US5401668A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for fabrication solid state radiation imager having improved scintillator adhesion
Assignee: General Electric Co
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Filing: 1993-09-02
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Granted: 1995-03-28
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Expires: 2013-09-02
Abstract
Abstract A method of fabricating a radiation imager with strong structural integrity and adhesion between the scintillator and photosensor array includes the steps of forming a photosensor array on a substrate; depositing a barrier layer over the photosensor array, the barrier layer having an upper surface of silicon nitride; treating the silicon nitride upper surface of the barrier layer to prepare the surface for the deposition of material thereover; and depositing a scintillator material over the treated upper surface of the barrier layer. The silicon nitride upper surface of the barrier layer is typically treated by etching the surface, such as in a reactive ion etch, for a selected amount of time, with less than about 500 Å of material being removed from the surface.
Inventors
- 👤 Robert F. Kwasnick
- 👤 Roger S. Ehle
- 👤 Richard J. Saia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:49
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/30; H10F77/306; H10F77/40; H10F77/496; Y; Y10; Y10S; Y10S438/00; Y10S438/974
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
121 words
A method of fabricating a mechanically robust amorphous silicon imager having strong adhesion between the scintillator and an underlying moisture barrier layer, comprising the steps of: forming a photosensor array on a substrate; depositing a photosensor array barrier over said photosensor array, said array barrier having an upper surface comprising silicon nitride, said silicon nitride having a thickness of more than 500 Å; treating the silicon nitride surface of said barrier layer to provide enhanced adhesion of the silicon nitride to a scintillator material to be deposited thereover and so as not to remove more than 500 Å of said silicon nitride surface; and depositing a scintillator material over the treated surface of the silicon nitride surface of said barrier layer.
Claim 2
Independent Claim
121 words
A method of fabricating a mechanically robust amorphous silicon imager having strong adhesion between the scintillator and an underlying moisture barrier layer, comprising the steps of: forming a photosensor array on a substrate; depositing a photosensor array barrier over said photosensor array, said array barrier having an upper surface comprising silicon nitride, said silicon nitride having a thickness of more than 500 Å; treating the silicon nitride surface of said barrier layer to provide enhanced adhesion of the silicon nitride to a scintillator material to be deposited thereover and so as not to remove more than 500 Å of said silicon nitride surface; and depositing a scintillator material over the treated surface of the silicon nitride surface of said barrier layer.
Claim 3
Dependent Claim
27 words
The method of claim 1 wherein the step of treating said the silicon nitride surface of said barrier layer comprises reactive ion etching the silicon nitride surface.
Claim 4
Dependent Claim
47 words
The method of claim 2 wherein the step of reactive ion etching said silicon nitride surface of said barrier layer comprises the steps of exposing said silicon nitride surface to an etchant comprising a mixture of trifluoromethane (CHF 3 ), argon (Ar), and oxygen (O 2 ).
Claim 5
Dependent Claim
22 words
The method of claim 2 wherein the ratio of the mixture of CHF 3 , Ar, and O 2 is approximately 20:60:5.
Claim 6
Dependent Claim
31 words
The method of claim 2 wherein the time for etching said silicon nitride surface is selected so as to not etch away more than 500 Å of said silicon nitride surface.
Claim 7
Dependent Claim
33 words
The method of claim 1 wherein the step of treating said silicon nitride surface of said barrier layer comprises an etching process that is substantially selective to indium tin oxide and silicon oxide.
Claim 8
Dependent Claim
27 words
The method of claim 1 wherein the step of treating the silicon nitride surface of said barrier layer comprises ion bombardment of said upper silicon nitride layer.
Claim 9
Dependent Claim
24 words
The method of claim 1 wherein the step of treating the silicon nitride surface of said barrier layer comprises wet etching said silicon nitride.
Claim 10
Dependent Claim
23 words
The method of claim 8 wherein the step of wet etching said silicon nitride comprises applying an etchant comprising buffered hydrogen fluoride (BHF).
Claim 11
Dependent Claim
23 words
The method of claim 1 wherein the step of depositing said scintillator material comprises evaporating cesium iodide over the treated silicon nitride surface.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-03-27 | 1998-09-26 | 1999-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-03-27 | 2002-09-26 | 2003-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-03-27 | 2006-09-26 | 2007-03-28 | $7700.00 | Window Closed / Lapsed |