Quaternary chalcogenide wafers

• US 8,709,657 B2
• Filed: 12/09/2010
• Issued: 04/29/2014
• Est. Priority Date: 12/09/2010
• Status: Expired due to Fees

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Ionkin, Alex Sergey, Fish, Brian M.
• Primary Examiner(s): Choi, Ling-Siu
• Assistant Examiner(s): PEETS, MONIQUE R
• Application Number:
  US12/963,979
• Publication Number:
  US 20120145970A1
• Time in Patent Office: 1,237 Days
• Field of Search: 252/519.34, 439/478, 429/231.1, 429/218.1, 428/585
• US Class Current: 429/231.1
• CPC Class Codes: C30B 29/46 Sulfur-, selenium- or tellurium-containing compounds
• CPC Class Codes: C30B 9/00 Single-crystal growth from melt solutions using molten solvents by normal or gradient freezing C30B11/00; by zone-melting C30B13/00; by crystal pulling C30B15/00; on immersed seed crystal C30B17/00; by liquid phase epitaxial growth C30B19/00; under a protective fluid C30B27/00
• CPC Class Codes: C30B 9/12 Salt solvents, e.g. flux growth
• CPC Class Codes: Y10T 428/12285 Single taper [e.g., ingot, etc.]

Abstract

Disclosed herein are processes for making quaternary chalcogenide wafers. The process comprises heating a mixture of quaternary chalcogenide crystals and flux and then cooling the mixture to form a solidified mixture comprising ingots of quaternary chalcogenide and flux. The process also comprises isolating one or more ingots of quaternary chalcogenide from the solidified mixture and mounting at least one ingot in a polymer binder to form a quaternary chalcogenide-polymer composite. The process also comprises optionally slicing the quaternary chalcogenide-polymer composite to form one or more quaternary chalcogenide-polymer composite wafers. The quaternary chalcogenide wafers are useful for forming solar cells.

Claims

1. An article having a top surface and a bottom surface, the article comprising at least one quaternary chalcogenide ingot mounted in a non-conductive polymer binder, such that the at least one quaternary chalcogenide ingot is exposed on both the top surface and the bottom surface.

2. The article of claim 1, wherein the quaternary chalcogenide ingots are selected from the group consisting of Cu₂ZnSnS₄ (CZTS);

Cu₂ZnSnSe₄ (CZTSe); and

Cu₂ZnSn(S_a,Se_1-a)₄, where 0≦

a≦

1 (CZTS/Se).

3. The article of claim 1, wherein the polymer binder comprises an epoxy, an acrylic, polysiloxanes, or mixtures thereof.

4. The article of claim 1, wherein the article is in the form of a wafer.