Abstract
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 °C,
around 0.1 µm/min. Etch rate differences between CVD films are much larger than those observed during wet HF etching.
Original language | English |
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Pages (from-to) | D399-D402 |
Journal | Journal of the Electrochemical Society |
Volume | 158 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2011 |
MoE publication type | A1 Journal article-refereed |