High electron mobility thin InSb films were prepared on mica substrates by conventional vacuum evaporation of InSb to obtain highly sensitive magnetoresistance ( M R ) elements. The 0.15-0.5 p m thick InSb films were prepared in the present work. An optimum evaporation programming pattern was obtained. The crystal properties of these InSb films of 0.2-0.3 p m were investigated using a transmission electron microscope. It was shown that films thinner than 0.2 p m were semitransparent and consisted of [ 11 1 ] oriented single-crystal films. The 0.15-0.3 p m thick InSb films are therefore most useful for low-cost MR elements because of their high element resistance, small temperature coefficient of electron mobility, and high sensitivity.

The crystal growth of InSb thin films on mica substrates was investigated by conventional three temperature vacuum evaporation with varied Sb͞In flux ratios and temperature programming for the substrate. The Sb͞In flux ratio was varied from higher than 1.0 (about 2.0 is optimum), to less than 1.0 (about 0.7 is optimum), to again much higher than 1.0 during the stages of evaporation. The electromagnetic characteristics were investigated and x-ray analysis of the films at various stages was undertaken. The films obtained contained no excess In and they were (111) highly oriented in x-ray analysis, showing high electron mobility. These films were used to prepare high performance Hall elements.

Thin InSb films were prepared on mica substrates by evaporation of InSb to obtain highly sensitive magnetoresistance (MR) elements with high element resistance. The MR effect was investigated for elements with a thickness range of O.lS-O. S f.im. It was observed that only the O.lS-f.im-thick InSb film consists of ap-type, [Ill] -oriented single crystal, while the films thicker than 0.2 f.im show n-type conduction. At room temperature, in a magnetic field of 1 T, the n-type films with thicknesses of 0.2, 0.3, and O.S f.im and length-to-width ratios of 0.12, 0.09, and O.OS, were found to have increasing mobilities of 2.2, 4.4, and S.O m 2 IV s, decreasing element resistances of lIS, 44, and 16 n, and increasing MR(aR IRo) values of 394,652, and 800%.Measurements of the temperature dependence of f.i show that 0.IS-O.3-f.im-thick films have a small temperature coefficient of MR values at room temperature because f.i peaks near that temperature. The 0.IS-O.3-f.im-thick InSb films are therefore most useful for low-cost MR elements because of their high element resistance, small temperature coefficient of electron mobility, and high sensitivity.

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