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The interpretation of experimental results concerning insulator-semiconductor interface states in metal-insulator-semiconductor structures obtained with the deep-level transient spectroscopy (DLTS) techniques, particularly in the case of high-density interface states continuously distributed in the energy band gap (larger than 5×1011 eV−1 cm−2), is reconsidered. It is shown that the ‘‘saturating pulse’’ condition, which allows a classical treatment of the DLTS spectra, corresponds to a filling pulse amplitude which rapidly increases with the average density of the traps located at the interface. The use of large or small pulses is discussed. The determination of the profile of interface state density Nss(E) can only be derived for high densities from a simulation of the DLTS signal ΔC(T), since the classical relation between Nss and ΔC is no more valid in this case. A simplified simulation is proposed. It allows us to justify the results reported in this paper and to fit experimental results previously obtained on Al–Si3N4–GaAs structures with interface state densities about 1013 eV−1 cm−2.

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In this paper we present a method to compute the scattering states of holes in spherical bands in the strong spin-orbit coupling regime. More precisely, we calculate scattering phase shifts and amplitudes of holes induced by defects in a semiconductor crystal. We follow a previous work done on this topic by Ralph ͓Philips Res. Rep. 32, 160 ͑1977͔͒ to account for the p-wave nature and the coupling of valence-band states. We extend Ralph's analysis to incorporate finite-range potentials in the scattering problem. We find that the variable phase method provides a very convenient framework for our purposes and show in detail how scattering amplitudes and phase shifts are obtained. The Green's matrix of the Schrödinger equation, the Lippmann-Schwinger equation, and the Born approximation are also discussed. Examples are provided to illustrate our calculations with Yukawa-type potentials.