Semiconductor device and method for manufacturing semiconductor device

摘要

A semiconductor device having a transistor including an oxide semiconductor film is disclosed. In the semiconductor device, the oxide semiconductor film is provided along a trench formed in an insulating layer. The trench includes a lower end corner portion and an upper end corner portion having a curved shape with a curvature radius of longer than or equal to 20 nm and shorter than or equal to 60 nm, and the oxide semiconductor film is provided in contact with a bottom surface, the lower end corner portion, the upper end corner portion, and an inner wall surface of the trench. The oxide semiconductor film includes a crystal having a c-axis substantially perpendicular to a surface at least over the upper end corner portion.

主权项

1. A method for manufacturing a semiconductor device comprising steps of:
forming an insulating layer comprising a curved surface; performing a plasma treatment using a rare gas element on the curved surface; forming an oxide semiconductor film over and in contact with the curved surface after the plasma treatment, wherein the curved surface has a curvature radius of longer than or equal to 20 nm and shorter than or equal to 60 nm, wherein the oxide semiconductor film comprises a crystalline region, wherein the crystalline region comprises a plurality of layers of metal atoms, and wherein each of the plurality of layers is formed along the curved surface.