Semiconductor device, manufacturing method thereof, and electronic device
A semiconductor device includes a first insulating layer over a substrate, a first metal oxide layer over the first insulating layer, an oxide semiconductor layer over the first metal oxide layer, a second metal oxide layer over the oxide semiconductor layer, a gate insulating layer over the second metal oxide layer, a second insulating layer over the second metal oxide layer, and a gate electrode layer over the gate insulating layer. The gate insulating layer includes a region in contact with a side surface of the gate electrode layer. The second insulating layer includes a region in contact with the gate insulating layer. The oxide semiconductor layer includes first to third regions. The first region includes a region overlapping with the gate electrode layer. The second region, which is between the first and third regions, includes a region overlapping with the gate insulating layer or the second insulating layer. The second and third regions each include a region containing an element N (N is phosphorus, argon, or xenon).
1. A method for manufacturing a semiconductor device comprising the steps of:
forming an insulating layer over an oxide semiconductor layer;
forming a groove in the insulating layer;
forming a conductive film over the insulating layer such that a part of the conductive film is provided in the groove;
forming a gate electrode layer by removing the conductive film partially such that the part of the conductive film remains in the groove;
etching the insulating layer such that at least part of the insulating layer which overlaps the oxide semiconductor layer is removed after forming the gate electrode layer; and
forming a source region and a drain region by adding an ion to the oxide semiconductor layer using the gate electrode layer as a mask after etching the insulating layer.
2. The method for manufacturing a semiconductor device, according to claim 1 ,
wherein phosphorus, argon, or xenon is added as the ion.
3. The method for manufacturing a semiconductor device, according to claim 1 ,
wherein a dose of the ion added is greater than or equal to 1×10 14 ions/cm 2 and less than or equal to 5×10 16 ions/cm 2 .
4. The method for manufacturing a semiconductor device, according to claim 1 ,
wherein the oxide semiconductor layer is formed over a substrate, and
wherein the semiconductor device comprises a region where an angle between a tangent of a side surface of the gate electrode layer and a bottom surface of the substrate is greater than or equal to 60° and less than or equal to 85°.
5. A method for manufacturing a semiconductor device comprising the steps of:
forming an oxide semiconductor layer;
forming a metal oxide film over the oxide semiconductor layer;
forming an insulating layer over the metal oxide film;
forming a groove in the insulating layer;
forming an insulating film over the insulating layer such that a part of the insulating film is provided in the groove;
forming a conductive film over the insulating film such that a part of the conductive film is provided in the groove;
forming a gate electrode layer by removing the conductive film partially and the insulating film such that the part of the conductive film remains in the groove;
removing the insulating layer after forming the gate electrode layer; and
forming a source region and a drain region by adding an ion to the oxide semiconductor layer using the gate electrode layer as a mask after removing the insulating layer.
6. The method for manufacturing a semiconductor device, according to claim 5 ,
wherein phosphorus, argon, or xenon is added as the ion.
7. The method for manufacturing a semiconductor device, according to claim 5 ,
wherein a dose of the ion added is greater than or equal to 1×10 14 ions/cm 2 and less than or equal to 5×10 16 ions/cm 2 .
8. The method for manufacturing a semiconductor device, according to claim 5 ,
wherein the oxide semiconductor layer is formed over a substrate, and
wherein the semiconductor device comprises a region where an angle between a tangent of a side surface of the gate electrode layer and a bottom surface of the substrate is greater than or equal to 60° and less than or equal to 85°.
9. A method for manufacturing a semiconductor device comprising the steps of:
forming an insulating layer over an oxide semiconductor layer;
forming a resist mask by electron beam exposure;
forming a groove in the insulating layer by etching the insulating layer using the resist mask;
forming a conductive film over the insulating layer such that a part of the conductive film is provided in the groove;
forming a gate electrode layer by performing planarization treatment on the conductive film to remove the conductive film partially such that the part of the conductive film remains in the groove;
removing the insulating layer after forming the gate electrode layer; and
forming a source region and a drain region by adding an ion to the oxide semiconductor layer using the gate electrode layer as a mask after removing the insulating layer.
10. The method for manufacturing a semiconductor device, according to claim 9 ,
wherein phosphorus, argon, or xenon is added as the ion.
11. The method for manufacturing a semiconductor device, according to claim 9 ,
wherein a dose of the ion added is greater than or equal to 1×10 14 ions/cm 2 and less than or equal to 5×10 16 ions/cm 2 .
12. The method for manufacturing a semiconductor device, according to claim 9 ,
wherein the oxide semiconductor layer is formed over a substrate, and
wherein the semiconductor device comprises a region where an angle between a tangent of a side surface of the gate electrode layer and a bottom surface of the substrate is greater than or equal to 60° and less than or equal to 85°.