US 11,817,516 B2
Photovoltaic devices and method of manufacturing
Dan Damjanovic, Perrysburg, OH (US); Markus Gloeckler, Perrysburg, OH (US); Feng Liao, Perrysburg, OH (US); Andrei Los, Perrysburg, OH (US); Dan Mao, Perrysburg, OH (US); Benjamin Milliron, Toledo, OH (US); Gopal Mor, Perrysburg, OH (US); Rick Powell, Ann Arbor, MI (US); Kenneth Ring, Waterville, OH (US); Aaron Roggelin, Millbury, OH (US); Jigish Trivedi, Perrysburg, OH (US); and Zhibo Zhao, Novi, MI (US)
Assigned to First Solar, Inc., Tempe, AZ (US)
Filed by First Solar, Inc., Tempe, AZ (US)
Filed on Oct. 25, 2019, as Appl. No. 16/664,737.
Application 16/664,737 is a division of application No. 14/602,340, filed on Jan. 22, 2015, granted, now 10,461,207.
Application 14/602,340 is a continuation of application No. 14/531,425, filed on Nov. 3, 2014, granted, now 10,529,883.
Prior Publication US 2020/0058818 A1, Feb. 20, 2020
Int. Cl. H01L 31/073 (2012.01); H01L 31/0224 (2006.01); H01L 31/0296 (2006.01); H01L 31/18 (2006.01); H01L 31/20 (2006.01)
CPC H01L 31/073 (2013.01) [H01L 31/0296 (2013.01); H01L 31/02966 (2013.01); H01L 31/022441 (2013.01); H01L 31/022466 (2013.01); H01L 31/1828 (2013.01); H01L 31/1832 (2013.01); H01L 31/1864 (2013.01); H01L 31/1884 (2013.01); H01L 31/208 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A method of forming a photovoltaic device comprising the steps of:
depositing a material comprising CdSe over a TCO layer;
depositing a material comprising CdTe over the material comprising CdSe to form a precursor;
annealing the precursor to form an absorber layer, whereby the material comprising CdSe and at least a portion of the material comprising CdTe interdiffuse to form a CdSeTe alloy;
depositing a material comprising tellurium and zinc, over the absorber layer, to form a back contact over the absorber layer; wherein:
the absorber layer is p-type;
a ratio of Te atoms to a sum of Se atoms and the Te atoms throughout the absorber layer is between about 99 to 100 and about 60 to 100; and
a Se concentration declines across a thickness of the absorber layer toward the back contact.