Improved Device Models of CZTSe: nanolayer Ge solar cells with Quantum Efficiency

We fabricated and characterized CZTSe: nanolayer Ge (<;10 nm) thin film solar cells to quantitatively demonstrate an exact device model of quantum efficiency for Ge doped CZTSe devices. The linear electric field model is developed used to fit the unique quantum efficiency as compared to empirical data at forward bias condition. This model is characterized with a consistent set of parameters from a series of measurements and literature. Using the analytical modeling method, the carrier collection profile in the absorber is calculated and closely fitted by developed mathematical expressions to identify the carrier dynamics during the quantum efficiency measurement.