摘要 |
A method is provided of fabricating a thin film transistor semiconductor film of polycrystalline silicon on a transparent substrate suitable for the manufacture of a liquid crystal display. The deposition of silicon film at very low rates provides conditions for the optimum formation of microcrystallites. As the amorphous silicon is annealed, crystal grains, begun from the seed crystals, are formed in the resulting polycrystalline silicon. The seed crystals help regulate the annealment process, and reduce process dependence on precision deposition and heating methods. This microcrystalline film results in a polycrystalline film having larger crystal grains, and crystal grains of a relatively uniform size. The invention relies on a quantifiable relationship between the pre-melt crystalline fraction and crystallite density, post-melt crystalline fraction and crystallite density, and the ELA density during annealing. An LCD with a TFT polycrystalline film layer over a transparent substrate, formed from annealing substantially amorphous silicon with suspended seed crystals, is also provided.
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