Aluminum-oxide-based inversion layer solar cells on n-type crystalline silicon: Fundamental properties and efficiency potential

作者：Werner Florian^*; Larionova Yevgeniya; Zielke Dimitri; Ohrdes Tobias; Schmidt Jan

来源：Journal of Applied Physics, 2014, 115(7): 073702.

DOI：10.1063/1.4865962

We introduce a rear-emitter inversion layer (IL) solar cell on n-type crystalline silicon (n-Si). The hole IL is induced by the high density of negative fixed charges in an aluminum oxide (Al2O3) surface passivation layer. For the formation of contacts to the inversion layer, we employ a single-step p(+) laser doping process, using aluminum from the Al2O3 layer as dopant source. Lateral hole transport through the IL underneath the n-Si/Al2O3 interface is analyzed by electrical measurements. The IL hole mobility is shown to be only marginally reduced by scattering at the high density of fixed charges at the n-Si/Al2O3 interface, resulting in an inversion layer sheet resistance of 15-18 k Omega/sq (in the dark). The effective sheet resistance of the IL is shown to decrease to below 4 k Omega/sq under solar cell operating conditions. Based on two-dimensional device simulations, we show that the proposed type of n-type silicon IL solar cell has a very high efficiency potential exceeding 26% including contact recombination losses.

• 出版日期2014-2-21