Shallow trench textured regions and associated methods
Photosensitive devices and associated methods are provided. In one aspect, for example, a photosensitive imager device can include a semiconductor layer having multiple doped regions forming a least one junction, a textured region coupled to the semiconductor layer and positioned to interact with electromagnetic radiation. The textured region can be formed from a series of shallow trench isolation features.
1. An optoelectronic device having enhanced absorption of electromagnetic radiation, comprising:
a semiconductor layer having a light incident side and an opposed side, said semiconductor layer having multiple doped regions forming at least one junction,
a textured region comprising a plurality of shallow trench isolation surface features located on the light incident side of the semiconductor layer and configured to interact with incident electromagnetic radiation,
a support substrate coupled to said semiconductor layer, and
a first bonding layer disposed between the semiconductor layer and the support substrate,
wherein said optoelectronic device is a photosensitive imager device capable of detecting visible and infrared electromagnetic radiation.
2. The device of claim 1 , wherein the semiconductor layer is single crystal silicon.
3. The device of claim 1 , wherein the shallow trench isolation surface features are formed in the semiconductor layer.
4. The device of claim 1 , wherein the shallow trench isolation surface features have a substantially uniform height.
5. The device of claim 1 , wherein the shallow trench isolation surface features are not uniform in height.
6. The device of claim 1 , further comprising a device layer coupled to the semiconductor layer on said side opposed to the light incident side.
7. The device of claim 1 , wherein said first bonding layer comprises any of silicon oxide, silicon nitride and amorphous silicon.
8. The device of claim 1 , wherein said semiconductor layer has a thickness in a range of about 1 micron to about 10 microns.
9. The device of claim 1 , wherein said bonding layer has a thickness in a range of about 30 nm to about 3 microns.
10. The device of claim 1 , wherein said bonding layer has a thickness in a range of about 40 nm to about 2 microns.
11. The device of claim 1 , wherein said plurality of shallow trench isolation surface features have a height in a range of about 50 nm to about 20 microns.
12. The device of claim 1 , wherein said shallow trench isolation surface features comprise pyramids.
13. The device of claim 1 , wherein said plurality of shallow trench isolation surface features are formed by using a patterned mask and photolithography followed by etching.
14. The device of claim 1 , wherein said plurality of shallow trench isolation surface features comprise multiple etched levels.
15. The device of claim 1 , wherein said textured region enhances absorption of electromagnetic radiation within said semiconductor layer.
16. The device of claim 1 , wherein said textured region increases optical absorption of the semiconductor layer over an electromagnetic spectrum range of at least about 700 nm to about 1100 nm.
17. The device of claim 1 , wherein said textured region increases effective optical path length of light as it passes through the semiconductor layer.
18. The device of claim 1 , wherein said textured region allows the semiconductor layer to experience multiple passes of light.
19. The device of claim 1 , further comprising a second bonding layer positioned between the first bonding layer and the support substrate.
20. The device of claim 19 , further comprising a reflector layer disposed between the first bonding layer and the second bonding layer.
21. The device of claim 1 , wherein the shallow trench isolation surface features are arranged according to a pattern.
22. The device of claim 21 , wherein the pattern is an at least substantially uniform grid.
23. The device of claim 21 , wherein the pattern is a non-uniform arrangement.
24. A method of making an optoelectronic device, comprising:
bonding a semiconductor layer to a support substrate, wherein bonding the semiconductor layer to the support substrate includes:
depositing a first bonding layer onto the semiconductor layer; and
bonding the first bonding layer to a second bonding layer disposed on the support substrate; and
creating a plurality of shallow trench isolation surface features on a light incident side of said semiconductor layer.
25. The method of claim 24 , wherein the step of creating the plurality of shallow trench isolation surface features comprises generating an array of surface features using shallow trench isolation etching.
26. The device of claim 1 , further comprising deep trench isolation for isolating the device.
27. The device of claim 26 , wherein said deep trench isolation provides light trapping functionality.
28. An optoelectronic device having enhanced absorption of electromagnetic radiation, comprising:
a semiconductor layer having a light incident side and an opposed side, said semiconductor layer having multiple doped regions forming at least one junction,
a textured region comprising a plurality of shallow trench isolation surface features located on the light incident side of the semiconductor layer and configured to interact with incident electromagnetic radiation,
a support substrate coupled to said semiconductor layer, and
a first bonding layer disposed between the semiconductor layer and the support substrate,
a second bonding layer positioned between the first bonding layer and the support substrate, and
a reflector layer disposed between the first bonding layer and the second bonding layer.
29. The device of claim 28 , wherein said shallow trench isolation surface features comprise pyramids.
30. The device of claim 28 , wherein said plurality of shallow trench isolation surface features are formed by using a patterned mask and photolithography followed by etching.
31. The device of claim 28 , wherein said semiconductor layer has a thickness in a range of about 1 micron to about 10 microns.
32. The device of claim 28 , wherein the shallow trench isolation surface features have a substantially uniform height.
33. The device of claim 28 , wherein the shallow trench isolation surface features are not uniform in height.
34. The device of claim 28 , wherein said plurality of shallow trench isolation surface features have a height in a range of about 50 nm to about 20 microns.
35. The device of claim 28 , wherein said photosensitive imager device is capable of detecting visible and infrared electromagnetic radiation.
36. The device of claim 28 , wherein said textured region enhances absorption of electromagnetic radiation within said semiconductor layer.
37. The device of claim 28 , wherein said textured region increases optical absorption of the semiconductor layer over an electromagnetic spectrum range of at least about 700 nm to about 1100 nm.
38. The device of claim 28 , wherein said textured region increases effective optical path length of light as it passes through the semiconductor layer.
39. The device of claim 28 , wherein said textured region allows the semiconductor layer to experience multiple passes of light.
40. The device of claim 28 , further comprising deep trench isolation for isolating the device.
41. The device of claim 40 , wherein said deep trench isolation provides light trapping functionality.
42. The device of claim 28 , wherein the shallow trench isolation surface features are arranged according to a pattern.
43. The device of claim 42 , wherein the pattern is an at least substantially uniform grid.
44. The device of claim 42 , wherein the pattern is a non-uniform arrangement.