Tft, method of making and matrix displays incorporating the tft

Abstract

Improved thin film transistors to reduce defects in the devices incorporating the transistors, including active matrix displays. A first improvement is accomplished by forming a dual insulator layer over the bottom metal layer, which can be the gate line and also the row line in an active matrix display. The first insulator layer is formed by anodizing the metal layer and the second insulator layer is deposited onto the first layer. The dual insulator structure layer can be reanodized to eliminate the effect of pinholes. A second improvement includes providing an interdigitated transistor structure to increase the channel width, minimize internal shorting and minimize the drain capacitance. The interdigitated structure includes at least one source or drain finger formed between at least two drain or source fingers, respectively. A shorted source finger can be disconnected to maintain an operative transistor. A further improvement is provided when forming an active matrix display storage capacitor utilizing the dual insulator layer. A redundant column line can be formed utilizing a second overlying metal layer. A defect masking transistor also can be coupled from each pixel to the previous gate or row line.