Method for manufacturing semiconductor device

摘要

To provide a semiconductor device with improved reliability. To provide a semiconductor device with stable characteristics. To provide a transistor having a low off-state current. To provide a transistor having a high on-state current. To provide a novel semiconductor device, a novel electronic device, or the like. A method for manufacturing the semiconductor device includes the steps of forming a first semiconductor over a substrate; forming a second semiconductor over and in contact with the first semiconductor; forming a first layer over the second semiconductor; performing oxygen plasma treatment and then removing the first layer to expose at least part of a surface of the second semiconductor; forming a third semiconductor over and in contact with the second semiconductor; forming a first insulator over and in contact with the third semiconductor; and forming a first conductor over the first insulator.

主权项

1. A method for manufacturing a semiconductor device comprising the steps of:
forming a first oxide semiconductor over a substrate; forming a second oxide semiconductor over and in contact with the first oxide semiconductor; forming a layer over the second oxide semiconductor; performing oxygen plasma treatment after forming the layer; removing the layer so as to expose at least part of the second oxide semiconductor after performing the oxygen plasma treatment; forming a third oxide semiconductor over and in contact with the second oxide semiconductor; forming an insulator over and in contact with the third oxide semiconductor; and forming a conductor over the insulator.