Mechanisms of High PSG/SiO2 Selective Etching in a Highly Polymerized Fluorocarbon Plasma
- 1 July 1991
- journal article
- Published by IOP Publishing in Japanese Journal of Applied Physics
- Vol. 30 (7R), 1556-1561
- https://doi.org/10.1143/jjap.30.1556
Abstract
We have investigated high selective etching mechanisms of phosphosilicate glass (PSG) over SiO2 in a highly polymerized fluorocarbon plasma, by studying the Ar+ induced reactions between the adsorption layer and the underlying substrates with X-ray photoelectron spectroscopy. Both of SiO2 and PSG were found to react in a very near surface region, chiefly with the adsorption layer, by reflecting the reactivity in SiO x F y reaction layer below the surface. The mechanisms of the reactivity variance were explained by the difference in density of active sites for unsaturated CF x chemisorption induced by ion bombardment, and the difference of Si-O bond breakability of the underlying substrates. These effects are caused by the existence of P-O or P=O bonds in PSG.Keywords
This publication has 6 references indexed in Scilit:
- Roles of Ions and Radicals in Silicon Oxide EtchingJapanese Journal of Applied Physics, 1990
- Ion-induced etching of SiO2: The influence of mixing and lattice damageJournal of Applied Physics, 1988
- Chemisorption of fluorocarbon free radicals on silicon and SiO2The Journal of Chemical Physics, 1988
- Soft X-ray photoemission study of the silicon-fluorine etching reactionSurface Science, 1986
- Summary Abstract: Mechanisms of polymerization in discharges of fluorocarbonsJournal of Vacuum Science & Technology A, 1985
- A kinetic study of the plasma-etching process. I. A model for the etching of Si and SiO2 in CnFm/H2 and CnFm/O2 plasmasJournal of Applied Physics, 1982