Characterisation of selected GaAs thin film photovoltaic structures for concentrators

The molecular beam epitaxy is considered to be suitable method for preparat ion of efficient GaAs solar cells. This paper deals with GaAs p/i/n solar c ell structures prepared with different thickness of intrinsic i-region. The current-voltage characteristics in the dark and the performance under stan dard simulated light spectra and concentrated light were investigated. The dielectric properties at the frequency range from 50 Hz to 1 MHz and at dif ferent temperatures were investigated, as well. Preliminary results on full y processed 1 cm x 1 cm p/i/n GaAs solar cells have shown an increase in ma ximum power output by a factor of around 2.7 to 3.0 under concentrated illu mination of 5 Suns. This work is being carried out as a part of an effort t o fabricate efficient multiple quantum well GaAs cells based on thin film s tructures.