DEPOSITION OF STABLE, LOW KAPPA-RATE AND HIGH DEPOSITION RATE SIF4-DOPED TEOS FLUORINATED SILICON DIOXIDE (SIOF) FILMS

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