INFLUENCE OF GROWTH-CONDITIONS ON MORPHOLOGY, COMPOSITION, AND ELECTRICAL-PROPERTIES OF N-SI WIRES

A relationship between growth conditions of silicon wires and their mo rphology, composition, and electroconductivity is presented. In these crystals recently a lattice parameter change and a visible light emiss ion have been found being almost the same as those observed in porous silicon. The crystals were grown by a method of gas-phase reaction in a sealed tube. Using electron microscopy, X-ray microprobe analysis, i on mass spectrometry, Auger electron spectrometry, and temperature dep endencies of electroconductivity, it is shown that the crystals grown in different parts of the tube have various shapes, compositions, and electroconductivities. The study of the grown crystals allows to draw conclusions on the mechanisms of crystal growth and doping, and to fin d a method for controlling these processes. Varying the growth conditi ons, one is able to change (i) shape of crystals (cylindrical or prism atic), (ii) size of crystals in the ranges from 1 mu m to a few cm (ax ial) and from 0.1 to 100 mu m (transverse), (iii) specific electrocond uctivity from a few to 200 Omega(-1) cm(-1) with various degrees of co mpensation.