On a substrate, the pattern of the first conductive layer is defined, that is, a gate line combination including gate pads, scanning lines and gate electrodes. A gate insulating layer, a semiconductor layer, a doped semiconductor layer and a second conductive layer are deposited on the substrate and the above-mentioned gate line combination in sequence. A photoresist layer is overlaid on the second conductive layer. The photoresist layer within the aperture areas is fully exposed. Using a half-tone mask or a slit pattern to make parts of the photoresist layer lying on the gate pads and the gate electrodes are not exposed to its full depth. As a result, the photoresist pattern formed varies in thickness. After being processed with drying etching and wet etching for several times, all the layers previously deposited within the aperture areas can be totally etched and removed. However, as regards the layers deposited on the gate pads and the gate electrodes, etching only takes place in those layers above the semiconductor layer. Then, an organic protection layer is laid on the substrate and the above-mentioned structure, and the holes, which are to function as the passageways for the transparent conductive layer to contact the metallic layer, are defined on the organic protection layer. Then, the gate pads are exposed out of holes above them, using dry etching again. Lastly, the pattern of the transparent conductive layer is defined on the organic protection layer and in the plurality of holes.