Metal-induced low temperature (≤ 550°C) crystallization of a-Si_(1-x)Ge_x (0≤x≤1) layers on SiO_2 films has been investigated. For low Ge fractions below 20 %, Ge-doping enhanced plane growth was observed. This realized strain-free poly-Si_(0.8)Ge_(0.2) films with large grains (18μm). On the other hand, dendrite growth was dominant for intermediate Ge fractions with 40-60 %. Directions and widths of dendrites became straight and narrow with decreasing annealing temperature. As a result, very sharp needlelike crystals (width: 0.05μm, length: 10 μm) were obtained at the optimized growth conditions (x: 0.4, annealing: 450°C, 20 h). These new polycrystalline SiGe films on insulators should be used for the advanced system-in-displays and novel one-dimensional wires.
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