The initial motivation for the University of Delaware/Georgia Institute of Technology project was the then-newly discovered bandgap of InN, which was re-measured at ~0.7 eV, rather than the previous 1.9 eV. This made InGaN a potential material for solar cells with the possibility of absorbing 99% of the solar irradiance. The advantages of the InGaN material system are the wide range of direct bandgap, high absorption coefficient, a low effective mass...