Claims
- 1. A method of manufacturing a radiation detector having conductive contacts on a semiconductor substrate at positions for defining radiation detector cells, said method including:
a) forming one or more layers of material on a surface of said substrate with openings to said substrate surface at said contact positions; b) forming a layer of conductive material over said layer(s) of material and said openings; and c) removing portions of the conductive material overlying said layer(s) of material to separate individual contacts.
- 2. A method according to claim 1, wherein said one or more layers of material include a passivation layer and a layer of a photoresistive material.
- 3. A method according to claim 2, further comprising removing said layer of the photoresistive material.
- 4. A method according to claim 3, wherein said photoresistive material is removed from an area greater than said contact positions to expose adjacent portions of said passivation material.
- 5. A method according to claim 4, wherein after removal of said conductive material, said contacts cover said openings and also extend up and laterally beyond said openings.
- 6. A method according to claim 1, wherein the substrate is formed of cadmium zinc telluride or cadmium telluride.
- 7. A method according to claim 1, wherein said conductive material layer forming said contacts is applied by sputtering, evaporation, or electrolytic deposition.
- 8. A method according to claim 1, wherein said conductive material is a metal or metal alloy or cadmium sulfide.
- 9. A method according to claim 8, wherein said metal or metal alloy for forming said contacts comprises nickel, gold, platinum, indium, nickel/gold alloy, titanium/tungsten alloy.
- 10. A method according to claim 2, wherein said passivation layer is aluminum nitride.
- 11. A method according to claim 1, wherein each conductive contact defines a respective pixel cell of an array of pixel cells.
- 12. A method according to claim 1, wherein each conductive contact defines one of a plurality of strips arranged parallel to each other.
- 13. A method according to claim 12, wherein said conductive contacts are of the order of 10 μm across with a spacing of the order of 5 μm.
- 14. A method according to claim 1, wherein the plurality of said conductive contacts for respective radiation detector cells are formed on a first surface of said semiconductor substrate, and a layer of conductive material is formed on a surface of said substrate opposite to said first surface.
- 15. A method according to claim 14, including, prior to step (a), a step of forming said layer of conductive material on said second surface of said substrate.
- 16. A method of manufacturing a radiation imaging device comprising:
manufacturing a radiation detector in accordance with claim 15; and individually connecting individual detector cell contacts for respective detector cells to corresponding circuits on a readout chip by a flip-chip technique.
- 17. A radiation detector comprising a semiconductor substrate with a plurality of conductive contacts for respective radiation detector cells on a first surface thereof and a layer of conductive material on a surface of said substrate opposite to said first surface, said radiation detector being manufactured by a method in accordance to claim 14.
- 18. A radiation detector according to claim 17, comprising passivation material between individual contacts.
- 19. A radiation detector according to claim 18, wherein said passivation material is aluminum nitride.
- 20. A radiation detector according to claim 17, wherein said conductive contacts define an array of pixel cells.
- 21. A radiation detector according to claim 20, wherein said contacts are substantially circular and are arranged in a plurality of rows, with alternate rows preferably being offset from adjacent rows.
- 22. A radiation detector according to claim 17, wherein said conductive contacts define a plurality of strips arranged parallel to each other.
- 23. A radiation detector according to claim 17, wherein said metal contacts are of the order of 10 μm across with a spacing of the order of 5 μm.
- 24. A radiation detector according to claim 17, wherein said semiconductor substrate is cadmium zinc telluride or cadmium telluride.
- 25. A radiation detector according to claim 17, wherein the resistivity between conductive contacts is in excess of IG′Ω/square, preferably in excess of 10 G′Ω/square, more preferably in excess of 100 G′Ω/square and even more preferably in excess of 1000 G′Ω/square (1 TΩ/square).
- 26. A radiation imaging device comprising a radiation detector in accordance with claim 17, and a readout chip having circuits for accumulating charge from successive radiation hits, individual contacts for respective detector cells being connected by a flip-chip technique to respective circuits for accumulating charge.
- 27. A method of manufacturing a radiation imaging device comprising:
manufacturing a radiation detector in accordance with claim 15, and individually connecting individual detector cell contacts for respective detector cells to corresponding circuits on a readout chip by a flip-chip technique.
- 28. A radiation detector comprising a semiconductor substrate with a plurality of conductive contacts for respective radiation detector cells on a first surface thereof and a layer of conductive material on a surface of said substrate opposite to said first surface, said radiation detector being manufactured by a method in accordance with claim 15.
Priority Claims (1)
Number |
Date |
Country |
Kind |
9916404.8 |
Jul 1999 |
GB |
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of appliction Ser. No. 09/362,195 filed Jul. 28, 1999, which is a continuation-in-part of application Ser. No. 08/755,826 filed Nov. 26, 1996, now U.S. Pat. No. 6,046,068.
Continuations (1)
|
Number |
Date |
Country |
Parent |
09362195 |
Jul 1999 |
US |
Child |
10176637 |
Jun 2002 |
US |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
08755826 |
Nov 1996 |
US |
Child |
09362195 |
Jul 1999 |
US |