LCD device with TFTs in which pixel electrodes are formed in the same plane as the gate electrodes with anodized oxide films and before the deposition of the silicon gate insulator

An active matrix display device, comprising:

• at least one row and at least one column of picture cells provided over a transparent substrate, each picture cell being coupled to a scanning line and a video signal line, and each picture cell including a pixel electrode, a thin film transistor, having drain, source and gate electrodes, and a storage capacitor, said pixel electrode being electrically connected to one of the source and drain electrodes of said thin film transistor and to an electrode corresponding to said storage capacitor, and said video signal line being extended adjacent the other of said source and drain electrodes over spacings between adjacent picture cells in the row direction,
• wherein said thin film transistor is comprised of a gate electrode corresponding to a first conductive layer, a gate insulator provided on said gate electrode, a channel region provided above said gate electrode and including an amorphous silicon layer provided on said gate insulator, and the source and drain electrodes of said thin film transistor are provided at laterally opposing ends of said channel region,
• wherein said pixel electrode is comprised of a second conductive layer,
• wherein said storage capacitor is comprised of a first electrode, a second electrode and a dielectric insulator interposed between the first and second electrodes, and
• wherein the gate insulator of said thin film transistor is formed of a composite insulator layer including a gate surface oxide film, formed by oxidation of said gate electrode, and a silicon nitride film thereon, said gate surface oxide film being formed to cover upper and end side surfaces of said gate electrode and said silicon nitride film being provided on the oxidized upper and end side surfaces of said first conductive layer of said gate electrode and being extended to cover an adjacent end side surface and upper corner surface of said second conductive layer of a corresponding pixel electrode and an adjacent end side surface and upper corner surface of another, second conductive layer corresponding to a pixel electrode of an adjacently disposed picture cell in a row direction, thereby to effect electrical isolation between said gate electrode and the source and drain electrodes of said thin film transistor, between said gate electrode and said corresponding pixel electrode and between said video signal line, which is extended over the gate insulator of a column of picture cells, and both the gate electrode of each said thin film transistor of a corresponding column of picture cells and the second conductive layer corresponding to pixel electrodes of another column of picture cells adjacent thereto.