Claims
- 1. A method of fabricating an emitter plate for use in a field emission display device, said method comprising the steps of:
- providing an insulating substrate;
- forming a first conductive layer on said insulating substrate;
- forming an insulating layer on said first conductive layer;
- forming a second conductive layer on said insulating layer;
- forming a plurality of apertures through said second conductive layer and through said insulating layer;
- forming a lift-off layer on said second conductive layer, said lift-off layer formed by an electroplating process wherein a plating bath comprises at least one metal capable of existing in two oxidation states; and
- wherein said plating bath is saturated with oxygen.
- 2. The method in accordance with claim 1 further comprising the steps of:
- depositing conductive material through said plurality of apertures to form a microtip in each of said plurality of apertures; and
- removing said deposited conductive material and said lift-off layer from said second conductive layer.
- 3. The method in accordance with claim 2 wherein said deposited conductive material and said lift-off layer are removed by electrochemical dissolution using hydrochloric acid.
- 4. The method in accordance with claim 1 wherein said lift-off layer comprises nickel.
- 5. The method in accordance with claim 1 wherein said lift-off layer comprises nickel and iron.
- 6. The method in accordance with claim 1 wherein said plating bath further comprises boric acid.
- 7. The method in accordance with claim 1 wherein said plating bath further comprises sodium saccharinate.
- 8. The method in accordance with claim 1 wherein said plating bath comprises sulfate and chloride salts of nickel, and sulfate salts of ferrous iron.
- 9. The method in accordance with claim 1 wherein said plating process uses current densities between 4 and 8 mA/cm.sup.2.
- 10. The method in accordance with claim 1 wherein said plating bath has a pH between 2.7 and 3.1.
- 11. The method in accordance with claim 1 wherein said lift-off layer is approximately 150 nm thick.
- 12. The method in accordance with claim 1 wherein said lift-off layer comprises 20% iron and 80% nickel.
- 13. The method in accordance with claim 1 wherein said plating process is galvanostatically controlled.
- 14. The method in accordance with claim 1 further comprising the step of removing the lift-off layer with a potentiostatically controlled anodic dissolution process.
- 15. The method in accordance with claim 1 wherein said plating bath has a pH between 2.25 and 4.5 and wherein said plating process has a current density between 1 to 20 mA/cm.sup.2.
- 16. The method in accordance with claim 1 wherein said lift-off layer comprises permalloy.
- 17. A method of fabricating an emitter plate for use in a field emission display device, said method comprising the steps of:
- providing an insulating substrate;
- forming a first conductive layer on said insulating substrate;
- forming an insulating layer on said first conductive layer;
- forming a second conductive layer on said insulating layer; forming a plurality of apertures through said second conductive layer and through said insulating layer;
- forming a lift-off layer on said second conductive layer, said lift-off layer formed by an electroplating process wherein a plating bath comprises at least one metal capable of existing in two oxidation states; and
- wherein said plating process uses current densities between 4 and 8 mA/cm.sup.2, and further wherein said plating bath is saturated with oxygen.
- 18. A method of fabricating an emitter plate for use in a field emission display device, said method comprising the steps of:
- providing an insulating substrate;
- forming a first conductive layer on said insulating substrate;
- forming an insulating layer on said first conductive layer;
- forming a second conductive layer on said insulating layer;
- forming a plurality of apertures through said second conductive layer and through said insulating layer;
- forming a lift-off layer on said second conductive layer, said lift-off layer formed by an electroplating process wherein a plating bath comprises at least one metal capable of existing in two oxidation states; and
- wherein said plating bath has a pH between 2.6 and 3.1, and further wherein said plating bath is saturated with oxygen.
RELATED APPLICATIONS
This is a continuation-in-part of co-assigned, nonprovisional, U.S. patent application Ser. No. 08/622,081, filed Mar. 26, 1996 now abandoned, "Method Of Forming a Lift-Off Layer Having Controlled Adhesion Strength" (Texas Instruments Docket No. TI-20924).
US Referenced Citations (8)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
622081 |
Mar 1996 |
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