| 摘要 |
PROBLEM TO BE SOLVED: To develop a three-piece mask process following a four-piece mask process so as to reduce the production cost of a TFT liquid crystal display device. SOLUTION: A step of forming apertures and a step of forming pixel electrodes following the step of forming apertures are carried out with one photomask by forming a source and drain lines from layers of a low resistance metal layer, a passivation insulating layer, an amorphous silicon layer, and a heat-resistant metal layer which can be removed by an etching gas for a gate insulating layer, then adding a passivation insulating layer, forming apertures in the layers of the passivation insulating layer, the amorphous silicon layer and the gate insulating layer by using a photosensitive resin pattern having an inverse tapered cross-sectional form, and lifting off a conductive thin film layer for pixel electrodes to form pixel electrodes. A step of forming an island region of a semiconductor layer is carried out by using halftone exposure techniques during subjecting the first amorphous silicon layer in the aperture to side etching or during forming the above photosensitive resin pattern. Thus, three-piece mask process is achieved. COPYRIGHT: (C)2007,JPO&INPIT |
