Semiconductor device

摘要

An embodiment is a semiconductor device which includes a first oxide semiconductor layer over a substrate having an insulating surface and including a crystalline region formed by growth from a surface of the first oxide semiconductor layer toward an inside; a second oxide semiconductor layer over the first oxide semiconductor layer; a source electrode layer and a drain electrode layer which are in contact with the second oxide semiconductor layer; a gate insulating layer covering the second oxide semiconductor layer, the source electrode layer, and the drain electrode layer; and a gate electrode layer over the gate insulating layer and in a region overlapping with the second oxide semiconductor layer. The second oxide semiconductor layer is a layer including a crystal formed by growth from the crystalline region.

主权项

1. A semiconductor device comprising:
a transistor comprising:
a first gate;a first gate insulating film over the first gate;an oxide semiconductor film over the first gate insulating film;a second gate insulating film over the oxide semiconductor film; anda second gate over the second gate insulating film, wherein the oxide semiconductor film comprises indium and zinc, wherein the oxide semiconductor film comprises a crystalline region, wherein a c-axis of the crystalline region is aligned in a direction perpendicular or substantially perpendicular to a surface of the oxide semiconductor film, wherein the crystalline region comprises:
a first layer comprising indium; anda second layer comprises gallium and does not comprise indium, and wherein the first layer and the second layer are stacked in a direction along the c-axis of the crystalline region.