SUSPENDED THIN-FILM RESISTOR

• US 20040251117A1
• Filed: 06/16/2003
• Published: 12/16/2004
• Est. Priority Date: 06/16/2003
• Status: Active Grant

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Liu, Ling, Wong, Marvin Glenn
• Granted Patent: US 6,833,520 B1
• Time in Patent Office: Days
• US Class Current: 200/182
• CPC Class Codes: H01C 1/014 the resistor being suspended between and being supported by two supporting sections H01C1/016 takes precedence
• CPC Class Codes: H01C 17/075 by thin film techniques H01C17/20 takes precedence
• CPC Class Codes: H01C 17/288 by thin film techniques
• CPC Class Codes: H01H 2029/008 using micromechanics, e.g. micromechanical liquid contact switches or [LIMMS]

Abstract

A suspended thin-film resistor and methods for producing the same are disclosed. In one embodiment, a device is produced by depositing a first and second contact on a substrate, depositing a sacrificial material on the substrate at a location between the first and second contacts, depositing a thin-film resistor over the first and second contacts and the sacrificial material, and thermally decomposing the sacrificial material.

Claims

1. A device produced by:

depositing a first and second contact on a substrate;

depositing a sacrificial material, on the substrate at a location between the first and second contacts;

depositing a thin-film resistor over the first and second contacts and the sacrificial material; and

thermally decomposing the sacrificial material.

2. The device of claim 1, wherein the thin-film resistor comprises a metallic resistor.

3. The device of claim 2, wherein the metallic resistor comprises molybdenum.

4. The device of claim 1, wherein the sacrificial material comprises polynorbornene.

5. The device of claim 1, further comprising before depositing the thin-film resistor, depositing a first support layer on the sacrificial material, and wherein depositing the thin-film resistor comprises depositing the thin-film resistor on the first support layer.

6. The device of claim 5, further comprising after depositing the thin-film resistor, depositing a second support layer on the thin-film resistor.

7. The device of claim 6 wherein the first support layer and the second support layer comprise silicon nitride.

8. The device of claim 1, wherein the first and second contacts have a lower resistance than the thin-film resistor.

9. The device of claim 1, wherein depositing a thin-film resistor comprises depositing the thin-film resistor in a manner causing the thin-film resistor to be corrugated.

10. The device of claim 9, further comprising before depositing a sacrificial material, depositing support material on the substrate at a location between the first and second contacts, a section of the corrugated thin-film resistor being deposited on the support material.

16. The device of claim 11, wherein the thin-film resistor comprises a metal resistor.

11. A device comprising:

a substrate supporting first and second contacts;

a thin-film resistor deposited on the first and second contacts, a section of the thin-film resistor between the first and second contacts being suspended above the substrate.

12. The device of claim 11, further comprising first and second conductive vias leading from a surface of the substrate to third and fourth contacts deposited on an opposite surface of the substrate.

13. The device of claim 11, further comprising support material deposited at a location between first and second contacts, the support material to support a portion of the thin-film resistor.

14. The device of claim 13, wherein the thin-film resistor comprises a corrugated material, a section of the thin-film resistor deposited on the support material.

15. The device of claim 11, wherein the first and second contacts have a lower resistance than the thin-film resistor.

17. A method comprising:

depositing a first and second contact on a substrate;

depositing a sacrificial material on the substrate and the first and second contacts, at a location between the first and second contacts;

depositing a thin-film resistor over the first and second contacts and the sacrificial material; and

thermally decomposing the sacrificial material.

18. The method of claim 17, wherein depositing a sacrificial material comprises:

spin coating the sacrificial material on the substrate and the first and second contacts;

depositing a mask layer on the sacrificial material;

depositing photoresist material on the mask layer at a location between first and second contacts;

etching at least a portion of the mask layer;

removing the photoresist material; and

reactive ion etching the sacrificial material not layered by the mask layer; and

etching away at least a portion of the mask layer.

19. The method of claim 17, wherein the sacrificial material comprises polynorbornene.

20. A switch comprising:

first and second mated substrates defining therebetween at least portions of a number of cavities;

a switching fluid, held within one or more of the cavities, that is movable between at least first and second switch states in response to forces that are applied to the switching fluid;

an actuating fluid, held within one or more of the cavities, that applies said forces to said switching fluid;

first and second contacts, deposited on the first substrate at a location that is within one of the cavities holding the actuating fluid; and

a thin-film resistor heater, deposited on the first and second contacts, a section of the thin-film resistor heater between the first and second contacts being suspended above the first substrate.

21. The switch of claim 20, wherein the thin-film resistor comprises a corrugated material.

22. The switch of claim 20, wherein the first and second contacts have a lower resistance than the thin-film resistor.