Method for manufacturing semiconductor device
View Patent ↗To provide a method for manufacturing a thin film transistor in which contact resistance between an oxide semiconductor layer and source and drain electrode layers is small, the surfaces of the source and drain electrode layers are subjected to sputtering treatment with plasma and an oxide semiconductor layer containing In, Ga, and Zn is formed successively over the source and drain electrode layers without exposure of the source and drain electrode layers to air.
1. A method for manufacturing a semiconductor device comprising the steps of:
forming source and drain electrode layers over a substrate;
performing a sputtering treatment on surfaces of the source and drain electrode layers;
after performing the sputtering treatment, forming an oxide semiconductor layer over the source and drain electrode layers successively without exposure of the source and drain electrode layers to air;
forming an insulating film over the oxide semiconductor layer; and
forming a gate electrode layer over a channel formation region of the oxide semiconductor layer with the insulating film interposed therebetween.
2. The method for manufacturing a semiconductor device according to claim 1 , wherein the oxide semiconductor layer comprises indium, gallium and zinc.
3. The method for manufacturing a semiconductor device according to claim 1 , wherein the sputtering treatment is performed in an inert gas atmosphere.
4. The method for manufacturing a semiconductor device according to claim 3 , wherein the inert gas atmosphere comprises rare gas.
5. A method for manufacturing a semiconductor device comprising the steps of:
forming source and drain electrode layers over a substrate;
applying a voltage to gas containing an inert gas for producing plasma of the gas;
exposing surfaces of the source and drain electrode layers to the plasma so that the surfaces of the source and drain electrode layers are etched by the plasma; and
after exposing the surfaces of the source and drain electrode layers to the plasma, forming an oxide semiconductor layer over the source and drain electrode layers successively without exposure of the source and drain electrode layers to air.
6. The method for manufacturing a semiconductor device according to claim 5 , wherein the oxide semiconductor layer comprises indium, gallium and zinc.
7. The method for manufacturing a semiconductor device according to claim 5 , wherein the inert gas is rare gas.
8. A method for manufacturing a semiconductor device comprising the steps of:
forming a gate electrode layer over a substrate;
forming an insulating film over the gate electrode layer;
forming source and drain electrode layers, end portions of which overlap with the gate electrode layer with the insulating film interposed therebetween;
applying a voltage to gas containing an inert gas for producing plasma of the gas;
exposing surfaces of the source and drain electrode layers to the plasma so that the surfaces of the source and drain electrode layers are etched by the plasma; and
after exposing the surfaces of the source and drain electrode layers to the plasma, forming an oxide semiconductor layer over the source and drain electrode layers successively without exposure of the source and drain electrode layers to air.
9. The method for manufacturing a semiconductor device according to claim 8 , wherein the oxide semiconductor layer comprises indium, gallium and zinc.
10. The method for manufacturing a semiconductor device according to claim 8 , wherein the inert gas is rare gas.
11. A method for manufacturing a semiconductor device comprising the steps of:
forming source and drain electrode layers over a substrate;
applying a voltage to gas containing an inert gas for producing plasma of the gas;
exposing surfaces of the source and drain electrode layers to the plasma so that the surfaces of the source and drain electrode layers are etched by the plasma;
after exposing the surfaces of the source and drain electrode layers to the plasma, forming an oxide semiconductor layer over the source and drain electrode layers successively without exposure of the source and drain electrode layers to air;
forming an insulating film over the oxide semiconductor layer; and
forming a gate electrode layer over a channel formation region of the oxide semiconductor layer with the insulating film interposed therebetween.
12. The method for manufacturing a semiconductor device according to claim 11 , wherein the oxide semiconductor layer comprises indium, gallium and zinc.
13. The method for manufacturing a semiconductor device according to claim 11 , wherein the inert gas is rare gas.
14. A method for manufacturing a semiconductor device comprising the steps of:
forming source and drain electrode layers over a substrate;
etching surfaces of the source and drain electrode layers; and
after etching the surfaces of the source and drain electrode layers, forming an oxide semiconductor layer over the source and drain electrode layers successively without exposure of the source and drain electrode layers to air.
15. The method for manufacturing a semiconductor device according to claim 14 , wherein the oxide semiconductor layer comprises indium, gallium and zinc.
16. A method for manufacturing a semiconductor device comprising the steps of:
forming a gate electrode layer over a substrate;
forming an insulating film over the gate electrode layer;
forming source and drain electrode layers, end portions of which overlap with the gate electrode layer with the insulating film interposed therebetween;
etching surfaces of the source and drain electrode layers; and
after etching the surfaces of the source and drain electrode layers, forming an oxide semiconductor layer over the source and drain electrode layers successively without exposure of the source and drain electrode layers to air.
17. The method for manufacturing a semiconductor device according to claim 16 , wherein the oxide semiconductor layer comprises indium, gallium and zinc.