1 eV Ga(NAsSb) grown by MOVPE using di-tertiary-butyl-arsano-amine (DTBAA)

N containing lattice matched 1 eV materials, such as Ga(NAsSb) and (GaIn)(NAs), are discussed as potential solar subcells in a four junction solar cell alongside Ge, GaAs, and (GaIn)P, reaching theoretically conversion efficiencies of around 50 %. The solar subcell with the highest conversion efficiency, consisting of (GaIn)(NAsSb), was grown with molecular beam epitaxy (MBE). The growth of Sb/N containing materials have always been a challenge to metalorganic vapor phase epitaxy (MOVPE), as N incorporation is hindered drastically by even small amounts of Sb if 1,1-dimethylhydrazine is used. This strong N/Sb interaction was not observed by MBE, therefore gas phase reactions in MOVPE are held responsible for the N incorporation drop. In this work we will present a systematic study of Ga(NAsSb) on GaAs grown in MOVPE with the novel N/As precursor di-tertiary-butyl-arsano-amine, as well as triethylgallium and triethylantimony. The achieved 1 eV Ga(NAsSb) material opens up new possibilities for using MOVPE to grow further solar subcells like (GaIn)(NAsSb) or Ga(NAsSb) in the band gap range of 1.0 – 1.1 eV.