Lift-Off Process For Small Metal- Metal Spacings
Original Publication Date: 1980-Jan-01
Included in the Prior Art Database: 2005-Feb-12
A metal lift-off process is described which allows smaller metal-to- metal spacings to be used and improves the density of wired circuits. In the conventional two-layer metal lift-off process, the "mushroom" effect, which is an excessive thinning of the top portion of the bottom layer 10, shown in Fig. 1, is a major problem for small metal-to-metal spacings. The mushroom effect is caused by the undercut of the top part of the bottom layer during development and may cause the top layer 12 to be broken off.