Shaped Siloxane Process
Original Publication Date: 1983-Dec-01
Included in the Prior Art Database: 2005-Feb-08
This article describes a process for reactive ion etching (RIE) structures to produce images having controlled etching slopes. It uses a double-layer resist system wherein the upper layer is profiled to produce the desired etching slope. Double-layer lithographic techniques have been used for high resolution imaging. One prior-art process includes the steps of hard-baking a lower layer of AZ resist, imaging a thin siloxane upper layer and transferring the upper layer image into the lower layer by O2 RIE. The resulted resist structure has vertical sidewalls, and the image transferred into the substrate following the RIE processing step also has vertical sidewalls. However, there are applications which require non-vertical sidewalls, such as structures prior to oxide or metal deposition.