In silicon several electronic levels are known which can be attributed to transition metals. Ignorance persists however about the specific nature of the defect centers. Some progress was made recently on identifying electronic levels from substitutional or interstitial lattice sites and on identifying levels from defect complexes. The sensitive Laplace DLTS technique allows us to determine depth profiles or the influence of the electrical field on the emission rate with unparalleled accuracy. Three examples will be discussed in this short review: The identification of the CoB pair, a reinterpretation of the Ti DLTS spectrum and the complex formation of interstitial Cu with substitutional Cu as the nucleation site.

ZnO (0001) layers on sapphire (0001) substrates were fabricated by means of high temperature high vacuum magnetron sputtering. The layers were deposited onto a thin MgO buffer and a low temperature ZnO nucleation layer, which is a technology commonly used in MBE ZnO growth. This paper reports on using this technology in the sputtering regime.

Single orientation ZnO (00.2) films were deposited by means of high temperature high vacuum reactive magnetron sputtering onto Al 2 O 3 (0001) and GaN (0001) substrates. In order to obtain films of high crystalline quality a novel approach to ZnO sputter deposition was employed, adapting the practice used in MBE technology, of using a MgO buffer layer deposited on sapphire at a high-temperature followed by a ZnO nucleation layer deposited at low temperature. ZnO films were also grown on epitaxial GaN/Al 2 O 3 substrates where the GaN layer was treated as the buffer layer. Following the deposition, all samples were annealed ex-situ in an O 2 flow at 800 o C. The obtained ZnO films have a lattice constant c equal to 5.2036 Å and 5.214 Å for the films deposited on Al 2 O 3 and GaN substrates, respectively. Secondary ion mass spectroscopy depth profiles, scanning and transmission electron microscopy cross sectional images and atomic force microscope were used to characterize the structural properties of the films. Electrical properties were assessed using Hall effect measurement. Photoluminescence spectra were also taken.

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The reported work focuses on developing antidiffusion barriers capable to increase the thermal stability of metal contacts above 700 o C. In the chosen approach, such an antidiffusion barrier consists of several bilayers of materials with different crystalline structures. It has been demonstrated that an interface between such materials effectively blocks the atomic interdiffusion. In this work the following groups of materials were used as the bilayers: ZrB 2 and ZrN and TaSiN and TiN. The materials were deposited by means of room temperature sputtering from elemental and compound targets in inert Ar and reactive Ar+N 2 atmospheres. The structures were characterised using secondary ion mass spectroscopy depth profiling and scanning electron microscopy cross sectional imaging directly after deposition and after degradation. I-V characteristics were measured and contact resistivities were determined from the circular transmission line method.