학술논문
Spatially and spectrally resolved defects in polycrystalline CdTe thin films revealed by quantitative cathodoluminescence
Document Type
Conference
Source
2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) Photovoltaic Specialists Conference (PVSC), 2019 IEEE 46th. 2:1-4 Jun, 2019
Subject
Language
Abstract
Increasing the grain size is a potential strategy to reduce grain-boundary recombination and improve performance of thin-film solar cells. Here, CdTe thin films with a range of grain sized were produced by varying the CdC1 2 post-deposition treatment temperature. We use high-resolution cathodoluminescence (CL) microscopy to study recombination and shallow defect levels in detail. Intensities from room temperature CL maps were compared across samples. We find that the CL intensity initially increases with grain size, as expected, but then plateaus as the grain size is increased further. The plateau is correlated with a decrease in the characteristic length-related to the carrier diffusion length-determined from CL intensity profiles near grain boundaries. In addition, low-temperature CL measurements demonstrate the evolution of the defect levels with CdC1 2 temperature.