[22p-D316-1~16] 13.8 Optical properties and light-emitting devices

[22p-D316-14] Effect of Phosphorus Composition of barrier layers on Carrier Transport Properties in InGaAs/GaAsP Super Lattice Structures

〇Tetsuo Ikari¹, Ryo Furukawa¹, Naoki Yamamoto¹, Masakazu Sugiyama², Atsuhiko Fukuyama¹ (1.Univ. Miyazaki, 2.The Univ. Tokyo)

Keywords:Quantum structure solar device, nonradiative transition

Carrier collection efficiencies in InGaAs/GaAsP superlattice photovoltaic structures are increased by introducing a strain relaxation quantum layer. However, no insights are still observed from the viewpoint of the non-radiative transition. We investigate suitable phosphorous composition in barrier layers for optimizing photovoltaic conversion efficiency. Piezoelectric photothermal (PPT) and photoluminescence (PL) measurements were carried out as a function of temperature. We found that the activation energy for the non-radiative transition component had a maximum at the phosphorous concentration of 45%. This result is discussed in terms of a strain valance condition as well as an appearance of the indirect conduction band edge of GaAsP. Since no software can calculate the activation energy of the non-radiative process, the usefulness of the present PPT experimental methodology was also demonstrated.