In-situ Cd-saturated growth of polycrystalline CdTe:As thin film was performed by metal organic chemical vapour deposition at a low temperature of 350 °C, to investigate the impact on As doping and device VOC. Device characterization showed conversion efficiency of ∼14%, and VOC of 772 mV, which is an improvement to the baseline device with CdTe:As absorber layer grown at 390 °C under non-saturated conditions. When the low temperature Cd-saturated growth was combined with chlorine heat treatment at a higher temperature of 440 °C (in contrast with the standard 420 °C) for 10 min, device efficiency improved to ∼17% with a high VOC of 877 mV. As a result, ∼100 mV boost in VOC from baseline is demonstrated with Cd-saturated CdTe:As device. Micro-photoluminescence and time-resolved photoluminescence measurements performed on these Cd-saturated CdTe:As devices confirmed that minority carrier lifetime significantly improved.
|Number of pages||7|
|Journal||IEEE Journal of Photovoltaics|
|Early online date||22 Aug 2022|
|Publication status||Published - 1 Nov 2022|