title: Utilization of native oxygen in Eu(RE)-doped GaN for enabling device compatibility in optoelectronic applications.
abstract: The detrimental influence of oxygen on the performance and reliability of V/III nitride based devices is well known. However, the influence of oxygen on the nature of the incorporation of other co-dopants, such as rare earth ions, has been largely overlooked in GaN. Here, we report the first comprehensive study of the critical role that oxygen has on Eu in GaN, as well as atomic scale observation of diffusion and local concentration of both atoms in the crystal lattice. We find that oxygen plays an integral role in the location, stability, and local defect structure around the Eu ions that were doped into the GaN host. Although the availability of oxygen is essential for these properties, it renders the material incompatible with GaN-based devices. However, the utilization of the normally occurring oxygen in GaN is promoted through structural manipulation, reducing its concentration by 2 orders of magnitude, while maintaining both the material quality and the favorable optical properties of the Eu ions. These findings open the way for full integration of RE dopants for optoelectronic functionalities in the existing GaN platform.
authors.affiliation: Department of Physics and Astronomy, University of Mount. Union, 1972 Clark Ave, Alliance, OH, 44601, USA.
authors.forename: B
authors.initials: B
authors.lastname: Mitchell
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: D
authors.initials: D
authors.lastname: Timmerman
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: J
authors.initials: J
authors.lastname: Poplawsky
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: W
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: D
authors.initials: D
authors.lastname: Lee
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Wakamatsu
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Takatsu
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Matsuda
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: W
authors.initials: W
authors.lastname: Guo
authors.affiliation: Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, P-2695-066 Bobadela LRS, Portugal.
authors.forename: K
authors.initials: K
authors.lastname: Lorenz
authors.affiliation: Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, P-2695-066 Bobadela LRS, Portugal.
authors.forename: E
authors.initials: E
authors.lastname: Alves
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Koizumi
authors.affiliation: Department of Physics and Astronomy, Lehigh University, 16 Memorial Dr. E, Bethlehem, PA, 18015, USA.
authors.forename: V
authors.initials: V
authors.lastname: Dierolf
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Fujiwara