Semiconductor device including groove portion extending beyond pixel electrode

摘要

A step for forming an island-shaped semiconductor layer of a semiconductor device used in a display device is omitted in order to manufacture the semiconductor device with high productivity and low cost. The semiconductor device is manufactured through four photolithography processes: four steps for forming a gate electrode, for forming a source electrode and a drain electrode, for forming a contact hole, and for forming a pixel electrode. In the step for forming the contact hole, a groove portion in which a semiconductor layer is removed is formed, whereby formation of a parasitic transistor is prevented. An oxide semiconductor is used as a material of the semiconductor layer in which a channel is formed, and an oxide semiconductor having a higher insulating property than the semiconductor layer is provided over the semiconductor layer.

主权项

1. A semiconductor device comprising:
a transistor comprising a gate electrode, a gate insulating layer, a source electrode, a drain electrode, and a semiconductor layer including a first oxide semiconductor; a first wiring electrically connected to the gate electrode; a capacitor wiring; a second wiring electrically connected to the source electrode; a layer including a second oxide semiconductor having a higher insulating property than the semiconductor layer over the second wiring and the semiconductor layer; a pixel electrode electrically connected to the drain electrode; and a groove portion over at least a portion of the first wiring and at least a portion of the capacitor wiring, wherein the semiconductor layer overlaps with the first wiring, the second wiring, the pixel electrode, and the capacitor wiring, and wherein the groove portion extends beyond edges of the pixel electrode along a direction in which the second wiring extends.