US4943343A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-aligned gate process for fabricating field emitter arrays
Assignee: L3 Communications Electron Technologies Inc
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Filing: 1989-08-14
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Granted: 1990-07-24
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Expires: 2009-08-14
Abstract
Abstract Conical field emitter elements are formed on a surface of a substrate after which a layer of metal is deposited on top of the substrate surface and over the field emitter elements. A layer of oxide is then deposited over the metal layer. Another layer of metal is deposited over the layer of oxide to form a gate metal layer. A layer of photoresist is then deposited over the gate metal layer. The layer of photoresist is then plasma etched in an oxygen atmosphere to cause portions of the photoresist above respective field emitter elements to be removed and provide self-aligned holes in the photoresist over each of the field emitter elements. The size of the holes may be controlled by appropriately controlling process parameter, including plasma etching time and power and/or initial photoresist thickness. The exposed gate metal layer is etched using the layer of photoresist as a mask. The photoresist layer is removed, and the layer of oxide is etched to expose the field emitter elements. Another oxide layer and an anode metal layer also may be formed over the gate metal layer to produce a self-aligned triode structure.
Inventors
- 👤 Zaher Bardai
- 👤 Randy K. Rolph
- 👤 Arlene E. Lamb
- 👤 Robert T. Longo
- 👤 Arthur E. Manoly
- 👤 Ralph Forman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:58
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/022; H01J9/025
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
146 words
A process for fabricating a field emitter array, said process comprising the steps of; forming substantially conical field emitter elements on a surface of a substrate; depositing a layer of oxide over said substrate surface and said field emitter elements; depositing a layer of metal over said layer of oxide to form a gate metal layer; depositing a layer of photoresist over said gate metal layer; plasma etching said layer of photoresist in an oxygen atmosphere to cause portions of photoresist above respective field emitter elements to be removed and thereby expose respective portions of said gate metal layer above respective tip regions of said field emitter elements; etching the exposed portions of said gate metal layer using said layer of photoresist as a mask; removing said layer of photoresist; and etching the exposed portions of said layer of oxide to expose said field emitter elements.
Claim 2
Dependent Claim
146 words
A process for fabricating a field emitter array, said process comprising the steps of; forming substantially conical field emitter elements on a surface of a substrate; depositing a layer of oxide over said substrate surface and said field emitter elements; depositing a layer of metal over said layer of oxide to form a gate metal layer; depositing a layer of photoresist over said gate metal layer; plasma etching said layer of photoresist in an oxygen atmosphere to cause portions of photoresist above respective field emitter elements to be removed and thereby expose respective portions of said gate metal layer above respective tip regions of said field emitter elements; etching the exposed portions of said gate metal layer using said layer of photoresist as a mask; removing said layer of photoresist; and etching the exposed portions of said layer of oxide to expose said field emitter elements.
Claim 3
Dependent Claim
17 words
A process according to claim 1 wherein said substrate and said field emitter elements are of polysilicon.
Claim 4
Dependent Claim
45 words
A process according to claim 1 wherein the step of depositing a layer of metal over said layer of oxide comprises the steps of: depositing a layer of chromium on said layer of oxide; and depositing a layer of gold on said layer of chromium.
Claim 5
Dependent Claim
56 words
A process according to claim 1 wherein the step of plasma etching said layer of photoresist comprises the steps of: placing said substrate in plasma discharge apparatus; evacuating the apparatus to a predetermined pressure; passing a regulated flow of oxygen gas over said substrate; and establishing a plasma discharge in said apparatus for a predetermined time.
Claim 6
Dependent Claim
160 words
A process for fabricating a field emitter array, said process comprising the steps of; forming substantially conical field emitter elements on a surface of a substrate; depositing a first layer of metal on said substrate surface and over said field emitter elements; depositing a layer of oxide over said first layer of metal; depositing a second layer of metal over said layer of oxide to form a gate metal layer: depositing a layer of photoresist over said gate metal layer; plasma etching said layer of photoresist in an oxygen atmosphere to cause portions of photoresist above respective field emitter elements to be removed and thereby expose respective portions of said gate metal layer above respective tip regions of said field emitter elements; etching the exposed portions of said gate metal layer using the layer of photoresist as a mask; removing said layer of photoresist; and etching the exposed portions of said layer of oxide to expose said field emitter elements.
Claim 7
Dependent Claim
160 words
A process for fabricating a field emitter array, said process comprising the steps of; forming substantially conical field emitter elements on a surface of a substrate; depositing a first layer of metal on said substrate surface and over said field emitter elements; depositing a layer of oxide over said first layer of metal; depositing a second layer of metal over said layer of oxide to form a gate metal layer: depositing a layer of photoresist over said gate metal layer; plasma etching said layer of photoresist in an oxygen atmosphere to cause portions of photoresist above respective field emitter elements to be removed and thereby expose respective portions of said gate metal layer above respective tip regions of said field emitter elements; etching the exposed portions of said gate metal layer using the layer of photoresist as a mask; removing said layer of photoresist; and etching the exposed portions of said layer of oxide to expose said field emitter elements.
Claim 8
Dependent Claim
17 words
A process according to claim 5 wherein said substrate and said field emitter elements are of polysilicon.
Claim 9
Dependent Claim
15 words
A process according to claim 5 wherein said first layer of metal is of molybdenum.
Claim 10
Dependent Claim
46 words
A process according to claim 5 wherein the step of depositing a second layer of metal over said layer of oxide comprises the steps of: depositing a layer of chromium on said layer of oxide; and depositing a layer of gold on said layer of chromium.
Claim 11
Dependent Claim
56 words
A process according to claim 5 wherein the step of plasma etching said layer of photoresist comprises the steps of: placing said substrate in plasma discharge apparatus; evacuating the apparatus to a predetermined pressure; passing a regulated flow of oxygen gas over said substrate; and establishing a plasma discharge in said apparatus for a predetermined time.
Claim 12
Dependent Claim
275 words
A process for fabricating a field emitter triode array, said process comprising the steps of: forming substantially conical field emitter elements on a surface of a substrate; depositing a first layer of oxide over said substrate surface and said field emitter elements; depositing a layer of metal over said layer of oxide to form a gate metal layer; depositing a first layer of photoresist over said gate metal layer; plasma etching said first layer of photoresist in an oxygen atmosphere to cause portions of photoresist above respective field emitter elements to be removed and thereby expose respective portions of said gate metal layer above respective tip regions of said field emitter elements; etching the exposed portions of said gate metal layer using said first layer of photoresist as a mask; removing said first layer of photoresist; depositing a second layer of oxide over said gate metal layer and over respective portions of said first oxide layer not covered by said gate metal layer; depositing a layer of metal over said second layer of oxide to form an anode metal layer; depositing a second layer of photoresist over said anode metal layer; plasma etching said second layer of photoresist in an oxygen atmosphere to cause portions of photoresist in said second layer above respective field emitter elements to be removed and thereby expose respective portions of said anode metal layer above respective tip regions of said field emitter elements; etching the exposed portions of said anode metal layer using said second layer of photoresist as a mask; and etching the exposed portions of said first and second layers of oxide to expose said field emitter elements
Claim 13
Dependent Claim
275 words
A process for fabricating a field emitter triode array, said process comprising the steps of: forming substantially conical field emitter elements on a surface of a substrate; depositing a first layer of oxide over said substrate surface and said field emitter elements; depositing a layer of metal over said layer of oxide to form a gate metal layer; depositing a first layer of photoresist over said gate metal layer; plasma etching said first layer of photoresist in an oxygen atmosphere to cause portions of photoresist above respective field emitter elements to be removed and thereby expose respective portions of said gate metal layer above respective tip regions of said field emitter elements; etching the exposed portions of said gate metal layer using said first layer of photoresist as a mask; removing said first layer of photoresist; depositing a second layer of oxide over said gate metal layer and over respective portions of said first oxide layer not covered by said gate metal layer; depositing a layer of metal over said second layer of oxide to form an anode metal layer; depositing a second layer of photoresist over said anode metal layer; plasma etching said second layer of photoresist in an oxygen atmosphere to cause portions of photoresist in said second layer above respective field emitter elements to be removed and thereby expose respective portions of said anode metal layer above respective tip regions of said field emitter elements; etching the exposed portions of said anode metal layer using said second layer of photoresist as a mask; and etching the exposed portions of said first and second layers of oxide to expose said field emitter elements
Claim 14
Dependent Claim
17 words
A process according to claim 10 wherein said substrate and said field emitter elements are of polysilicon.
Claim 15
Dependent Claim
51 words
A process according to claim 11 wherein the step of depositing a layer of metal over said layer of oxide to form a gate metal layer comprises the steps of: depositing a layer of chromium on said layer of oxide; and depositing a layer of gold on said layer of chromium.
Claim 16
Dependent Claim
61 words
A process according to claim 10 wherein the steps of plasma etching said first and said second layers of photoresist each comprises the steps of: placing said substrate in plasma discharge apparatus; evacuating the apparatus to a predetermined pressure; passing a regulated flow of oxygen gas over said substrate; and establishing a plasma discharge in said apparatus for a predetermined time.
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