Kevin L Dobson

US Patent:

20070151862, Jul 5, 2007

Filed:

Dec 15, 2006

Appl. No.:

11/611717

Inventors:

Kevin Dobson - Newark DE, US
M. Calixto - Mexico City, MX
Brian McCandless - Elkton MD, US
Robert Birkmire - Newark DE, US

International Classification:

C25D 5/48
C25D 3/58
H01L 31/00

US Classification:

205220000, 205239000, 136262000, 136264000, 136265000

Abstract:

Single bath electrodeposition of polycrystalline Cu(In,Ga)Sethin films for photovoltaic applications is disclosed. Specifically, Cu(In,Ga)Sewas deposited onto Mo electrodes from low concentration buffered (pH 2.5) aqueous baths containing CuCl, InCl, GaCland HSeO. Moreover, buffered aqueous baths are disclosed wherein Se/Cu concentration ratios were controlled to optimize Se and Cu levels, while In concentration was adjusted to control deposited In and Ga. Further disclosed are pre- and post-deposition processing methods resulting in smooth, compact, crack-free films of near stoichiometric values. Post deposition heat treatments on electrodeposited CuInSe-based films in selenium and sulfur containing atmosphere are described. CuInSe-based films from a single bath deposited onto Mo electrodes from low concentration aqueous baths. Heat treatment of electrodeposited Cu(In,Ga)Sein HSe producing an O-free crystalline film and annealing in Se-vapor producing crystalline CuInSewithout loss of Ga or O).