Photodiode and/or PIN diode structures
The present disclosure relates to semiconductor structures and, more particularly, to photodiodes and/or PIN diode structures and methods of manufacture. The structure includes: at least one fin including substrate material, the at least one fin including sidewalls and a top surface; a trench on opposing sides of the at least one fin; a first semiconductor material lining the sidewalls and the top surface of the at least one fin, and a bottom surface of the trench; a photosensitive semiconductor material on the first semiconductor material and at least partially filling the trench; and a third semiconductor material on the photosensitive semiconductor material.
1. A structure, comprising:
at least one fin comprising substrate material, the at least one fin including sidewalls and a top surface;
a trench on opposing sides of the at least one fin;
a first semiconductor material lining the sidewalls and the top surface of the at least one fin, and a bottom surface of the trench;
a photosensitive semiconductor material on the first semiconductor material and at least partially filling the trench;
a third semiconductor material on the photosensitive semiconductor material; and
an isolation structure composed of air or dielectric material within the at least one fin.
2. The structure of claim 1 , wherein the substrate material comprises single crystalline semiconductor material and the at least one fin is provided in a spiral configuration.
3. The structure of claim 1 , wherein the substrate material comprises single crystalline semiconductor material and the at least one fin comprises multiple fins in a concentrically nested shape, each of which are surrounded by multiple trenches.
4. The structure of claim 3 , wherein the multiple fins are alternatively doped of different dopant types.
5. The structure of claim 1 , further comprising a transistor separated from the at least one fin by an isolation structure.
6. The structure of claim 1 , wherein the photosensitive semiconductor material comprises intrinsic semiconductor material.
7. The structure of claim 6 , wherein the intrinsic semiconductor material comprises undoped Ge material.
8. The structure of claim 6 , wherein the substrate material comprises N-type semiconductor material, and the first semiconductor material and the third semiconductor material comprise P-type semiconductor material.
9. The structure of claim 6 , wherein the third semiconductor material is within a trench and on a top surface of the photosensitive semiconductor material, above the at least one fin, to bias operation of an avalanche photodiode.
10. The structure of claim 6 , further comprising an unsilicided semiconductor material on the third semiconductor material, a masking material over the unsilicided semiconductor material, and a contact electrically contacting to the substrate material.
11. The structure of claim 6 , further comprising a silicided semiconductor material on the third semiconductor material, a first contact contacting the silicided semiconductor material, and a second contact electrically contacting to the substrate material.
12. A structure, comprising:
at least one fin of single crystalline semiconductor material;
at least one trench on opposing sides of the at least one fin, the at least one trench having a bottom surface composed of the single crystalline semiconductor material;
a semiconductor material having a first dopant type which lines sidewalls and a top surface of the at least one fin and the bottom surface of the at least one trench;
a photosensitive semiconductor material over the semiconductor material and partially filling the at least one trench;
a second semiconductor material having the first dopant type and which fills a remaining portion of the at least one trench and contacting the photosensitive semiconductor material over the at least one fin; and
an isolation structure composed of air or dielectric material within the at least one fin.
13. The structure of claim 12 , wherein the single crystalline semiconductor material comprises N-type material and the first dopant type comprises P-type material, and the photosensitive semiconductor is an undoped material, different than the single crystalline semiconductor material.
14. The structure of claim 12 , further comprising a silicide contact on the second semiconductor material.
15. The structure of claim 12 , further comprising an unsilicided semiconductor material on the second semiconductor material.
16. The structure of claim 12 , wherein the photosensitive semiconductor material comprises undoped Ge material.
17. The structure of claim 12 , wherein the least one fin of single crystalline semiconductor material is multiple fins in a nested configuration.
18. The structure of claim 12 , wherein the least one fin of single crystalline semiconductor material is in a spiral configuration.
19. A method comprising:
forming at least one fin comprising substrate material with an isolation structure composed of air or dielectric material within the at least one fin;
forming a trench on opposing sides of the at least one fin;
forming a first semiconductor material lining the at least one fin, and a bottom surface of the trench;
forming a photosensitive semiconductor material on the first semiconductor material and at least partially filling the trench; and
forming a third semiconductor material on the photosensitive semiconductor material.