5 ° C. or more is detected, the first temperature controller 45 is controlled, and the maximum allowable current is supplied to the auxiliary heating unit 32. Thereby, the temperature of the board | substrate support plate 31 is raised by what is called full power. The main controller 48 monitors the temperature rise state of the substrate support plate 31. The maximum allowable current is supplied to the auxiliary heating unit 32 until the temperature of the substrate supporting plate 31 reaches 110 ° C (step S11).

When the temperature of the board | substrate supporting plate 31 reaches 110 degreeC (step S12), the 1st temperature controller 45 is switched to PID control and the temperature rise operation is suppressed. Then, the temperature raising and the temperature lowering operation are performed while controlling the direction of the current supplied to the auxiliary heating unit 32, and the temperature rising of the substrate supporting plate 31 is controlled in the range of 110 ° C ± 0.3 ° C (step S13). .

In the above-described high speed temperature increase operation, since the auxiliary heating unit 32 is formed of a Peltier element, even when the temperature of the substrate W is overshooted by performing the temperature increase operation at full power, it is agile. By switching to the temperature drop processing, the temperature of the substrate W can be adjusted to a desired set temperature in a short time and in a controlled manner.

(3) Change of temperature setting (temperature drop)

Next, the operation when the set temperature of the object to be processed is lower than the set temperature of the immediately preceding substrate will be described. The temperature of the substrate support plate 31 after the heat treatment is almost in the same state as the set temperature of the immediately preceding substrate, for example, 110 ° C. Similarly, the temperature of the heat transfer plate 60 is maintained near 60 degreeC.

Thus, the main controller 48 drives the Peltier element of the auxiliary heating unit 32 and the Peltier element of the main heating unit 61 by the first temperature controller 45 and the second temperature controller 46. A current is supplied to the Peltier element of the auxiliary heating part 32 to move the heat of the substrate support plate 31 toward the heat transfer plate 60 side, and the heat of the heat transfer plate 60 is supplied to the Peltier element of the main heating part 61. Current is supplied to move to the water cooling jacket 36 side. As a result, the heat of the substrate supporting plate 31 is transferred to the water cooling jacket 36 through the Peltier elements of the auxiliary heating unit 32, the heat transfer plate 60, and the main heating unit 61. The transferred heat is discharged to the outside by the cooling water circulating in the cooling water passage 37 of the water cooling jacket 36. Thereby, the temperature of the board | substrate supporting plate 31 falls rapidly. In addition, the cooling water of the water cooling jacket 36 may always be circulated.

Thus, by using Peltier elements for the main heating part 61 and the auxiliary heating part 3, the board | substrate supporting plate 31 can be raised to predetermined temperature, and it can fall quickly. Thereby, even when the board | substrate with a high set temperature of heat processing and a low board | substrate are supplied continuously, the heat processing can be performed by converting the upper surface temperature of the board | substrate support plate 31 agility.

As explained above, according to this invention, there exists an effect that the temperature of the board | substrate supported by the board | substrate support object can be correctly set to predetermined temperature. In addition, it is possible to rapidly lower the temperature of the substrate support, and it is possible to continuously process a substrate having a high set temperature at the time of heating and a substrate having a low temperature by the same substrate heat treatment apparatus. At the same time, there is an effect that the efficiency of the heat treatment can be improved.

Further, according to the present invention, there is an effect that the temperature can be lowered by forcibly releasing the heat of the substrate support.

Claims (3)

In the substrate heat treatment apparatus for processing the substrate at a predetermined temperature, A substrate support for supporting a substrate, A heat transfer member disposed below the substrate support; A cooling unit disposed below the heat transfer member; First heat exchange means disposed between the substrate support and the heat transfer member and performing heat exchange between the substrate support and the heat transfer member; Second heat exchange means disposed between the heat transfer member and the cooling unit and performing heat exchange between the heat transfer member and the cooling unit; Substrate heat treatment apparatus comprising a. According to claim 1, And said first and second heat exchange means are Peltier elements. The method according to claim 1 or 2, And said cooling portion is formed in contact with a lower surface of said second heat exchange means and comprises a cooling member formed therein with a passage through which cooling water passes.