JPH02100313A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To enable a resist with a flat surface to be coated by fully coating even the stage difference on a semiconductor substrate and thickly rotating- coating the resist to achieve a uniform film, and then performing etching to a needed film thickness. CONSTITUTION:A resist 2 is subjected to rotation-coating using a spinner so that a semiconductor substrate 1 with stage difference may be fully coated to achieve a uniform film. Then, with oxygen plasma etching. the film thickness of the required resist 2 can be made. Thus, since the resist 2 is thickly coated and the uniform film is etched, the resist 2 can be coated even on the semiconductor substrate 1 with a large stage difference so that the surface may be flat.

Description

Detailed Description of the Invention (Industrial Application Field) This invention relates to a method for manufacturing a large-scale integrated circuit (LSI), and in particular a resist coating method that can coat a semiconductor substrate with a resist evenly and on a flat surface. It is related to.

[Prior Art] In general, the manufacture of semiconductor devices requires many layers of processes, so alignment precision is required to accurately overlap mask patterns required for each process. In order to improve this alignment accuracy, it is necessary to apply the resist evenly and flatly even on a semiconductor substrate with large steps. Conventionally, a spinner was used to spin and coat the resist at a rotational speed corresponding to the required film thickness. Third
The figure is a cross-sectional view showing a state in which a resist is conventionally applied on a semiconductor substrate with steps. In the figure, (1) is a semiconductor substrate with a step, and (2) is a resist.

Next, the manufacturing method will be explained. The semiconductor substrate (1) is placed on a spinner, and the resist (2) is applied to the surface of the semiconductor substrate (1) while being rotated at a rotation speed determined according to the required film thickness of the resist (2) to be applied.

[Problem to be solved by the invention]

Conventional resist coating methods for manufacturing semiconductor devices are carried out using the method described above. Therefore, in areas with severe level differences, the level difference coverage of the resist deteriorates, as shown in Figure 3, and the surface of the semiconductor substrate is coated. There was a problem that the resist could not be applied flatly.

This invention was made in order to solve the above-mentioned problems, and aims to provide a method for manufacturing a semiconductor device that can improve the step coverage of the resist even in areas with severe steps and can apply the resist to a flat surface. purpose.

(Means for Solving the Problems) The resist coating method for manufacturing a semiconductor device according to the present invention includes spin-coating a resist thickly so as to sufficiently cover the stepped portions on the semiconductor substrate and form a uniform film. Thereafter, etching is performed to obtain the required film thickness.

(Function) The resist coating method for manufacturing a semiconductor device according to the present invention is to spin coat the resist thickly so as to sufficiently cover the steps on the semiconductor substrate and to form a uniform film, and then to apply the resist to the required film thickness. Since it is etched, a resist with a flat surface can be applied.

(Example) As an example of the present invention, an example in which a spinner is used during resist application and oxygen plasma is used during resist etching to apply resist onto a semiconductor substrate will be described below. Figure 1 is a cross-sectional view showing the state in which resist is applied on a semiconductor substrate, and Figures 2 (a) and (b).
2A and 2B are cross-sectional views shown according to the steps of a resist coating method. In the figure, (I) is a semiconductor substrate, and (2) is a resist.

Next, a method for applying a resist (2) on a semiconductor substrate (1) will be explained according to FIG. As shown in FIG. 2(a), a thick resist (2) is applied by spin coating using a spinner so that the semiconductor substrate (1) having one step difference is sufficiently covered with a uniform film. Next, as shown in FIG. 2(b), the necessary resist (2) is formed by # elementary plasma etching.
Make the film thickness . In this way, apply resist (2) thickly.
Since this is a method of etching a uniform film after etching, it is difficult to etch a semiconductor substrate (1) with large steps as shown in Figure 1.
The resist (2) can be coated evenly on the top surface.

In addition, in the above example, oxygen plasma etching was used to make the resist (2) thickly coated on the semiconductor substrate (1) to the required film thickness. Even if wet etching of a meso-soluble material is used, the same effect as in the embodiment described above can be obtained.

(Effects of the Invention) As described above, according to the present invention, the step portions on the semiconductor substrate are sufficiently covered, and the resist is spin-coated thickly to form a uniform film, and then the resist is applied to the required film thickness. Since the resist is applied onto the semiconductor substrate by etching, a resist film with a flat surface can be obtained even on a semiconductor substrate with severe steps.

[Brief explanation of drawings]

Figure m1 is a cross-sectional view showing a state in which a resist is applied to a semiconductor substrate according to an embodiment of the present invention, and Figures 2 (a) and (
b) is a cross-sectional view showing the steps of a resist coating method according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view showing a state in which a resist is applied by a conventional method. In the figure, (
+) is a semiconductor substrate, and (2) is a resist. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Agent Masuo Oiwa Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a resist coating method for manufacturing a semiconductor device, a first step of spin-coating a thick resist using a spinner so as to sufficiently cover the stepped portions on the semiconductor substrate and form a uniform film; A method for manufacturing a semiconductor device, including a second step of etching a resist film coated on the surface to a required thickness.