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.