The impact of nanoporous SiN_x interlayer growth position on high-quality GaN epitaxial films

The impact of nanoporous SiN x interlayer growth position on high-quality GaN epitaxial film was elucidated from the behavior of dislocations. The best quality GaN film was achieved when a nanoporous SiN x interlayer was grown on a rough layer, with the high-resolution X-ray diffraction rocking curve full width at half maximum for ( 1102 ) reflection decreasing to 223 arcs, and the total dislocation density reduced to less than 1.0×10 8 cm 2 . GaN films were grown on sapphire substrates by metal organic chemical vapor deposition. The quality of these films was investigated with high-resolution X-ray diffraction, atomic force microscopy, and cross-sectional transmission electron microscopy. A preference for the formation of half-loops to reduce threading dislocations was observed when an SiN x interlayer was grown on a rough layer. A growth mechanism is proposed to explain this preference.

The impact of nanoporous SiNx interlayer growth position on high-quality GaN epitaxial film was elucidated from the behavior of dislocations. The best quality GaN film was achieved when a nanoporous SiNx interlayer was grown on a rough layer, with the high-resolution X-ray diffraction rocking curve full width at half maximum for （ 1102 ） reflection decreasing to 223 arcs, and the total dislocation density reduced to less than 1.0xl08 cm-2. GaN films were grown on sapphire substrates by metal organic chem- ical vapor deposition. The quality of these films was investigated with high-resolution X-ray diffraction, atomic force microscopy, and cross-sectional transmission electron microscopy. A preference for the formation of half-loops to reduce threading dislocations was observed when an SiNx interlayer was grown on a rough layer. A growth mechanism is proposed to explain this preference.