Amorphous metal thin-film non-linear resistor

• US 9,099,230 B2
• Filed: 10/30/2013
• Issued: 08/04/2015
• Est. Priority Date: 11/12/2012
• Status: Active Grant

• Current Assignee: Oregon State University (Oregon University System)
• Original Assignee: Oregon State University (Oregon University System)
• Inventors: Cowell, E. William III
• Primary Examiner(s): Lee, Kyung
• Application Number:
  US14/066,945
• Publication Number:
  US 20140368310A1
• Time in Patent Office: 643 Days
• Field of Search: 338/327, 338/306, 338/13, 257/E21.004, 257/378
• US Class Current: 1/1
• CPC Class Codes: H01C 1/14 Terminals or tapping points or electrodes specially adapted for resistors in general H01R; Arrangements of terminals or tapping points or electrodes on resistors
• CPC Class Codes: H01C 1/142 the terminals or tapping points being coated on the resistive element
• CPC Class Codes: H01C 17/12 by sputtering
• CPC Class Codes: H01C 7/006 Thin film resistors
• CPC Class Codes: H01L 28/20 Resistors
• CPC Class Codes: H01L 28/24 with an active material comprising a refractory, transition or noble metal, metal compound or metal alloy, e.g. silicides, oxides, nitrides

Abstract

An amorphous metal thin-film non-linear resistor (AMNR) is provided. The AMNR is an electronic device possessing symmetric non-linear current-voltage (I-V) characteristics, an exemplary configuration of which may comprise three sequentially deposited layers which include a lower amorphous metal thin-film (AMTF) interconnect, a thin-film insulator located on top of the AMTF interconnect, and two upper conductive contacts located on top of the insulator and disposed in the same physical plane.

Claims

1. An amorphous metal thin-film nonlinear resistor possessing symmetric nonlinear current-voltage characteristics, comprising:

an amorphous metal thin-film interconnect;

an insulator layer disposed over the interconnect; and

first and second electrical contacts disposed over a selected surface of the insulator layer and interconnect, each connector having at least a respective portion thereof overlapping a respective portion of the interconnect to provide electrical communication from the first contact through the insulator layer and amorphous metal interconnect to the second contact,

whereby a voltage applied across the first and second electrical contacts results in an electrical current that varies nonlinearly with, and symmetrically with polarity of, applied voltage.

2. The amorphous metal thin-film nonlinear resistor according to claim 1, wherein the amorphous metal thin-film interconnect contains at least two of the elements aluminum, titanium, zirconium, copper, nickel, tantalum, tungsten, boron, or silicon.

3. The amorphous metal thin-film nonlinear resistor according to claim 1, wherein the amorphous metal thin-film interconnect comprises levels of oxygen, nitrogen, and carbon making up less than 5% of the atomic composition of the amorphous metal interconnect.

4. The amorphous metal thin-film nonlinear resistor according to claim 1, wherein the insulator comprises an oxide material containing oxygen and one of the elements aluminum, titanium, zirconium, hafnium, tantalum, or silicon.

5. The amorphous metal thin-film nonlinear resistor according to claim 1, wherein the contacts comprise a conductive material made of the metallic elements aluminum, chromium, molybdenum, titanium, copper, and nickel, the indium tin oxide, and combinations thereof.

6. The amorphous metal thin-film nonlinear resistor according to claim 1, wherein amorphous metal thin-film interconnect has a root mean square surface roughness of less than about 2 nm.

7. The amorphous metal thin-film nonlinear resistor according to claim 1, wherein amorphous metal thin-film interconnect has a resistivity greater than 125 μ

Ω

-cm and less than 400 μ

Ω

-cm.

8. A method of fabricating an amorphous metal thin-film nonlinear resistor, comprising:

depositing an amorphous metal thin-film interconnect on a substrate;

depositing an insulator layer over the interconnect; and

forming first and second electrical contacts over a selected surface of the insulator layer and interconnect, each connector having at least a respective portion thereof overlapping a respective portion of the interconnect to provide electrical communication from the first contact through the insulator layer and amorphous metal interconnect to the second contact,

whereby a voltage applied across the first and second electrical contacts results in an electrical current that varies nonlinearly with, and symmetrically with polarity of, applied voltage.

9. The method according to claim 8, wherein the step of depositing the amorphous metal thin-film interconnect layer comprises one or more of direct current magnetron sputtering and radio frequency magnetron sputtering.

10. The method according to claim 8, wherein the step of depositing the insulator layer comprises one or more of atomic layer deposition, plasma enhanced chemical vapor deposition, radio frequency magnetron sputtering, aqueous solution deposition, and mist deposition.

11. The method according to claim 8, wherein the step of forming the first and second electrical contacts comprises one or more of thermal evaporation, direct current magnetron sputtering, radio frequency magnetron sputtering, and electron beam deposition.