Effect of annealing on interdigitated back contact silicon heterojunction solar cells(IBC)

Annealing effects have been studied on test structures and TLM pads to determine the optimum final annealing time for fabricated interdigitated back contact (IBC) solar cells. Initial results show that passivation will recover after 3 min annealing at 200 °C but will degrade by further annealing. Contact resistance measurement performed on TLM structures both for emitter and base stack show that by increasing the annealing time the contact resistance will increase. Using the initial annealing time of 5 min, we obtain a short circuit current density of 37 mA/cm
²
and open-circuit voltage of 691 mV, leading to a conversion efficiency of 19.3%.