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SiO2 and Si3N4 films have been deposited at low temperatures by a new plasma enhanced evaporation process. The films are stoichiometric and have hydrogen contents below 1 at. %. For the electrical characterization metal–insulator–semiconductor diodes were fabricated and investigated before and after annealing in H2/N2 atmosphere at 430 °C. Ellipsometric and capacitance–voltage measurements yield the dielectric constants which agree well with the theoretical values. From conductance–voltage characteristics the silicon–insulator interface state density Dit was determined. After annealing Dit amounts to 2×1011 eV−1 cm−2 for Si3N4 and to 8×1010 eV−1 cm−2 for SiO2. In addition, the bulk resistivity and the surface resistivity of the deposited films were measured and compared with the values for films grown by conventional high temperature processes.

We report on the first experiments with a composite magnetic bolometer whose mass is 7.5 grams. The thermal pulses produced by single 5.5MeV a-particles have been measured with a SQUID yielding a pulse height of 165 mV at a noise level of 2 mV. Thus, the energy resolution is 65keV and the resolution related to the mass of the detector AElm is 8.7 keVlg. This last number is three orders of magnitude better than with other bolometers. Further developments for detecting neutrinos are pointed out.

Minority carrier mobility is a crucial transport property affecting the performance of semiconductor devices such as solar cells. Compensation of dopant species and novel multicrystalline materials call for accurate knowledge of minority carrier mobility for device simulation and characterization. Yet, measurement techniques of minority carrier mobility are scarce, and published data scatter significantly even on monocrystalline material. In this paper, the determination of minority carrier mobility from self-consistent quasi-steady-state photoluminescence measurements of effective carrier lifetime is presented. The measurement design is distinguished by a limitation of carrier recombination through minority carrier transport—with excess carrier generation and recombination confined to opposite interfaces, respectively. Minority carrier mobility is inferred from the minority carrier diffusion coefficient via the Einstein relation. An experimental proof of concept on monocrystalline p-type material is provided, showing good agreement with state-of-the-art data and models. Considerations for the applicability of the method to compensated and multicrystalline silicon materials are discussed.