Large polycrystalline silicon grains prepared by excimer laser crystallization of sputtered amorphous silicon film with process temperature at 100°C

Large polycrystalline silicon (poly-Si) grains with a diameter of 1.8 mu m are successfully prepared by excimer laser crystallization (ELC) of a sputtered amorphous silicon (ce-Si) film at a maximum process temperature of 100 degrees C. By pulsed DC magnetron sputtering, ct-Si is deposited on a non-structured oxidized wafer. It is found that the ce-Si film deposited with a bias is easily ablated during ELC, even at an energy density below the super lateral growth (SLG) region. However, the a-Si film deposited without a bias can endure an energy density well beyond the SLG region without ablation. This zero-bias sputtered ce-Si film with a high compressive stress has a low Ar content and a high density, which is beneficial for the suppression of ablation. Large grains with a petal-like shape can be obtained in a wide energy density window, which can be a result from. some fine crystallites in the a-Si matrix. These large grains with a low process temperature are promising for the direct formation of system circuits as well as a high-quality display on a plastic foil.