GaN and AlN layers grown by nano epitaxial lateral overgrowth technique on porous substrates

Conference · Sat Jul 01 04:00:00 EDT 2000

OSTI ID:20104526

Mynbaeva, M; Titkov, A; Kryzhanovski, A ^[1]

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1. and others

Defect density and stress reduction in heteroepitaxial GaN and AlN materials is one of the main issues in group III nitride technology. Recently, significant progress in defect density reduction in GaN layers has been achieved using lateral overgrowth technique. In this paper, the authors describe a novel technique based on nano-scale epitaxial lateral overgrowth. GaN layers were overgrown by hydride vapor phase epitaxy (HVPE) on porous GaN. Porous GaN was formed by anodization of GaN layers grown previously on SiC substrates. Pore's size was in nano-scale range. Thickness of overgrown layers ranged from 2 to 120 microns. It was shown that GaN layers overgrown on porous GaN have good surface morphology and high crystalline quality. The surface of overgrown GaN material was uniform and flat without any traces of porous structure. Raman spectroscopy measurements indicated that the stress in the layers grown directly on 6H-SiC substrates remains at its usual level of about 1.3 GPa. Preliminary experiments were done on HVPE growth of AlN layer on porous substrates. Improvement of surface morphology and crack density reduction has been observed.

• Research Organization: Ioffe Inst., St. Petersburg (RU)
• Sponsoring Organization: INTAS Foundation; Office of Naval Research
• OSTI ID: 20104526
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM NITRIDES
CRYSTAL DEFECTS
DATA
GALLIUM NITRIDES
MICROSTRUCTURE
MORPHOLOGY
POROSITY
STRESSES
SUBSTRATES
VAPOR PHASE EPITAXY