Fabrication of photodiode array on spherical platform for 4-PI detection awareness

1. A method for fabricating an array of sensors on an object having a non-developable surface, comprising:

growing an epitaxial structure on a substrate;

bonding, without the use of an adhesive, the epitaxial structure to a flexible membrane to form a device structure;

forming, from the epitaxial structure of the device structure, an array of sensors using photolithographic techniques;

cutting the device structure into segments, where shape of the segments depends on shape of the non-developable surface of a target object;

bonding the segments onto the target object.

2. The method of claim 1 wherein the flexible membrane is further defined as a polyethylene terephthalate glycol-modified sheet.

3. The method of claim 1 wherein growing an epitaxial structure on a substrate further comprises:

growing sacrificial layer onto a semiconductor wafer; and

growing an active device region in an inverted order onto the sacrificial layer.

4. The method of claim 3 wherein forming the array of sensors further comprises:

selectively etching the sacrificial layer of the epitaxial structure to expose the active device region;

patterning the active device region to form individual sensors in the array of sensors;

further patterning the active device region to form interconnects between the individual sensors in the array of sensors; and

coating the array of sensors with an anti-reflection layer.

5. The method of claim 1 further comprises depositing gold onto the epitaxial structure and the flexible membrane prior to the step of bonding the epitaxial structure to a flexible membrane.

6. The method of claim 1 wherein the sensors in the array of sensors are further defined as photodiodes.

7. The method of claim 1 further comprises cutting the device structure into segments having shape of vesical piscis, wherein the target object is further defined as a sphere.

8. The method of claim 7 wherein bonding the segments onto the target object further comprises depositing water onto the non-developable surface of the target object, placing the segments over the non-developable surface of the target object, and baking the target object, thereby bonding the segments on the non-developable surface of the target object.

9. The method of claim 8 further comprises depositing anti-reflective coating onto the segments after the step of bonding the segments onto the target object.

10. A method for fabricating an array of sensors onto a sphere, comprising:

growing an epitaxial structure on a substrate;

bonding the epitaxial structure onto a flexible membrane to form a device structure;

forming, from the epitaxial structure of the device structure, an array of sensors using photolithographic techniques;

cutting the device structure into segments, each segment having shape of vesical piscis; and

bonding the segments onto a sphere.

11. The method of claim 10 wherein the flexible membrane is further defined as a polyethylene terephthalate glycol-modified sheet.

12. The method of claim 11 wherein growing an epitaxial structure on a substrate further comprises:

growing sacrificial layer onto a semiconductor wafer; and

growing an active device region in an inverted order onto the sacrificial layer.

13. The method of claim 12 wherein forming the array of sensors further comprises:

selectively etching the sacrificial layer of the epitaxial structure to expose the active device region;

patterning the active device region to form individual sensors in the array of sensors;

further patterning the active device region to form interconnects between the individual sensors in the array of sensors; and

coating the array of sensors with an anti-reflection layer.

14. The method of claim 13 further comprises depositing gold onto the epitaxial structure and the flexible membrane prior to the step of bonding the epitaxial structure to a flexible membrane.

15. A method for fabricating an array of sensors on an object having a non-developable surface, comprising:

growing sacrificial layer onto a semiconductor wafer; and

growing an active device region in an inverted order onto the sacrificial layer to form an epitaxial structure;

bonding, without the use of an adhesive, the epitaxial structure to a flexible membrane to form a device structure;

selectively etching the sacrificial layer of the epitaxial structure to expose the active device region;

patterning the active device region to form individual sensors in an array of sensors;

further patterning the active device region to form interconnects between the individual sensors in the array of sensors;

cutting the active device region into segments; and

bonding the segments onto the target object.