Liquid crystal display device with a capacitor and a thin film transistor in a trench for each pixel

Abstract

A liquid crystal display device includes a pair of opposed insulating substrate and a liquid crystal layer sandwiched therebetween. One of the insulating substrates is formed with a first trench for forming a thin film transistor therein and a second trench for forming a capacitor element therein. The thin film transistor is constituted of a semiconductor layer formed along an inner surface of the first trench, a gate insulating layer formed on the semiconductor layer, and a gate electrode formed on the gate insulating layer. The capacitor element is constituted of a first electrode formed along an inner surface of the second trench, a dielectric layer formed on the first electrode, and a second electrode formed on the dielectric layer. The first electrode is formed integrally with the semiconductor layer, thereby increasing an aperture ratio. The first trench has a tapering side surface, thereby ensuring uniform ion implantation for the semiconductor layer. In the case that the substrate has a laminated structure of an insulating substrate and an insulating layer, an etching rate of the substrate as a whole can be improved.

Dependencies are inferred from the claim text.