The effects of Ti deposition temperature on the resistivity of as-deposited films are reported. The microstructure of as-deposited Ti films and its effect on electrical properties of TiSix formed during subsequent thermal annealing are investigated. Our work shows that the film deposition temperature not only affects the resistivity of as-deposited film but also influences the resistivity of TiSix formed during thermal anneals. The microstructure, specifically the grain size, of as-deposited Ti films appears to be the controlling factor in formation of TiSix phases.

The diffusion of boron from polycrystalline silicon into single crystal silicon has been measured for average boron concentrations in the polysilicon ranging from 1 z 102o to 7 • 1050 atoms/cm ~. Oxygen and carbon contamination levels at the poly/single crystal silicon interface were also measured and were found to be low enough so that the boron diffusion is not affected. The boron concentration, C~ on the single crystal silicon side of the interface is independent of the diffusion time when either boron-implanted or in situ doped polysilicon is used. For highly doped polysilicon films, C~ is also independent of the boron concentration in the polysilicon and in good agreement with the boron solubility in the range from 800 ~ to 1000~ For diffusions at 950~ C~ decreases slightly when the boron concentration in the polysilicon is decreased below 2.5 • 102o atoms/cm 3. However, large changes in the boron penetration depth, xj, in the single crystal were measured for small changes in C~.

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