LIQUID CRYSTAL DISPLAY DEVICE

摘要

PURPOSE:To improve the characteristics of thin-film transistors(TFTs) by forming polycrystalline silicon film to serve as the channel layers of the TFTs, then forming one layer of silicon nitride film by a plasma CVD method thereon. CONSTITUTION:A first insulating film 2 consisting of an HLD film is formed on a transparent glass substrate 1 consisting of quartz. The first polycrystalline silicon film is then formed on the first insulating film 2 and is thereafter patterned to form the polycrystalline silicon films to serve as the channel layers 3. The upper layers of the first polycrystalline silicon films (channel layers 3) are then oxidized to form second insulating films (gate insulating films) 4 consisting of SiO2 films. After the second polycrystalline silicon film is formed thereon, the film is patterned to form gate electrodes 5 on the second insulating films 4. A surface protective film 9 consisting of an Si3N4 film is thereafter formed by a plasma CVD method.