Transistor, semiconductor device, and electronic device
摘要
說明書
The electrode 105_1 includes, in the channel length direction, a region overlapping with the electrode 110_1a, a region overlapping with the electrode 110_1b, and a region overlapping with the channel formation region of the semiconductor layer 109_1b.
To reduce the parasitic capacitance between the wiring 118_1 and the electrode 112_1 and to increase the withstand voltage therebetween, for example, the thickness of the insulating layer 104 is preferably increased. Similarly, the thickness (height) of the electrode 105_1 is preferably increased. However, if the insulating layer 104 is too thick, the productivity of the transistor might be lowered. Similarly, if the electrode 105_1 is too thick (too high), the productivity of the transistor might be lowered. The thickness of the insulating layer 104 is preferably greater than or equal to the thickness of the insulating layer 108 and less than or equal to five times the thickness of the insulating layer 108. Similarly, the thickness of the electrode 105_1 is preferably greater than or equal to the thickness of the insulating layer 108 and less than or equal to five times the thickness of the insulating layer 108. The amount of excess oxygen contained in the insulating layer 104 can be increased by increasing the thickness of the insulating layer 104. Excess oxygen is described later.
