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

A process for achieving clean and substantially complete lift-off of a thin film layer formed over a photoresist which is formed above a semiconductor substrate having a surface, said process comprising the steps of:

• (a) forming a thin native oxide layer on said surface of said semiconductor substrate;
• (b) coating said semiconductor substrate having said thin native oxide layer formed thereon with said photoresist;
• (c) baking said photoresist;
• (d) exposing said photoresist to provide a latent pattern in said photoresist;
• (e) developing said photoresist to form a pattern therein using a developer which etches both said photoresist which has been exposed and said thin native oxide layer thereby forming at least one opening in said photoresist and said thin native oxide layer having sides and thereby creating at least one exposed portion of said semiconductor substrate, said developer also removing said thin native oxide layer from beneath said photoresist on said sides of said opening that has not been exposed and undercutting said photoresist on said sides of said opening that has not been exposed thereby forming a reentrant angle in the profile of said photoresist and providing a patterned photoresist;
• (f) depositing a thin film layer on said patterned photoresist and on said exposed portions of said semiconductor substrate;
• and
• (g) lifting-off said photoresist and said thin film layer, thereby forming a pattern in said thin film layer wherein openings in said pattern have smooth sides.