JP2636541B2 - Inspection method of pattern accuracy - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pattern accuracy inspection method for monitoring the pattern accuracy of an exposure apparatus.

In recent years, reticle fabrication has been performed at the limit of the pattern arrangement accuracy of an exposure apparatus. Therefore, it is required to guarantee the accuracy for each reticle. The present invention can be used as a method for satisfying this requirement.

[0003]

2. Description of the Related Art In a conventional reticle fabrication, the following method is performed to guarantee the pattern arrangement accuracy.

[0004] A reticle for accuracy monitoring is periodically created. Measure the dimensions of specified patterns on the manufactured reticle.

[0005]

However, in the conventional method, it was not possible to find a positional displacement (due to a change over time in the exposure apparatus) that occurred during long-time exposure.

In the above method, it takes a considerable amount of time to perform all reticles. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method which can easily inspect a pattern arrangement position shift generated at the time of reticle pattern drawing, and guarantees pattern arrangement accuracy for each reticle.

[0007]

Means for Solving the Problems To solve the above-mentioned problems, at the start and end of reticle pattern drawing, the inspection pattern (1A) at the start of drawing and the drawing pattern with a gap shifted by the placement accuracy on the dry plate are provided. This is achieved by a pattern accuracy inspection method in which the inspection pattern (1B) at the time of termination is overlaid and drawn, and the gap is observed to verify the pattern arrangement accuracy.

[0008]

According to the present invention, when a reticle pattern is drawn, at the start and end of the drawing, the test patterns shifted by the placement accuracy are respectively superimposed and drawn on a specific position on the dry plate, so that the two test patterns overlap. Therefore, the arrangement accuracy can be easily guaranteed.

As a result, since the inspection pattern is drawn for each reticle, the pattern arrangement accuracy for each reticle can be guaranteed. FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 1 is a plan view of an inspection pattern, wherein 1A is an inspection pattern at the start of writing, 1B is an inspection pattern at the end of writing, and a gap between the outer circumference of the inspection pattern 1A and the inner circumference of the inspection pattern 1B is a value of arrangement accuracy. (For example, about 0.1 to 0.5 μm).

[0011]

FIG. 2 is a plan view showing a drawing arrangement on a dry plate for explaining an embodiment. In the figure, 1 indicates inspection pattern 1A,
1B, 2 is a reticle pattern, and 3 is a dry plate.

The inspection pattern 1 is drawn at a plurality of arbitrary positions outside the reticle pattern 2. Fig. 3 (A) to (C)
FIG. 9 is a plan view for explaining the result judgment of the example.

If the gap between the outer circumference of the test pattern 1A and the inner circumference of the test pattern 1B has disappeared, it is determined to be defective.
FIG. 3 (A) shows a normal case, FIG. 3 (B) shows a case where the test pattern 1B is shifted upward and becomes defective, and FIG. 3 (C) shows a test pattern 1B.
1B is shifted to the right and becomes defective.

[0014]

According to the present invention, it is possible to easily inspect the positional displacement of a pattern generated at the time of drawing a reticle pattern, and it is possible to guarantee the pattern placement accuracy for each reticle.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a plan view showing a drawing arrangement on a dry plate for explaining the embodiment.

FIG. 3 is a plan view for explaining the result judgment of the embodiment.

[Explanation of symbols]

 1 Inspection pattern 1A Inspection pattern at the start of writing 1B Inspection pattern at the end of writing 2 Reticle pattern 3 Dry plate

Claims (1)

(57) [Claims] At the start and end of reticle pattern drawing, a test pattern (1A) at the start of drawing and a test pattern (1B) at the end of drawing, in which a gap displaced by the placement accuracy on the dry plate is provided therebetween. A pattern accuracy inspection method characterized in that the pattern arrangement accuracy is verified by overlapping drawing and observing the gap.