Method of passivating and encapsulating CdTe and CZT segmented detectors
A method of forming a passivation layer comprises contacting at least one surface of a wide band-gap semiconductor material with a passivating agent comprising an alkali hypochloride to form the passivation layer on said at least one surface. The passivation layer may be encapsulated with a layer of encapsulation material.
1. A method of forming a passivation layer comprising:
contacting at least one surface of a wide band-gap semiconductor material with a passivating agent comprising an alkali hypochloride to form the passivation layer on said at least one surface.
2. The method of claim 1 , wherein semiconductor material comprises a semiconductor substrate.
3. The method of claim 2 , wherein:
the semiconductor substrate comprises a substrate of a multi-channel monolithic radiation detector;
the semiconductor substrate has opposing front and rear surfaces;
a cathode electrode is located on the front surface of said semiconductor substrate; and
a segmented anode electrode array is located on the rear surface of said semiconductor substrate.
4. The method of claim 1 , wherein the wide band-gap semiconductor material comprises a II-VI semiconductor substrate.
5. The method of claim 4 , wherein the alkali hypochloride comprises NaOCl.
6. The method of claim 5 , wherein the semiconductor material comprises cadmium telluride or cadmium zinc telluride.
7. The method of claim 4 , wherein the passivation layer comprises an oxide of the II-VI semiconductor material.
8. The method of claim 3 , wherein the passivation layer is formed at least between anode electrodes of the segmented anode electrode array.
9. The method of claim 3 , wherein the passivation layer is formed at least on sidewalls of the substrate.
10. The method of claim 1 , wherein the step of contacting comprises immersing the semiconductor material in a solution comprising the passivating agent.
11. A method of passivating a monolithic, multichannel semiconductor radiation detector comprising:
providing a cadmium telluride or cadmium zinc telluride substrate having a segmented anode electrode array on a first surface of the substrate and a cathode electrode on a second surface of the substrate; and
forming a passivation layer at least between the anode electrodes of the anode electrode array by contacting the first surface of the substrate with a solution comprising sodium hypochloride.
12. The method of claim 11 , wherein the semiconductor substrate comprises cadmium zinc telluride.
13. The method of claim 11 , wherein the step of contacting lasts between about 5 and about 60 minutes.
14. The method of claim 11 , wherein a passivation layer is further formed on sidewalls of the substrate.
15. The method of claim 11 , wherein the cathode electrode is formed before the passivation layer.
16. The method of claim 11 , wherein the cathode electrode is formed after the passivation layer.
17. The method of claim 11 , wherein a thickness of the passivation layer in between the anode electrodes is less than or equal to a height of the anode electrodes.
18. The method of claim 11 , wherein the passivation layer comprises an oxide of cadmium telluride or an oxide of cadmium zinc telluride.
19. The method of claim 11 , further comprising drying said first surface of the substrate.
20. A device formed according to the method of claim 1 .
21. A device formed according to the method of claim 11 .