Patent ID: 7251016
Filing Date: 2007-07-31
Classification: G03F

Abstract:
1. A method for the correction of structure size dependent positioning errors during the photolithographic projection by an exposure apparatus, the method comprising: providing an exposure apparatus for performing an exposure in a plurality of exposure fields; providing a simulation model of the exposure apparatus with a calculation specification for specifying correction values for intra-field errors during the exposure; providing a first pattern including a plurality of first structure elements and a plurality of first measurement marks; photolithographically projecting the first pattern by the exposure apparatus into the exposure fields, different positioning errors being brought about for the first structure elements and first measurement marks due to different dimensions as a result of aberration, the first structure elements being beset by a first positioning error depending on the dimensions of the first structure elements and the position of the first structure elements in the exposure field, the first measurement marks being beset by a second positioning error depending on the dimensions of the first measurement marks and the position of the first measurement marks in the exposure field; providing a correction function for specifying the first positioning error and the second positioning error; determining an average relative positioning error from the first positioning error and the second positioning error; calculating correction values for the control of the exposure apparatus based on the first positioning error and the second positioning error by the simulation model; and transmitting the correction values as an intra-field correction to the exposure apparatus so that subsequent exposures are performed with an improved overlay.