Robin Nicholas

Abstract:

Using a modeling approach, InP lattice-matched InGaAs-based TPV cell structures were optimized as a function of the doping concentration and thickness of the active region. The devices were subsequently grown, fabricated and assessed. The modeling study shows that low doping concentrations for the active layers lead to an improved overall device performance as indicated by an increase of all the device parameters. The effect of the thickness of the active layers was investigated and indicates that relatively thin structures can be achieved within the optimal device parameters calculated. The variation of the device parameters as a function of the illumination conditions such as the black-body source temperature and incident intensity was also modeled and will be discussed. The device structures were grown on InP substrates using MOVPE and different doping concentrations and thicknesses were used. The devices were processed into mesa diodes and the device parameters extracted from the IN characteristics were compared and discussed in light of the modeling predictions.