Microstructured surface with low work function

Patent metadata

Field	Value
Publication number	US-9536696-B1
Application number	US-201615013699-A
Country	US
Kind code	B1
Filing date	Feb 2, 2016
Priority date	Feb 2, 2016
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A horizontal multilayer junction-edge field emitter includes a plurality of vertically-stacked multilayer structures separated by isolation layers. Each multilayer structure is configured to produce a 2-dimensional electron gas at a junction between two layers within the structure. The emitter also includes an exposed surface intersecting the 2-dimensional electron gas of each of the plurality of vertically-stacked multilayer structures to form a plurality of effectively one-dimensional horizontal line sources of electron emission.

First claim

What is claimed is:

1. A horizontal multilayer junction-edge field emitter (HMJFE), comprising:
a plurality of vertically-stacked multilayer structures, separated by isolation layers, each structure being configured to produce a 2-dimensional electron gas (2DEG) at a junction between two layers within the structure; and
an exposed surface intersecting the 2DEG of each of the plurality of vertically-stacked multilayer structures to form a plurality of effectively one-dimensional horizontal line sources of electron emission.

2. The HMJFE of claim 1 , wherein each of the plurality of vertically-stacked multilayer structures includes a first layer including a first semiconductor and a second layer including one of a second semiconductor different from the first semiconductor, an oxide, or a metal.

3. The HMJFE of claim 2 , wherein the 2DEG is formed at a junction of the first layer and the second layer.

4. The HMJFE of claim 2 , wherein the second layer includes an oxide insulator, the second layer is disposed between the first layer and a third layer including a second semiconductor different from the first semiconductor, and the HMJFE includes an external voltage source configured to apply a bias across the first layer and the third layer to enhance formation of the 2DEG.

5. The HMJFE of claim 1 , further comprising a substrate attached to a layer of the plurality of vertically-stacked multilayer structures.

6. The HMJFE of claim 1 , further comprising an anode spaced from the plurality of vertically-stacked multilayer structures, the anode configured to capture electrons emitted from the effectively one-dimensional horizontal line sources.

7. The HMJFE of claim 6 , wherein the anode includes a trough configured to transport the captured electrons.

8. The HMJFE of claim 6 , wherein the anode is biased relative to the 2DEG.

9. The HMJFE of claim 6 , wherein the anode is configured to be a constant distance from at least a portion of the exposed surface.

10. The HMJFE of claim 6 , further comprising a grid located between the exposed surface and the anode, the grid configured to be biased to alter an electric field distribution between the exposed surface and the anode.

11. The HMJFE of claim 1 , wherein a first multilayer structure is electrically connected to a first external voltage source and a second multilayer structure is electrically connected to a second external voltage source.

12. The HMJFE of claim 11 , wherein the first external voltage source applies a first bias across the first multilayer structure and the second external voltage source applies a second bias across the second multilayer structure.

13. The HMJFE of claim 1 , wherein the exposed surface is formed by depositing materials forming the plurality of vertically-stacked multilayer structures through a mask.

14. The HMJFE of claim 1 , wherein the exposed surface is formed by removing material from the plurality of vertically-stacked multilayer structures.

15. A horizontal multilayer junction-edge field emitter (HMJFE), comprising:
a first substrate including a first surface;
a first plurality of vertically-stacked multilayer structures, separated by isolation layers, each structure being configured to produce a first 2-dimensional electron gas (2DEG) at a junction between two layers within the structure, the first plurality of vertically-stacked multilayer structures attached to the first surface;
a second plurality of vertically-stacked multilayer structures, separated by isolation layers, each structure being configured to produce a second 2DEG at a junction between two layers within the structure, the second plurality of vertically-stacked multilayer structures attached to the first surface and spaced apart from the first plurality of vertically-stacked multilayer structures; and
a first anode attached to the first surface of the first substrate and configured to collect electrons emitted by the first 2DEG.

16. The HMJFE of claim 15 , wherein:
a first anode surface of the anode is oriented to face the first plurality of vertically-stacked multilayer structures to collect electrons emitted by the first 2DEG; and
a second anode surface of the anode is located on an opposite side of the anode from the first anode surface and oriented to face the second plurality of vertically-stacked multilayer structures to collect electrons emitted by the second 2DEG.

17. The HMJFE of claim 16 , wherein the first anode surface is parallel to an exposed surface of the first plurality of vertically-stacked multilayer structures.

18. The HMJFE of claim 16 , wherein an exposed surface of at least one of the first plurality of vertically-stacked multilayer structures or the second plurality of vertically-stacked multilayer structures is positioned oblique to the first surface of the first substrate.

19. The HMJFE of claim 15 , wherein the first anode is attached to a second substrate spaced apart from the first substrate, the first plurality of vertically-stacked multilayer structures, and the second plurality of vertically-stacked multilayer structures.

20. The HMJFE of claim 15 , further comprising an insulator adjacent to an opposite side of the first anode from the first plurality of vertically-stacked multilayer structures and adjacent to the second plurality of vertically-stacked multilayer structures.

21. The HMJFE of claim 15 , wherein a non-uniform bias is applied between the first anode and at least one of the pluralities of multilayer structures.

22. A vertical-emitting junction-edge field emitter structure (VEJFE), comprising:
a plurality of vertical structures formed on a substrate, wherein each vertical structure includes at least two vertically oriented layers, each vertical structure is configured to produce a 2DEG at a junction between two of the vertically-oriented layers, and each vertical structure is truncated to expose an edge of the 2DEG.

23. The VEFJE of claim 22 , wherein each vertical structure is truncated on an opposite side of the vertical structure from the substrate.

24. The VEJFE of claim 22 , further comprising an electrode structure arranged above the exposed edges of the 2DEGs of the vertical structures.

25. The VEJFE of claim 24 , wherein the electrode structure comprises an anode configured to collect electrons emitted by each 2DEG out of the exposed junction edges.

26. The VEFJE of claim 24 , wherein the electrode structure comprises a control grid configured to control an electric field between the vertical structures and the control grid.

27. The VEJFE of claim 24 , wherein the electrode structure comprises a continuous planar structure.

28. The VEJFE of claim 24 , wherein the electrode structure comprises a planar array of apertures.

29. The VEFJE of claim 24 , wherein the electrode structure comprises a single electrode structure for the plurality of vertical structures.

30. The VEFJE of claim 24 , wherein the electrode structure comprises a plurality of electrically-separated electrode assemblies.

31. The VEFJE of claim 22 , wherein at least one vertical structure includes an electrode structure.

32. The VEFJE of claim 31 , wherein the electrode structure includes an anode configured to collect electrons emitted by the 2DEG of the at least one vertical structure.

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Assignees

• Elwha Llc

Inventors

• Hyde Roderick A
• Kare Jordin T
• Pan Tony S
• Wood Jr Lowell L

Classifications

• H01J1/3046

  Edge emitters · CPC title

• H01J19/24 Primary

  Cold cathodes, e.g. field-emissive cathode · CPC title

• H01J1/304 Primary

  Field-emissive cathodes · CPC title

• H01J2209/0223

  Field emission cathodes · CPC title

• H01J9/18

  Assembling together the component parts of electrode systems · CPC title