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The characteristics of various frequency-change force sensors were analyzed using the finite-element method and compared. In the case of the sensor design, displacements at both ends of the sensor must be made as small as possible to reduce the influence of fixation, and the resonance frequency of the sensor must be considerably changed by the axial force to realize high sensitivity. The displacements u i (i ¼ x; y; z) were analyzed as the ratio u i =u i0 to the maximum displacement u i0 at the central part of the long arm of the sensor, and then the sensor structure with the ratio u i =u i0 , which is less than 10 À3 , was clarified. In addition, the change Á f of the resonance frequency f 0 by the axial force was analyzed. The force sensor with a flat and simple structure, which is preferable as a micro electro mechanical system (MEMS) sensor, was shown to be best from the standpoint of high sensitivity and small displacements.

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Growth by molecular beam epitaxy and characterisation of unintentionally doped Ga1-x InxSb layers in the full compositional range on GaAs substrates are reported. The grown samples were characterised by reflection high-energy electron diffraction, X-ray diffraction and Hall-effect measurements. The layers had carrier concentrations below 6 × 1016 \kubik with a maximum at x ≈0.5, where the conduction switched from p-type to n-type. Temperature-dependent Hall-effect measurements together with mixed-conduction simulations showed that the n-type behaviour is caused by intrinsic electrons and the large electron-hole ratio rather than donor centres.