1110.1561 (James P. Connolly)

Analytical Models of Bulk and Quantum Well Solar Cells and Relevance of
the Radiative Limit    [PDF]

James P. Connolly

Bulk and quantum well solar cell analytical modelling is reviewed. The analytical approach allows explicit estimates of dominant generation and recombination mechanisms at work in charge neutral and space charge layers of the cells, and consistent analysis of light and dark characteristics leaves the Shockley-Read-Hall lifetime as single free parameter. Bulk PIN cells are shown to be inherently dominated by non radiative recombination as a result of the doping related non-radiative fraction of the Shockley injection currents. Quantum well PIN solar cells are shown to operate in the radiative limit as a result of the dominance of radiative recombination in the space charge region. These features are exploited using light trapping techniques leading to photon recycling and reduced radiative recombination. The conclusion is that the mirror backed quantum well solar cell device features open circuit voltages determined mainly by the higher bandgap neutral layers, with an absorption threshold determined by the lower gap quantum well superlattice.

View original: http://arxiv.org/abs/1110.1561