We present a detailed investigation of the influence of oxidation and thinning processes on the in-plane stress in silicon-on-insulator materials. Combining double x-ray diffraction, Fourier transformed infrared and micro-Raman spectroscopy, we show that one can separately evaluate the stress present in the silicon over layer, the buried oxide and the underlying (handle) silicon wafer at any time of a device-forming process.

Due to the large difference in lattice parameters and thermal expansion coefficients, the hetero-epitaxial growth of 3C-SiC on Si mainly results in highly defective layers on strongly bent wafers. The defects may not be detrimental for very basic applications, but the bow is. In order to solve this problem, we have developed a technique called "checker-board" carbonization which, basically, balances a compressive (interfacial) stress by a tensile one. In this way, the overall bending is effectively reduced. In this work, we will report on the effect of polishing the thick, as-grown, 3C-SiC layers deposited on top and results from, both, infrared and Raman spectroscopy collected on 35 mm diameter wafers will be presented. From DDX and low temperature photoluminescence measurements, we will show that a similar 3C-SiC quality can be achieved on, both, parts of the initially compressive and tensile re-grown layers.

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We report on investigation of p-type doped, SiC wafers grown by the Modified- Physical Vapor Transport (M-PVT) method. SIMS measurements give Al concentrations in the range 1018 to 1020 cm-3, with weak Ti concentration but large N compensation. To measure the wafers’ resistivity, carrier concentration and mobility, temperature-dependant Hall effect measurements have been made in the range 100-850 K using the Van der Pauw method. The temperature dependence of the mobility suggests higher Al concentration, and higher compensation, than estimated from SIMS. Additional LTPL measurements show no evidence of additional impurities in the range of investigation, but suggest that the additional compensation may come from an increased concentration of non-radiative centers.

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We have studied the spin-lattice relaxation behaviour of Mn2+ in cubic ZnS at 9 375 MHz between 80 K and 900 K by measuring the line broadening of the |1/2 1/2> → 1/2 - 1/2> transition. This study shows that for high temperatures (T > 273 K) the measured spin-lattice relaxation time T1 varies as T-11 = αT 7 I6 (θD) β[sh2 θ o T]-1. The first term corresponds to a Raman process associated with the acoustical phonons, the second one arises from the optical phonons distribution. The transition probabilities calculation shows that the contributions from the optical and acoustical phonons are similar

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