Photolithography method for forming different pattern density

Abstract

The invention discloses a photolithographic method which is capable of forming different pattern densities and is used for an etching macro load effect test. The photolithographic method uses at least two photolithographic masking plates with different pattern densities, wherein at least one photolithographic masking plate is provided with test patterns. The photolithographic masking plates with different pattern densities are used for carrying out the photolithography at the preset positions in different units in array on a silicon slice, thereby making the array form a photolithographic pattern with even images, and finally the integral photolithographic pattern density is obtained. At least two photolithographic masking plates with different pattern densities are used for carrying out the combined photolithography on basic units, thereby forming the integral photolithographic pattern with different pattern densities, effectively reducing the number of the photolithographic masking plates in the process of the study on the etching macro load, and reducing the study cost.

Description

technical field [0001] The invention relates to a semiconductor photolithography technology, in particular to a photolithography technology for etching macro load effect test. Background technique [0002] The relationship between plasma etching rate and etching area is called loading effect. This effect can be explained theoretically, and can be used as the basis for us to consider the etching mode with fixed time and endpoint detection. In particular, the transmittance characteristics of the photolithography mask determine the size of the exposure area, thus directly causing the loading effects of overall macroloading and local microloading. [0003] In order to fine-tune the etching process parameters to achieve the best process performance, the estimation of the chip exposure area is a key issue; that is, the estimation of the relevant characteristics of the photolithography mask transmittance is necessary. The etching step of the polysilicon layer is a representative ...

AI Technical Summary

Problems solved by technology

In the prior art, in order to obtain photolithographic patterns with different pattern densities, it is often necessary to make multiple photolithographic masks, and the preparation cost is relatively high

At the same time, because the pattern density of the photolithographic mask is discontinuous, there are only a few discontinuous points (see figure 1 ), which is not conducive to the development of research work

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