Energy Band Profile Optimization of the Emitter for High Efficiency c-Si Heterojunction Solar Cell

AFORS-HET was utilized to explore the optimized energy band profile of the emitter(p) for the c-Si(n) based heterojunction solar cell. To obtain high efficiency, the valence band maximum level (E
_V
) of the emitter should be lower than that of the c-Si base. When the valence band offset |ΔE
_V
| = 0.4 eV, the doping activation energy (E
_a
) of the emitter can be as high as about 0.36 eV. Except for this, E
_a
should be reduced to lower E
_f
. The conduction band minimum level (E
_C
) of the emitter should be at least 0.2 eV higher than that of the c-Si base.