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A band offset diagram for the heterojunction InyGa1−yPzAs1−z/AlxGa1−xAs based on the transitivity rule and our measured band offset for In0.5Ga0.5P/GaAs is given. A carrier leakage analysis is developed and explains the experimental observations in 670 nm visible InyGa1−yPzAs1−z/AlxGa1−xAs double heterostructure (DH) lasers. The analysis based on the performance of this laser verifies that our band offset is more accurate than previous values. In contrast to GaAs/AlxGa1−xAs, InGaPAs/InP and InGaP/AlGaInP DH lasers, we found that the leakage of holes, rather than of electrons, is responsible for the high threshold current density of this type of laser.

We propose a method to determine the band offset of a heterojunction based on the elimination of the diffusion potential. In0.5Ga0.5P/GaAs heterojunction samples were used for demonstration of this method. As many error sources related to the determination of diffusion potential are avoided in our case, the more accurate value of 137±5 meV has been obtained for the conduction‐band discontinuity.

The effects of x-ray irradiation on the transfer and noise characteristics of excimer-laser-annealed polycrystalline silicon (poly-Si) thin-film transistors (TFTs) have been examined at dose levels up to 1000Gy. Parameters including mobility, threshold voltage, subthreshold swing, and leakage current, as well as flicker and thermal noise coefficients, were determined as a function of dose. In addition, the physical mechanisms of the observed changes in these parameters are analyzed in terms of radiation-generated charge in the gate oxide, at the Si–SiO2 interface, and at the grain boundaries. The results of the studies indicate that poly-Si TFTs exhibit sufficient radiation tolerance for the use in active-matrix flat-panel imagers for most medical x-ray applications.

The generalized formulas have been derived for the curvature radius and layer stresses caused by thermal strain in semiconductor multilayer structure with different elastic moduli and growth temperatures. Several special forms and applications are given.