Semiconductor device having a surface conducting channel and method of forming

• US 20070141789A1
• Filed: 12/20/2005
• Published: 06/21/2007
• Est. Priority Date: 12/20/2005
• Status: Active Grant

• Current Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Original Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Inventors: Kiesel, Peter, Schmidt, Oliver, Johnson, Noble, Geis, Arnd
• Granted Patent: US 7,314,801 B2
• Time in Patent Office: Days
• US Class Current: 438/282
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A semiconductor device including a metal oxide layer, a channel area of the metal oxide layer, a preservation layer formed on the channel area of the metal oxide layer, and at least two channel contacts coupled to the channel area of the metal oxide layer, and a method of forming the same.

Claims

1. A semiconductor device comprising:

a metal oxide layer having a surface region and a bulk region;

a channel area of the surface region of the metal oxide layer having a resistivity lower than a resistivity of the bulk region of the metal oxide layer;

a preservation layer formed on the channel area; and

at least two channel contacts coupled to the channel area of the metal oxide layer.

2. The semiconductor device of claim 1, the metal oxide layer further comprising one selected from the group consisting of a zinc oxide layer and a magnesium zinc oxide layer.

3. The semiconductor device of claim 1, the preservation layer overlapping the channel contacts.

4. The semiconductor device of claim 1, the channel contacts further comprising:

a source contact; and

a drain contact.

5. The semiconductor device of claim 1, wherein all of a surface of the metal oxide layer disposed between any two of the channel contacts is covered by the preservation layer.

6. The semiconductor device of claim 1, further comprising one selected from the group consisting of:

an isolation region in the metal oxide layer surrounding the preservation layer and the at least two channel contacts;

an insulating preservation layer on the surface substantially surrounding the semiconductor device; and

the metal oxide layer further comprising a mesa of the metal oxide.

7. The semiconductor device of claim 6, wherein the insulating preservation layer further comprises at least one selected from the group consisting of polyimide and a self-assembled monolayer.

8. The semiconductor device of claim 1, the metal oxide layer further comprising the metal oxide layer formed on a semiconductor substrate.

9. The semiconductor device of claim 1, further comprising a gate formed on the preservation layer substantially over every path between the channel contacts through the preservation layer.

10. The semiconductor device of claim 9, the gate further comprising at least one selected from the group consisting of a metal layer and a transparent conductive oxide layer.

11. The semiconductor device of claim 9, the gate further comprising one selected from the group consisting of a biological gate and a chemical gate.

12. The semiconductor device of claim 1, the preservation layer being substantially impermeable to at least one of a gas, oxygen, nitrogen, and a molecule including a hydroxyl group.

13. A method of making a semiconductor device comprising:

providing a metal oxide layer having a surface;

inducing the metal oxide layer to transition to a surface conducting state;

forming a preservation layer on at least a part of the surface to define a channel area; and

forming at least two channel contacts coupled to the channel area.

14. The method of making a semiconductor device of claim 13, providing the metal oxide layer further comprises one selected from the group consisting of providing a zinc oxide layer and providing a magnesium zinc oxide layer.

15. The method of making a semiconductor device of claim 13, forming the channel contacts further comprising:

removing an area of the preservation layer for each channel contact;

forming each channel contact on the respective area removed from the preservation layer.

16. The method of making a semiconductor device of claim 13, further comprising one of the group consisting of:

doping the metal oxide layer to create a high resistivity area outside of the channel area;

forming a mesa of the metal oxide layer to provide the surface of the metal oxide layer; and

forming an insulating preservation layer on the surface substantially surrounding the semiconductor device.

17. The method of making a semiconductor device of claim 13, forming the preservation layer further comprising forming the preservation layer on all areas of the surface of the metal oxide layer between any two of the channel contacts.

18. The method of making a semiconductor device of claim 13, providing the surface of the metal oxide layer further comprising forming the metal oxide layer on a semiconductor substrate.

19. The method of making a semiconductor device of claim 13, further comprising forming a gate on the preservation layer substantially over every path over the preservation layer between the channel contacts.

20. The method of making a semiconductor device of claim 19, wherein forming a gate further comprises forming at least one selected from the group consisting of a metal gate, a transparent conducting metal oxide, a biological gate, and a chemical gate.