Front electrode for use in photovoltaic device and method of making same

• US 8,076,571 B2
• Filed: 09/19/2008
• Issued: 12/13/2011
• Est. Priority Date: 11/02/2006
• Status: Active Grant

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: den Boer, Willem, Lu, Yiwei, Broadway, David, Corsner, Bryce
• Primary Examiner(s): Ridley, Basia
• Assistant Examiner(s): Bernier, Lindsey
• Application Number:
  US12/232,619
• Publication Number:
  US 20090084438A1
• Time in Patent Office: 1,180 Days
• Field of Search: 136/243, 136/256, 136/252, 136/260, 136/258, 136/261, 136/265, 136/264
• US Class Current: 136/265
• CPC Class Codes: H01L 31/02168 the coatings being antireflective or having enhancing optical properties for the solar cells
• CPC Class Codes: H01L 31/022466 made of transparent conductive layers, e.g. TCO, ITO layers
• CPC Class Codes: H01L 31/022475 composed of indium tin oxide [ITO]
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

This invention relates to a front electrode/contact for use in an electronic device such as a photovoltaic device. In certain example embodiments, the front electrode of a photovoltaic device or the like includes a multilayer coating including at least one transparent conductive oxide (TCO) layer (e.g., of or including a material such as tin oxide, ITO, zinc oxide, or the like) and/or at least one conductive substantially metallic IR reflecting layer (e.g., based on silver, gold, or the like). In certain example instances, the multilayer front electrode coating may include one or more conductive metal(s) oxide layer(s) and/or one or more conductive substantially metallic IR reflecting layer(s) in order to provide for reduced visible light reflection, increased conductivity, cheaper manufacturability, and/or increased infrared (IR) reflection capability.

Claims

1. A photovoltaic device including a front electrode structure, the front electrode structure comprising:

a front substantially transparent glass substrate;

a dielectric layer comprising titanium oxide;

a dielectric layer comprising silicon oxynitride, wherein the layer comprising titanium oxide is located between the glass substrate and the layer comprising silicon oxynitride;

a conductive layer comprising indium tin oxide, wherein the layer comprising silicon oxynitride is located between and contacting at least the layer comprising indium tin oxide and the layer comprising titanium oxide;

a conductive layer comprising at least one of zinc oxide, tin oxide, and/or zinc aluminum oxide, wherein the conductive layer comprising indium tin oxide is located between and directly contacting the layer comprising silicon oxynitride and the conductive layer comprising at least one of zinc oxide, tin oxide, and/or zinc aluminum oxide;

wherein the front electrode structure comprising said layer comprising titanium oxide, said layer comprising silicon oxynitride, said conductive layer comprising indium tin oxide, and said conductive layer comprising at least one of zinc oxide, tin oxide, and/or zinc aluminum oxide, is provided on an interior surface of the front glass substrate facing a semiconductor film of the photovoltaic device.

2. The photovoltaic device of claim 1, further comprising another layer comprising silicon oxynitride and/or silicon nitride between the glass substrate and the layer comprising titanium oxide.

3. The photovoltaic device of claim 1, wherein an exterior surface of the glass substrate is etched, but the interior surface of the glass substrate on which the layer stack is provided is not etched and is substantially flat.

4. The photovoltaic device of claim 1, wherein the semiconductor film comprises silicon, and the front electrode structure has a transmission of at least 85% in at least a majority of a range of from 450-700 nm.

5. The photovoltaic device of claim 1, wherein the semiconductor film comprises silicon, and the front electrode structure has a transmission of at least 87% in at least part of a range of from 450-700 nm.

6. The photovoltaic device of claim 1, wherein the semiconductor film comprises CdS and/or CdTe, and the front electrode structure has a transmission of at least 90% in at least a majority of a range of from 500-600 nm.

7. The photovoltaic device of claim 1, wherein the semiconductor film comprises CdS and/or CdTe, and the front electrode structure has a transmission of at least 92% in at least part of a range of from 500-600 nm.

8. The photovoltaic device of claim 1, wherein the semiconductor film contacts the conductive layer comprising at least one of zinc oxide, tin oxide, and/or zinc aluminum oxide.

9. The photovoltaice device of claim 8, wherein the semiconductor film comprises CdS and/or CdTe.