TY - JOUR
T1 - Investigation of oxygen and other impurities and their effect on the transparency of a Na flux grown GaN crystal
AU - Abo Alreesh, Mohammed
AU - Von Dollen, Paul
AU - Malkowski, Thomas F.
AU - Mates, Tom
AU - Albrithen, Hamad
AU - DenBaars, Steven
AU - Nakamura, Shuji
AU - Speck, James S.
N1 - KAUST Repository Item: Exported on 2022-06-09
Acknowledgements: This work was supported by the KACST-KAUST-UCSB Solid State Lighting Program (SSLP). The authors acknowledge the use of the Microfluidics Laboratory within the California NanoSystems Institute, supported by the University of California, Santa Barbara and the University of California, Office of the President. The authors acknowledge the use of the MRL Shared Experimental Facilities which are supported by the MRSEC Program of the NSF under Award No. DMR 1720256; a member of the NSF-funded Materials Research Facilities Network (www.mrfn.org).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
PY - 2019/1/3
Y1 - 2019/1/3
N2 - In this study, we investigate several impurities in bulk GaN crystals grown by the sodium flux technique. In our system, black GaN is in general associated with oxygen, sodium, and molybdenum concentrations in excess of 1019 atoms/cm3. Here, we report on the correlation of high levels of oxygen with opaque crystals. Samples that contain oxygen concentrations above 1019 atoms/cm3 are highly absorbing regardless of the presence of other impurities. Experiments with partially submerged seeds indicated material grown mainly above the nominal liquid surface was more transparent and had a generally lower impurity concentration, especially oxygen. In optically transparent regions, concentrations of oxygen, sodium, and carbon were as low as 7 × 1016, 2 × 1016, and 5 × 1016 atoms/cm3, respectively, while the concentration of molybdenum was below the detection limit.
AB - In this study, we investigate several impurities in bulk GaN crystals grown by the sodium flux technique. In our system, black GaN is in general associated with oxygen, sodium, and molybdenum concentrations in excess of 1019 atoms/cm3. Here, we report on the correlation of high levels of oxygen with opaque crystals. Samples that contain oxygen concentrations above 1019 atoms/cm3 are highly absorbing regardless of the presence of other impurities. Experiments with partially submerged seeds indicated material grown mainly above the nominal liquid surface was more transparent and had a generally lower impurity concentration, especially oxygen. In optically transparent regions, concentrations of oxygen, sodium, and carbon were as low as 7 × 1016, 2 × 1016, and 5 × 1016 atoms/cm3, respectively, while the concentration of molybdenum was below the detection limit.
UR - http://hdl.handle.net/10754/678816
UR - https://linkinghub.elsevier.com/retrieve/pii/S0022024818306304
UR - http://www.scopus.com/inward/record.url?scp=85059376001&partnerID=8YFLogxK
U2 - 10.1016/j.jcrysgro.2018.12.018
DO - 10.1016/j.jcrysgro.2018.12.018
M3 - Article
SN - 0022-0248
VL - 508
SP - 50
EP - 57
JO - Journal of Crystal Growth
JF - Journal of Crystal Growth
ER -