Abstract
We conducted cathodoluminescence (CL) spectrum imaging and electron backscatter diffraction on the same microscopic areas of CdTe thin films to correlate grain-boundary (GB) recombination by GB "type." We examined misorientation-based GB types, including coincident site lattice (CSL) Σ=3, other-CSL (Σ=5-49), and general GBs (Σ>49), which make up ∼47%-48%, ∼6%-8%, and ∼44%-47%, respectively, of the GB length at the film back surfaces. Statistically averaged CL total intensities were calculated for each GB type from sample sizes of ≥97 GBs per type and were compared to the average grain-interior CL intensity. We find that only ∼16%-18% of Σ=3 GBs are active non-radiative recombination centers. In contrast, all other-CSL and general GBs are observed to be strong non-radiative centers and, interestingly, these GB types have about the same CL intensity. Both as-deposited and CdCl2-treated films were studied. The CdCl2 treatment reduces non-radiative recombination at both other-CSL and general GBs, but GBs are still recombination centers after the CdCl2 treatment.
Original language | American English |
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Article number | 025702 |
Number of pages | 9 |
Journal | Journal of Applied Physics |
Volume | 118 |
Issue number | 2 |
DOIs | |
State | Published - 14 Jul 2015 |
Bibliographical note
Publisher Copyright:© 2015 AIP Publishing LLC.
NREL Publication Number
- NREL/JA-5K00-64338
Keywords
- cathodoluminescence (CL) spectroscopy
- geographic information systems (GIS)
- grain boundaries (GBS)
- II-VI semiconductors
- structure
- thin films