JPS62176572A - Apparatus for forming film - Google Patents

Abstract

PURPOSE:To contrive to enhance the quality of a film by uniformizing the thickness of the film and eliminating air bubbles, by applying static pressure to the film applied to a surface to be coated. CONSTITUTION:A plate 1 to be coated is placed on the sucking surface 2a of the vacuum chuck 8 in a hermetically sealed space 6 and a film is formed to the plate 1 to be coated while the chuck 8 is rotated and a coating solution 4 is dripped. Because air bubbles are contained in the film and the thickness of the film has irregularity in this stage, after the dripping of the coating solu tion 4 is finished, the rotation of the vacuum chuck 8 is stopped and a pressuriz ing part 7 is started to raise the internal pressure of the hermetically sealed space 6, for example, to 10atm. By this method, because static pressure is applied to the film and isotropic pressure is acted on the entire surface of the film, not only air bubbles present in a foam state are collapsed and eliminat ed but also the thickness of the film is also uniformized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a coating film forming apparatus for depositing a resist coating onto a semiconductor wafer in, for example, an LSI manufacturing process.

[Technical background of the invention and its problems]

In general, in the LSI manufacturing process, photosensitive and
Corrosion Resistance G There is a process of applying a resist made of IJ material onto the wafer. Conventionally, a dedicated coating film forming apparatus such as a spinner or a roller coater is used in this resist coating process.

However, each of the conventional coating film forming apparatuses has its own drawbacks, and it has been extremely difficult to stably obtain a high quality coating film over a long period of time. For example, in the case of a spinner, the shape of the surface to be coated is rectangular.
It is difficult to obtain a coating film of uniform thickness when the coating is not rotationally symmetrical or when there are irregularities on the surface to be coated. In addition, in the case of a roller coater, air bubbles may get into the applied coating, and these air bubbles may cause defective products.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coating film forming apparatus that can easily and uniformly apply a coating film to a surface to be coated. Required] A coating film forming device that forms a coating film on a surface to be coated by supplying a coating agent to the surface to be coated while rotating an object having a surface to be coated around a rotational axis substantially perpendicular to the surface to be coated. In this method, static pressure is applied to the formed coating film using pressurized gas.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

The figure shows the coating film forming apparatus of this example.

This device is used to coat substrates such as semiconductor wafers (
A holding part (2) that removably holds 1) by vacuum suction and drives it to rotate at high speed; A sealing part (3), a coating agent supplying part (5) that drips a liquid film agent (4) onto the plate to be coated (1) held in the holding part (2), and a bending/sealing part ( 3), and a pressurizing section (7) that applies static pressure to the plate to be coated (1) by processing the sealed space (6) formed by 3) to a pressure higher than atmospheric pressure. Therefore, the holding part (2) is attached to the suction surface (2a) of the plate to be coated (1).
) and vacuum chuck (8) that removably vacuum-chucks the plate to be coated (1) through a suction hole (not shown) opened in the suction surface (2a); A rotating shaft (9) coaxially connected to the lower end surface of the chuck 18) is connected to the lower end side of the rotating shaft (9), and the rotating shaft (9) is
9) for example, a drive mechanism (
(not shown) and a vacuum source (not shown) fluidly connected to the suction hole of the vacuum chuck (8).

Furthermore, the sealed portion (3) is composed of a hollow cylindrical main body αυ that forms a sealed space (6), and a door (not shown) that is anchored to the main body αυ so as to be openable and closable. The above body αυ
A vacuum chuck (8) is housed in the housing, and a rotating shaft (9) is inserted through the shaft in a sealed state. Further, the coating agent supply section (5) is attached to the upper end of the main body, and the coating agent (4) is supplied to the plate (1) to be coated while the coating agent (4) is being rotated at the same time.
), and a storage liquid 41v (not shown) that supplies the coating agent (4) τ to the dropping device α2. And the above-mentioned dropping device (12 is a rotating shaft (9)
A cylindrical liquid supply a3 that is fixed to the main body αB and protrudes into the sealed space (6) almost coaxially with the liquid supply α3, a nozzle α fathom protruding from the lower end of the liquid supply α3, and a nozzle α
It consists of a dripping control section (not shown) that controls the dripping of the coating material (4) from the core. Furthermore, the pressurizing part (7)
An air supply pipe (1!9) whose one end is connected to the main body αB at two symmetrical places and communicates with the sealed space (6), and this air supply pipe u
The other end of 9 is connected to the air supply pipe (through one to the sealed space (
It consists of compressed air i11!QB, which is the standard way to use compressed air.

Next, the operation of the coating film forming apparatus having the above configuration will be described.

First, the door of the sealed part (3) is opened and the plate to be coated (1) is placed on the suction surface (2a) of the vacuum chuck (8). Then, the door is closed to seal the inside of the sealed space (6).

Next, the drive mechanism rotates the rotation shaft (9) and the vacuum chuck (8) in the direction of the arrow OQ at, for example, 1,000 revolutions per minute, and the liquid coating agent (4) is applied from the nozzle I of the dropping device mua. Plate to be coated rotating at high speed (1)
Drip on top. Then, the coating agent (4) is applied to the plate to be coated (1
1, a coating film +171 shown in FIG. 2 is formed.

However, at this stage, the coating film αη contains air bubbles, and there are variations in the film thickness.

Therefore, after finishing dropping the coating agent (4), the vacuum chuck (8)
After stopping the rotation, the pressurizing section (force) is activated to raise the internal pressure of the sealed space (6) to, for example, 10K.

That is, compressed air is supplied from the compressed air source ae to the sealed space (6) via the air supply pipe until the internal pressure of the sealed space (6) reaches, for example, 10 atmospheres. As a result, static pressure is applied to the coating film aη, and isotropic pressure acts on the entire surface of the coating film aη. Therefore, bubbles α existing in the coating film αη
&... is crushed and disappears, and the coating film Uη
The film thickness is also made uniform (see Part 3).

As mentioned above, since the coating film forming apparatus of this embodiment applies static pressure to the formed coating film (171),
The thickness of the coating film αη becomes uniform, bubbles, etc. disappear, and a coating film αη of high quality can be obtained. Therefore, special effects can be achieved by introducing this device into an LSI or liquid crystal manufacturing process.

In the above example, static pressure was applied after the coating film was formed, but the coating agent (4) was dropped and the plate to be coated was applied while the sealed space (6) was pressurized. The rotation (1) may also be performed. Further, the gas for applying equal pressure is not limited to air, and may be other gases such as Nl (nitrogen), CO2 (oxygen dioxide), and Ar (argon). Furthermore, the supply of the coating agent (4) is not limited to the dropping method;
The required amount may be ejected from the nozzle at one time.

Furthermore, instead of the vacuum chuck, the machine 1'' may be fixed using an electrostatic chuck or a jig.

〔Effect of the invention〕

The coating film forming device of the present invention can equalize the thickness of the coating film by applying static pressure to the coating film applied to the adhered surface, and eliminate defective areas such as air bubbles. As a result, a high quality coating film can be obtained. Therefore, the device of the present invention exhibits special effects when introduced into the manufacturing process of LSIs, liquid crystals, and the like.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of a coating film forming apparatus according to an embodiment of the present invention, and FIGS. 2 and 3 are sectional views showing the formed coating film. (1)...Plate to be coated (object to be coated) (2)...Holding section (3)...Sealing section (4)...Coating agent (5)...Coating agent supply section (7)...Pressure part

Claims (1)

[Claims] a holding part that removably holds a to-be-coated object having a surface to be coated on which a coating film is formed and is rotatably driven around a rotation axis substantially perpendicular to the surface to be coated; a coating agent supply section that supplies a liquid coating agent to the surface of the object to be coated; and a sealing section that forms a sealed space in which the object to be coated held in the holding section is sealed together with the holding section. and a pressurizing section that increases the gas pressure in the sealed space and applies static pressure to the coating film formed on the surface to be coated.