1 February 1992 Studies of low-pressure helical resonator discharges for advanced etching
Author Affiliations +
Proceedings Volume 1593, Dry Etch Technology; (1992) https://doi.org/10.1117/12.56929
Event: Microelectronic Processing Integration, 1991, San Jose, CA, United States
Abstract
We have performed diagnostic measurements and polysilicon etching experiments using a halfwave radio frequency helical resonator (HR) source with a 150 mm ? discharge to develop and characterize this technology for low-pressure, high density plasma processing. This discharge source was applied to submicron, anisotropic etching of polysilicon gates using Cl2 and Cl2 /HBr at low pressure (~ 10-3 torr). A solenoidal magnetic field ~60 G along the discharge tube axis enhances plasma density between the source and wafer by a factor of 3–4 to > 1011 cm-3 in a 1000W discharge. In a Cl2/20% HBr feed gas mixture we obtain >3000 Å/min for undoped polysilicon, vertical profiles, and no proximity effects using -10 Vdc additional bias imposed on the wafer. Selectivities for polysilicon over gate oxide and trilevel resist were 50:1 and 4:1, respectively, with no bias during the overetching step.
© (1992) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Dale E. Ibbotson, Dale E. Ibbotson, Chorng Ping Chang, Chorng Ping Chang, } "Studies of low-pressure helical resonator discharges for advanced etching", Proc. SPIE 1593, Dry Etch Technology, (1 February 1992); doi: 10.1117/12.56929; https://doi.org/10.1117/12.56929
PROCEEDINGS
7 PAGES


SHARE
Back to Top