Deposition of stable, low κ and high deposition rate SiF4-doped TEOS fluorinated silicon dioxide (SiOF) films

Fluorine doped silicon dioxide (SiOF) is recognized as a potential intermetal dielectric (IMD) film for sub-half micron devices, due to its low dielectric constant k and good gap-fill capabilities. For the first time, physically stable and high deposition rate (1550 nm/min) SiOF films were deposited using a parallel-plate plasma CVD-single wafer DxZ reactor, involving SiF4/TEOS/O-2 chemistry. The analytical results indicate that these SiOF films, having a F concentration up to 3.0%, contain only Si-F bonding, do not absorb moisture and show stable dielectric constants. A typical highly stable SiOF film has F concentration and dielectric constant values of 2.4% and 3.5, respec tively. This film is thermally stable up to 600 degrees C and can be used as a low cost cap layer for HDP-CVD oxides and other low k spin-on-glass materials, as well as an IMD layer for damascene applications. (C) 1997 Elsevier Science S.A.