SPROUT is a computer program for the rational design of molecules for a range of applications in molecular recognition. Molecular graphs are built in a stepwise fashion by subgraph addition. Several heuristics are being explored to restrict the combinatorial explosion that is inherent in structure generation. These include the use of generalized molecular fragments, called templates, as building blocks. Structure generation consists of two stages: (i) the generation of skeletons from templates that satisfy steric constraints and (ii) the substitution of heteroatoms into skeletons to produce molecules that satisfy other constraints such as electrostatics. The choice and definition of the templates and template joining rules are described together with a description of the atom substitution process.

This new chapter of the PhD thesis was an addition to the presented already material at TU Sofia, Bulgaria. This was necessary to obtain the permission to prepare the thesis for its final version. Unfortunatelly this thesis was never presented but it served for the core to the presented in IST, Portugal, later on.

The aim of this work is to provide the basis for the interpretation, under steady state, of the lateral photoeffect in p-i-n a-Si:H 1D Thin Film Position Sensitive Detectors (1D TFPSD) through an analytical model. The experimental data recorded in 1D TFPSD devices with different performances are compared with the predicted curves and the obtained correlation's discussed.

The introduction into a traditional p.i.n. structure of two defective buffer layers near the p/i and i/n interfaces can improve the device stability and efficiency through an enhancement of the electric field profile at the interfaces and a reduction of the available recombination bulk centers. The defectous layer (`i-layer'), grown at a higher power density, present a high density of the defects and acts as `gettering centers' able to tailor light induced defects under degradation conditions. If the i-layer density of states remains below 1016 eV-1 cm-3 and assuming a Gaussian distribution of defect states, the gettering center distribution will not affect significantly the carrier population but only its spatial distribution. We report here about a device numerical simulation that allows us to analyze the influence of the `i- layer' position, thickness and density of states on the a-Si:H solar cells performances. Results of some systematic simulation rom the ASCA program (Amorphous Solar Cell Analysis), and for different configurations will be presented.

The aim of this work is to provide the basis for the interpretation of the lateral photoeffect in p-i-n a-Si:H one-dimensional thin-film position-sensitive detectors (1D TFPSDs) under steady state, through an analytical model. The experimental data recorded in 1D TFPSD devices with different characteristics are compared with the predicted curves and the obtained correlations are discussed. © 1996.

This work presents experimental data concerning the role of the oxygen partial pressure used during the preparation process, on the structure, composition and optoelectronic properties of wide band gap doped microcrystalline silicon oxycarbide films produced by a TCDDC system [1].

Tin doped indium oxide (ITO) films were deposited on glass substrates by rf reactive magnetron sputtering using a metallic alloy target (In-Sn, 90-10). The post-deposition annealing has been done for ITO films in air and the effect of annealing temperature on the electrical, optical and structural properties of ITO films was studied. It has been found that the increase of the annealing temperature will improve the film electrical properties. The resistivity of as-deposited film is about 1.3×10-1 Ω* cm and decreases down to 6.9×10-3 Ω* cm as the annealing temperature is increased up to 500°C. In addition, the annealing will also increase the film surface roughness which can improve the efficiency of amorphous silicon solar cells by increasing the amount of light trapping.

Tin doped indium oxide (ITO) films were deposited on glass substrates by rf reactive magnetron sputtering using a metallic alloy target (In-Sn, 90-10). The post-deposition annealing has been done for ITO films in air and the effect of annealing temperature on the electrical, optical and structural properties of ITO films was studied. It has been found that the increase of the annealing temperature will improve the film electrical properties. The resistivity of as deposited film is about 1.3 × 10-1 gW*cm and decreases down to 6.9 × 10-3 Ω*cm as the annealing temperature is increased up to 500 °C. In addition, the annealing will also increase the film surface roughness which can improve the efficiency of amorphous silicon solar cells by increasing the amount of light trapping. © 1995.

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Silicon oxycarbide microcrystallinc layers, n- and p-doped, highly conductive and highly transparent have been produced using a Two Consecutive Decomposition and Deposition Chamber (TCDDC) system. The films exhibit suitable properties for optoelectronic applications where wide band gap materials with required conductivity and stability are needed. In this paper we present the role of partial oxygen pressure (po2) in controlling the composition, structure and transport properties (conductivity. δd and optical gap, Eop) of silicon oxycarbide microcrystalline layers. © 1994 Materials Research Society.

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