Popis: |
The high temperature process at the 2nd stage of co-evaporation easily leads to the formation of the point defects such as Se vacancy and antisite defects in CIGS absorber layers. To passivate such defects, NaF post-deposition treatment (PDT) was carried out. After the NaF PDT at 300°C, Se vacancy and antisite defects were significantly reduced. In addition, out-diffusion of Cu to surface was suppressed, thereby improving the overall performance of CIGS thin film solar cells. Here, we report on the influence of NaF PDT on the defect chemistry as revealed by low-temperature photoluminescence (LT-PL) and X-ray photoelectron spectroscopy (XPS). |