Abstract
The behavior of residue formation during the oxygen-reactive ion etching (RIE) in the multi-layer resist process is studied. The mechanism for the formation of residue and the method used to remove residue are studied. The needle-like residue generated during the under-layer etching process is completely removed by covering the electrode target of the RIE apparatus with polyethylene terephthalate or RIE with O2/CF4 mixture gas. The mechanism for formation of residua is as follows: silicon containing compounds were deposited on the under-layer by spattering of the upper resist and electrode target with oxygen ion generated in O2-RIE process.
