Method for homogenizing device parameters through photoresist planarization

Abstract

In a fabrication process, photoresist is disposed over a semiconductor substrate (10), covering a front surface (11) of the substrate (10) and filling trenches (12, 14, 16, 18) therein. The photoresist is planarized in chemical mechanical polishing to achieve a uniform thickness throughout the substrate (10). An anisotropic etching process partially removes the photoresist in the trenches (12, 14, 16, 18), thereby creating recesses in the trenches (12, 14, 16, 18). Because the thickness of the photoresist is uniform throughout the substrate (10) before the etching process, the depths of the recesses in different trenches (12, 14, 16, 18) are substantially equal to each other. A uniform recess depth throughout the substrate (10) is thereby achieved. The uniform recess depth facilitates in ensuring the semiconductor devices fabricated on the substrate (10) to have consistent parameters, characteristics, and performances.

Dependencies are inferred from the claim text.