Calcium as a nonradiative recombination center in InGaN. (13th January 2017) - Shen, Jimmy-Xuan
Abstract: Calcium can be unintentionally incorporated during the growth of semiconductor devices. Using hybrid functional first-principles calculations, we assess the role of Ca impurities in GaN. Ca substituted on the cation site acts as a deep acceptor with a level ∼1 eV above the GaN valence-band maximum. We find that for Ca concentrations of 10 17 cm −3, the Shockley–Read–Hall recombination coefficient, A, of InGaN exceeds 10 6 s −1 for band gaps less than 2.5 eV. A values of this magnitude can lead to significant reductions in the efficiency of light-emitting diodes.