The Topography Effect on the Lithography Patterning Control for Implatation Layers

Abstract

Lithography patterning is controlled by aerial images and photoresist behaviors. The projected aerial images could be changed by the reflectivity of material and topography. The photoresist process can be affected by baking, development, and local thickness changes. In this paper, we report a study of the optical contribution and the photoresist local/global loading effect from topography, showing a substantial influence on CD (critical dimension) control. Therefore the consideration of photoresist thickness and the refection from underlayers is a must when patterns locate on a complicated topographical environment.