Semiconductor device, manufacturing method of semiconductor device, and display device
A semiconductor device includes a substrate and a channel region which is formed above the substrate by printing, wherein a relationship L≧ 2 a is satisfied where L is a channel length of the channel region and a is a minimum dimension among pattern dimensions and inter-pattern dimensions in the same layer as patterns that define the channel length L; and a relationship W≧ 2 b is satisfied where W is a channel width of the channel region and b is a minimum dimension among pattern dimensions and inter-pattern dimensions in the same layer as a pattern that defines the channel width W.
1. A semiconductor device comprising a substrate and a channel region which is formed above the substrate by printing, wherein:
a relationship L≧ 2 a is satisfied where L is a channel length of the channel region and a is a minimum dimension among pattern dimensions and inter-pattern dimensions in the same layer as patterns that define the channel length L; and
a relationship W≧ 2 b is satisfied where W is a channel width of the channel region and b is a minimum dimension among pattern dimensions and inter-pattern dimensions in the same layer as a pattern that defines the channel width W.
2. The semiconductor device according to claim 1 , wherein each of the minimum dimensions a and b is larger than or equal to 10 μm.
3. The semiconductor device according to claim 2 , wherein a relationship D=L(W+L)c/W(L 2 −c 2 )≦0.1 is satisfied where D is a variation of W/L and c is a processing accuracy value of the patterns that define the channel length L and the pattern that defines the channel width W.
4. The semiconductor device according to claim 3 , wherein the processing accuracy value c is larger than or equal to 2 μm.
5. The semiconductor device according to claim 3 , wherein a relationship D=L(W+L)c/W(L 2 −c 2 )≦0.05 is satisfied.
6. The semiconductor device according to claim 1 , wherein mobility of a semiconductor layer where the channel region is formed is higher than or equal to 0.5 cm 2 /V·s.
7. The semiconductor device according to claim 1 , wherein mobility of a semiconductor layer where the channel region is formed is higher than or equal to 10 cm 2 /V·s.
8. The semiconductor device according to claim 1 , further comprising a gate insulating film formed above the substrate, wherein capacitance of the gate insulating film is smaller than or equal to 10 nF/cm 2 .
9. The semiconductor device according to claim 1 , wherein the semiconductor layer comprises an inorganic oxide.
10. The semiconductor device according to claim 9 , wherein the inorganic oxide comprises at least one of indium, zinc, gallium, tin, and aluminum.
11. The semiconductor device according to claim 9 , further comprising a light absorption layer disposed on a light incidence side of the channel region, for absorbing at least part of light having a wavelength range of 400 nm or less.
12. The semiconductor device according to claim 11 , wherein the light absorption layer also serves as at least one of the substrate and a polarizing plate.
13. A display device comprising the semiconductor device according to claim 1 .
14. A manufacturing method of a semiconductor device comprising a substrate and a channel region which is formed above the substrate by printing, wherein:
a relationship L≧ 2 a is satisfied where L is a channel length of the channel region and a is a minimum dimension among pattern dimensions and inter-pattern dimensions in the same layer as patterns that define the channel length L; and
a relationship W≧ 2 b is satisfied where W is a channel width of the channel region and b is a minimum dimension among pattern dimensions and inter-pattern dimensions in the same layer as a pattern that defines the channel width W.
15. The manufacturing method of a semiconductor device according to claim 14 , wherein at least one of a semiconductor layer where the channel region is formed and the patterns that define the channel length L is formed by ink-jet printing.
16. The manufacturing method of a semiconductor device according to claim 14 , wherein each of the minimum dimensions a and b is larger than or equal to 10 μm.
17. The manufacturing method of a semiconductor device according to claim 16 , wherein a relationship D=L(W+L)c/W(L 2 −c 2 )≦0.1 is satisfied where D is a variation of W/L and c is a processing accuracy value of the patterns that define the channel length L and the pattern that defines the channel width W.
18. The manufacturing method of a semiconductor device according to claim 17 , wherein the processing accuracy value c is larger than or equal to 2 μm and a relationship D=L(W+L)c/W(L 2 −c 2 )≦0.05 is satisfied.
19. The manufacturing method of a semiconductor device according to claim 14 , wherein mobility of a semiconductor layer where the channel region is formed is higher than or equal to 0.5 cm 2 /V·s.
20. The manufacturing method of a semiconductor device according to claim 14 , wherein mobility of a semiconductor layer where the channel region is formed is higher than or equal to 10 cm 2 /V·s.
21. The manufacturing method of a semiconductor device according to claim 14 , wherein a gate insulating film is formed above the substrate so that capacitance of the gate insulating film is smaller than or equal to 10 nF/cm 2 .
22. The manufacturing method of a semiconductor device according to claim 14 , wherein the semiconductor layer comprises an inorganic oxide.
23. The manufacturing method of a semiconductor device according to claim 22 , wherein the inorganic oxide comprises at least one of indium, zinc, gallium, tin, and aluminum.
24. The manufacturing method of a semiconductor device according to claim 22 , wherein a light absorption layer for absorbing at least part of light having a wavelength range of 400 nm or less is formed on a light incidence side of the channel region.
25. The manufacturing method of a semiconductor device according to claim 24 , wherein the light absorption layer also serves as at least one of the substrate and a polarizing plate.