When a polycrystalline thin film on a substrate is annealed, grooving at gr
ain boundaries will eventually lead to film rupture, followed by island for
mation. Two models were developed to predict the surface roughness at the p
oint of rupture (interface roughening effect included) of polycrystalline t
hin films of TiSi2 on Si based on 2-D and 3-B film analysis. The modeling r
esults predicted that the rms roughness at rupture (RMS*) is essentially Li
near with film thickness (verified For thickness up to 150 nM), and that RM
S* is not sensitive to grain size, 2R (for R = 1-10 mu m). Comparison is ma
de with experimental data obtained with the atomic force microscope from th
ermal stability testing of two TiSi2 thin film specimens on (111)-Si, for a
nnealing treatments carried out at 950 degrees C in argon gas. The two spec
imens had the same thickness of about 150 nm but were formed under differen
t silicide formation schemes. The experimental rms roughness values at rupt
ure were approximately two times higher than predictions of the 3-D film mo
del. The positive deviation is attributed to one or more of the following p
ossibilities: initial film roughness due to intrinsic roughness of the sili
cide grains and presence of film defects like hillocks, faceting and relati
ve subsidence of grains due to anisotropy and grain orientation effects, an
d hole formation and impingement. (C) 1999 Elsevier Science S.A. All rights
reserved.