Process for providing clean lift-off of sputtered thin film layers

摘要

A unique photoresist process is provided which achieves clean and complete lift-off of a thin film layer such as a sputtered thin film formed on a photoresist which is formed above a semiconductor substrate. The process of the present invention relies on a reentrant photoresist profile which breaks the continuity of the thin film layer. Accordingly, the process of the present invention ensures a clean lift-off. The desired photoresist profile which breaks the continuity of the thin film layer can be obtained by a typical photoresist process preceded by an oxidation process that takes place on the surface of the semiconductor substrate. The oxidation process provides a thin native oxide layer with thickness ranging from about 30 to 50 . No extra processing steps involving dielectric film deposition and etch are required to achieve clean lift-off. Nevertheless, the process of the present invention ensures the clean lift-off of the thin film layer. Accordingly, the process of the present invention provides good visual and electrical yields.