High speed graphene oxide bolometers and methods for manufacturing the same
Bolometers and methods of forming the same are provided. A bolometer that includes a substrate, a support structure comprising at least one SiGe layer and at least one Si layer, an absorber comprising reduced graphene oxide, and a thermistor comprising partially reduced graphene oxide are described. Also described are methods for forming bolometers and the parts contained therein.
1. A bolometer, comprising:
a substrate;
a support structure comprising at least one SiGe layer and at least one Si layer; and
a bolometer bridge comprising:
an absorber comprising reduced graphene oxide,
an isolation layer, and
a thermistor comprising partially reduced graphene oxide,
wherein the support structure forms an electrical connection between the thermistor and the substrate, and
wherein the support structure provides thermal isolation between the bolometer bridge and the substrate.
2. The bolometer according to claim 1 , further comprising:
another support structure comprising at least one SiGe layer and at least one Si layer disposed between the substrate and the bolometer bridge,
wherein the other support structure forms an electrical connection between the thermistor and the substrate.
3. The bolometer according to claim 2 ,
wherein the support structure includes a plurality of SiGe layers and a plurality of Si layers alternately arranged, and
wherein the other support structures includes another plurality of SiGe layers and another plurality of Si layers alternately arrange.
4. The bolometer according to claim 2 , wherein the SiGe layer is an alloy with a composition between Si 0.8 Ge 0.2 and Si 0.9 Ge 0.1 , inclusive.
5. The bolometer according to claim 1 , wherein a thickness of the absorber is between 20 and 200 nm, inclusive.
6. The bolometer according to claim 1 , wherein a thickness of the thermistor is between 5 and 30 nm, inclusive.
7. The bolometer according to claim 1 , wherein the isolation layer is disposed on the absorber, and the thermistor is disposed on the isolation layer.
8. The bolometer according to claim 7 ,
wherein the isolation layer comprises a dielectric, and
wherein a thickness of the isolation layer is between 2 and 20 nm, inclusive.
9. The bolometer according to claim 1 , wherein the support structure is doped to an n-doping level in a range of 1.0×10 −18 -1.0×10 −20 cm −3 , inclusive.
10. The bolometer according to claim 1 , wherein the thermistor is proximate to the substrate relative to the absorber.
11. The bolometer according to claim 1 , wherein the absorber is proximate to the substrate relative to the thermistor.
12. A method of forming a bolometer, comprising:
forming a plurality of SiGe layers and Si layers on a substrate that includes a mirror, wherein the plurality of SiGe layers and Si layers are alternately arranged;
etching the plurality of SiGe layers and Si layers to form a plurality of support structures;
forming a sacrificial layer around the plurality of support structures, wherein a surface of the sacrificial layer and at least one surface of each support structure lie approximately in the same plane;
providing a bolometer bridge, that includes a thermistor comprising partially reduced graphene oxide, an absorber comprising reduced graphene oxide, and an isolation layer, on the surface of the sacrificial layer and the at least one surfaces of the support structures; and
removing the sacrificial layer such that the bolometer bridge is supported by the support structures.
13. The method according to claim 12 , wherein the plurality of support structures form an electrical connection between the thermistor and the substrate.
14. The method according to claim 12 , wherein the plurality of SiGe layers are alloys with a composition between Si 0.8 Ge 0.2 and Si 0.9 Ge 0.1 , inclusive.
15. The method according to claim 12 , wherein a thickness of the absorber is 20 to 200 nm, inclusive.
16. The method according to claim 12 , wherein a thickness of the thermistor is between 5 and 30 nm, inclusive.
17. The method according to claim 12 , wherein the isolation layer is disposed on the absorber, and the thermistor is disposed on the isolation layer.
18. The method according to claim 12 , wherein the isolation layer comprises a dielectric, and wherein a thickness of the isolation layer is 2 to 20 nm, inclusive.
19. The method according to claim 12 , wherein the bolometer bridge is provided such that the thermistor is proximate to the substrate relative to the absorber.
20. The method according to claim 12 , wherein the bolometer bridge is provided such that the thermistor is proximate to the substrate relative to the thermistor.