HEIGHT MAPPER (ZMAP)

Components of optical instruments for use in the semiconductor industry, namely, apparatus comprised of computer software for use in analyzing data received from an overlay metrology tool and overlay targets with corresponding half-shade plates located either above or below the reticle plane, the whole in the same form factor as a standard reticle for use in exposing images on wafers that are used for assessing and adjusting the focus of a lithographic stepper or step and scan tool