New Approach to Solve the Contact Step Coverage Problem by Using Lift-Off Technique
Original Publication Date: 1985-Mar-01
Included in the Prior Art Database: 2005-Feb-18
This article relates to methods for fabricating integrated circuits and more particularly to a method for improving contact hole step coverage. Still more particularly, it relates to a method for improving contact hole step coverage using lift-off techniques. In the current VLSI technology, it is clear that anisotropic etching for contact hole or interconnect via openings is needed to control feature size and undercutting. The first and most obvious consequence of an anisotropically-etched contact hole is that the lack of a contoured profile may result in thinner metal deposition at sharp edges (Fig. 1) which may cause higher resistance, excess heating, electrical defects, electromigration problems and less reliable device operation. Referring to Fig.