Stepper lens aberration measurement pattern and stepper lens aberration characteristics evaluating method

Abstract

A line-and-space type first pattern and a roughly rectangular second pattern are joined in a rough comb shape to prepare a joint pattern. The first pattern is constituted of a plurality of line patterns each having a width along the direction of its shorter side set to a dimension that does not allow separation/resolution in the field of view of an optical length measuring machine. The second pattern has external dimensions that allow separation/resolution in the field of view of the optical length measuring machine. Such joint patterns are positioned over a distance that allows separation/resolution in the field of view of the optical length measuring machine from each other with the line portions of the first patterns extending outward and achieving a symmetrical positional relationship with together. This pattern is then transferred and formed onto a wafer using a stepper. In the resulting pattern, the outer edges of the line-and-space portions achieve a linear shape, and measurement using the optical length measuring machine is enabled to make it possible to evaluate aberration components. In addition, since the front end of a line-and-space portion undergoes changes in shape sensitively in response to changes in the exposure condition and aberrations, a measurement method with a high degree of sensitivity is achieved.