title: Combinatorial Chemical Bath Deposition of CdS Contacts for Chalcogenide Photovoltaics.
abstract: Contact layers play an important role in thin film solar cells, but new material development and optimization of its thickness is usually a long and tedious process. A high-throughput experimental approach has been used to accelerate the rate of research in photovoltaic (PV) light absorbers and transparent conductive electrodes, however the combinatorial research on contact layers is less common. Here, we report on the chemical bath deposition (CBD) of CdS thin films by combinatorial dip coating technique and apply these contact layers to Cu(In,Ga)Se2 (CIGSe) and Cu2ZnSnSe4 (CZTSe) light absorbers in PV devices. Combinatorial thickness steps of CdS thin films were achieved by removal of the substrate from the chemical bath, at regular intervals of time, and in equal distance increments. The trends in the photoconversion efficiency and in the spectral response of the PV devices as a function of thickness of CdS contacts were explained with the help of optical and morphological characterization of the CdS thin films. The maximum PV efficiency achieved for the combinatorial dip-coating CBD was similar to that for the PV devices processed using conventional CBD. The results of this study lead to the conclusion that combinatorial dip-coating can be used to accelerate the optimization of PV device performance of CdS and other candidate contact layers for a wide range of emerging absorbers.
authors.affiliation: National Renewable Energy Laboratory , Golden, Colorado 80401, United States.|Indian Institute of Technology Bombay , Mumbai 400076, India.
authors.forename: Krishnaiah
authors.initials: K
authors.lastname: Mokurala
authors.affiliation: National Renewable Energy Laboratory , Golden, Colorado 80401, United States.|Colorado School of Mines , Golden, Colorado 80401, United States.
authors.forename: Lauryn L
authors.initials: LL
authors.lastname: Baranowski
authors.affiliation: National Renewable Energy Laboratory , Golden, Colorado 80401, United States.|Federal University of Sao Carlos , São Carlos-SP, 13565-905, Brazil.
authors.forename: Francisco W
authors.initials: FW
authors.lastname: de Souza Lucas
authors.affiliation: National Renewable Energy Laboratory , Golden, Colorado 80401, United States.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Siol
authors.affiliation: National Renewable Energy Laboratory , Golden, Colorado 80401, United States.
authors.forename: Maikel F A M
authors.initials: MF
authors.lastname: van Hest
authors.affiliation: Indian Institute of Technology Bombay , Mumbai 400076, India.
authors.forename: Sudhanshu
authors.initials: S
authors.lastname: Mallick
authors.affiliation: Indian Institute of Technology Bombay , Mumbai 400076, India.
authors.forename: Parag
authors.initials: P
authors.lastname: Bhargava
authors.affiliation: National Renewable Energy Laboratory , Golden, Colorado 80401, United States.
authors.forename: Andriy
authors.initials: A
authors.lastname: Zakutayev
mesh_terms: D000497:Alloys / Q000737:chemistry; D019187:Cadmium Compounds / Q000737:chemistry*; D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D004560:Electricity; D008027:Light; D012666:Semiconductors; D012993:Solar Energy; D013440:Sulfides / Q000737:chemistry*
chemical_list: D000497:Alloys; D019187:Cadmium Compounds; D013440:Sulfides; C034939:cadmium sulfide
keywords: CIGSe; CZTSe; buffer layer; current−voltage characteristics; external quantum efficiency; solar cells