Methods for determining illumination exposure dosage

Abstract

Semiconductor wafer processing methods are described. In one implementation, a semiconductor wafer is provided with a layer of photoresist thereover. A matrix is defined within the photoresist and comprises a plurality of exposed grating patterns which are formed through successive exposure passes of a mask which defines the grating pattern. The wafer is exposed to conditions which are effective to remove at least some of the photoresist and to clear substantially all of the photoresist over a wafer portion underlying at least one of the exposed grating patterns. The wafer is inspected and at least one processing parameter associated with photoresist which was removed during processing can be ascertained. In a preferred aspect, the processing parameter comprises an illumination exposure dosage. In a preferred implementation, two exposure passes with the mask are made with a second of the passes being shifted by a predetermined amount relative to the grating pattern defined by the first pass. The predetermined amount includes first and second adjustment amounts, with the first adjustment amount being equal to a pitch dimension of the mask, and the second adjustment amount being equal to a value associated with a difference between first and second stepping intervals.