Numerical modeling and simulation of constant photocurrent method on a-Si p-i-n junction structure

We present modeling and simulation of the constant photocurrent method (CPM) measurements on a single p-i-n junction a-Si:H solar cell. Two types of D-states with Gaussian distribution were introduced for describing subbandgap absorption, originating from the electron transition from the D-states to the conduction band. The subbandgap absorption spectra obtained by CPM measurements on p-i-n a-Si:H solar cells are given by solving Poission´s equation, continuity equation, and current equation simultaneously. The effect of D-state characteristics on the subbandgap absorption coefficient spectra of p-i-n a-Si:H solar cells is investigated systematically