JPS61125132A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To remove variation of positioning accuracy by a method wherein positioning is performed using a positioning template of a photomask containing a bisector of a polygonal angle or parallel line thereof of the positioning pattern in a photo-lithography process. CONSTITUTION:A pattern 1 is a positioning pattern on the surface of a substrate, while a broken-lined pattern 5 is a one being enlarged proportionally on a surface of a semiconductor, and a broken-line pattern 6 is a one being reduced proportionally on the surface of the semiconductor. At the positioning pattern (b) of a photomask, two rectangles 3, which contain bisectors of regular square angles and parallel straight line of the pattern 1 with margin of positioning are disposed and they are provided to each angle sections. For positioning the pattern (b) and (a), the regular square angle corners of the pattern 1 are set between the margins 4 of positioning. At this time, even if the regular square 1 is enlarged to the shape of the broken-line 5 at previous process or is reduced to the broken-line 6, the angle corners can be taken in the margin of positioning 4, thereby the accuracy of positioning does not change.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a semiconductor device, and in particular, 7) I)
This invention relates to a method for manufacturing a semiconductor device that is an improvement on the J. Sogerahuie process.

[Conventional technology]

Conventionally, in the photolithography process, alignment patterns are used to match the positional relationship between the photomask and the semiconductor substrate surface in order to match the pattern already processed on the semiconductor substrate surface. A pattern was previously formed on the surface, and alignment was performed based on the positional relationship between the straight lines of the pattern and the straight lines of the photomask pattern. Figure 4 fat, (b), tc
+ is a diagram for explaining a conventional alignment pattern and its alignment method. Figure 4 (al.
For example, a square pattern slightly smaller than the square pattern formed on the surface of the semiconductor substrate is provided on the photomask, as shown in FIG.
The substrate and photomask are aligned by fitting the square pattern of the photomask inside the square pattern on the substrate surface and arranging them as shown in Figure 4 (C1). The dimensions of each side of 1 and Figure 4 (
It is designed so that the dimensions of each side of the square 2 shown in bl are different, and if the square 2 is inside the square 1, there is no problem, but if it protrudes, it is a defect.

[Problem that the invention seeks to solve]

However, depending on the process, the pattern shown in FIG. 4 [al] on the surface of the semiconductor substrate that has already been formed may be proportionally enlarged or reduced, and if it is enlarged, pattern 1 in FIG. Even if pattern 2 is included without protruding, it may be defective, and if it is reduced, it may not be possible to insert pattern 2 in figure 4 (bl) into pattern 1 in figure 4 (al). It had the disadvantage of getting a nuisance.

The present invention eliminates such drawbacks and provides lithography that does not change the alignment accuracy even in the photolithography process of a semiconductor device manufacturing method, which has a process in which an alignment pattern formed on the surface of a semiconductor substrate is proportionally enlarged or reduced. An object of the present invention is to provide a method for manufacturing a semiconductor device that includes steps.

[Means for solving problems]

In the method for manufacturing a semiconductor device of the present invention, in the IJ sogerafye step of processing the main surface of the semiconductor substrate, steps of the semiconductor substrate, steps of the film on the substrate, or straight lines formed due to the presence or absence of the film are formed on the main surface of the semiconductor substrate. For a pattern having polygonal corners, an alignment pattern for alignment with a photomask used in exposure is made by using a bisector of the corner of the polygonal corner or a parallel line thereof. It is constructed by forming the pattern into a shape having the same shape and aligning both patterns.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram for explaining an alignment pattern and an alignment method for explaining a first embodiment of the present invention.

In FIG. 1 1a), pattern 1 indicated by a solid line is the same pattern as FIG. Further, pattern 6 is an alignment pattern on the surface of the semiconductor substrate which is proportionally reduced.

Figure 1 (bl is the alignment pattern of the photomask used in the present invention. Figure 1 (al) is a rectangle 3 that includes a straight line parallel to the bisector of the corner of the square in pattern 1, and alignment margin 4 is Two pieces are placed side by side at each corner.

To align the pattern in Figure Ml (bl) and the pattern in Figure 2 1al, align the corner of the square of pattern 1 with an alignment margin of 40 as shown in Figure 1 (C1).At this time, the square of pattern 1 Even if it is enlarged in the previous process and becomes like the broken line in 5, or if it is reduced and becomes like the broken line in 6, the corner can be placed within the alignment margin of 4, and alignment accuracy will not change. .

FIGS. 2A and 2B are diagrams for explaining a mask alignment pattern and an alignment method for explaining a second embodiment of the present invention. The mask alignment pattern 7 in FIG. 2 1al is formed in a triangular shape including a straight line parallel to the bisector of the corner of the square of pattern 1, and is arranged in contrast to the bisector of the corner. . In this case as well, the same effect as in the first embodiment of J-C can be obtained by overlapping them as shown in FIG. 2(b).

FIG. 3 (al, (bl, (C1 is the third embodiment of the present invention)
FIG. 2 is a diagram for explaining an alignment pattern on the surface of a semiconductor substrate, an alignment pattern of a photomask, and an alignment method for explaining an embodiment of the present invention.

In FIG. 2 1al, (b) and (C), 8 is an alignment pattern on the semiconductor substrate, 9 is an alignment pattern on the semiconductor substrate surface proportionally enlarged, 10 is an alignment pattern on the semiconductor substrate surface proportionally reduced, Further, 11 is an alignment pattern of the photomask. In this case as well, the alignment pattern 11 of the photomask is formed into a square shape including a straight line parallel to the bisector of the corner of the square of the pattern 8. There are effects similar to those of the embodiment.

In the above embodiment, an example was described in which the alignment pattern of the photomask included a straight line parallel to the bisector of the corner of the alignment pattern on the surface of the semiconductor substrate.
It may be a center line, or it may be a rectangular pattern including a center line with width or a center line with a frame in order to provide alignment margin.

〔Effect of the invention〕

As explained above, according to the present invention, in the photolithography process of a semiconductor device manufacturing method that includes a process in which a nine-metal alignment pattern formed on a semiconductor substrate is proportionally enlarged or reduced, the alignment pattern is (By aligning using a photomask alignment pattern that includes the bisector of the corner of the polygon or its parallel lines)
There is no change in alignment accuracy, and it is possible to obtain a level of alignment accuracy.

[Brief explanation of drawings]

Figure 1 Tal ~ (C1, Figure 2 (al, (bl,
FIG. 3 (aJ to fcl are explanatory diagrams for explaining the alignment pattern on the surface of the semiconductor substrate, the alignment pattern of the photomask, and the alignment method for explaining the present invention in detail, and FIG. 4 [al ~ (C1 is an explanatory diagram for explaining the alignment pattern of the semiconductor substrate, the photomask alignment pattern, and the alignment method, which is not used to explain the conventional method. 1. The pattern of the semiconductor substrate surface alignment pattern, &
3.7.11... Alignment pattern of photomask, 4... Alignment margin, 5.9... Alignment pattern of proportionally enlarged semiconductor substrate surface, 6 .10
.....Alignment pattern on the surface of a semiconductor substrate proportionally reduced. Agent Patent Attorney Susumu Uchihara 〜Pa'：”'＋、
+ rod / times (al (b) 2nd fJ (刹稟3 fig.

Claims (1)

[Claims] In a photolithography process for processing the main surface of a semiconductor substrate, a pattern having polygonal corners formed by steps of the substrate, steps of a film on the substrate, or straight lines due to the presence or absence of a film on the main surface of the semiconductor substrate is exposed to light. An alignment pattern for alignment with a photomask used in the process is formed in a shape having a bisector of the corner of the pattern having polygonal corners or a parallel line thereof, and both patterns are aligned. A method for manufacturing a semiconductor device, characterized in that: