In order to improve the durability of metal-film magnetic tapes, novel lubricants, A20H, X-1P, and X, a modified phosphazene, were deposited on the tapes. The adhesion, friction, and wear of the unlubricated/lubricated tapes were investigated using an atomic force microscope (AFM). The degradation of the lubricants was studied using a mass spectrometer in high vacuum. The durability of various unlubricated/lubricated tapes was compared in ambient and in humid air. The AFM test results show that the A20H lubricated tape exhibited lower adhesion and friction than X-1P and X lubricated tapes. The lubricants were believed to be mainly degraded by tribochemical reaction and mechanical shear in high vacuum. In high humidity air, the various lubricated tapes exhibit higher friction than in ambient air. By comparing the tribological performances of the various lubricated tapes to metal particle (MP) tape, it was found that the lubricated metal-film tapes exhibit lower adhesion, friction, and wear than the MP tape.

GeTe thin films were prepared by rf diode and magnetron sputtering techniques. Thicknesses from 0.5 to 7 μm were produced. Electron microprobe analysis indicated that the obtained composition of the films produced by the two different systems was Ge51.9Te48.1. As-deposited films were amorphous when deposition was onto a room temperature substrate during sputtering, the electrical conductivity of the amorphous films was increased by several orders of magnitude after crystallization. The amorphous crystalline transformation occurred at 230 °C over a narrow temperature interval of less than 20 °C. This transition was confirmed by measurements of Seebeck coefficient, and electrical conductivity versus temperature. Crystalline films were obtained by (i) furnace annealing, (ii) sputtering at substrate temperature beyond 250 °C, and (iii) laser annealing. The crystalline films had the rhombohedral structure and nonpreferred orientation. Crystalline films obtained by the three different annealing methods exhibited similar properties.

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The effect of prolonged light exposure on photovoltaic quality of glow discharge amorphous silicon films has been studied by the surface photovoltage technique. Two principal results have been observed. (i) The minority-carrier diffusion length degrades but stabilizes at 0.25–0.3 μm. (ii) The space-charge width collapses at open circuit voltage under as little as 0.0001 sun bias illumination. The combination of these two effects suggests that it is gross changes in the built-in electric fields that most seriously degrade the fill factor in amorphous silicon solar cells, rather than changes in μτ.

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