JPS607959A - Rotary coater - Google Patents

Abstract

PURPOSE:To prevent generation of turbulent flow and to eliminate uneven coating, etc. by forming an air discharge line and a liquid discharge line into throughly separate lines and controlling the atmosphere in a chamber. CONSTITUTION:An air feed port 33 and an air feed pipe 34 are provided in the upper part of a cover 31 provided to a rotary coater. An air discharge port 35 is disposed on the side wall of a cup 32 and a wall surface 37 opened with many holes 37h is disposed on the inside of a cover receiving part 38 in front thereof. A ring 39 for preventing splash is provided to enclose the port 35 by contacting with the bottom of the wall surface 37. A drain 36 is provided to the bottom of the cup 32 separately from the port 35. The atmosphere in a chamber 30 is then controlled and turbulence, uneven coating, etc. are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (11) Technical Field of the Invention The present invention relates to a spin coating apparatus, and more particularly, to a structure of a spin coating apparatus in which the atmosphere within a coating chamber can be controlled.

(2) Background of the Technology A spin coating device is used for the purpose of, for example, applying a resist solvent f onto a wafer, and then applying the solvent to the entire surface of the wafer using the centrifugal force generated by rotating the wafer at high speed.

FIG. 1 is a sectional view showing the structure of a conventional spin coating device. Referring to the figure, the coating chamber 1 of the device is
and a cup 3 with a splash prevention ring 8 arranged on the side.
Inside the cup 3, there is provided a chuck 7 that holds a sample (plate to be coated) 5 such as a wafer and rotates at high speed.
An exhaust port 6 that also serves as a drain is provided. On the other hand, a nozzle 4 for dropping a coating liquid onto the wafer 5 is arranged on the cover 2 .

Fig. 2 is a sectional view showing the structure of another spin coating device.
Referring to the figure, the chamber 21 of the device has a double cup structure consisting of cups 22 and 23, the inner cup 23 is provided with a drain 25, and the outer cup 22 is provided with an exhaust port 26. These 1″ rain 2
5 and the exhaust port 26 have a double structure like the cup.

On the other hand, a chuck 7 for holding and rotating the wafer 5 is provided in the chamber 2, as in FIG. 1, and a nozzle 24 is disposed above the chuck 7.

In either of the two rotary coating apparatuses described above, the cup can move in the direction (up and down) shown by arrow a in FIG. After mounting, the scoop moves upward and returns to the position shown in the figure.

After the wafer is mounted in this way, the coating solvent is dripped onto the wafer from the nozzle, and then the chuck is rotated at high speed by a drive device (not shown) to perform coating. Furthermore, in some apparatuses, the nozzle is rotatable to prevent the solvent from dripping during rotation, and the nozzle is moved to a position other than above the wafer during coating.

By the way, as the wafer rotates at high speed in the rotary coating device, most of the dripped solvent scatters into the chamber, and the scattered solvent becomes mist in the air.
This may come out of the chamber and cause environmental contamination, or it may adhere to the inner wall of the chamber or directly re-adhere to the wafer. Therefore, it is necessary to ensure that the spattered solvent is discharged from the drain.

(3) Prior Art and Problems Conventionally, the coating solvent in the apparatus having the structure shown in FIG. The solvent 11 is left in the tank 10, and the external air is exhausted from another pipe 13 through an exhaust duct installed in a factory, for example.

However, in this method, since the exhaust port 6 also serves as a drain, the coating solvent in the cup 3 and the drain tank 10 evaporates rapidly, and as a result, the solvent tends to solidify, making recovery difficult.

In addition, in the structure of the device, since the chamber is sealed by the cover 2, turbulence occurs around the wafer 5.
There is a problem in that the spattered solvent is not quickly discharged from the drain and adheres to the wafer 5 and the like.

On the other hand, the spin coating device shown in FIG. 2 has a structure in which the exhaust port 26 and the drain 25 are arranged separately, and it is possible to prevent the solvent from solidifying due to the exhaust flow.
6 and the drain 25 have a double structure and a double structure (1).Also, the problem of turbulence occurring inside the chamber 2 because no air supply port is provided has also been resolved. Not yet.

(4) Purpose of the Invention In view of the above-mentioned conventional problems, the present invention provides a system in which the exhaust system and the liquid drainage system are completely separate systems, the atmosphere inside the gas chamber is controlled, and the rotational coating is capable of preventing the occurrence of turbulence. The purpose is to provide equipment.

(5) Structure and object of the invention According to the present invention, an apparatus is provided for applying a solvent to a sample by spin coating, an air supply port is provided in the cover, and an exhaust port is provided as a separate system from the drain. This is achieved by providing a rotary coating device characterized in that the air supply port and the exhaust port are both provided in the cover, and the shape of the air supply port is made to have the same spread as the sample. This can also be achieved by forming a hole with holes, by connecting an air supply pipe to the air supply port, or by arranging a wall surface with many holes in front of the exhaust port.

(6) Examples of the invention Embodiments of the present invention will be explained in detail below with reference to the drawings.

FIG. 3 is a sectional view showing the structure of a spin coating device for explaining the first embodiment of the present invention. Referring to the figure, an air supply port 23 and an air supply pipe 34 are provided in the upper part of the cover 31. ,
On the other hand, an exhaust port 35 is provided on the side wall of the cup 32;
There are many holes 37h inside the cover holder part 38 at the front of 5.
A wall surface 37 with a gap is provided, and a spring burr prevention ring 39 is attached to the bottom of the wall surface 37 to surround the exhaust port 35.
will be established. Further, a drain 36 is provided at the bottom of the cup 32 separately from the exhaust port 35.

In the above structure, the size of the air supply port 23 is, for example, a circular hole with the same size as the wafer 5.
If the object to be coated (object to be coated) has a shape other than the wafer, an air supply port having an arbitrary shape with the same extent is provided as appropriate.

Further, the exhaust port 35 is connected to a duct of an exhaust system (not shown) via piping, and the drain 46 is connected to a train tank (not shown) by piping. Further, for the wall surface 37 with holes arranged in front of the exhaust port 35, a net-like plate or a punching board (a board with holes punched out) or the like can be used. In the figure, reference numeral 4 indicates a nozzle, and reference numeral 7 indicates a chuck.

” Since it has a double-connected configuration, the air supply I passes through the air supply pipe 34.
33 into the chamber 30 becomes a uniform downward airflow from the air supply port 33 toward the perforated wall surface 37, as shown by the solid line, so that turbulence is prevented from occurring.

Then, the gas passes through the perforated wall surface 37 and is exhausted from the exhaust port 35, while the mist is prevented from scattering upward by the anti-splash ring 39, and is prevented from entering the exhaust port 35 by the wall surface 37, so that the above-mentioned downward air flow Therefore, it is quickly discharged from the drain 36 without re-adhering to the wafer. In this way, the conventional problems are solved, the coating solvent is easily recovered, and the precision of the coating process is improved.

FIG. 4 is a cross-sectional view showing the structure of a rotary coating device according to a second embodiment of the present invention. Referring to the same figure, a cover 43 has a flat plate structure with an air supply port 42 provided in the center, and the other cup 4
1 has an exhaust port 45 on the side and a drain 36 on the bottom.
In front of the exhaust port 45, there is a splash prevention ring 47 and a wall surface 4 with a hole surrounding it.
4 will be placed. Note that for the wall surface 44, a punching board or a net-like board can be used as in the first embodiment. Further, the size and shape of the air supply port 42 are appropriately selected in the same manner as in the first embodiment, and the exhaust port 45 and drain 46 are connected to an exhaust duct or a drain tank (not shown) via piping.

In this structure, the air supply is a natural air supply method in which the air is directly taken in from the outside of the device, and the gas taken in is from the wafer 5.
The air flows uniformly downward toward the air and is exhausted from the exhaust port 45. Note that the nozzle is omitted in the figure.

FIG. 5 is a sectional view showing the structure of a spin coating device for explaining a third embodiment of the present invention. Referring to the figure, the device includes an air supply cover 51 forming an air supply port 52 and an exhaust port. 54
The cover is made up of two exhaust covers 53 provided with a
The structure is such that only the drain 56 at the bottom is provided.

Furthermore, the fourth and fifth embodiments of the present invention shown in FIGS. 6 and 7
In this embodiment, the air supply port and the exhaust port are provided in the cover as in the third embodiment, but the cover is not composed of two parts as in the device shown in FIG. 5, but is constructed as an integral structure. shall be. In the apparatus shown in FIG. 7, the nozzle 4 is covered with a cover 7.
1 to facilitate the driving of the nozzle 4, and unlike the device shown in FIG. 6, the exhaust lower 3 is provided above the cover 71.

In addition, in FIGS. 6 and 7, 61.71 is a cover, 62.72 is an air supply port, 63.73 is an exhaust port, and 65.7 is a cover.
5 is the cover, 67.77 is the anti-splash ring, 66
．． 76 indicates a drain. Also, solid arrows indicate the flow of the feed gas and the flow of the solvent.

In addition, in the structures shown in FIGS. 5 to 7, the spring prevention ring prevents mist from entering the exhaust port, and the size and shape of the air supply port are the same as in the first or second embodiment. Select as appropriate.

FIG. 8 is a cross-sectional view showing the structure of a spin coating device showing a sixth embodiment of the present invention. Referring to the same figure, a cover 89 is composed of an air supply cover 81 and an exhaust cover 83, and the air supply cover An air supply pipe) 38 is connected to the supply port 82 of the exhaust cover 81, and an exhaust pipe (not shown) is connected to the exhaust port 84 of the exhaust cover 83, so that the chamber 80 has a sealed structure. The structure includes a sagging prevention ring 87 and a drain 86 at the bottom.

With this structure, the atmosphere inside the chamber 80 can be controlled. For example, if air or nitrogen gas (N2) containing a coating solvent is supplied into the chamber, evaporation of the solvent can be suppressed and uneven coating can be prevented.

By the way, in any of the above-described embodiments of the present invention, if it is desired to make the nozzle movable, this purpose can be easily achieved by providing a notch in the reciprocating part of the nozzle, and if the nozzle driving part is housed in the cover, the device can be moved easily. can be downsized. In the case of the fifth embodiment of the present invention shown in FIG. 7, the nozzle drive section can be attached to the upper part of the exhaust cover 71.

(7) Effects of the Invention As explained in detail above, according to the present invention, by separately providing exhaust and drainage means in the rotary coating device, recovery of the coating solvent is facilitated, and the air supply port provided in the cover This allows for a more uniform downdraft,
Furthermore, since the atmosphere inside the chamber can be controlled, the operation of the apparatus is facilitated and uneven coating is eliminated, which is highly effective in improving yields in semiconductor device manufacturing.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 are sectional views showing the structure of a conventional spin coating device, and FIGS. 3 to 8 are sectional views of a spin coating device according to an embodiment of the present invention. 1, 21.30.80---chamber, 2.31,4
3,61.71--one cover, 3.22,23,32,
41,57,65,75.85--One cut, 4-nozzle, 5-wafer, 6-exhaust port and drain, 7-chuck, io-train tank, 26, 36, 46, 56, 6
6.76.86- Drain, 25.35, 45, 54
,63,73.84-exhaust port,33.42,52,62
, 72.82-Air supply port, 37, 44-11-sized open wall, 8.39, 47, 55, 67.77.87--Spring release prevention ring, 51.81-Air supply cover, 53 , 83-...Exhaust cover Fig. 1 Fig. 2 Fig. 5 Fig. 8

Claims (1)

[Claims] (A device for applying a solvent to a sample by 11 rotations, characterized by having an air supply port in the cover and an exhaust port as a separate system from the train. (2) The rotary coating device according to claim 1, characterized in that both the air supply port and the exhaust port are provided in a cover. (3) The air supply port has a shape that is Claim 1, characterized in that the hole has the same extent as the sample.
The spin coating device according to item 1 or 2. (4) The spin coating device according to claim 1 or 2, characterized in that an air supply pipe is connected to the air supply port. (5) The spin coating device according to claim 1, 2, or 3, characterized in that a wall surface with a large number of holes is provided in front of the exhaust port.