[16a-A304-1~8] 13.9 Compound solar cells

▲ [16a-A304-6] Low-temperature photoluminescence investigation of p-type C-doped AlGaAs grown by MOVPE on vicinal substrates

〇Gan Li¹, Hassanet Sodabanlu², Maui Hino¹, Meita Asami¹, Kentaroh Watanabe², Masakazu Sugiyama^1,2, Yoshiaki Nakano¹ (1.The Univ. of Tokyo, 2.RCAST, the Univ. of Tokyo)

Keywords:AlGaAs, MOVPE, vicinal substrate

This paper studies AlGaAs double heterostructure (DH) samples grown on four types of GaAs substrates regarding their low-temperature photoluminescence (PL) results to analyze the dependencies of substrate orientations. Mutual comparison of the temperature dependence of PL intensity among samples gives us insight into how non-radiative recombination is enhanced in the temperature range above 20 K (1/T < 0.05). The quenching rate increases as the miscut angle increases, indicating the degraded crystal quality of AlGaAs with strong non-radiative recombination when grown on vicinal substrates. This observation was later validated by comparison of two solar cell devices grown on 2º-off and 5º-off substrates, respectively.