화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.158, No.6, D399-D402, 2011
Correlation Between Film Properties and Anhydrous HF Vapor Etching Behavior of Silicon Oxide Deposited by CVD Methods
The anhydrous HF vapor etching of sacrificial silicon dioxide films grown by plasma-enhanced and low-pressure chemical vapor deposition (PECVD and LPCVD) methods was studied. The film compositions and etch residue were analyzed as part of the study. The effects of the oxide deposition method, precursors, annealing and oxide composition on the etch rate are discussed. Annealing decreases the etch rate and removes water and other hydrogen-containing residue from the films. Films grown using a tetraethoxysilane (TEOS) precursor etch fast, unannealed films even 30 times faster than thermal oxide and they also contain more OH-species than films from SiH4 precursors even after annealing. The etch rate of all CVD films is close to that of thermal oxide after annealing at 1000 degrees C, around 0.1 mu m/min. Etch rate differences between CVD films are much larger than those observed during wet HF etching. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3582318] All rights reserved.