Quantitative Determination of Grain Boundary Recombination Velocity in CdTe by Combination of Cathodoluminescence Measurements and Numerical Simulations

Conference · Sun Jun 14 04:00:00 EDT 2015

DOI:https://doi.org/10.1109/PVSC.2015.7355654· OSTI ID:1250661

Kanevce, Ana; Moseley, John; Kuciauskas, Darius; Al-Jassim, Mowafak; Metzger, Wyatt K.

We developed a 2D numerical model simulating cathodoluminescence (CL) measurements in CdTe. Using this model we analyze how various material parameters impact the CL contrast and intensity observed in the measured signal, and determine if and when we can accurately determine the value of grain boundary recombination rate. In addition to grain boundary (GB) recombination, the grain size and its ratio to the carrier diffusion length impact the results of the measurement. Holding the grain interior and GB recombination rates constant, we find that as the grain size increases and becomes larger than the diffusion length, the observed CL contrast is larger. In a small grain size material the surface recombination lowers the overall intensity of the signal, but does not impact the observed contrast significantly. In a large grain size material, high surface recombination velocity can lower the observed contrast in a measurement. This model in combination with an experiment is used to quantify the grain boundary recombination velocity in polycrystalline CdTe before and after the CdCl2 treatment.

• Research Organization: NREL (National Renewable Energy Laboratory (NREL), Golden, CO (United States))
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 1250661
• Report Number(s): NREL/CP-5J00-63547
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
CdTe
cathodoluminescence
grain boundaries
numerical simulations