Calcium as a nonradiative recombination center in InGaN. (13th January 2017)

• Record Type: Journal Article
• Authors: Shen, Jimmy-Xuan; Wickramaratne, Darshana; Dreyer, Cyrus E.; Alkauskas, Audrius; Young, Erin; Speck, James S.; Van de Walle, Chris G.
• Is Part Of: Applied physics express. Volume 10:Number 2(2017)
• Publication Date: 2017-01-13
• Subjects: Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.7567/APEX.10.021001
• Languages: English
• ISSNs: 1882-0778

Abstract

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.