Methods and devices for detecting and measuring environmental conditions in high performance device packages

• US 8,711,361 B2
• Filed: 11/05/2009
• Issued: 04/29/2014
• Est. Priority Date: 11/05/2009
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm, Inc.
• Inventors: Bita, Ion
• Primary Examiner(s): Chowdhury, Tarifur
• Assistant Examiner(s): HANSEN, JONATHAN M
• Application Number:
  US12/613,396
• Publication Number:
  US 20110102800A1
• Time in Patent Office: 1,636 Days
• Field of Search: 356/450, 356/454, 356/519
• US Class Current: 356/454
• CPC Class Codes: G01N 2021/7773 Reflection
• CPC Class Codes: G01N 2021/7779 interferometric
• CPC Class Codes: G01N 21/77 by observing the effect on a chemical indicator
• CPC Class Codes: G01N 21/78 producing a change of colour
• CPC Class Codes: G01N 21/783 for analysing gases
• CPC Class Codes: G01N 21/81 Indicating humidity
• CPC Class Codes: G01N 33/18 Water

Abstract

An environmental condition sensing device includes an interferometric modulator with optical properties, which change in response to being exposed to a predetermined environmental threshold or condition. The device includes an environmental reactive layer, which alters composition, in an optically-detectable manner, in response to being exposed to a predetermined environmental threshold or condition.

Claims

1. An environmental condition monitoring device comprising:

an interferometric modulator comprising;

a substrate;

an optical enhancement layer disposed on the substrate, the optical enhancement layer comprising a reflector layer,

an environmental reactive layer disposed on the optical enhancement layer, the environmental reactive layer having a composition, the composition of the environmental reactive layer configured to alter in response to exposure to an environmental condition;

the environmental reactive layer and reflector layer defining boundaries for an interferometric cavity of the interferometric modulator, the environmental reactive layer being configured to act as an absorber layer of the interferometric modulator, a thickness of the environmental reactive layer being less than a thickness of the reflector layer, a reflectivity spectrum of the interferometric modulator being a function of the composition of the environmental reactive layer, wherein the environmental reactive layer is one of the following;

a metal, a metal alloy, and a semiconductor.

2. The environmental condition monitoring device of claim 1, wherein a thickness of the environmental reactive layer is less than 10 nm.

3. The environmental condition monitoring device of claim 1, wherein the environmental condition is water.

4. The environmental condition monitoring device of claim 1, wherein the environmental condition is a gas species.

5. The environmental condition monitoring device of claim 1, wherein a rate at which the composition of the environmental reactive layer alters in response to exposure to an environmental condition is altered by the dose of light to which the environmental reactive layer is exposed.

6. The environmental condition monitoring device of claim 1, wherein a rate at which the composition of the environmental reactive layer alters in response to exposure to an environmental condition is altered by the temperature to which the environmental reactive layer is exposed.

7. The environmental condition monitoring device of claim 1, further comprising a dielectric layer.

8. The environmental condition monitoring device of claim 1, wherein the environmental reactive layer is a metal.

9. The environmental condition monitoring device of claim 1, wherein the environmental reactive layer is a semi-conductor.

10. The environmental condition monitoring device of claim 1, wherein the reflectivity of the interferometric modulator at a selected wavelength is a function of the composition of the environmental reactive layer.

11. The environmental condition monitoring device of claim 1, wherein a chromaticity of the interferometric modulator is a function of the composition of the environmental reactive layer.

12. An environmental condition monitoring device comprising:

a substrate;

an optical enhancement means disposed on the substrate, the optical enhancement means comprising a light reflecting means; and

an absorber for altering the reflectivity spectrum of the light reflecting means in response to exposure to an environmental condition, wherein the absorber is disposed on the optical enhancement means,

the absorber and reflecting means defining boundaries for an interferometric cavity, a thickness of the absorber being less than a thickness of the reflecting means, wherein the absorber is one of the following;

a metal, a metal alloy, and a semiconductor.

13. The environmental condition monitoring device of claim 12, further comprising an interferometric modulator.

14. The environmental condition monitoring device of claim 12, wherein the absorber comprises an environmental reactive layer having a composition, the composition configured to alter in response to exposure to an environmental condition.

15. A method of manufacturing an environmental condition monitoring device, the method comprising:

providing a substrate;

forming an optical enhancement layer on the substrate, the optical enhancement layer including a reflector layer,

forming an environmental reactive layer on the optical enhancement layer,

the environmental reactive layer and reflector layer defining boundaries for an interferometric cavity of an interferometric modulator, the environmental reactive layer being configured to act as an absorber layer of the interferometric modulator, a thickness of the environmental reactive layer being less than a thickness of the reflector layer, a reflectivity of the interferometric modulator being a function of the composition of the environmental reactive layer, wherein the environmental reactive layer is one of the following;

a metal, a metal alloy, and a semiconductor.

16. The method of claim 15, further comprising configuring the interferometric modulator or the environmental reactive layer, so the reflectivity of the interferometric modulator at a selected wavelength is a function of the composition of the environmental reactive layer.

17. The method of claim 15, further comprising configuring the interferometric modulator to track changes in chromaticity of the interferometric modulator and the appearance of pinholes in the environmental reactive layer in response to exposure to the environmental condition.

18. A method of detecting exposure to an environmental condition, the method comprising:

providing an interferometric modulator having a reflector layer configured to substantially reflect light disposed on a substrate, and an environmental reactive layer, the environmental reactive layer disposed on a dielectric layer disposed on the reflector layer, a composition of the environmental reactive layer being configured to alter in response to exposure to the environmental condition, the environmental reactive layer and reflector layer defining boundaries for an interferometric cavity of the interferometric modulator, the environmental reactive layer being configured to act as an absorber layer of the interferometric modulator, a thickness of the environmental reactive layer being less than a thickness of the reflector layer, a reflectivity of the interferometric modulator being a function of the composition of the environmental reactive layer, wherein the environmental reactive layer is one of the following;

a metal, a metal alloy, and a semiconductor.

19. The method of claim 18, further comprising monitoring a change in chromaticity of the interferometric modulator and the appearance of pinholes in the environmental reactive layer in response to exposure to the environmental condition.