JPH04209520A - Rotary coating apparatus - Google Patents

Abstract

PURPOSE:To simplify the whole constitution of the title apparatus, to eliminate a trouble regarding a space and to easily from a resist film having a required film thickness by a method wherein a solvent supply pipe is connected to a resist nozzle and the viscosity of a resist liquid is adjusted according to the supply amount of a solvent. CONSTITUTION:At a rotary coating apparatus 1, a solvent B supplied from a solvent supply pipe 7 is injected into the upstream-side inside of a resist nozzle 6 filled with a resist liquid R which has been supplied through a resist supply pipe 5 and whose viscosity has not yet been adjusted. The solvent B is diffused into the liquid R and is mixed uniformly at the downstream-side inside of the nozzle 6, i.e., between an opening 6a at the nozzle 6 and an opening 7a at the supply pipe 7. As a result, the viscosity of the liquid R is adjusted according to the supply amount of the solvent B which is mixed with the liquid. As a result, the liquid R whose viscosity has been adjusted is dropped immediately form the opening 6a at the nozzle 6 and is supplied to the surface of a wafer W. Then, a vacuum chuck 2 is turned at high speed by using a rotary rod 3; the liquid R is spread to the whole face of the wafer W by means of centrifugal force; a resist film having a film thickness according to the viscosity can be formed on the surface.

Description

[Detailed description of the invention]

[00011

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spin coating apparatus used for forming a resist film of a desired thickness on the surface of a wafer. [0002] Conventionally, a spin coating apparatus 20 having a schematic configuration as shown in FIG. 3 has been generally used in a photolithography process of a semiconductor manufacturing process. That is, this rotary coating device 20 includes a vacuum chuck 21 that sucks and holds a horizontally placed wafer W and rotates around a vertical axis, and a spin cup that is disposed surrounding the vacuum chuck 21 and the wafer W. 22 and
It is provided with a plurality of resist supply pipes 23 that respectively supply resist liquids R adjusted to different viscosities in advance. A resist nozzle 24 is provided at the lower end of each of the resist supply pipes 23, and the resist liquid R is dripped from the opening 24a of each resist nozzle 24 and is supplied to the rotation center position on the surface of the wafer W. It has become. [0003] On the other hand, when forming a resist film with a required thickness on the surface of the wafer W using this spin coating device 20, first, the wafer W is held by suction on the upper surface of the vacuum chuck 21, and then , a resist liquid R having a viscosity corresponding to the thickness of the resist film to be formed is dropped from one of the resist nozzles 24 to be supplied to the rotational center position on the surface of the wafer W. After that, when the rotary rod 25 supporting the vacuum chuck 21 is rotated at high speed, the supplied resist liquid R is spread over the entire surface of the wafer W by centrifugal force, and a thick film is formed on the surface of the wafer W. A thin resist film (not shown) will be formed. [0004]

By the way, in the spin coating apparatus 20 having the conventional structure, since it is provided with a plurality of resist supply pipes 23, the structure of the entire apparatus is not only complicated, but also resists having different viscosities are It was necessary to install a nozzle bottle (not shown) for each liquid R, which caused an inconvenience in terms of space. Furthermore, since the viscosity of the resist liquid R has been adjusted in advance, it is necessary to adjust the number of rotations of the rotating rod 25 in order to further adjust the thickness of the resist film. Normally, the selection range for the number of rotations is set to be narrow to some extent, and this set rotation speed is currently decreasing as the diameter of the wafer W becomes larger. Rotating rod 2 with priority given to the viscosity of R.
It was extremely difficult to increase the rotation speed of the 5 as much as necessary. [00051] The present invention has been devised in view of the current situation, and is capable of simplifying the overall configuration of the apparatus and eliminating inconveniences in terms of space, and also allows the viscosity of the resist liquid to be adjusted arbitrarily. It is an object of the present invention to provide a spin coating apparatus configured to easily form a resist film of a required thickness. [0006]

[Means for Solving the Problems] In order to achieve the above object, the rotary coating apparatus according to the present invention has a vacuum chuck that holds a horizontally placed wafer by suction and rotates around a vertical axis. , a resist supply pipe that supplies a resist solution, and a resist nozzle provided at the lower end of the piping that drops the resist solution onto the wafer surface, and a solvent that supplies a solvent for adjusting the viscosity of the resist solution to the resist nozzle. A supply pipe is connected and penetrated to the inside (-) and the opening of the solvent supply pipe is located upstream at a predetermined distance from the opening of the resist nozzle. [0007]

[Operation] According to the above structure, the solvent supplied through the solvent supply pipe and the resist liquid supplied from the resist supply pipe are mixed in the resist nozzle, and the viscosity of this resist liquid is It will be adjusted depending on the amount. [0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. [0009] FIG. 1 is a cross-sectional view showing a schematic configuration of a spin coating apparatus according to this embodiment, and FIG. 2 is an enlarged cross-sectional view showing a schematic configuration of a resist nozzle, which is a main part thereof, and reference numeral 1 in FIG. is a rotary coating device. [00101 This rotary coating device 1 includes a vacuum chuck 2 that attracts and holds a wafer W placed horizontally, and a rotating rod 3 that supports the vacuum chuck 2 and rotates around a vertical axis.
, a spin cup 4 disposed surrounding the vacuum chuck 2 and the wafer W, and a single resist supply pipe 5 for supplying a resist liquid R whose viscosity is not adjusted. A resist nozzle 6 is provided at the lower end of the resist supply pipe 5, and the resist liquid R is dripped from the opening 6a and is supplied to the rotational center position on the surface of the wafer W. . [00117Furthermore, this resist nozzle 6 is shown in FIG.
As shown, a solvent supply pipe 7 for supplying ECA (ethyl cellosolve acetate) and the like as a solvent B for adjusting the viscosity of the resist liquid is connected in communication. The inner end of the solvent supply pipe 7 passes through the resist nozzle 6 and is drawn into the interior thereof, while the lower a is positioned upstream at a predetermined distance from the opening 6a of the resist nozzle 6. It is being In addition, at this time, the outer diameter of the solvent supply pipe 7 is set to about 0.5 to 1.0 mm, which does not prevent the flow of the resist liquid R inside the resist nozzle 6, while the open lower a and the resist nozzle 6 opening 6a
The spacing between the two is set at about 10 to 20 mm. [0012] Next, the spin coating device 1 having the above configuration
The operation and effects of this will be explained. (0013) First, when the solvent B supplied from the solvent supply pipe 7 is injected into the upstream side of the resist nozzle 6 filled with the resist liquid R with unadjusted viscosity supplied through the resist supply pipe 5, this solvent B is The solvent will be diffused into the resist liquid R and will be uniformly mixed inside the downstream side of the resist nozzle 6, that is, between the opening 6a of the resist nozzle 6 and the open lower a of the solvent supply pipe 7. As a result, the viscosity of this resist liquid R is adjusted according to the supply amount of solvent B mixed with it, and the resist liquid R whose viscosity has been adjusted is immediately discharged from the opening 6a of the resist nozzle 6. It is dripped onto the surface of the wafer W. When the vacuum chuck 2 holding the wafer W by suction is rotated at high speed by the rotating rod 3, the supplied resist liquid R is applied to the wafer W by centrifugal force.
A resist film (not shown) is formed on the surface of the wafer W with a thickness corresponding to its viscosity.
will be formed. [0014]

[Effects of the Invention] As explained above, according to the spin coating apparatus according to the present invention, a plurality of resist supply pipes and nozzle bins are provided for supplying a resist solution whose viscosity has been adjusted as in the conventional example. Since this is no longer necessary, the overall configuration of the spin coating device can be simplified and space problems can be eliminated. In addition, the viscosity of the resist solution can be adjusted arbitrarily by adjusting the amount of solvent supplied, so a resist film of the required thickness can be easily formed without adjusting the rotation speed of the rotating rod. You can also get the effect of being able to.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a schematic configuration of a spin coating apparatus according to an embodiment.

FIG. 2 is an enlarged cross-sectional view showing a schematic configuration of a resist nozzle, which is a main part of the spin coating device.

FIG. 3 is a sectional view showing a schematic configuration of a rotary coating device according to a conventional example.

[Explanation of symbols]

1　Rotary coating device 2 Vacuum chuck 5 Resist supply piping 6 Resist nozzle 6a Opening A Solvent supply piping 7a Opening B Solvent R resist liquid W Wafer

[Figure 3]

Claims (1)

[Claims] Claims: 1. A vacuum chuck that sucks and holds a horizontally placed wafer and rotates around a vertical axis; a resist supply pipe that supplies a resist solution; A resist nozzle that drips the liquid is connected to the resist nozzle, and a solvent supply pipe that supplies a solvent for adjusting the resist liquid viscosity is connected to the inside, and the opening of the solvent supply pipe is connected to the opening of the resist nozzle. A rotary coating device characterized in that it is located upstream at a predetermined distance from the rotary coating device.