INTERFEROMETRIC MASKS

• US 20120042931A1
• Filed: 10/27/2011
• Published: 02/23/2012
• Est. Priority Date: 11/07/2007
• Status: Abandoned Application

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Kothari, Manish, Khazeni, Kasra
• Application Number:
  US13/282,809
• Publication Number:
  US 20120042931A1
• Time in Patent Office: Days
• US Class Current: 136/246
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G02B 5/285 comprising deposited thin solid films G02B5/281 - G02B5/289 take precedence; multilayered film filters for fibre optic multiplexing G02B6/29361
• CPC Class Codes: H01L 31/02168 the coatings being antireflective or having enhancing optical properties for the solar cells
• CPC Class Codes: H01L 31/022425 for solar cells
• CPC Class Codes: Y02E 10/52 PV systems with concentrators

Abstract

An interferometric mask covering the front electrodes of a photovoltaic device is disclosed. Such an interferometric mask may reduce reflections of incident light from the electrodes. In various embodiments, the mask reduces reflections so that a front electrode pattern appears similar in color to adjacent regions of visible photovoltaic active material.

Claims

1. A device comprising:

a stack of thin films defining a static interferometric modulator, the stack including;

a reflective conductor;

an absorber; and

an optical resonant cavity between the reflective conductor and the absorber, wherein the optical resonant cavity includes a transparent conducting material.

2. The device of claim 1, wherein the transparent conducting material includes indium tin oxide.

3. The device of claim 1, wherein the reflective conductor is patterned so as to form a conductive line for carrying current.

4. The device of claim 3, wherein the device includes a photovoltaic active layer, and the conductive line forms an electrode on a front side of the photovoltaic active layer.

5. The device of claim 4, wherein the absorber is arranged on the front side of the conductive line.

6. The device of claim 4, wherein the electrode includes a bus electrode connecting a plurality of photovoltaic cells in an array.

7. The device of claim 4, wherein the electrode serves as a gridline electrode.

8. The device of claim 4, wherein the static interferometric modulator is configured such that a color of light reflected from the front side of the static interferometric modulator substantially matches a color of the photovoltaic active layer visible in regions adjacent the reflective conductor.

9. The device of claim 3, wherein the absorber is patterned to follow and cover the reflective conductor.

10. The device of claim 9, wherein the absorber is patterned to have a width coextensive with a width of the reflective conductor.

11. The device of claim 9, wherein the optical resonant cavity is patterned to follow and cover the reflective conductor.

12. The device of claim 11, wherein the optical resonant cavity and absorber are each patterned to be wider than the conductive line.

13. The device of claim 1, wherein the static interferometric modulator is configured such that little or no incident visible light is reflected from a front side of the static interferometric modulator and the static interferometric modulator appears black from a normal viewing angle.

14. The device of claim 1, wherein the static interferometric modulator is configured such that the reflectivity of the static interferometric modulator is less than 10%.

15. The device of claim 1, wherein the absorber includes a semitransparent thickness of metallic or semiconductor layers.

16. The device of claim 1, wherein the absorber includes at least one of:

chromium, molybdenum, titanium, silicon, tantalum, and tungsten.

17. The device of claim 1, wherein the absorber is formed on a substrate, the optical resonant cavity is formed on the absorber, and the reflective conductor is formed on the optical resonant cavity.

18. A method of manufacturing a device, the method comprising:

depositing an absorber on a substrate;

forming an optical resonant cavity over the absorber, wherein the optical resonant cavity includes a transparent conducting material;

disposing a reflective conductor over the optical resonant cavity; and

patterning the reflective conductor.

19. The method of claim 18, wherein the transparent conducting material includes indium tin oxide.

20. The method of claim 18, further comprising patterning the optical resonant cavity and the absorber.

21. The method of claim 20, wherein the optical resonant cavity and the absorber are patterned to follow the pattern of the reflector.

22. The method of claim 21, wherein patterning the reflective conductor includes defining the reflective conductor with a lithographic mask, and wherein the optical resonant cavity and absorber are patterned together with the reflective conductor.