JPH0845817A - Baking equipment - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a baking apparatus, and an object thereof is to improve dimensional accuracy and resolution of a pattern. [Structure] The gas displacement tank 12, the baking tank 13, and the substrate cooling tank 14 are the outer circumferences of the hot plates 21 and 51, and
Insulating covers 25, 31, 5 for covering the periphery of the semiconductor substrate 81
5, 5 and a partition wall 5 having vacuum layers 57 and 63 inside
6,62. The semiconductor substrate 81 exposed for pattern formation after resist coating is
The temperature is controlled to a constant temperature. After this, the semiconductor substrate 81
Is placed on the hot plate 51 having the heater 53 built therein in the baking tank 13 and baked at a constant temperature,
After that, the substrate is cooled rapidly to room temperature in the substrate cooling tank 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a baking device,
In particular, the present invention relates to a baking apparatus that heat-treats a semiconductor substrate coated with a resist.

In pattern formation using a chemically amplified resist, a semiconductor substrate coated with the chemically amplified resist is exposed by an electron beam or the like and then heated by a baking device to form a resin on the exposed portion. The dimensional accuracy of the resin formation determines the dimensional accuracy and resolution of the pattern. In this baking apparatus, it is necessary to improve the dimensional accuracy and resolution of the pattern.

[0003]

2. Description of the Related Art Recently, a chemically amplified resist has been used in the formation of fine patterns. FIG. 4 is an explanatory diagram of pattern formation using a chemically amplified resist.

As shown in FIG. 4A, when a portion of a semiconductor substrate (hereinafter, simply referred to as a substrate) 81 coated with a chemically amplified resist 101, on which a pattern is formed, is exposed by an electron beam or the like, Acid is generated in the exposed portion 102. After this, post exposure bake (P
By EB), the resin is crosslinked by using the generated acid as a catalyst. In PEB, the substrate 81 is baked at an optimum temperature using a hot plate. After the baking is finished, the substrate 81 is gradually cooled, and then a development process is performed to remove unnecessary portions of the resist to form a pattern. FIG. 4B shows the pattern 1 formed on the exposed portion of the substrate 81 after the development processing.
03 is shown.

[0005]

When a chemically amplified resist is used, the diffusion state of the acid generated in the exposed portion changes depending on the temperature during baking, and the portion where the resin is crosslinked changes correspondingly. . Therefore, the dimensional accuracy and resolution of the pattern are greatly affected by the baking temperature.

The baking apparatus is provided with a cover for covering the periphery of the hot plate of the baking tank in order to stabilize the temperature during baking. However, the conventional baking apparatus has a problem in that the heat insulation of the cover and the like is insufficient, the temperature of the atmosphere in the baking tank becomes uneven, and the pattern dimensional accuracy and resolution are degraded.

Further, in the conventional baking apparatus, the temperature distribution of the hot plate in the baking tank is not uniform, and the temperature of the outer peripheral portion of the hot plate becomes lower than the temperature of the central portion, and due to this temperature difference, the temperature difference within the substrate surface is increased. There are problems that the dimensional accuracy of the pattern decreases and the distribution of resolution occurs.

The substrate temperature before starting the baking affects the substrate temperature at the time of baking and changes the diffusion state of the acid. FIG. 5 is an explanatory diagram of the relationship between the substrate temperature during baking and the pattern formed.

If the substrate temperature during baking is appropriate,
The acid is optimally diffused during baking, and as shown in FIG. 5A, the pattern 103a having the best dimensional accuracy is formed.

When the substrate temperature during baking is higher than the optimum temperature, the diffusion of acid during baking proceeds too much, and the formed pattern 103b is formed as shown in FIG. 5B.
Causes the pattern width to widen and the dimensional accuracy to deteriorate.

When the substrate temperature during baking is lower than the optimum temperature, the acid diffusion during baking does not proceed sufficiently,
As shown in FIG. 5C, the formed pattern 103c
, The pattern width becomes narrow and the dimensional accuracy becomes poor.

In the conventional baking apparatus, the substrate before starting the baking waits immediately before the baking tank, so that the temperature of the baking tank affects the substrate temperature. Especially, since the standby time is not constant, the temperature rise of the substrate also changes. Therefore, the dimensional accuracy of the pattern,
There is a problem that the resolution becomes poor.

Further, in the conventional baking apparatus, since the substrate is naturally cooled after completion of baking, the acid diffusion proceeds, and the pattern dimensional accuracy and resolution are deteriorated.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a baking apparatus capable of controlling the temperature of a semiconductor substrate with high accuracy and improving the dimensional accuracy and resolution of a pattern. To aim.

[0015]

The above-mentioned problems can be solved by the following means.

According to a first aspect of the present invention, there is provided a baking apparatus in which a semiconductor substrate exposed for pattern formation after resist application is placed on a hot plate containing a heater in a baking tank and baked, and the outer periphery of the hot plate, and A heat insulating cover that covers the periphery of the semiconductor substrate placed on the hot plate is formed by partition walls having a vacuum layer inside.

According to a fourth aspect of the present invention, in the hot plate, the unit of the heater is increased from the central portion to the outer peripheral portion of the hot plate so as to compensate for the non-uniformity of heat dissipation characteristics on the hot plate. The amount of heat generated per area is increased.

According to a fifth aspect of the present invention, a plurality of temperature sensors are provided inside the heater, and the temperature of the heater is controlled by a heater temperature controller based on the temperatures detected by the temperature sensors, and the hot plate is heated. The temperature is controlled to a predetermined value.

According to a sixth aspect of the invention, a plurality of temperature sensors are provided in the space surrounded by the heat insulating cover in the vicinity of the semiconductor substrate, and the ambient temperature is determined based on the temperature detected by each of the temperature sensors. The controller controls the temperature of the gas filled in the space to control the temperature near the surface of the semiconductor substrate to a predetermined value.

According to a seventh aspect of the present invention, the hot plate circulates cooling water whose temperature is controlled to a constant temperature, and the partition wall having a vacuum layer inside, and is formed on the outer periphery of the hot plate and the hot plate. And a heat insulating cover that covers the periphery of the semiconductor substrate placed on the heat insulating cover, and a gas replacement layer filled with a gas whose temperature is controlled to a constant temperature is provided in a space surrounded by the heat insulating cover. Before the baking of the semiconductor substrate is started, the surface temperature of the semiconductor substrate is controlled to a constant temperature in the gas displacement tank.

According to the invention of claim 8, the hot plate is provided with a circulating hot water controlled at a constant temperature and a partition having a vacuum layer therein, and the outer periphery of the hot plate and the hot plate are formed. And a heat insulating cover that covers the periphery of the semiconductor substrate placed on the substrate, and a substrate cooling tank filled with a gas whose temperature is controlled to a constant temperature is provided in the space surrounded by the heat insulating cover. After the baking is completed, the surface temperature of the semiconductor substrate is rapidly cooled to a constant temperature in the substrate cooling tank. King device.

[0022]

According to the invention of claim 1, since the heat insulating cover has the vacuum layer, the heat insulating property of the heat insulating cover is extremely excellent, and the heat radiation from the heat insulating cover can be extremely reduced. The temperature and the temperature of the atmosphere in the baking tank can be stabilized with high accuracy.

According to the fourth aspect of the invention, since the heater compensates for the heat radiation characteristic of the hot plate, the entire hot plate can be controlled to a uniform temperature.

According to the invention of claim 5, the heater temperature is controlled based on the temperatures detected by a plurality of temperature sensors provided inside the heater incorporated in the hot plate. Therefore, the temperature of the hot plate is controlled with high accuracy. It is possible.

According to the sixth aspect of the invention, the temperature of the gas filled in the space surrounded by the heat insulating cover is controlled based on the temperatures detected by the plurality of temperature sensors provided close to the semiconductor substrate. It is possible to control the temperature near the surface of the semiconductor substrate with high accuracy.

According to the seventh aspect of the present invention, the surface temperature of the semiconductor substrate can be controlled to a constant temperature with high accuracy in the gas replacement tank before the baking is started in the baking tank.
Therefore, the temperature of the semiconductor substrate during baking can be set to the optimum temperature.

According to the present invention, after the semiconductor substrate is baked, the surface temperature of the semiconductor substrate is rapidly cooled to a constant temperature in the substrate cooling tank. For this reason, it is possible to reduce a change due to the temperature of the resist during cooling, and it is possible to improve dimensional accuracy and resolution of the pattern.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a baking apparatus 1 according to an embodiment of the present invention.
The block diagram of 1 is shown. The baking device 11 includes a gas replacement tank 12 for controlling the temperature of the substrate before baking to a temperature, a baking tank 13, a substrate cooling tank 14 for cooling the substrate after baking, and a transfer device 17. For example, the transport device 17 includes a transport belt 19 on which the substrate 81 is placed and a rotating roller 18 that drives the transport belt 19. In addition, in FIG. 1, the gas replacement tank 12 and the baking tank 1 are shown.
3, the substrate cooling tank 14 is shown in a cross-sectional view as viewed from the side.

The gas replacement tank 12 is generally a hot plate.
21, lower cover 25, upper cover 31, cooling water circulator 4
2, cooling water temperature controller 41₁, Temperature sensor 43, atmosphere temperature control
Bowl 45 ₁, A temperature sensor 48.

Inside the hot plate 21, a water passage continuing to the circulation passage 42a of the cooling water circulator 42 is provided passing near the upper surface 21a of the hot plate 21. Cooling water circulates through this water passage by the cooling water circulator 42.

A plurality of temperature sensors 43 are arranged near the upper surface 21a of the hot plate 21. Cooling water temperature controller 4
1 ₁ is a hot plate 2 detected by the temperature sensor 43
Based on the temperature near the upper surface 21a of _{No. 1} , the heating amount to the cooling water temperature controller 41 ₁ is controlled so that the temperature of the cooling water circulating near the upper surface 21a of the hot plate 21 becomes a constant temperature. As a result, the temperature of the upper surface 21a of the hot plate 21 is adjusted to a constant temperature with high accuracy.

The outer periphery of the hot plate 21 has a lower cover 2
Covered with 5. The lower cover 25 has a vacuum layer 27 inside.
It is formed by the partition wall 26 having. The partition wall 26 is made of a material having an excellent heat insulating property, for example, metal, ceramic, glass or the like.

The upper cover 31 that covers the periphery of the upper surface 21a of the hot plate 21 on which the semiconductor substrate 81 is mounted is formed by the partition walls 32 having the vacuum layer 33 inside. The partition wall 32 is formed of a material having an excellent heat insulating property, for example, metal, ceramic, glass or the like. Further, a reflection plate 34 that reflects heat is provided on the inner surface side of the upper cover 31.

The nitrogen gas whose temperature is adjusted by the atmosphere temperature controller 45 ₁ is filled into the space surrounded by the upper cover 31 by the introduction path 47. As a result, the gas in this space is replaced with nitrogen gas.

A plurality of temperature sensors 48 are arranged in proximity to the substrate 81 placed on the upper surface 21a of the hot plate 21, and the lead wire 49 is used to provide an atmosphere temperature controller 45 ₁
It is connected to the. The temperature sensor 48 can be arranged at an optimum position by adjusting the length of the lead wire 49.

The atmosphere temperature controller 45 ₁ controls the temperature of the nitrogen gas to be filled so that the temperature near the surface of the substrate 81 detected by the temperature sensor 48 becomes a constant temperature. As a result, the ambient temperature near the surface of the substrate 81 is adjusted to a constant temperature with high accuracy.

As described above, the hot plate 21 is highly accurately adjusted to a constant temperature near the upper surface 21a by the cooling water adjusted to a constant temperature, and the atmosphere around the upper surface 21a is temperature controlled. The temperature is adjusted to a constant temperature with a high accuracy by using, for example, nitrogen gas.

Further, since the upper cover 31 and the lower cover 25 have the vacuum layers 33 and 27, they have excellent heat insulating properties. Further, the reflection plate 34 on the inner surface side of the upper cover 31 reflects heat. Therefore, heat radiation from the hot plate 21 and the atmosphere above the hot plate 21 through the lower cover 25 and the upper cover 31 can be extremely reduced.

From the above, in the gas displacement tank 12, the substrate 81 placed on the upper surface 21a of the hot plate 21 can be controlled to a constant temperature with high accuracy.

Since the substrate 81 is carried by, for example, being carried on the carrying belt 19 of the carrying device 17, a groove through which the carrying belt 19 passes is provided on the upper surface 21a of the hot plate 21. The conveyor belt 19 is composed of, for example, two thin belts arranged in parallel at a predetermined interval.

The baking tank 13 generally has a hot plate 51, a lower cover 55, an upper cover 61, and a heater temperature controller 7.
1, temperature sensor 73, atmosphere temperature controller 75, temperature sensor 7
It consists of 8.

Inside the hot plate 51, a heater 53 for heating the hot plate 51 is mounted near the upper surface 51a of the hot plate 51.

A plurality of temperature sensors 73 are arranged inside the heater 53 near the upper surface 51a of the hot plate 51. The heater temperature controller 71 controls the temperature of the heater 53 on the basis of the temperature near the upper surface 51 a of the hot plate 51 detected by the temperature sensor 73, and the hot plate 51 is controlled.
The temperature of the upper surface 51a is adjusted to a specified baking temperature. In this way, the upper surface 51a of the hot plate 51
The temperature of is accurately adjusted to the specified baking temperature.

The outer periphery of the hot plate 51 has a lower cover 5
Covered with 5. The lower cover 55 has a vacuum layer 57 inside.
It is formed by the partition wall 56 having a. The partition wall 56 is formed of a material having an excellent heat insulating property, for example, metal, ceramic, glass or the like.

The upper cover 61 that covers the periphery of the upper surface 51a of the hot plate 51 on which the semiconductor substrate 81 is mounted is formed by partition walls 62 having a vacuum layer 63 inside. The partition wall 62 is made of a material having an excellent heat insulating property, for example, metal, ceramic, glass or the like. A reflection plate 64 is provided on the inner surface of the upper cover 61.

For example, nitrogen gas whose temperature has been adjusted by the atmosphere temperature adjuster 75 is filled in the space surrounded by the upper cover 61 by the introduction path 77.

A plurality of temperature sensors 78 are arranged close to the substrate 81 placed on the upper surface 51a of the hot plate 51, and are connected to the atmosphere temperature controller 75 by lead wires 79. The temperature sensor 78 can be arranged at an optimum position by adjusting the length of the lead wire 79.

The ambient temperature controller 75 controls the temperature of, for example, nitrogen gas to be filled so that the temperature near the surface of the substrate 81 detected by the temperature sensor 78 becomes a specified baking temperature. As a result, the ambient temperature near the surface of the substrate 81 is adjusted to the baking temperature with high accuracy.

On the upper surface 51a of the hot plate 51, a groove through which the conveyor belt 19 of the conveyor 17 passes is provided.

FIG. 2 is an explanatory view of various examples of the heater 53. The heater 53 _{1 in} FIG. 2A is the hot plate 51.
A heater wire 53 _1a is concentrically arranged inside.

The hot plate 51 has a characteristic that the heat radiation property increases from the central portion toward the outer peripheral portion. In order to compensate for this heat dissipation characteristic, the heat generation amount per unit area of the heater 53 ₁ is increased from the central portion of the hot plate 51 toward the outer peripheral portion.

In the heater 53 ₂ of FIG. 2B, heater wires 53 _2a are radially arranged in the hot plate 51. To compensate for the heat dissipation characteristics of the hot plate 51,
The heating amount per unit area of the heater 53 ₂ is increased from the central portion of the hot plate 51 to the outer peripheral portion thereof.

In the heater 53 ₃ of FIG. 2C, a concentric heater wire 53 _3a and a radial heater wire 53 _3b are arranged in the hot plate 51. Hot plate 51
In order to compensate for the heat dissipation characteristic of the hot plate 51, the heat generation amount per unit area of the heater 53 ₃ is increased from the central portion of the hot plate 51 toward the outer peripheral portion.

[0054] The heater 53 ₄ of FIG. 2 (D) in the hot plate 51, are disposed helically. In order to compensate the heat dissipation characteristics of the hot plate 51, the hot plate 5
The heat generation amount per unit area of the heater 53 ₄ is increased from the central portion of 1 to the outer peripheral portion.

As described above, in the hot plate 51, the entire upper surface 51a of the hot plate 51 is uniformly adjusted to the specified baking temperature with high accuracy by the temperature-controlled heater 53. In addition, the atmosphere around the upper surface 51a is highly accurately adjusted to the baking temperature by temperature-controlled nitrogen gas, for example.

Further, since the upper cover 61 and the lower cover 55 have the vacuum layers 63 and 57, they have excellent heat insulating properties. Further, the reflection plate 64 on the inner surface side of the upper cover 61 reflects heat. Therefore, heat radiation from the hot plate 51 and the atmosphere above the hot plate 51 through the lower cover 55 and the upper cover 61 can be extremely reduced.

From the above, in the baking tank 12, the substrate 81 placed on the upper surface 51a of the hot plate 51 can be accurately controlled to the specified baking temperature.

The substrate cooling tank 14 has a structure similar to that of the gas displacement tank 12, and is generally a hot plate 21 and a lower cover 2.
5, an upper cover 31 provided with a reflection plate 34 on the inner surface side, a cooling water circulator 42, a cooling water temperature controller 41 ₂ , a temperature sensor 43, an atmosphere temperature controller 45 ₂ , and a temperature sensor 48.

[0059] Cooling water temperature adjuster 41 _2, based on the temperature of the vicinity of the upper surface 21a of the hot plate 21 detected by the temperature sensor 43, the temperature of the cooling water circulating around the upper surface 21a of the hot plate 21 and a constant temperature The heating amount to the cooling water temperature controller 41 ₂ is controlled so that As a result, the temperature of the upper surface 21a of the hot plate 21 is adjusted to a constant temperature with high accuracy.

For example, nitrogen gas whose temperature is adjusted by the atmosphere temperature controller 45 ₂ is filled in the space surrounded by the upper cover 31 by the introduction path 47. The pressure of the nitrogen gas is set to be higher than that of the gas substitution tank 12 so that the substrate 81 after baking can be rapidly cooled to room temperature.

A plurality of temperature sensors 48 are arranged in proximity to the substrate 81 placed on the upper surface 21a of the hot plate 21, and the lead wire 49 is used to provide an atmosphere temperature controller 45 _2.
It is connected to the.

The atmosphere temperature controller 45 ₂ controls the temperature of the nitrogen gas or the like to be filled so that the temperature near the surface of the substrate 81 detected by the temperature sensor 48 becomes room temperature. As a result, the ambient temperature near the surface of the substrate 81 is cooled to room temperature.

Further, on the upper surface 21a of the hot plate 21, there is provided a groove through which the conveyor belt 19 of the conveyor 17 passes.

Next, the procedure of the baking processing of the substrate in the baking apparatus 11 will be described.

The substrate 81, which has been exposed to an electron beam using a chemically amplified resist and has not been subjected to a baking process, is housed in a delivery cassette 85. The substrate 81 is transported from the delivery cassette 85 to the inside of the gas substitution tank 12 by the transport belt 19, and then the upper surface 21 a of the hot plate 21.
Placed on.

The substrate 81 is placed on the upper surface 21 of the hot plate 21.
As a mechanism for mounting on the a, for example, as the conveyor belt 19 descends in the groove of the upper surface 21a of the hot plate 21, the substrate 81 on the conveyor belt 19 is placed on the upper surface 21a of the hot plate 21. A mounting mechanism is possible.

As described above, in the gas displacement tank 12, the atmosphere around the upper surface 21a of the hot plate 21 and the substrate 81 is adjusted to a constant temperature with high accuracy. Therefore, the temperature of the substrate 81 placed on the hot plate 21 is controlled to a constant temperature with high accuracy for a predetermined time.

In the present embodiment, there is an advantage that the temperature of the substrate 81 is unlikely to change after being controlled to a constant temperature, for example, room temperature in the gas displacement tank 12.

The substrate 81 whose temperature is controlled to a constant temperature in the gas displacement tank 12 is transferred to the baking tank 13 by the transfer belt 19 and then placed on the upper surface 51a of the hot plate 51.

In order to shorten the time for exposing the substrate 81 whose temperature is controlled to the atmosphere, the gas substitution tank 12 and the baking tank 13 are arranged as close to each other as possible. If possible, the gas replacement tank 12 and the baking tank 13 are brought into close contact with each other to form the substrate 81.
It is desirable to have a structure in which is transferred to the baking tank 13 without being exposed to the atmosphere.

The substrate 81 transferred to the baking tank 13 and placed on the upper surface 51a of the hot plate 51 is baked at a specified baking temperature (for example, 95 ° C.) for a predetermined time. By this baking, the resin is cross-linked to the exposed portion of the resist by using the acid generated during the exposure as a catalyst.

As described above, the temperature of the hot plate 51 in the baking tank 13 and the temperature of the atmosphere around the substrate 81 are
The baking temperature is controlled with high accuracy. For this reason,
It is possible to eliminate variations in the acid diffusion state within the surface of the substrate 81 and variations in the acid diffusion state between the plurality of substrates 81 due to the temperature accuracy of the baking tank 13.

Further, since the temperature of the substrate 81 is controlled to a constant temperature with high accuracy in the gas substitution tank 12, the temperature of the substrate 81 during baking can be controlled to an optimum temperature. Therefore, the acid diffusion state during baking can be optimized, and as shown in FIG. 5A, a pattern having the best dimensional accuracy can be formed.

The substrate 81, which has been baked in the baking tank 13, is transferred by the conveyor belt 19 to the substrate cooling tank 14.
Be transported to.

As described above, the atmosphere around the hot plate 21 and the substrate 81 of the substrate cooling tank 14 is controlled to a constant temperature with high accuracy. Therefore, the substrate 81 transferred to the substrate cooling tank 14 and placed on the upper surface 21 of the hot plate 21 is rapidly cooled to room temperature.

For example, cooling from the baking temperature of 95 ° C. to room temperature takes about 5 minutes in the conventional natural cooling, whereas the cooling can be performed in a short time of about 30 seconds.

As described above, since the substrate 81 can be cooled rapidly in a short time, the diffusion of acid after the baking can be suppressed to a very small extent, and the patterning of the pattern can be suppressed as compared with the natural cooling in the conventional apparatus. It is possible to improve dimensional accuracy and resolution.

The acid diffusion does not proceed on the substrate 81 which has been cooled. The substrate 81 that has been cooled is transported by the transport belt 19 and transported to the storage cassette 86 for storage.

After this, the unnecessary portion of the resist is removed by developing the substrate 81, and the pattern formation is completed.

As described above, in the present embodiment, the surface temperature of the substrate 81 can be controlled to a constant temperature with high accuracy in the gas displacement tank 12 before the baking is started. By controlling the temperature to an optimum temperature, the acid diffusion state can be optimized, and after the baking of the substrate 81 is completed, the substrate cooling tank 14 rapidly cools the substrate 81 to a constant temperature. It is possible to suppress the diffusion of acid at the time and maximize the dimensional accuracy and resolution of the pattern.

Further, when baking a large number of substrates 81, it is possible to make extremely small variations in pattern dimensional accuracy and resolution.

FIG. 3 is a side sectional view of another example of the upper cover. The upper cover 91 is the upper cover 31,
It is used instead of the upper cover 61, is formed of a partition wall 92 having a vacuum layer 93, and is provided with a reflection plate 94 on its inner surface. The reflector 94 is formed in a dome shape,
In accordance with this, the upper cover 91 is also formed in a dome shape. Since the reflection plate 94 has a dome shape, the reflected heat can be collected near the center of the upper surfaces 21a and 51a of the hot plates 21 and 51, and the ambient temperature in the space surrounded by the upper cover 91 can be made more stable. be able to.

The same effect can be obtained by using a conical shape for the reflecting plate instead of the dome shape.

[0084]

As described above, according to the invention of claim 1,
Since the heat radiation from the heat insulating cover can be extremely reduced and the temperature of the hot plate and the temperature of the atmosphere in the baking tank can be stabilized with high accuracy, the temperature of the semiconductor substrate can be controlled with high accuracy and the dimensional accuracy of the pattern, The resolution can be improved.

According to the invention of claim 4, the heater can compensate the heat dissipation characteristic of the hot plate and control the entire temperature of the hot plate to a uniform temperature. Therefore, in the semiconductor substrate mounted on the hot plate. Pattern dimensional accuracy,
The resolution can be improved.

According to the fifth aspect of the invention, since the heater temperature is controlled based on the temperatures detected by the plurality of temperature sensors provided inside the heater incorporated in the hot plate, the temperature of the hot plate can be accurately adjusted. Can be controlled.

According to the sixth aspect of the present invention, the temperature of the gas filled in the space surrounded by the heat insulating cover is controlled based on the temperatures detected by the plurality of temperature sensors provided close to the semiconductor substrate. Therefore, the temperature near the surface of the semiconductor substrate can be controlled with high accuracy.

According to the invention of claim 7, the surface temperature of the semiconductor substrate can be controlled to a constant temperature with high accuracy in the gas displacement tank before the baking in the baking tank is started. Can be set to the optimum temperature, and the dimensional accuracy and resolution of the pattern can be improved.

According to the eighth aspect of the invention, after the semiconductor substrate is baked, the surface temperature of the semiconductor substrate is rapidly cooled to a constant temperature in the substrate cooling tank, so that there is little change due to the temperature of the resist during cooling. It is possible to improve the dimensional accuracy and resolution of the pattern.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a baking apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of various examples of heaters.

FIG. 3 is a sectional view of another example of the upper cover as seen from the side surface.

FIG. 4 is an explanatory diagram of pattern formation using a chemically amplified resist.

FIG. 5 is an explanatory diagram of a relationship between a substrate temperature during baking and a formed pattern.

[Explanation of symbols]

11 Baking Device 12 Gas Displacement Tank 13 Baking Tank 14 Substrate Cooling Tank 17 Transfer Device 18 Rotating Roller 19 Conveyor Belt 21 Hot Plate 25 Lower Cover 26 Partition Wall 27 Vacuum Layer 31 Upper Cover 32 Partition Wall 33 Vacuum Layer 34 Reflector 41 ₁ , 41 ₂ Cooling water temperature controller 42 Cooling water circulator 43 Temperature sensor 45 ₁ , 45 ₂ Atmosphere temperature controller 48 Temperature sensor 51 Hot plate 53, 53 _{1 to} 53 ₄ Heater 55 Lower cover 56 Partition wall 57 Vacuum layer 61 Upper cover 62 Partition wall 63 Vacuum layer 64 Reflector 71 Heater Temperature Controller 73 Temperature Sensor 75 Atmosphere Temperature Controller 78 Temperature Sensor 81 Semiconductor Substrate 85 Delivery Cassette 86 Storage Cassette

Claims (8)

[Claims] 1. A baking apparatus in which a semiconductor substrate (81) exposed for resist patterning after resist application is placed on a hot plate (51) containing a heater (53) in a baking tank (13) for baking. A heat insulating cover (55, 61) covering the outer periphery of the hot plate (51) and the periphery of the semiconductor substrate (81) mounted on the hot plate (51) is attached to the vacuum layer (5).
7. A baking apparatus, characterized in that it is formed of partition walls (56, 62) having (7, 63) inside. 2. The baking apparatus according to claim 1, wherein the partition walls (56, 62) of the heat insulating cover (55, 61) are made of metal, ceramic or glass. 3. The baking apparatus according to claim 1, wherein at least an inner surface of the heat insulating cover (55, 61) is provided with a reflection plate (64) for reflecting heat. 4. The hot plate (51) goes from a central part of the hot plate (51) to an outer peripheral part thereof so as to compensate for non-uniformity of heat dissipation characteristics on the hot plate (51). The amount of heat generation per unit area of the heater (53) is increased.
The baking device described. 5. A plurality of temperature sensors (73) are provided inside the heater (53), and the heater (53) is controlled by a heater temperature controller (71) based on the temperature detected by each of the temperature sensors (73). 5. The baking apparatus according to claim 1 or 4, wherein the temperature of the hot plate (51) is controlled to a predetermined value. 6. A plurality of temperature sensors (78) are provided close to the semiconductor substrate (81) in a space surrounded by the heat insulating covers (55, 61), and each temperature sensor (7) is provided.
8) Atmosphere temperature controller (75) based on the detected temperature
6. The baking apparatus according to claim 5, wherein the temperature of the gas filled in the space is controlled by controlling the temperature near the surface of the semiconductor substrate (81) to a predetermined value. 7. A hot plate (21) in which cooling water whose temperature is controlled to circulate and a partition (26, 32) having a vacuum layer (27, 33) therein are formed. A heat insulating cover (25, 31) covering the outer periphery of (21) and the periphery of the semiconductor substrate (81) placed on the hot plate (21) is provided on the heat insulating cover (25, 31). A gas substitution layer (12) filled with a gas whose temperature is controlled to be constant is provided in the enclosed space, and the semiconductor substrate (8) in the baking tank (13) is provided.
The baking apparatus according to claim 1, wherein the surface temperature of the semiconductor substrate (81) is controlled to a constant temperature in the gas displacement tank (12) before the baking of 1) is started. 8. A hot plate (21) in which cooling water whose temperature is controlled to circulate and a partition (26, 32) having a vacuum layer (27, 33) therein are formed. A heat insulating cover (25, 31) covering the outer periphery of (21) and the periphery of the semiconductor substrate (81) placed on the hot plate (21) is provided on the heat insulating cover (25, 31). A substrate cooling tank filled with a gas whose temperature is controlled to be constant is provided in the enclosed space, and after the semiconductor substrate (81) is baked, the semiconductor substrate (81) is stored in the substrate cooling tank (14). 13. The baking apparatus according to claim 1 or 12, wherein the surface temperature of the is rapidly cooled to a constant temperature.