Influence of TMAl preflow on AlN epitaxy on sapphire

Handle URI:
http://hdl.handle.net/10754/623481
Title:
Influence of TMAl preflow on AlN epitaxy on sapphire
Authors:
Sun, Haiding ( 0000-0001-8664-666X ) ; Wu, Feng; Park, Young Jae; Al tahtamouni, T. M. ( 0000-0002-8149-2945 ) ; Li, Kuang-Hui; Alfaraj, Nasir ( 0000-0002-0429-9439 ) ; Detchprohm, Theeradetch; Dupuis, Russell D. ( 0000-0003-4691-1208 ) ; Li, Xiaohang ( 0000-0002-4434-365X )
Abstract:
The trimethylaluminum (TMAl) preflow process has been widely applied on sapphire substrates prior to growing Al-polar AlN films by metalorganic chemical vapor deposition. However, it has been unclear how the TMAl preflow process really works. In this letter, we reported on carbon's significance in the polarity and growth mode of AlN films due to the TMAl preflow. Without the preflow, no trace of carbon was found at the AlN/sapphire interface and the films possessed mixed Al- and N-polarity. With the 5 s preflow, carbon started to precipitate due to the decomposition of TMAl, forming scattered carbon-rich clusters which were graphitic carbon. It was discovered that the carbon attracted surrounding oxygen impurity atoms and consequently suppressed the formation of AlxOyNz and thus N-polarity. With the 40 s preflow, the significant presence of carbon clusters at the AlN/sapphire interface was observed. While still attracting oxygen and preventing the N-polarity, the carbon clusters served as randomly distributed masks to further induce a 3D growth mode for the AlN growth. The corresponding epitaxial growth mode change is discussed.
KAUST Department:
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division; Electrical Engineering Program
Citation:
Influence of TMAl preflow on AlN epitaxy on sapphire 2017, 110 (19):192106 Applied Physics Letters
Publisher:
AIP Publishing
Journal:
Applied Physics Letters
Issue Date:
12-May-2017
DOI:
10.1063/1.4983388
Type:
Article
ISSN:
0003-6951; 1077-3118
Sponsors:
The KAUST authors would like to acknowledge the support of GCC Research Program REP/1/3189-01-01, Baseline BAS/1/1664-01-01, and Equipment BAS/1/1664-01-07. The work at QU was supported by GCC Research Program GCC-2017–007. The work at Georgia Institute of Technology was supported in part by DARPA under Grant No. W911NF-15-1-0026 and NSF under Grant No. DMR-1410874. R.D.D. acknowledges the additional support of the Steve W. Chaddick Endowed Chair in Electro-Optics and Georgia Research Alliance.
Additional Links:
http://aip.scitation.org/doi/10.1063/1.4983388
Appears in Collections:
Articles

Full metadata record

DC FieldValue Language
dc.contributor.authorSun, Haidingen
dc.contributor.authorWu, Fengen
dc.contributor.authorPark, Young Jaeen
dc.contributor.authorAl tahtamouni, T. M.en
dc.contributor.authorLi, Kuang-Huien
dc.contributor.authorAlfaraj, Nasiren
dc.contributor.authorDetchprohm, Theeradetchen
dc.contributor.authorDupuis, Russell D.en
dc.contributor.authorLi, Xiaohangen
dc.date.accessioned2017-05-14T06:58:09Z-
dc.date.available2017-05-14T06:58:09Z-
dc.date.issued2017-05-12-
dc.identifier.citationInfluence of TMAl preflow on AlN epitaxy on sapphire 2017, 110 (19):192106 Applied Physics Lettersen
dc.identifier.issn0003-6951-
dc.identifier.issn1077-3118-
dc.identifier.doi10.1063/1.4983388-
dc.identifier.urihttp://hdl.handle.net/10754/623481-
dc.description.abstractThe trimethylaluminum (TMAl) preflow process has been widely applied on sapphire substrates prior to growing Al-polar AlN films by metalorganic chemical vapor deposition. However, it has been unclear how the TMAl preflow process really works. In this letter, we reported on carbon's significance in the polarity and growth mode of AlN films due to the TMAl preflow. Without the preflow, no trace of carbon was found at the AlN/sapphire interface and the films possessed mixed Al- and N-polarity. With the 5 s preflow, carbon started to precipitate due to the decomposition of TMAl, forming scattered carbon-rich clusters which were graphitic carbon. It was discovered that the carbon attracted surrounding oxygen impurity atoms and consequently suppressed the formation of AlxOyNz and thus N-polarity. With the 40 s preflow, the significant presence of carbon clusters at the AlN/sapphire interface was observed. While still attracting oxygen and preventing the N-polarity, the carbon clusters served as randomly distributed masks to further induce a 3D growth mode for the AlN growth. The corresponding epitaxial growth mode change is discussed.en
dc.description.sponsorshipThe KAUST authors would like to acknowledge the support of GCC Research Program REP/1/3189-01-01, Baseline BAS/1/1664-01-01, and Equipment BAS/1/1664-01-07. The work at QU was supported by GCC Research Program GCC-2017–007. The work at Georgia Institute of Technology was supported in part by DARPA under Grant No. W911NF-15-1-0026 and NSF under Grant No. DMR-1410874. R.D.D. acknowledges the additional support of the Steve W. Chaddick Endowed Chair in Electro-Optics and Georgia Research Alliance.en
dc.language.isoenen
dc.publisherAIP Publishingen
dc.relation.urlhttp://aip.scitation.org/doi/10.1063/1.4983388en
dc.rightsArchived with thanks to Applied Physics Lettersen
dc.subjectSapphireen
dc.subjectAlN filmsen
dc.subjectThin film growthen
dc.subjectIII-V semiconductorsen
dc.subjectEpitaxyen
dc.titleInfluence of TMAl preflow on AlN epitaxy on sapphireen
dc.typeArticleen
dc.contributor.departmentComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Divisionen
dc.contributor.departmentElectrical Engineering Programen
dc.identifier.journalApplied Physics Lettersen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionGeorgia Institute of Technologyen
dc.contributor.institutionQatar Universityen
dc.contributor.affiliationKing Abdullah University of Science and Technology (KAUST)en
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