The research of post-treatment on Cd_1-xMgxTe thin films and CdTe solar cells

As for it higher band gap, Cd_1-xMg_xTe (CMT) material has been taken into consideration to improve the open-circuit voltage of CdTe solar cells as an electron reflector layer. An essential step in the development of this new interlayer is the passivation process. X-ray Diffraction (XRD) and scanning electron microscope (SEM) results give us the suitable annealing temperature range of CMT thin films from 350°C to 400°C, and suggest that the annealing process is beneficial to grain growth and recrystallization. The concentration of CdCl₂ solution has an influence on the crystallinity of the thin films and coating method would contribute to electrical performance of the devices. The CMT/CdTe cells which underwent the two-step annealing procedure at high purity nitrogen atmosphere showed the significant improvements in device performance. Furthermore, the CdTe solar cells with the CdTe cap layer and Te/Cu back contacts also demonstrated higher performance.