(a) The free hole density as a function of position in the device and (b) the band diagram, under AM1.5 light and short-circuit conditions, for a HIT cell on N-type c-Si wafer at 300 K and 175 K, showing hole accumulation and virtual disappearance of the depletion region on the c-Si side of the amorphous-crystalline interface at 175 K; (c) the free hole density as a function of position under the same conditions and at the same temperatures for a standard P/N homo-junction c-Si solar cell.