Abstract
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.
Original language | American English |
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Number of pages | 4 |
DOIs | |
State | Published - 14 Dec 2015 |
Event | 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC) - New Orleans, Louisiana Duration: 14 Jun 2015 → 19 Jun 2015 |
Conference
Conference | 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC) |
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City | New Orleans, Louisiana |
Period | 14/06/15 → 19/06/15 |
Bibliographical note
Publisher Copyright:© 2015 IEEE.
NREL Publication Number
- NREL/CP-5J00-63547
Keywords
- cathodoluminescence
- CdTe
- grain boundaries
- numerical simulations