Patent ID: 7968357

Claim:
A manufacturing method of a liquid crystal display device comprising the steps of: forming a thin film transistor having a first electrode thereof connected to a video signal line and a second electrode on a substrate; forming a first silicon nitride film above the second electrode; forming an organic insulation film above the first silicon nitride film; forming a capacitance electrode above the organic insulation film; forming a second silicon nitride film above the capacitance electrode; forming a contact hole on the second electrode; forming a pixel electrode on the second silicon nitride film; wherein the second silicon nitride film is formed at a temperature lower than a forming temperature of the first silicon nitride film, the contact hole is formed by etching both of the first silicon nitride film and the second silicon nitride film collectively by dry etching, the second electrode and the pixel electrode are connected to each other via the contact hole, a potential different from a potential applied to the pixel electrode is applied to the capacitance electrode, and a holding capacitance is formed by the pixel electrode, the second silicon nitride film and the capacitance electrode.