JPH0318178B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for forming patterns having multiple types of spacing, including fine spacing, in the manufacturing process of semiconductor devices.

[Prior art]

Conventionally, there has been a method shown in FIG. 1 for transferring patterns having two or more sizes of intervals onto a photosensitive resin film on a layer to be processed formed on a substrate. In the figure, 1 is a substrate, 2 is a layer to be processed, and 3 is a photosensitive resin film.

Next, a conventional pattern forming method will be explained.
When a photosensitive resin film 3 is formed on a processed layer 2 formed on a substrate 1 by, for example, a spin coating method, the result is as shown in FIG. 1a. Thereafter, using a normal exposure device, mask plates (not shown) on which a desired pattern is drawn are stacked and irradiated with light, and the photosensitive resin film 3 is irradiated with the light that has passed through the mask plates. In the subsequent development process, the irradiated portions of the photosensitive resin film 3 if it is a positive type, and the unirradiated portions of the photosensitive resin film 3 if it is a negative type, are removed by a developer. Here, if there is a pattern drawn on the mask board that has two or more types of gaps 4 and 5 of different sizes, especially if the smaller gap 5 is 2 μm or less, the developer Since the penetration is poor, even when the development is completed at the large pattern interval 4, it is not completed at the small pattern interval 5, resulting in a development residue 6 due to insufficient development, as shown in FIG. 1B. Second
The figure is a plan view of the situation. In this case, if development is carried out in accordance with the completion of the development of the smaller pattern interval 5, the larger pattern interval 4 will be overdeveloped, resulting in a large deviation in the pattern dimensions. Thereafter, the layer 2 to be processed is etched using the developed photosensitive resin film 3 as a mask, and the development residue 6 shown in FIG. 1b and FIG.
cause. An example of a cross-sectional view of the pattern when the photosensitive resin film 3 is removed after etching is shown in FIG. 1c. This etching residue 7 short-circuits adjacent patterns.

[Summary of the invention]

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional method, and by forming a convex pattern in advance on the lower layer of the processed layer where a small pattern interval is to be transferred, it is possible to create a pattern between adjacent patterns. The purpose is to ensure separation.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4.
The diagram will be explained. In the figure, 1 is the substrate, 2
3 is a layer to be processed, 3 is a photosensitive resin film, and 8 is a convex pattern formed on the lower layer of the layer to be processed.

As shown in FIG. 3a, convex patterns 8 are formed on the substrate 1 at positions where small pattern intervals will be drawn later. After that, the layer 2 to be processed is formed, and the photosensitive resin film 3 is formed on it by, for example, a spin coating method. , as shown in Figure b, is considerably thinner than other parts. Thereafter, after going through the exposure and development steps similar to those in the conventional method, the result is as shown in FIG. As can be seen from FIG. c, the development can be completed at the small pattern interval 5 almost at the same time as the development at the large pattern interval 4 is completed. FIG. 4 is a plan view of FIG. 3c, and there is no development residue seen in the conventional method. An example of a cross-sectional view of the pattern when the photosensitive resin film 3 is removed after etching the layer 2 to be processed using the photosensitive resin film 3 with this pattern as a mask is shown in FIG. 3d.

〔Effect of the invention〕

As described above, according to the present invention, since the convex pattern is previously formed in the portion where the small pattern interval is to be transferred, it is possible to reliably form a pattern having a mixture of various sizes.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional side view showing the state at each stage for explaining an example of a conventional pattern forming method, Fig. 2 is a plan view at the stage of Fig. 1b, and Fig. 3 is an embodiment of the present invention. FIG. 4 is a cross-sectional side view showing states at each stage for explaining the pattern forming method according to an example, and FIG. 4 is a plan view at the stage of FIG. 3c. In the figure, 1 is a substrate, 2 is a layer to be processed, 3 is a photosensitive resin film, 4 is a large pattern interval, 5 is a minute pattern interval, and 8 is a convex pattern. In addition,
The same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. When forming a pattern having multiple types of intervals including minute intervals on a layer to be processed formed on a substrate, forming a convex pattern on the substrate at a portion of the layer to be processed where the minute intervals are to be formed. Then, the to-be-processed layer is formed on the substrate including the top of the convex pattern, and the to-be-processed layer is formed by photolithography using a photosensitive resin film formed on the to-be-processed layer. A method for forming a pattern, comprising forming the desired pattern as described above.