JPH03282546A - Reticule - Google Patents

Abstract

PURPOSE:To detect the misalignment between an alignment mark and a circuit pattern by forming an alignment mark assisting mark to be adjacent to the alignment mark by the same data file as the data file of the circuit pattern. CONSTITUTION:The alignment mark assisting mark 15 is provided apart 3 to 10mum spacing opposite to the alignment mark 14. The data on this mark 15 is formed in the same data file as the data file of the circuit pattern data and is formed simultaneously with the circuit pattern. The mark 15 represents the shape and position of the circuit pattern and a position relation can be checked by visually observing the misalignment quantity from the mark 14. The misalignment between the mark 14 and the circuit pattern is easily detected in such a manner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photomask used in the manufacture of semiconductor devices, and particularly to a reticle used in a stepper.

[Conventional technology]

A stepper is used as a device that can form fine patterns on a wafer with high precision. A reticle is set, and a circuit pattern is formed on the wafer by projection reduction exposure. In order to properly set the reticle on the stepper, alignment marks are formed on the reticle for 1-position alignment.In the manufacturing process of semiconductor devices, multiple circuit pattern masks are used, but if the same type of stepper is used. (1) The exact same alignment mark must be formed at the same position on each reticle.Since each circuit pattern mask is different, the alignment mark data is usually created separately from the circuit pattern data, and the electronics used to manufacture the reticle This constant alignment mark is stored in advance in the beam exposure apparatus and is also formed on the reticle when the reticle is manufactured from the circuit pattern data.

[Problem to be solved by the invention]

Since the reticle produced by the above-described method does not require the creation of data for seven alignment marks for each reticle, the effort required to create the data is reduced, and pattern drawing by an electron beam exposure device is also made easier. However, the fact that the circuit pattern data and the 7 alignment data are in separate data files means that unlike the case where they are in the same data file, there is a possibility of human factors making a mistake in the drawing start point of each data, or an electron beam There is a risk that both pieces of data may not be drawn in the same coordinate system depending on the exposure device. Therefore, it is necessary to confirm that the circuit pattern and alignment mark are in the correct positional relationship.

Inspection methods for confirming this relationship include a method using a comparative inspection machine and a method using a laser coordinate measuring machine. The method using a comparative inspection machine is to select a reference reticle from among the several to several reticles required to manufacture one semiconductor, store it separately as a reference, and compare it with the reference reticle for semiconductor manufacturing. This method measures the amount of misalignment by optically overlapping the patterns of the reticles used, and inspection requires skill and a large amount of time, and requires a standard reticle for each type of semiconductor.

Also, in the method using a laser coordinate measuring machine.

Use the coordinates of the alignment mark as the reference position.

This method inspects the amount of deviation by measuring a measurement pattern whose coordinates are clearly defined in the circuit pattern, so the coordinate data of the measurement pattern is sent to the inspector for each circuit pattern or semiconductor type. There was the complexity of having to communicate with them.

SUMMARY OF THE INVENTION An object of the present invention is to provide a reticle for exposure of a semiconductor device, which eliminates the above-mentioned drawbacks and allows easy detection of misalignment between an alignment mark and a circuit pattern.

[Means to solve the problem]

The reticle of the present invention has a minute alignment auxiliary mark as part of the circuit pattern adjacent to the alignment mark provided for stepper setting, which can check the phase relationship between the alignment mark and the circuit pattern of the semiconductor device. I'm trying to form it.

[Effect]

Since the alignment mark and the alignment auxiliary mark are adjacent to each other, the mutual positional relationship can be easily known. Since the alignment auxiliary mark is a part of the circuit pattern and represents its position, it can be confirmed that the circuit pattern is formed correctly with respect to the alignment mark.

〔Example〕

FIG. 3 is an overall view of the reticle. The reticle has a pattern formed on a glass substrate 11 using a metal thin film such as chromium or chromium oxide. The part of the reticle set on the stepper that is exposed by reduction projection onto the wafer is an inner circuit pattern 1 surrounded by an outer frame pattern 13 for shielding light.
It is 2. An alignment mark 14 is formed on the outside of the outer frame pattern 13 to be used for correct setting on the stepper.

An embodiment of the present invention will be described below. FIG. 1 is an enlarged plan view of the vicinity of the alignment mark 14,
As described above, the alignment mark 14 is formed from data stored in the electron beam exposure apparatus. An alignment auxiliary mark 15 is formed facing this alignment mark 14 with an interval of 3 to 10 μm.

The data of the alignment auxiliary mark 15 is created in the same data file as the circuit pattern data, and is formed at the same time as the circuit pattern. Alignment aid mark 1
5 represents the formation position of the circuit pattern, and the positional relationship can be confirmed by observing the deviation from the alignment mark 14 through internal wear.

Next, a second embodiment will be explained. As shown in the f-plane view of FIG. 2, the alignment mark 14 has a comb pattern 16 with a uniform pitch at its tip. The circuit pattern alignment auxiliary mark 15 also has a comb-shaped pattern 17 with a uniform pitch at its tip, and the comb-shaped pattern 16 and its tip are mutually separated by 5 to 20 JL.
I try to overlap. Here, the pitch of the comb pattern 17 of the alignment auxiliary mark 15 is set to 1 to 27 points higher than the pitch of the comb pattern 16 of the alignment mark 14.
If it is made smaller by 1 m, the amount of deviation can be read accurately with the naked eye.

〔Effect of the invention〕

As explained above, 1. The present invention is achieved by creating 17 alignment auxiliary marks adjacent to alignment marks using the same data file as the circuit pattern.
This has the effect of making it extremely easy to confirm that the circuit pattern and alignment mark are in the correct positional relationship. Since the alignment mark has a common shape for each reticle and the coordinates are common and clear, it is easy to create data for the alignment aid mark. Therefore, according to the present invention, the effect of having the circuit pattern and the alignment mark in separate files can be reliably achieved.

[Brief explanation of drawings]

Figures 1 and 2 are plan views of embodiments of the present invention. FIG. 3 is a plan view showing the entire reticle. 11...Crow board, 12...Circuit pattern 13... Outer frame pattern, 14... Alignment mark, 15... Alignment auxiliary mark 16 17...Comb pattern. Special permission Out wish Man ■ Hondenki Co., Ltd.

Claims (1)

[Claims] In a reticle for exposure of a semiconductor device, a minute alignment auxiliary mark is placed as part of the circuit pattern adjacent to the alignment mark provided for stepper setting, so that the mutual positional relationship between the alignment mark and the circuit pattern of the semiconductor device can be verified. An exposure reticle characterized by being formed as follows.