JPH1012517A - Heat treatment apparatus for substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment apparatus for substrates, capable of avoiding uneven heat treatment caused by air turbulence in a heat treatment chamber and staining of a foreign body. SOLUTION: A gas supply and exhaust body 7 is formed at an upper part of a substrate put on the plate in the upper cover 2. The gas supply and exhaust body 7 are formed by comb-shaped supply path 8a, sectioned by a partition 6b and an exhaust path 8b. The gas supplied from a gas-supplying outlet 4 flows uniformly into the comb-shaped supplying path 8a and is supplied uniformly to the surface of the substrate through the supplying outlet 10a. The gas, mixed by the supplied gas on the substrate, is sucked from the exhausting outlet 10b and exhausted from the exhausting outlet 5 through the exhausting path 8b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate heat treatment apparatus for heating or cooling a substrate.

[0002]

FIG. 6 is a front sectional view of a conventional substrate heat treatment apparatus. The substrate heat treatment apparatus includes a plate 20 on which a substrate W such as a semiconductor wafer is placed, and an upper cover 21 that covers the plate 20. Heating or cooling means such as a heater, a cooling pipe or a Peltier element is embedded in the plate 20. And the plate 20
A predetermined heat treatment is performed by heating or cooling the substrate W disposed close to the upper surface of the substrate W by heating or cooling means embedded in the plate 20.

For example, in a resist baking process, a substrate W coated with a resist is placed on a plate 20, covered with an upper cover 21, and then heated by heating means of the plate 20 to perform a baking process. When the substrate W is heated,
Excess solvent and the like in the resist on the substrate W evaporates and fills the inside of the upper cover 21. Here, if the temperature fluctuates due to the invasion of outside air from the outside, the sublimate from the resist may condense again and adhere to the surface of the resist, which is not preferable.

Therefore, a heat treatment is performed while discharging a solvent (volatile matter) or the like filling the inside of the substrate heat treatment apparatus to the outside. In the substrate heat treatment apparatus shown in FIG.
An inert gas such as nitrogen (N ₂ ) or a gas 25 such as oxygen (O ₂ ) is blown from the upper opening 22 of the upper cover 21 through the perforated plate 23 onto the surface of the substrate W, and exhaust gas provided on the plate 20 is provided. It is discharged to the outside through the port 24.

However, in the above-described substrate heat treatment apparatus, the speed of the gas flow (gas flow) becomes uneven on the surface of the substrate W. That is, the gas 25 supplied from above the upper cover 21
The flow velocity increases from the central portion of the substrate W toward the outer peripheral side. In addition, a turbulence occurs in the airflow at a portion outside the outer peripheral edge of the substrate W. Due to such non-uniform airflow velocity, non-uniform temperature distribution occurs on the resist surface of the substrate W, which causes a problem that processing unevenness occurs.

On the other hand, a method has been devised in which gas is supplied from the side of the substrate heat treatment apparatus and exhausted from above the substrate heat treatment apparatus. FIG. 7 is a sectional structural view of such a substrate heat treatment apparatus. In this substrate heat treatment apparatus, gas is supplied into the processing space 32 from an air supply port 34 provided near a boundary between the plate 30 and the upper cover 31, and exhausted from an exhaust port 33 provided at the center of the upper cover 31. It is configured as follows.

In such a configuration, the air flow is
Is supplied almost in parallel to the surface of the substrate W from outside.
The turbulence of the air flow on the surface of the substrate W is small. For this reason, the occurrence of processing unevenness due to turbulence in the airflow is suppressed.

[0008]

However, in the substrate heat treatment apparatus shown in FIG. 7, the air flow in the processing space 32 flows from the outside of the substrate W toward the center side and is lifted upward. There is a problem that foreign matter inside the apparatus is wound up on the surface of the substrate W and contaminates the substrate W.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a substrate heat treatment apparatus which does not cause processing unevenness or adherence of foreign matter due to turbulence of an air flow in a heat treatment space.

[0010]

According to a first aspect of the present invention, there is provided a substrate heat treatment apparatus, wherein an upper portion of a base is covered with an upper cover, and a heat treatment space formed between the base and the upper cover is formed. In a substrate heat treatment apparatus that performs a predetermined heat treatment while holding the substrate inside, on the lower surface of the upper cover above the substrate,
A plurality of gas outlets for supplying gas into the heat treatment space and a plurality of exhaust holes for discharging gas inside the heat treatment space are formed in a mixed manner.

A substrate heat treatment apparatus according to a second aspect of the present invention comprises:
In the configuration of the substrate heat treatment apparatus according to the invention, a gas supply passage connected to the plurality of gas outlets and an exhaust passage connected to the plurality of exhaust holes are provided inside the upper cover.

A substrate heat treatment apparatus according to a third aspect of the present invention comprises
In the configuration of the substrate heat treatment apparatus according to the present invention, the gas supply passage has an inlet into which gas is introduced and a plurality of branch passages extending from the inlet side and extending near the inside of the inlet.
A rectifying plate for dispersing and guiding gas to each of the plurality of branch paths is provided.

A substrate heat treatment apparatus according to a fourth aspect of the present invention comprises
In the configuration of the substrate heat treatment apparatus according to the present invention, the gas supply passage has an inlet into which gas is introduced and a plurality of branch passages branching from the inlet side and extending, and the exhaust passage has a plurality of gas supply passages. Has a plurality of branch passages respectively interposed in the branch passages, a plurality of gas blowing holes are arranged along each branch passage of the gas supply passage, and a plurality of exhaust holes are along each branch passage of the exhaust passage. It is what is arranged.

In the substrate heat treatment apparatus according to the first to fourth inventions, a gas is supplied into the heat treatment space from a plurality of gas blowing holes, and is uniformly mixed with a solvent or the like volatilized from the processing liquid above the substrate. You. Further, the mixed gas is quickly discharged to the outside from the plurality of exhaust holes formed in the plurality of gas blowing holes. Thereby, local convection of gas is generated over the entire surface above the substrate, and the temperature distribution in the heat treatment space can be made uniform. As a result, it is possible to prevent the occurrence of processing unevenness due to uneven temperature distribution.

In particular, in the substrate heat treatment apparatus according to the second aspect of the present invention, gas can be uniformly supplied from the plurality of gas outlets into the heat treatment space through the gas supply passage provided inside the upper cover. Further, gas containing volatile components of the processing liquid in the heat treatment space can be quickly discharged to the outside through the exhaust passage connected to the plurality of exhaust holes.

In particular, in the substrate heat treatment apparatus according to the third aspect of the present invention, a plurality of branch paths of the gas supply path are dispersed and arranged above the substrate, and a gas is evenly distributed to these branch paths using a rectifying plate. By guiding, gas can be supplied uniformly above the substrate.

In particular, in the substrate heat treatment apparatus according to the fourth aspect of the present invention, the plurality of branch paths of the exhaust passage are inserted into the plurality of branch paths of the gas supply path, so that the plurality of branch paths along the branch path of the gas supply path are provided. And a plurality of exhaust holes along the branch of the exhaust passage are alternately arranged adjacent to each other. For this reason, a local convection occurs due to the proximity of the gas blowing portion and the exhaust portion above the substrate, and the temperature distribution in the heat treatment space is made uniform, and the volatile components from the processing liquid on the substrate are made uniform. And quickly discharged outside. This prevents the occurrence of processing unevenness on the substrate.

[0018]

1 is a front sectional view of a substrate heat treatment apparatus according to a first embodiment of the present invention, FIG. 2 is a plan sectional view of the substrate heat treatment apparatus, and FIG. It is a sectional side view of a heat treatment apparatus. FIG. 1 is a view similar to FIG.
2 shows a cross section taken along the line XX in FIG. 1, and FIG. 3 shows a cross section taken along the line ZZ in FIG.

In FIG. 1 to FIG. 3, a substrate heat treatment apparatus includes a metal plate 1 having a heating or cooling means embedded therein.
And an upper cover 2 that is put on the plate 1. The upper cover 2 is formed in a lid shape having a concave portion forming the heat treatment space 3, and has a hollow structure for weight reduction. Inside the upper cover 2, there is a heat treatment space 3
A gas supply / exhaust portion 7 for supplying gas to or exhausting gas in the heat treatment space 3 (hereinafter, referred to as internal gas) is formed.

The air supply / exhaust section 7 includes a partition 6b as shown in FIG.
It has a plurality of air supply passages 8a and a plurality of exhaust passages 8b partitioned by the air passage. The plurality of air supply passages 8a and the plurality of exhaust passages 8b are formed in a comb shape, and are alternately arranged adjacent to each other. The air supply passage 8a communicates with the gas supply port 4 formed on one side surface of the upper cover 2 and the inlet space 4a surrounded by the partition 6a, and the exhaust passage 8b is formed on the other side surface. It communicates with an outlet space 5a surrounded by the exhaust port 5 and the partition 6c.

In an inlet space 4a connected to the gas supply port 4,
A plurality of flow straightening plates 9 for uniformly supplying gas to the plurality of air supply passages 8a are provided. A plurality of flow straightening plates 9 are provided corresponding to the respective air supply passages 8a, and distribute gas supplied from the gas supply ports 4 evenly to the respective air supply passages 8a.

As shown in FIG. 1, each air supply passage 8a and each exhaust passage 8b are formed by the inner wall surface 2a of the upper cover 2 and the partition 6
b and the perforated plate 11. As shown in FIG. 2, a plurality of air supply holes 10a are formed in the perforated plate 11 at positions corresponding to the air supply passages 8a, and a plurality of exhaust holes 10b are formed at positions corresponding to the exhaust passages 8b. ing. The supply holes 10a and the exhaust holes 10b are preferably arranged at a uniform pitch.

In the substrate heat treatment step using the substrate heat treatment apparatus having the above-described structure, the upper cover 2 is put on the substrate W after the substrate W is placed on the spherical spacer 1a on the plate 1. Then, a gas such as nitrogen (N ₂ ) or oxygen (O ₂ ) is supplied to the air supply passage 8a through the gas supply port 4 formed on the side surface of the upper cover 2. The gas is distributed substantially evenly into each of the comb-shaped air supply passages 8a and flows into the comb-shaped air supply passages 8a by the function of the flow straightening plate 9 disposed in the inlet space 4a. Then, the air is blown into the heat treatment space 3 through the air supply holes 10 a formed in the perforated plate 11.

On the other hand, air is exhausted from an exhaust port 5 formed on the other side surface of the upper cover 2 through an exhaust passage 8b. That is, the gas supplied from the air supply passage 8a into the heat treatment space 3 through the air inlet 10a is mixed with a processing liquid on the surface of the substrate W, for example, a solvent volatilized from the resist, and the mixed internal gas is exhausted. The gas is discharged from the hole 10b to the outside through the exhaust port 5 through the exhaust passage 8b.

In the above substrate heat treatment apparatus, the substrate W
A plurality of air supply holes 8a are evenly arranged on the surface of.
For this reason, the gas supplied from the plurality of gas supply holes 8a is mixed with the internal gas in the heat treatment space 3 around each gas supply hole 10a. For this reason, on the surface of the substrate W, the internal gas is almost uniformly mixed over the entire surface, and the concentration of volatile components from the processing liquid contained in the internal gas is made uniform. Further, the plurality of exhaust holes 10b are also arranged uniformly on the surface of the substrate W. Therefore, the internal gas uniformly mixed on the surface of the substrate W can be quickly discharged through the plurality of exhaust holes 10b.

As described above, on the surface of the substrate W, local convection occurs around each of the air supply holes 10a and each of the exhaust holes 10b, and the flow state of the air flow becomes uniform, so that the heat treatment is performed uniformly. In addition, the occurrence of processing unevenness is prevented.

It is preferable that the supply amount of gas in the heat treatment space 3 and the exhaust amount of the internal gas are substantially equal or the exhaust amount is slightly reduced in order to keep the inside of the heat treatment space 3 clean.

FIG. 4 is a front sectional view of a substrate heat treatment apparatus according to a second embodiment of the present invention. The substrate heat treatment apparatus shown in FIG. 4 differs from the substrate heat treatment apparatus shown in FIGS. 1 to 3 in the configuration of the gas supply path to the supply / exhaust section 7 and the internal gas discharge path. That is, plate 1 has
Gas supply path 15 for supplying gas to upper cover 2 and exhaust path 18 for discharging internal gas in heat treatment space 3
Are formed. Gas supply path 15 and exhaust path 18
Open through the plate 1 to the upper surface of the plate 1.

In the upper cover 2, a gas introduction path 16 is formed at a position corresponding to the gas supply path 15. An exhaust path 17 is formed at a position corresponding to the exhaust path 18. Although not shown, the gas introduction path 16 and the exhaust path 17 close the gas introduction path 16 and the lead-out path 17 when the upper cover 2 is separated from the plate 1, and the upper cover 2 Gas introduction path 16
And an opening / closing member that opens the exhaust path 17 and communicates with the gas supply path 15 and the exhaust path 18 of the plate 1, respectively.

One end of the gas introduction passage 16 communicates with the air supply passage 8 a of the air supply / exhaust unit 7, and the gas supply passage 15
The gas supplied through is supplied to the air supply passage 8 a of the air supply / exhaust unit 7. One end of the lead-out passage 17 communicates with the exhaust passage 8b of the supply / exhaust unit 7. Then, the internal gas discharged from the inside of the heat treatment space 3 through the exhaust passage 8 b is exhausted to the outside through the exhaust passage 18 of the plate 1.

In this embodiment, the structure of the air supply / exhaust section 7 is the same as that of the first embodiment. Accordingly, the gas can be uniformly supplied into the heat treatment space 3, and the volatile components from the processing liquid can be uniformly mixed on the surface of the substrate W and quickly discharged to the outside.

FIG. 5A is a partial plan sectional view of the upper cover 2 using another rectifying plate different from the rectifying plate shown in FIG. 2, and FIG. 5B is a plan view of the rectifying plate. is there. FIG.
The baffle plate 12 shown in (b) has a plurality of holes 13 formed on the surface of the long plate-shaped member to allow airflow to pass therethrough. The current plate 12 is disposed along the direction from the gas supply port 4 to the outside air supply passage 8 a, and the gas supplied from the gas supply port 4 is supplied to the outside gas supply passage 8 a along the current plate 12. And acts to evenly supply gas to each air supply passage 8a through the hole 13 of the current plate 12.

The rectifying plate 9 shown in FIG.
In addition to the current plate 12 shown in FIG. 5, another current plate may be used. Further, the mounting direction may be movable.

The air supply / exhaust portion 7 in the first and second embodiments is constructed by combining a comb-shaped air supply passage 8a and a gas exhaust passage 8b with each other. The shape of the exhaust passage 8b is not limited to this. That is, in the present invention, the air supply holes 10a for supplying gas onto the surface of the substrate W and the exhaust holes 10b for discharging the internal gas to the outside may be arranged evenly close to each other. Therefore, for example, the air supply passages 8a and the exhaust passages 8b may be alternately arranged in a spiral shape.

Further, the substrate heat treatment apparatus to which the air supply / exhaust section 7 of this embodiment is applicable includes not only a so-called hot plate but also a cooling plate.

[Brief description of the drawings]

FIG. 1 is a front sectional view (a sectional view taken along line YY in FIG. 2) of a substrate heat treatment apparatus according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX in FIG.

FIG. 3 is a sectional view taken along line ZZ in FIG. 2;

FIG. 4 is a front sectional view of a substrate heat treatment apparatus according to a second embodiment of the present invention.

5A is a partial plan cross-sectional view of a substrate heat treatment apparatus using another example of a current plate, and FIG. 5B is a plan view of the current plate.

FIG. 6 is a front sectional view of a conventional substrate heat treatment apparatus.

FIG. 7 is a front sectional view of another conventional substrate heat treatment apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate 2 Upper cover 3 Heat treatment space 4 Gas supply port 5 Exhaust port 6a, 6b Partition wall 7 Supply / exhaust part 8a Supply path 8b Exhaust path 9, 12 Rectifier plate 10a Supply hole 10b Exhaust hole 11 Perforated plate 15 Gas supply path 16 Gas Introductory route 17 Outgoing route

Claims (4)

[Claims] 1. A substrate heat treatment apparatus, wherein an upper portion of a base is covered with an upper cover, and a predetermined heat treatment is performed by holding a substrate in a heat treatment space formed between the base and the upper cover. On the lower surface of the upper cover above the substrate, a plurality of gas blowing holes for supplying gas into the heat treatment space, and a plurality of exhaust holes for discharging gas inside the heat treatment space are mixed. A substrate heat treatment apparatus characterized by being formed by: 2. The substrate heat treatment according to claim 1, wherein a gas supply passage connected to the plurality of gas blowing holes and an exhaust passage connected to the plurality of exhaust holes are provided inside the upper cover. apparatus. 3. The gas supply passage has an inlet through which the gas is introduced, and a plurality of branch passages that branch off from the inlet side and extend near the inside of the inlet. 3. The substrate heat treatment apparatus according to claim 2, wherein a rectifying plate for dispersing and guiding gas is disposed in each of the branch paths. 4. The gas supply passage has an inlet through which the gas is introduced, and a plurality of branch passages branching from the inlet side and extending, and the exhaust passage includes a plurality of the gas supply passages. A plurality of branch passages respectively interposed between the branch passages, the plurality of gas blowing holes are arranged along each branch passage of the gas supply passage, and the plurality of exhaust holes are each of the exhaust passages. The substrate heat treatment apparatus according to claim 2, wherein the substrate heat treatment apparatus is arranged along a branch path.