A convenient method to determine stress in thin films deposited on single crystalline silicon wafers is described. The film is treated as an elastic membrane attached to the edges of a thin circular disk. Due to the stress forces of the film, the substrate deforms elastically and assumes a parabolic curvature. This parabolic deflection is determined by measuring the substrate profile on the surface with a light section microscope. Knowing the curvature and the elastic constants of the substrate wafer, one can calculate the stress forces exerted by the film. The experimental accuracy of the method is about ±10%.

The structure, resistivity, and temperature coefficient of resistance (TCR) of Cr-SiO films with controlled compositions from 0 to 50 at. % SiO have been investigated. Randomly disordered films condense at −196 °C. Higher temperatures introduce varying degrees of order accompanied by disproportionation of SiO and reaction with Cr. This leads to nonhomogeneous structures consisting of amorphous SiO2 and Cr–Si phases according to the binary diagram. Metallic particles of α-Cr and Cr3Si, with either little or no long-range order or at the most partially crystalline, provide conductivity which decreases with increasing SiO2 concentration. The resistance decreases during annealing are proportional to the Cr3Si concentration over a wide composition range. The TCR's of highly disordered films are negative and shift toward positive values upon annealing. Their interpretation requires metallic and thermally activated conduction mechanisms in parallel. The resistivity and TCR changes during annealing are attributed to recrystallization and bridging between islands.

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Vacuum evaporation of molybdenum with an electron bombardment source on oxidized silicon wafers produces films whose properties depend on the condensation temperature. At 600°C or above, the films have resistivities comparable to molybdenum wire, satisfactory adhesion, and tolerable stress. They are potentially useful as interconnections for silicon devices and monolithic circuits. All films are polycrystalline with (110) fiber texture. Other crystallite orientations appear above 500°C, while simultaneously the intrinsic film stress becomes decreasingly tensile and, at 625°C, compressive. Film stress and preferred orientation are considered to result from the interaction of lattice defects during the entire growth process and not merely from lattice distortions at the film substrate interface.