Method and structure for forming module using a powder coating and thermal treatment process

• US 8,440,903 B1
• Filed: 02/17/2009
• Issued: 05/14/2013
• Est. Priority Date: 02/21/2008
• Status: Expired due to Fees

• Current Assignee: Stion Corporation
• Original Assignee: Stion Corporation
• Inventors: Farris, Chester A. III
• Primary Examiner(s): Michener, Jennifer
• Assistant Examiner(s): Danicic, Christopher
• Application Number:
  US12/372,722
• Time in Patent Office: 1,547 Days
• Field of Search: None
• US Class Current: 136/251
• CPC Class Codes: H01L 31/02167 for solar cells
• CPC Class Codes: H01L 31/048 Encapsulation of modules
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

The present invention provides a solar module formed using a powder coating and thermal treatment process. The solar module includes a substrate having a surface region and a photovoltaic material overlying the surface region. The solar module further includes a barrier material overlying the photovoltaic material. Moreover, the solar module includes a coating overlying the barrier material and enclosing the photovoltaic material to mechanically protect the photovoltaic material. In certain embodiments, photovoltaic material is a thin film photovoltaic cell and the coating is provided by a powder coating substantially free of bubbles formed by electrostatic spraying and cured with a thermal treatment process.

Claims

1. A method of forming a solar module, the method comprising:

providing a substrate member having a surface region;

forming a photovoltaic film overlying the surface region, the photovoltaic film comprising one or more layers of N-type photosensitive semiconductor material alternatively and respectively overlying one or more layers of P-type photosensitive semiconductor material;

forming a barrier layer overlying and enclosing the photovoltaic film on the top and side surfaces;

forming a powder coating overlying the barrier layer and enclosing the photovoltaic film to protect the photovoltaic film, wherein the powder coating consists of a tetrafluorooxetane fluorine-doped SnO₂;

performing a thermal treatment process to cure the powder coating; and

sealing with an encapsulating material over the powder coating wherein the barrier layer comprises SiN, or SiO2, or TiN, or TFO.

2. The method of claim 1 wherein the forming a photovoltaic film overlying the surface region comprises at least a process selected from a deposition, a chemical reaction, a painting, a printing, a spraying, sputtering, and a plating.

3. The method of claim 1 wherein the P-type or N-type photosensitive material comprises silicon or germanium, or compound semiconductor of group III-V or II-VI, or copper indium diselenide (CIS), or Copper Indium Gallium Selenide (CIGS), or Cadmium Telluride (CdTe), or metal oxide bearing semiconductor material, or nanostructured material.

4. The method of claim 1 wherein forming the powder coating is performed at a temperature from room temperature to less than 500 Degrees Celsius.

5. The method of claim 1 wherein the powder coating comprises a thickness ranging from about 10 nm to about 3 mm.

6. The method of claim 1 wherein forming a powder coating overlying the barrier layer comprises using an electrostatic nozzle to spray a plurality of charged powder particles on the substrate being electrically grounded.

7. The method of claim 1 wherein performing the thermal treatment process comprises a temperature ranging from 100 to 400 Degrees Celsius applied for 10 minutes or less, so that the cured powder coating is substantially free of bubbles and pin-holes.

8. The method of claim 1 wherein the encapsulating material comprises one or more materials selected from EVA, PVA, paint, reflowable glass, or sol gel.