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Title: High-efficiency, flexible CdTe solar cells on ultra-thin glass substrates

Flexible, high-efficiency, low-cost solar cells can enable applications that take advantage of high specific power, flexible form factors, lower installation and transportation costs. Here, we report a certified record efficiency of 16.4% for a flexible CdTe solar cell that is a marked improvement over the previous standard (14.05%). The improvement was achieved by replacing chemical-bath-deposited CdS with sputtered CdS:O and also replacing the high-temperature sputtered ZnTe:Cu back contact layer with co-evaporated and rapidly annealed ZnTe:Cu. We use quantum efficiency and capacitance-voltage measurements combined with device simulations to identify the reasons for the increase in efficiency. Both device simulations and experimental results show that higher carrier density can quantitatively account for the increased open circuit voltage (V{sub OC}) and Fill Factor (FF), and likewise, the increase in short circuit current density (J{sub SC}) can be attributed to the more transparent CdS:O.
Authors:
; ; ; ; ; ;  [1] ; ; ; ;  [2] ;  [3]
  1. National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)
  2. Colorado School of Mines, Golden, Colorado 80401 (United States)
  3. Corning, Inc., Corning, New York 14831 (United States)
Publication Date:
OSTI Identifier:
22398835
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 13; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANNEALING; CADMIUM SULFIDES; CADMIUM TELLURIDES; CAPACITANCE; CARRIER DENSITY; COMPUTERIZED SIMULATION; CURRENT DENSITY; ELECTRIC POTENTIAL; FILL FACTORS; FORM FACTORS; GLASS; LAYERS; QUANTUM EFFICIENCY; SOLAR CELLS; SPUTTERING; SUBSTRATES; ZINC TELLURIDES