Water diffusivity of dielectric films evaluated with use of D2O

Diffusion coefficients of D2O in dielectric films are studied through the analysis of deuterium depth profiles by secondary ion mass spectrometry (SIMS). The films investigated are atmospheric chemical vapor deposition (CVD) SiO2 (LTO), borophosphosilicate glass (BPSG), plasma-CVD SiO2, tetra-ethoxy-silicate (TEOS)-based plasma-enhanced CVD SiO2 (P-TEOS), O3- and TEOS-based SiO2 ( O3-TEOS), and organic spin-on glass (SOG) films. The diffusion coefficient of D2O in the plasma-CVD SiO2 film is less than one-fifth those in the other films.