The Markov behavior in PERC solar cells based on transient photovoltage process

The Passivated Emitter and Rear Cell (PERC) structures were widely applied in the p-Type silicon solar cell with the advancement of technology. However, the behaviors of carriers in PECRC bulks were difficult to be predicted due to the Brownian movement and scattering. Here, we have simulated the charge behaviors of PERC based on the Markov Chain in a transient and open circuit (OC) condition. In OC condition, charge carriers were jumped among various states without exporting to external circuit. Hence, the Markov Chain can be used to predict the probability of carriers in various states and then give an expectation of voltage dynamic. In the experimental result, it can be seen that the tendency of voltage was well fixed with the simulation under thermal equilibrium (T=300 K) condition. Once the equilibrium was broken by the thermal injection, the increasement of deep-level traps will accelerate the recombination rate. This work can also be applied in other field such as photo detectors and light emitting diodes (LEDs) to predict the charge behaviors.