Title :
Diffusion activation energy of cadmium in thin film CuInGaSe2
Author :
Biderman, N.J. ; Novak, Steven W. ; Laursen, T. ; Matyi, Richard J. ; Sundaramoorthy, R. ; Dufresne, Gary ; Wax, John ; Gardner, Michael ; Fobare, David ; Metacarpa, David ; Haldar, Pradeep ; Lloyd, J.R.
Author_Institution :
Coll. of Nanoscale Sci. & Eng. (CNSE), Univ. at Albany - SUNY, Albany, NY, USA
Abstract :
Diffusivity and activation energy of cadmium in copper indium gallium diselenide (CuInGaSe2 or CIGS) thin films were investigated by annealing solar-grade SLG/Mo/CIGS/CdS samples of two different CIGS thicknesses at temperatures between 150° C and 325° C. Diffusion profiles of cadmium volume and grain boundary were investigated by dual-beam time-of-flight secondary ion mass spectroscopy. A relationship between the cadmium´s volume and grain boundary diffusion coefficients and their activation energies at a given annealing temperature was established using LeClaire´s grain boundary diffusion model. The data also provide evidence that cadmium diffusion may be strongly modulated by a gallium gradient seen both laterally at the interface and in the bulk in solar-grade CIGS material.
Keywords :
annealing; cadmium compounds; copper compounds; diffusion; elemental semiconductors; gallium compounds; indium compounds; nuclear chemical analysis; photovoltaic cells; secondary ion mass spectroscopy; selenium compounds; semiconductor thin films; solar cells; ternary semiconductors; thin film devices; CuInGaSe2; LeClaire grain boundary diffusion model; cadmium diffusion activation energy; cadmium diffusivity; cadmium grain boundary diffusion coefficients; cadmium volume diffusion coefficients; copper indium gallium diselenide thin films; dual-beam time-of-flight secondary ion mass spectroscopy; solar-grade CIGS material; solar-grade sample annealing; Annealing; Cadmium; Gallium; Grain boundaries; Kinetic theory; Sputtering; activation energy; cadmium; diffusion processes; grain boundaries; grain size; photovoltaic cells; thin films;
Conference_Titel :
Photovoltaic Specialists Conference (PVSC), 2013 IEEE 39th
Conference_Location :
Tampa, FL
DOI :
10.1109/PVSC.2013.6744499
