JP4224235B2 - Substrate dryer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate drying apparatus that forms a functional thin film by heating and drying a solution applied to an upper surface of a substrate.
[0002]
[Prior art]
For example, in a manufacturing process of a semiconductor device, a liquid crystal display device, and the like, there are a film forming process and a photo process for forming a circuit pattern on a semiconductor wafer as a substrate or a glass substrate for liquid crystal. In these processes, functional thin films such as alignment films, resists, color filters, and organic electroluminescence are formed on the upper surface of the substrate.
[0003]
When a functional thin film is formed on the upper surface of a substrate, the solution on the upper surface of the substrate may be dried by applying the solution to the upper surface of the substrate and heating the substrate with a hot plate. When the substrate is heated by a hot plate, a plurality of support pins are provided on the upper surface of the hot plate in order to make the heating uniform, and the substrate is supported by these support pins.
[0004]
[Problems to be solved by the invention]
However, when the lower surface of the substrate is supported by the support pins, the heat from the hot plate is easily transmitted to the portion supported by the support pins. Therefore, a difference occurs in the drying speed between the portion supported by the support pins of the substrate and the portion not supported, and as a result, the film thickness formed on the upper surface of the substrate may not be uniform.
[0005]
It is an object of the present invention to provide a substrate drying apparatus capable of forming a functional thin film having a substantially uniform thickness without unevenness on the upper surface of a substrate.
[0006]
[Means for Solving the Problems]
The invention of claim 1 is a substrate drying apparatus for forming a functional thin film by heating and drying a solution applied to an upper surface of a substrate.
A hot plate,
A support means provided on the upper surface of the hot plate and supporting a plurality of locations on the lower surface of the substrate heated by the hot plate;
Provided on the upper surface side of the substrate, the gas supplied toward the upper surface of the substrate from above the substrate to flow in the same direction along the upper surface of the substrate, the flow direction of the gas of said substrate Rectifying means for inclining with respect to the upper surface;
It is characterized by comprising.
[0008]
According to this invention, the unevenness of the solution generated on the upper surface of the substrate can be smoothed by the gas flow from the rectifying means, and a functional thin film having a substantially uniform thickness is formed on the upper surface of the substrate without unevenness. be able to.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 show a first reference example of the present invention. The substrate drying apparatus shown in FIG. The apparatus body 1 includes a rectangular plate-shaped base plate 2 and a distribution member 3 provided on the upper surface of the base plate 2 and having substantially the same shape as the base plate 2.
[0011]
A substantially rectangular recess 4 is formed on the lower surface of the distribution member 3, and a space 6 is formed between the distribution plate 3 and the base plate 2. The distribution member 3 has a plurality of ventilation holes 5 that communicate the recess 4 with the upper surface of the distribution member 3.
[0012]
A support frame member 7 as a support means is provided on the peripheral edge of the upper surface of the distribution member 3 over the entire circumference. The support frame member 7 is formed on an inclined surface 7a whose upper end is lowered inward, and the peripheral edge of the substrate W is engaged with the inclined surface 7a so that the substrate W can be supported horizontally. It has become.
[0013]
A plurality of emergency support pins 7A are erected on the upper surface of the distribution member 3 and inside the support frame member 7, and the substrate W supported by the support frame member 7 is greatly bent. In some cases, the lower surface can be supported.
[0014]
Hot air is supplied to the space 6 by hot air supply means 8. The hot air supply means 8 is provided in a supply pipe 9 having one end connected to the substantially central portion of the base plate 2, a blower 10 connected to the other end of the supply pipe 9, and a middle portion of the supply pipe 9. And a heater 11 for heating the air blown from the blower 10. Accordingly, hot air heated to a predetermined temperature can be supplied to the space 6. The hot air supplied to the space 6 flows almost uniformly into the lower surface side of the substrate W supported by the support frame member 7 through the ventilation holes 5 of the distribution member 3.
[0015]
The support frame member 7 is provided with discharge means 12. The discharge means 12 has a discharge port 13 formed at a predetermined position of the support frame member 7, for example, in the middle of each side of the support frame member 7, and each of the discharge ports 13 has a discharge pipe. 14 is connected. These discharge pipes 14 are connected to a suction pump 15, and by operating the suction pump 15, a gas at a predetermined temperature supplied from the hot air supply means 8 and flowing into the lower surface side of the substrate W is supplied to the lower surface side of the substrate W. Can be discharged from. The discharge means 12 may be configured such that the discharge port 13 is only formed in the support frame member 7 and is not forcibly discharged by the suction pump 15.
[0016]
The operation when using the substrate drying apparatus having the above configuration will be described.
[0017]
If the substrate W coated with the solution for forming the functional thin film on the upper surface is horizontally supported on the inclined surface 7a of the support frame member 7, a predetermined temperature, for example, 120 to 150 degrees, is supplied from the supply pipe 9 to the space portion 6. Supply hot air heated to a certain degree. The hot air supplied to the space 6 flows into the lower surface side of the substrate W supported by the support frame member 7 through the ventilation holes 5 and then is discharged from the discharge port 13 by the suction pump 15. Therefore, since the substrate W is heated almost uniformly by the gas flowing on the lower surface side thereof, the solution applied to the upper surface of the substrate W is also heated and dried almost uniformly through the substrate W to form a functional thin film. become.
[0018]
Thus, since the gas heated to the predetermined temperature is supplied to the lower surface side of the substrate W, the entire plate surface of the substrate W can be uniformly heated. Therefore, since the solution applied to the upper surface of the substrate W can be heated uniformly, a functional thin film having a uniform thickness can be formed on the upper surface of the substrate W. Furthermore, since hot air is supplied from the lower surface of the substrate W, it is possible to reduce the bending of the substrate W due to its own weight due to the pressure of the hot air.
[0019]
Since the periphery of the substrate W is supported by the inclined surface 7a of the support frame member 7, the temperature of the periphery may be higher than that of other portions. However, since the solution is usually applied to the upper surface of the substrate W except for the peripheral portion, even if the peripheral portion of the substrate W is easily supported by the support frame member 7, There is no possibility that the thickness of the functional thin film formed on the upper surface of the substrate W becomes non-uniform.
[0020]
FIG. 3 shows a second reference example of the present invention.
[0021]
In the first reference example, the entire outer peripheral edge of the substrate W is supported by the support frame member 7, but in the second reference example , as shown in FIG. 3, for example, support members are provided at the four corners of the apparatus main body 1. 16 are provided to support the four corners of the substrate W.
In this case, since the opening 17 is formed between the support members 16 on each side of the upper surface of the apparatus body 1, the gas supplied to the lower surface of the substrate W is naturally discharged from the opening 17. It will be. Therefore, the discharge means 12 for discharging the supplied to the upper surface of the apparatus main body 1 gas is also formed only by the opening 17. That is, as the discharge means 12, the suction pump 15 and the discharge pipe 14 shown in the first reference example may not be used.
[0022]
FIG. 4 shows a third reference example of the present invention.
[0023]
This third reference example is a modification of the hot air supply means 8, and as shown in FIG. 4, a heater 18 is provided in the space 6, and the normal temperature supplied from the supply pipe 9 to the space 6 is maintained. The gas is heated by the heater 18. Thereby, a gas having a predetermined temperature can be supplied to the lower surface side of the substrate W.
[0024]
Figure 5 shows an embodiment of the present invention.
[0025]
The substrate drying apparatus shown in FIG. 5 is provided in a clean room (not shown). A downflow indicated by an arrow in the figure is generated in the clean room.
[0026]
The substrate drying apparatus has a hot plate 20. A control device (not shown) is connected to the hot plate 20, and the upper surface of the hot plate 20 can be heated to a predetermined temperature by operating the control device.
[0027]
A plurality of support pins 21 as support means are provided on the upper surface of the hot plate 20, and the lower surface of the substrate W supported on the upper ends of the support pins 21 is heated by heating the hot plate 20. It can be done. The support pin 21 is made of a material having a predetermined thermal conductivity.
[0028]
A filter 22 such as a HEPA filter is provided above the substrate W. The filter 22 filters the gas blown down toward the upper surface of the substrate W by the downflow, and prevents particles contained in the gas from adhering to the upper surface of the substrate W.
[0029]
Between the filter 22 and the substrate W, a plurality of rectifying plates 23 serving as rectifying means are arranged in parallel so that the longitudinal direction is along the entire length in the width direction of the substrate W. Each rectifying plate 23 is inclined at a predetermined angle θ, for example, approximately 45 degrees with respect to the plate surface of the substrate W supported by the support pins 21, and the gas that passes through the filter 22 and is blown down substantially vertically is transferred to the substrate. Inclined to W and supplied.
[0030]
Next, an operation when the substrate drying apparatus having the above-described configuration is used will be described.
[0031]
When the substrate drying apparatus having the above configuration is used, a downflow is generated in advance in the clean room. The gas blown down toward the upper surface of the substrate W by this downflow is filtered by the filter 22 and fine particles such as particles are removed.
[0032]
The gas that has passed through the filter 22 is supplied to the upper surface of the substrate W at an angle of approximately 45 degrees with respect to the substrate W by the rectifying plate 23. When the inclined gas reaches the substrate W, it flows along the inclined direction on the upper surface, and the solution applied to the upper surface of the substrate W is dried.
[0033]
On the other hand, the substrate W coated with the solution for forming the functional thin film on the upper surface is heated to a predetermined temperature by the hot plate 20.
[0034]
Part of the heat from the hot plate 20 is supplied to almost the entire substrate W through the gas on the upper surface side of the hot plate 20. Thereby, the solution applied to the upper surface of the substrate W is heated.
[0035]
A part of the heat from the hot plate 20 is also transmitted to the substrate W from the support pins 21 provided on the upper surface of the hot plate 20. Therefore, the temperature of the portion of the substrate W supported by the support pins 21 is higher than that of the unsupported portion, so that a temperature difference occurs in the solution applied to the upper surface of the substrate W. That is, the portion of the substrate W that is supported by the support pins 21 has a higher temperature than the portion that is not supported.
[0036]
In general, a liquid has a property of flowing from a high temperature portion to a low temperature portion. Therefore, the solution coated on the substrate W to flow toward the lower temperature portion of the periphery thereof from the portion becomes higher temperature is supported by the support pins 21. Thereby, the solution applied to the upper surface of the substrate W becomes uneven in the heating process.
[0037]
However, in the present invention, the gas is supplied from above the substrate W at a predetermined angle so as to flow along the upper surface by the rectifying plate 23. Therefore, the unevenness of the solution generated on the upper surface of the substrate W in the heating step is smoothed by the gas flow from each of the rectifying plates 23, so that the upper surface of the substrate W has a function with a substantially uniform thickness. A conductive thin film is formed.
[0038]
That is, by flowing the gas along the upper surface of the substrate W, the solution applied to the upper surface of the substrate W is forcibly smoothed, so that a functional thin film having a uniform thickness can be formed. Further, since the gas is supplied from above the substrate W via the rectifying plate 23, even if the substrate W is enlarged, a substantially uniform air flow can be supplied to the entire plate surface of the substrate W. Therefore, even when the substrate W is enlarged, a functional thin film having a uniform thickness can be formed.
[0039]
In the fourth embodiment, the airflow in a predetermined direction is supplied by the rectifying plate 23 using the downflow of the clean room. However, when there is no downflow, the gas is supplied by a blower or the like. May be.
[0040]
【The invention's effect】
According to the present invention, it is possible to form a functional thin film having a substantially uniform thickness without unevenness on the upper surface of the substrate.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a substrate drying apparatus according to a first reference example .
FIG. 2 is a plan view showing a substrate drying apparatus according to a first reference example .
FIG. 3 is a plan view showing support means of a second reference example .
FIG. 4 is a cross-sectional view showing hot air supply means of a third reference example .
FIG. 5 is a front view showing a substrate drying apparatus according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 20 ... Hot plate, 21 ... Support means (support pin), 23 ... Rectification means (rectification plate), W ... Board | substrate.

Claims (2)

In a substrate drying apparatus that forms a functional thin film by heating and drying the solution applied to the upper surface of the substrate,
A hot plate,
A support means provided on the upper surface of the hot plate and supporting a plurality of locations on the lower surface of the substrate heated by the hot plate;
Provided on the upper surface side of the substrate, the gas supplied toward the upper surface of the substrate from above the substrate to flow in the same direction along the upper surface of the substrate, the flow direction of the gas of said substrate Rectifying means for inclining relative to the upper surface;
A substrate drying apparatus comprising: 2. The rectifying device according to claim 1, wherein the rectifying means includes a plurality of rectifying plates arranged in parallel with each other at intervals, and the rectifying plates have a longitudinal direction along the entire length in the width direction of the substrate. A substrate drying apparatus, wherein the substrate drying device is inclined with respect to the substrate supported by the supporting means.

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