14 May 2004 Inorganic Bi/In thermal resist as a high-etch-ratio patterning layer for CF4/CHF3/O2 plasma etch
Author Affiliations +
Abstract
Bimetallic thin films containing indium and with low eutectic points, such as Bi/In, have been found to form highly sensitive thermal resists. They can be exposed by lasers with a wide range of wavelengths and be developed by diluted RCA2 solutions. The exposed bimetallic resist Bi/In can work as an etch masking layer for alkaline-based (KOH, TMAH and EDP) “wet” Si anisotropic etching. Current research shows that it can also act as a patterning and masking layer for Si and SiO2 plasma “dry” etch using CF4/CHF3. The profile of etched structures can be tuned by adding CHF3 and other gases such as Ar, and by changing the CF4/CHF3 ratio. Depending on the fluorocarbon plasma etching recipe the etch rate of laser exposed Bi/In can be as low as 0.1nm/min, 500 times lower than organic photoresists. O2 plasma ashing has little etching effect on exposed Bi/In, indicating that laser exposure is an oxidation process. Experiment result shows that single metal Indium film and bilayer Sn/In exhibit thermal resist characteristics but at higher exposure levels. They can be developed in diluted RCA2 solution and used as etch mask layers for Si anisotropic etch and plasma etch.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Yuqiang Tu, Yuqiang Tu, Glenn H. Chapman, Glenn H. Chapman, Jun Peng, Jun Peng, } "Inorganic Bi/In thermal resist as a high-etch-ratio patterning layer for CF4/CHF3/O2 plasma etch", Proc. SPIE 5376, Advances in Resist Technology and Processing XXI, (14 May 2004); doi: 10.1117/12.536193; https://doi.org/10.1117/12.536193
PROCEEDINGS
12 PAGES


SHARE
RELATED CONTENT


Back to Top