JPH0142625B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a dimension check pattern for checking the accuracy of a pattern formed on a semiconductor substrate or the like.

[Prior art]

Generally, a pattern is formed by selectively exposing a resist film covering an insulating film formed on a semiconductor substrate, and the pattern shape is formed by removing the insulating film by etching. It is easily affected by the type and thickness of the insulating film, the temperature in the atmosphere, and even the etching solution.
Therefore, since it greatly affects the characteristics of semiconductor devices,
In order to form a desired pattern, it is necessary to constantly check the pattern dimensions during the manufacturing process.

Conventionally, the shape used to check the pattern dimensions is a dimension check pattern in which a plurality of rectangular patterns 11, 12, 13 having the same width and spacing are arranged in the same shape, as shown in FIG. The dimensional accuracy of the pattern was measured by setting a micrometer in a microscope and reading the relative ratio of the width and spacing of the dimensional check pattern, and converting it to the actual size, or
This size check pattern must be converted to actual size by measuring the relative ratio of width and spacing using a photograph taken, and it is not possible to directly check the dimensions of the pattern shape, so errors are likely to occur. The drawback was that measurement took time.

Furthermore, as shown in FIG. 2, other conventionally used dimension check patterns have two rows of rectangular pattern groups 201, . …216
In the gaps 21, . . . 25 surrounded by the corners of four rectangular patterns, square patterns 221, . They were arranged in such a way that they gradually got smaller on one side at a constant rate. For example, if the width of the gaps 21, . . . 25 between the rectangular patterns 201, . gap 22, 21 in the direction
are square patterns 222 and 221, each side of which is larger than the square pattern 223 by the length of 2a.
In the gaps 24 and 25 in the right direction, square patterns 224 and 225, each side of which is smaller than the square pattern 223 by a length of 2a, are arranged.

In such a dimension check pattern, when checking the dimensions at the time of etching, if the pattern is etched larger by each side a due to excessive etching, then when checking with a microscope, four rectangular patterns 20 are found in the gap 24.
4,205,214,215 and square pattern 2
It should be observed that the corner with 24 is in contact with the pattern, and therefore, it can be seen that each side of the formed pattern is widened by a, which is a significant improvement compared to the dimension check pattern of the conventional example. However, when we observe this dimension check pattern that has actually been formed, we find that in areas with small gaps compared to the area to be patterned, due to the viscosity of the resist film during the photoresist process, there is a gap between the corners. Furthermore, when patterning the insulating film using an etching solution, the corners are patterned, so that gaps 31, . . . 35 corresponding to the gaps 21, . Since the shape of is observed, the overetching value a, which should originally be checked at the gap 34, is mistaken for the gap 35, and the overetching value is checked as 2a.
Therefore, errors are likely to occur, and furthermore, the pattern standards for the dimension check pattern on the mask pattern are stricter than the original device design standards, so it is necessary to use a mask material that matches the dimension check pattern, which increases costs. There were flaws.

[Purpose of the invention]

An object of the present invention is to provide a dimension check pattern that eliminates the above-mentioned drawbacks and allows highly accurate dimension checks just by directly observing a pattern with a simple shape.

[Structure of the invention]

The check pattern of the present invention has a plurality of identical rectangular pattern rows facing each other at a predetermined interval, the opposite sides of which are parallel to each other, and the pattern spacing gradually increasing by a predetermined amount in one direction. and when the two opposing pattern rows are arranged in one row with one pattern among the two pattern rows as a reference pattern, the pattern intervals are sequential in one direction with respect to the reference pattern. The overlapping width of the patterns is arranged so as to increase by a predetermined amount, and the overlapping width of the patterns is sequentially increased by a predetermined amount on the side opposite to the one direction.

[Explanation of Examples]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 4 is a pattern diagram showing an embodiment of the present invention.

In this embodiment, vertically long rectangular patterns 40 of the same shape are arranged so that opposite sides are parallel to each other.
1,...404, the intervals are l-4a from the left,
1, l+4a, the first pattern row 40 is arranged so that the pattern width increases by a predetermined amount 4a, and the vertically long pattern row 40 of the same shape is arranged so that the opposing sides are parallel. The intervals between the rectangular patterns 411, .
With the rectangular pattern 402 as a reference pattern, the second pattern row 41 is arranged such that the pattern width increases by a predetermined amount 4a.
The pattern intervals 423 to 426 that occur when 0, 41 patterns are arranged in a row are a, 2a, 3a, 4a
The interval b is set so that the right side of the rectangular pattern 402 and the left side of the rectangular pattern 412 match so that the overlapping widths 422 and 421 of the patterns are sequentially increased by a predetermined amount a from a to 2a. It consists of being placed facing each other.

FIG. 5 is a pattern formation diagram when etching a resist film or an insulating film using the dimension check pattern of this embodiment, and shows rectangular patterns 501, . . .
504, 511, . . . 514 are rectangular patterns 401, . . . 404, 411, . . . 41 shown in FIG. 4, respectively.
4, and the result of observation is a rectangular pattern 50
When it is found that the right side of 3 and the left side of the rectangular pattern 513 match, the rectangle 403 corresponding to FIG.
Since it is known in advance that the distance 424 between the right side of the rectangle 413 and the left side of the rectangle 413 is 2a, it is known in advance that the distance 424 is opposite to each other by 2a, so it can be directly read that the formed pattern extends by each side a.

Furthermore, the pattern row 40 arranged in FIG.
By setting the interval b between 41 at least the minimum pattern interval in each process mask, the shape of the pattern does not deform, and the rectangular patterns 401,...40
4, 411, ... 414, when the length in the vertical direction is more than three times as large as in the horizontal direction, finding the coincidence of the rectangular pattern sides by the above-mentioned observation is the difference between the rectangular pattern sides to be observed (the right side of the rectangular pattern 401 and the right side of the rectangular pattern 401). The left side of the rectangular pattern 411,..., the rectangular pattern 40
4 and the left side of the rectangular pattern 414), the margins increase sequentially from a negative interval (overlap width) to a positive interval, so the contrast between each side is easy to distinguish, and the rectangle can be easily Matching points between pattern edges can be identified.

Furthermore, the pattern of this embodiment is very simple and can be formed using standards equal to or lower than pattern design standards for semiconductor devices.

FIG. 6 is a pattern diagram showing another embodiment of the present invention. In this embodiment, the distance between each of vertically elongated rectangular patterns 601, .
As 4a, l, l+4a, the pattern spacing is a predetermined amount.
A first pattern row 60 arranged so as to increase in size by 4a, and a vertically long pattern row 60 of the same shape arranged so that opposing sides are parallel.
Rectangular patterns 611,...6 of the same type as the rectangles arranged in
14 intervals from left to right: l-2a, l+2a,
The second pattern row 6 is arranged such that the pattern interval is sequentially increased by a predetermined amount 4a as l+6a.
1, and a third pattern row 6 which is the same shape as the first pattern row 60 and whose rectangular patterns 601, . . . 604 correspond to rectangular patterns 621, .
2, the pattern intervals 633 to 636 that occur when the pattern rows 60, 61 are arranged as an example in the order of pattern rows 60, 61, 62 from the top with the rectangular pattern 602 as a reference pattern are a, 2a, 3a, 4a. The overlap widths 632 and 631 of the patterns increase by a predetermined amount a sequentially from a to 2a.
Furthermore, the pattern row 61 is
This relationship is also maintained between the pattern row 62 and the rectangular pattern widths 633' to 636' are sequentially increased by a predetermined amount a, and the overlap widths 632' and 631' are also sequentially increased by a predetermined amount a. 602
The right side of the rectangular pattern 612 and the right side of the rectangular pattern 622 match, and are arranged facing each other at an interval b that is equal to or larger than the minimum pattern interval in each process mask.

According to this embodiment, when patterning is performed in which each side is widened by a distance a during etching, it is observed that the right side of the rectangular pattern 603, the left side of the rectangular pattern 613, and the right side of the rectangular pattern 623 coincide with each other. The etching dimensions can be identified more easily and accurately than in the case of the embodiment shown in FIG.

Note that in the above explanation, checking of the dimension check pattern was limited to the time of etching, but the scope of use of the dimension check pattern of the present invention is not limited to checking the pattern accuracy during etching, but of course checking the pattern accuracy of the mask pattern itself. It can also be applied to Further, the dimension check pattern of the present invention is not only applicable to semiconductor devices, but also
It can also be applied to devices that require finer patterns, such as magnetic bubble memory devices.

〔Effect of the invention〕

As explained in detail above, according to the present invention,
Since the dimension check pattern of the present invention has the above-mentioned configuration, it can be formed with standards equal to or lower than the pattern design standards of semiconductor devices, and therefore can be easily mounted on a mask substrate. Furthermore, by observing the external appearance of the semiconductor substrate, the dimensions of the patterned pattern can be easily and accurately read. Therefore, when the dimension check pattern of the present invention is used, for example, in the manufacture of semiconductor devices, it is possible to carry out process control without waste, and it is possible to manufacture high-quality semiconductor devices, thereby greatly improving the yield. can. In particular, the present invention will be most effective when applied to the manufacture of large-scale integrated circuit devices in which patterns are significantly miniaturized.

[Brief explanation of drawings]

1 and 2 are pattern diagrams showing conventional dimension check patterns, FIG. 3 is a pattern diagram actually observed during etching of the dimension check pattern of FIG. 2, and FIG. 4 is an embodiment of the present invention. FIG. 5 is a pattern diagram actually observed during etching of the dimension check pattern of FIG. 4, and FIG. 6 is a pattern diagram showing another embodiment of the present invention. In Fig. 1, 11-13... rectangular pattern, in Fig. 2, 21-25... gap, 20
1-206, 211-216... rectangular pattern,
221-225...Square pattern, in Figure 3, 31-35...Gap, in Figure 4, 4
0,41...Pattern row, 401 to 404,41
1 to 414... rectangular pattern, 423 to 426 and 421 to 422... pattern rows 40 and 41 to 1
Pattern width and pattern overlap width when arranged in rows, 501 to 506, 511 to
516...Etching pattern, in FIG. 6, 60-63...Pattern row, 601-60
4,611-614, 621-624... Rectangular patterns, 633-636, 633'-636' and 631-632, 631'-632'... Pattern rows 60 and 61 and 61 and 62 are arranged in one row, respectively. These are the pattern width and pattern overlap width when

Claims (1)

[Claims] 1. A plurality of rows of identical rectangular patterns arranged so that opposing sides are parallel and pattern spacing increases by a predetermined amount in one direction, facing each other at a predetermined interval. When the pattern rows of the two pattern rows are arranged in one row with one pattern among the two pattern rows as a reference pattern, the pattern intervals are sequentially increased by a predetermined amount in one direction with respect to the reference pattern, A dimension check pattern characterized in that patterns are arranged such that the overlapping width of the patterns increases by a predetermined amount sequentially on a side opposite to the one direction side.