Patent ID: 6574524
Filing Date: 2003-06-03
Classification: G03F,H01L

Abstract:
A method of exposing the dies of a wafer using photolithography, said method comprising steps of:positioning a sample wafer on a wafer stage operatively associated with an exposure device of photolithography equipment; moving the stage with the sample wafer thereon by predetermined increments, based on known characteristics of the dies of the sample wafer, to move each of the dies of the sample wafer sequentially to an initial aligned position relative to the exposure device; inspecting the sample wafer for any deviation between the initial aligned position and an ideal position of alignment for each of the dies of the sample wafer, and generating raw data representative of said deviation for each die of the sample wafer; mapping the raw data to correlate the deviations to the areas on the sample wafer where the deviations occur, and storing the mapped data as processed data; forming a preliminary job file on the basis of at least the processed data, and using the preliminary job file to establish a basic setting of the exposure device that defines initial operating parameters of the exposure device, and which parameters cause the exposure device to perform an overall alignment correction operation in which an initial alignment of the sample wafer relative to the exposure device is set prior to the exposure of the dies; from the stored data, generating a correction deviation value for each of the dies of the sample wafer except for those dies that will be positioned at the ideal position of alignment under the basic setting of the exposure device established by the preliminary job file; on the basis of the correction deviation values for the dies, forming a final job file by which the exposure equipment will operate after the basic setting of the exposure device is established; and sequentially moving the dies of the sample wafer to an exposure position at which the dies are aligned relative to the exposure device, and exposing each of the dies to an image borne by the exposure device once the die is at the exposure position, all under the direction of the final job file, whereby said deviation is minimized for each of the dies.