Ternary W-Si-N thin films have been reactively sputter-deposited from a
W5Si3 target at different nitrogen partial pressures. The composition has
been determined by 2.2 MeV4He+ beam, the structure by
x-ray diffraction and transmission electron microscope, the chemical bonds
by Fourier transform - infrared spectroscopy and the surface morphology by
scanning electron microscopy. Electrical resistivity was measured by four
point probe technique on the as grown films. The film as-deposited is
amorphous with the Si/W ratio increasing from about 0.1 up to 0.55 with the
nitrogen content going from 0 to 60 at%. The heat treatments up to 980 °C
induce a loss of nitrogen in the nitrogen rich samples. Segregation of
metallic tungsten occurs in the sample with low nitrogen content
(W58Si21N21). Samples with high nitrogen
content preserve the amorphous structure, despite of the precipitation of a
more ordered phase inferred by FT-IR absorbance spectrum of the layer
treated at highest temperature. The surface morphology depends upon the
nitrogen content; the loss of nitrogen induces the formation of blistering
and in the most nitrogen rich sample the formation of holes. Electrical
resistivity preliminary results on the as grown layers range between 500 and
4750 μωcm passing from the lowest to the highest N concentration.