ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Planar m-plane GaN was grown on (1100) m-plane 6H-SiC substrates usinghigh-temperature AlN nucleation layers by metalorganic chemical vapor deposition. Scanningelectron microscopy (SEM) and atomic force microscopy (AFM) images showed striated features onthe sample surface aligned along the GaN [1120] direction, which are perpendicular to thoseassociated with (1120) a-plane GaN. The epitaxial relationship between the m-GaN and 6H-SiC wasanalyzed using high-resolution x-ray diffraction (XRD). In order to reduce the defect density,epitaxial lateral overgrowth (ELO) was carried out on an m-GaN template with mask stripes along theGaN [1120] direction, which makes the lateral growth fronts advance along the GaN c-axis. On-axisXRD rocking curves show that the full width at half maximum (FWHM) values for the ELO sampleswere reduced by nearly half when compared to those of the m-plane template without ELO. Clearatomic steps were observed in the wing regions by AFM. The absence of the striated features that areassociated with the template could be indicative of the reduction of basal stacking faults in the ELOwings. Low-temperature photoluminescence (PL) spectra showed an excitonic emission at 3.47eV, abasal stacking fault (BSF)-related emission at 3.41 eV, and other defect-related emissions at 3.29 eVand 3.34 eV
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/20/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.600-603.1273.pdf
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