Interface layer control methods for semiconductor power devices and semiconductor devices formed thereof
A semiconductor device includes a semiconductor layer structure, a gate insulating pattern on the semiconductor layer structure, a gate electrode on the gate insulating pattern, and an interface layer between the gate insulating pattern and the semiconductor layer structure, the interface layer having a first segment and a second segment with a gap therebetween.
1. A semiconductor device comprising:
a semiconductor layer structure;
a gate insulator on the semiconductor layer structure;
a gate electrode on the gate insulator; and
an interface layer between the gate insulator and the semiconductor layer structure, the interface layer having a first segment and a second segment with a gap therebetween,
wherein the interface layer comprises hydrogen (H), nitrogen (N), boron (B), phosphorous (P), lanthanum (La), strontium (Sr), and/or barium (Ba).
2. The semiconductor device of claim 1 , wherein the first segment of the interface layer extends from an edge of the gate insulator in a direction towards a center portion of the gate insulator.
3. The semiconductor device of claim 2 , wherein a dopant concentration of a portion of the first segment of the interface layer decreases as the first segment extends towards the center portion of the gate insulator.
4. The semiconductor device of claim 2 , wherein a thickness of the gate insulator is greater near the edge of the gate insulator than in the center portion of the gate insulator.
5. The semiconductor device of claim 1 , wherein the first segment and the second segment of the interface layer are substantially coplanar.
6. The semiconductor device of claim 1 , wherein the interface layer further comprises a third segment that is farther from a top surface of the semiconductor layer structure than the first segment or the second segment.
7. The semiconductor device of claim 6 , further comprising a dielectric pattern between the top surface of the semiconductor layer structure and the third segment of the interface layer.
8. The semiconductor device of claim 1 , wherein a portion of the gate electrode extends below a top surface of the semiconductor layer structure.
9. A semiconductor device comprising:
a semiconductor layer structure;
a gate insulator on the semiconductor layer structure;
a gate electrode on the gate insulator; and
an interface layer between the gate insulator and the semiconductor layer structure, the interface layer having a first segment and a second segment with a gap therebetween,
wherein the semiconductor layer structure comprises a first source/drain region, a second source/drain region, and a junction field effect transistor (JFET) region between the first source/drain region and the second source/drain region.
10. The semiconductor device of claim 9 , wherein the gap is over at least a portion of the JFET region.
11. The semiconductor device of claim 9 ,
wherein the first segment is between the first source/drain region and the gate insulator,
wherein the second segment is between the second source/drain region and the gate insulator, and
wherein an upper surface of the semiconductor layer structure between at least a portion of the JFET region and the gate insulator is free of the interface layer.
12. The semiconductor device of claim 11 , wherein the first segment of the interface layer extends towards the JFET region from a first position over the first source/drain region to a second position beyond the first source/drain region that is between the gate insulator and the upper surface of the semiconductor layer structure.
13. The semiconductor device of claim 12 , wherein a dopant concentration of the first segment of the interface layer decreases as the first segment extends towards the second position.
14. The semiconductor device of claim 9 , wherein the interface layer further comprises a third segment on the JFET region that is farther from a top surface of the semiconductor layer structure than the first segment or the second segment.
15. The semiconductor device of claim 14 , further comprising a dielectric pattern between the JFET region and the third segment of the interface layer.
16. A semiconductor device comprising:
a semiconductor layer structure;
a gate insulator on the semiconductor layer structure;
a gate electrode on the gate insulator; and
an interface layer between the gate insulator and the semiconductor layer structure, the interface layer having first and second edge portions on opposite sides of a center portion,
wherein a dopant concentration of the interface layer decreases from the first edge portion to the center portion.
17. The semiconductor device of claim 16 , wherein a first segment of the interface layer extends from the first edge portion of the interface layer in a direction towards the center portion of the interface layer.
18. The semiconductor device of claim 16 , wherein a change in the dopant concentration of the interface layer from the first edge portion to the center portion is linear, exponential, step, and/or random.
19. The semiconductor device of claim 16 , wherein the interface layer comprises a first segment in the first edge portion of the interface layer and a second segment in the second edge portion of the interface layer,
wherein the semiconductor layer structure comprises a first source/drain region, a second source/drain region, and a junction field effect transistor (JFET) region between the first source/drain region and the second source/drain region, and
wherein the semiconductor device further comprises a gap between the first segment and the second segment of the interface layer that is over at least a portion of the JFET region.
20. The semiconductor device of claim 16 , wherein a portion of the gate electrode extends below a top surface of the semiconductor layer structure.
21. The semiconductor device of claim 16 , wherein the interface layer is also present between the gate electrode and the gate insulator.
22. The semiconductor device of claim 16 , wherein a thickness of the gate insulator is greater adjacent an edge of the gate insulator than in a center portion of the gate insulator.
23. The semiconductor device of claim 16 , wherein the semiconductor layer structure comprises a first source/drain region, a second source/drain region, and a junction field effect transistor (JFET) region between the first source/drain region and the second source/drain region.
24. The semiconductor device of claim 16 , wherein the interface layer comprises hydrogen (H), nitrogen (N), boron (B), phosphorous (P), lanthanum (La), strontium (Sr), and/or barium (Ba).
25. The semiconductor device of claim 16 , wherein a portion of the gate electrode extends below a top surface of the semiconductor layer structure.
26. A semiconductor device comprising:
a semiconductor layer structure;
a gate insulator on the semiconductor layer structure;
a gate electrode on the gate insulator; and
an interface layer between the gate insulator and the semiconductor layer structure, the interface layer having a first segment and a second segment with a gap therebetween,
wherein a thickness of the gate insulator is greater near an edge of the gate insulator than in a center portion of the gate insulator.
27. A semiconductor device comprising:
a semiconductor layer structure;
a gate insulator on the semiconductor layer structure;
a gate electrode on the gate insulator; and
an interface layer between the gate insulator and the semiconductor layer structure, the interface layer having a first segment and a second segment with a gap therebetween,
wherein the interface layer further comprises a third segment that is farther from a top surface of the semiconductor layer structure than the first segment or the second segment.
28. A semiconductor device comprising:
a semiconductor layer structure;
a gate insulator on the semiconductor layer structure;
a gate electrode on the gate insulator; and
an interface layer between the gate insulator and the semiconductor layer structure, the interface layer having a first segment and a second segment with a gap therebetween,
wherein a portion of the gate electrode extends below a top surface of the semiconductor layer structure.
29. The semiconductor device of claim 28 , wherein a dopant concentration of a portion of the first segment of the interface layer decreases as the first segment extends towards a center portion of the gate insulator.
30. The semiconductor device of claim 28 , wherein the interface layer comprises hydrogen (H), nitrogen (N), boron (B), phosphorous (P), lanthanum (La), strontium (Sr), and/or barium (Ba).
31. A semiconductor device comprising:
a semiconductor layer structure;
a gate insulator on the semiconductor layer structure;
a gate electrode on the gate insulator; and
an interface layer between the gate insulator and the semiconductor layer structure, the interface layer having a first segment and a second segment with a gap therebetween,
wherein the first segment of the interface layer extends from an edge of the gate insulator in a direction towards a center portion of the gate insulator,
wherein a dopant concentration of a portion of the first segment of the interface layer decreases as the first segment extends towards the center portion of the gate insulator.
32. The semiconductor device of claim 31 , wherein the semiconductor layer structure comprises a first source/drain region, a second source/drain region, and a junction field effect transistor (JFET) region between the first source/drain region and the second source/drain region.
33. The semiconductor device of claim 31 , wherein a portion of the gate electrode extends below a top surface of the semiconductor layer structure.