Patent ID: 7439090

Claim:
A method for manufacturing a lower substrate of a liquid crystal display device, comprising: (A) providing a substrate; (B) forming plural transistors individually comprising a gate, a source, and a drain, wherein the gate is disposed on the substrate, at least one semiconductor layer and at least one gate insulating layer are sandwiched in between the gate and the source/drain, and the drain does not electrically connect to the source; (C) forming on the substrate in sequence a first photosensitive insulating layer and a black matrix, wherein the first insulating layer and the black matrix are the same type of photoresist; (D) patterning the first photosensitive insulating layer and the black matrix to cover the transistor regions, wherein the pattern of the first photosensitive insulating layer is the same as that of the black matrix; (E) forming on the substrate in sequence a second insulating layer and a color filter layer, wherein the second insulating layer and the color filter layer are the same type of photoresist; (F) patterning the second insulating layer and the color filter layer, and simultaneously forming a first contact hole corresponding to the drain, wherein the first contact layer extends through the second insulating layer and the color filter layer so as to expose the part drain; (G) selectively repeating the steps (E) and (F); and (H) forming a patterned transparent electrode layer on the substrate, which electrically connects to the drain.