A low-temperature in-situ deposition and planarizing phosphosilicate glass process for filling high-aspect-ratio topography

A low-temperature (i.e. 400 degrees C) phosphosilicate glass (PSG) passivation process has been developed that will fill high-aspect-ratio (i.e. 3:1) topography and that can be planarized in situ without a high-temperature (i.e. 800-1100 degrees C) reflow anneal. A tetraethylorthosilicate (TEOS)/ozone chemical vapor deposition (CVD) process, with triethylphosphine (TEP) as the dopant, deposits the PSG. CVD boron oxide (B/sub 2/O/sub 3/) reflows as it is deposited and is used as a sacrificial planarization material. In addition to the high-aspect-ratio fill and in-situ planarization, the PSG process is run as an integrated sequence on a single tool, which optimizes process time and control.<
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