Stress in local isolation structures is studied by micro-Raman spectroscopy. The results are correlated with predictions of an analytical model for the stress distribution and with cross-sectional transmission electron microscopy observations. The measurements are performed on structures on which the S&N4 oxidation mask is still present. The influence of the pitch of the periodic local isolation pattern, consisting of parallel lines, the thickness of the mask, and the length of the bird's beak on the stress distribution are studied. It is found that compressive stress is present in the Si substrate under the center of the oxidation mask lines, with a magnitude dependent on the width of the lines. Large tensile stress is concentrated under the bird's beak and is found to increase with decreasing length of the bird's beak and with increasing, thickness of the S&N4 film.

There is a strong interest to use germanium as an active device layer in deep sub-micron devices. This imposes similar stringent material and process requirements for germanium as for silicon. Lattice defect formation during crystal growth and device processing as well as dopant diffusion and activation are to a large extent controlled by the intrinsic point defects in the semiconductor. The properties of the vacancy and the self-interstitial in germanium are, however, not well known. The scarce available experimental data are combined with ab initio and molecular-dynamics calculations and other published simulation results. Based on this a best estimate is made for the formation and migration energies of the vacancy and the self-interstitial in germanium.

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The electrical activity of extended lattice defects formed by interstitial oxygen precipitation in silicon is studied. Their impact on diode characteristics and on minority carrier lifetime is addressed for different initial oxygen contents and pretreatments. The carrier traps present in the substrate are studied with deep level transient spectroscopy and with photoluminescence spectroscopy. The obtained electrical results are correlated with those of structural and chemical characterization using cross-section transmission electron microscopy and Fourier transform infrared spectroscopy.

A simple method for the separation of bulk and surface recombination parameters, based on the simultaneous control of time and amplitude characteristics of carrier concentration decay, is presented. To enhance the precision of the parameter extraction procedure, the amplitude is determined using a wavelength resulting in near surface carrier excitation while the effective lifetime is measured for homogeneous bulk excitation. For the fast interpretation of experimental data, a technique using nomographs of amplitude–decay time correlated dependencies on modulation depth is proposed.