Effects of germanium composition on performance of continuous-wave laser lateral crystallization n-channel polycrystalline silicon-germanium thin-film transistors on glass substrate

In this study, the electrical properties of continuous-wave laser lateral crystallization polycrystalline silicon-germanium (poly- $\mathrm{Si}_{1-\mathrm{x}} \mathrm{Ge}_{\mathrm{x}}; \mathrm{x} = 0-0.3$ ) thin films were evaluated using Hall effects and thin-film transistors (TFTs). The thin films included large grains, with lengths exceeding 100 µm for x = 0.1 and 0.3. With increasing Ge content, the TFTs exhibited reduced field-effect mobility, a positive threshold voltage shift, and an increased subthreshold swing. Furthermore, the Hall effects yielded an increased hole concentration and reduced mobility with Ge concentration. The variable TFT performance is attributable to the generation of acceptors, which may be contributed by the dangling bond in the zig-zag Σ 3 coincident site lattice.