| 摘要 |
PURPOSE:To change a conductivity type from an N<-> type to a P<-> type, and to obtain an enhancement-driven TFT by a simple constitution by forming a BSG film between a poly-Si active layer and an insulating substrate in the N channel TFT and thermally diffusing boron in the BSG film into the poly-Si active layer in a heating process. CONSTITUTION:A BSG film 10 is shaped onto an insulating substrate 9, a poly-Si thin film is deposited onto the BSG film, and a poly-Si active layer 11 is formed through patterning. A thermal oxide film 12 is formed by thermally oxidizing the poly-Si active layer. Since a thermal oxidation process is executed normally at a temperature of 1000 deg.C, boron in the BSG film is thermally diffused into the poly-Si active layer, and a P<-> poly-Si active layer 13 is shaped. Source-drain regions, a gate electrode, a contact electrode, etc., are formed through a normal process, thus manufacturing an N channel TFT. The N channel TFT manufactured in this manner functions as an enhancement type because the active layer is shaped in a P<-> type. |
