JPH0444217A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To eliminate the needs of preparing resist liquids having different viscosities, of using low-viscosity resist liquids for forming thick resist films, and of controlling the dropping quantity of a resist liquid with high accuracy by applying the resist liquid while the ambient environment of a semiconductor substrate is set to a high-pressure state higher than the atmospheric pressure. CONSTITUTION:A semiconductor substrate 2 is set on a chucking table 3 in a sealed coater cup 5. After setting the substrate 2, air or a gas, such as N2, etc., is injected into the cup 5 from a gas pipe 6 connected with the cup 5 until the inside pressure of the cup 5 reaches a prescribed level. Then a resist film having a uniform thickness is formed on the substrate 2 by dropping resist liquid onto the substrate 2 from a resist dropping nozzle 1 while rotating the substrate 2 by means of a spin motor 4. At the time of applying the resist liquid, the vaporizing speed of the solvent contained in the resist liquid can be controlled by setting the ambient environment to the high-pressure state and the resist film thickness can be controlled by changing the pressure. In other words, changes in the resist film thickness can be coped with by only changing the pressure inside the coater cup 5 without changing the viscosity of the resist liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and particularly to an improvement in a technique for applying a resist liquid onto a semiconductor substrate.

[Conventional technology]

Conventionally, when applying a resist solution onto a semiconductor substrate, the environment around the semiconductor substrate has been kept at atmospheric pressure.

[Problem to be solved by the invention]

Normally, when manufacturing semiconductors, the process of applying resist liquid involves more than 10 steps, and the resist film thickness also varies.
Generally, there are two to three types of conditions. by the way,
In order to obtain a desired resist film thickness, it is necessary to change the viscosity of the resist liquid to obtain each resist film thickness, and the viscosity of the resist liquid must be changed for each condition of the resist film thickness.

As the regulations for resist film thickness increased, the number of resist solutions with different viscosities increased, making the work more difficult.

In order to produce an even thinner resist film, a resist solution with a low viscosity is essential, but there is a problem in that the lower the viscosity, the more difficult it becomes to control the resist solution dropping tray with high precision.

The present invention solves the problems of the conventional semiconductor device manufacturing method, and the purpose is to provide a semiconductor device manufacturing method that can control the resist film thickness using a simpler method. It's there to provide.

[Means to solve the problem]

The method for manufacturing a semiconductor device according to the present invention is characterized in that when applying the resist liquid, the environment around the semiconductor substrate is brought into a high pressure state equal to or higher than atmospheric pressure, and the resist liquid is applied.

〔Example〕

1 to 6 are cross-sectional views of a semiconductor device according to an embodiment of the present invention.

A semiconductor substrate 2 is set on a chucking table 3 in a sealed coater cup 5. After that, air or N2 is supplied from the gas pipe 6 connected to the coater cup 5.
etc. is injected into the cup until it reaches a predetermined pressure. Next, the resist solution is dripped onto the semiconductor substrate 2 from the resist dropping nozzle 1, and the semiconductor substrate 2 is rotated by the spin motor 4 to be uniformly distributed over the semiconductor substrate 2. Form a resist film.

By the way, the factors that determine the resist film thickness are the viscosity of the resist solution, the rotation speed of the semiconductor substrate after dropping the resist solution,
There are three possible evaporation rates at which the solvent evaporates from the resist during rotation. 21-4.15 are cross-sectional views of semiconductor devices manufactured by conventional methods. To briefly explain the conventional method, first, a semiconductor substrate 2 is set on a chucking table 3 in a coater cup 15 that is not particularly sealed. The semiconductor substrate 2 is rotated by the spin motor 4 to form a uniform resist film on the semiconductor substrate 2. In the conventional method, the inside of the coater cup is not sealed, so the environment around the semiconductor substrate 2 is always maintained at atmospheric pressure. Therefore, the evaporation rate of the solvent from the resist during resist coating is always kept constant. Furthermore, regarding the rotation speed, at low speeds the in-plane uniformity of the resist film thickness deteriorates, and at high speeds there is a limit to the ability of the spin motor.
The rotation speed per minute is the practical range, and within this rotation speed, the film thickness could not be changed significantly. Therefore, conventionally,
A desired resist film has been obtained by changing the viscosity of the resist solution.

According to the present invention, by setting the environment around the semiconductor substrate 2 to a high pressure state during resist application, it is possible to control the evaporation rate of the solvent in the resist solution, and by changing the pressure, the resist film thickness can be adjusted. For example, when the condition is such that a film thickness of 2 μm can be obtained using the conventional method, simply setting the inside of the coater cup 5 to 2 atmospheres will allow control.
The resist film thickness changes from 2 μm to 11 m. That is, even if some resist film thickness is required, it can be handled by simply changing the pressure state within the coater cup 5 without changing the viscosity of the resist liquid.

〔Effect of the invention〕

As described above, according to the present invention, the resist film thickness can be controlled by changing the high pressure state inside the coater cup, which eliminates the need to prepare resist solutions with different viscosities, simplifying the work. Become. Furthermore, the low viscosity resist liquid that is required when the resist film thickness is thin is no longer required, and the highly accurate control of the amount of resist liquid dropped is also no longer necessary, which is expected to improve quality.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a semiconductor device according to an embodiment of the present invention. FIG. 2 is a sectional view of a conventional semiconductor device. Applicant: Seiko Epson Corporation

Claims (1)

[Claims] A method for manufacturing a semiconductor device, characterized in that when applying a resist liquid onto the surface of a semiconductor substrate, the environment around the semiconductor substrate is brought to a high pressure state equal to or higher than atmospheric pressure, and the resist liquid is applied.