Semiconductor device and method for manufacturing thereof

摘要

An insulating layer is provided with a projecting structural body, and a channel formation region of an oxide semiconductor layer is provided in contact with the projecting structural body, whereby the channel formation region is extended in a three dimensional direction (a direction perpendicular to a substrate). Thus, it is possible to miniaturize a transistor and to extend an effective channel length of the transistor. Further, an upper end corner portion of the projecting structural body, where a top surface and a side surface of the projecting structural body intersect with each other, is curved, and the oxide semiconductor layer is formed to include a crystal having a c-axis perpendicular to the curved surface.

主权项

1. A semiconductor device comprising:
an insulating layer, the insulating layer including a projecting portion; an oxide semiconductor layer over the insulating layer; a gate insulating layer over the oxide semiconductor layer; and a gate electrode over the gate insulating layer, wherein the oxide semiconductor layer faces to a side surface of the projecting portion, a top surface of the projecting portion, and a rounded surface of the projecting portion between the side surface and the top surface, and wherein the oxide semiconductor layer includes a crystal having a c-axis substantially perpendicular to the rounded surface.