Open AccessGrowth of low-defect-density nonpolar a-plane GaN on r-plane sapphire using pulse NH_3 interrupted etching
Author(s) -
Ji-Su Son,
Yoshio Honda,
Hiroshi Amano
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.003585
Subject(s) - sapphire , materials science , etching (microfabrication) , stacking fault , dislocation , optics , layer (electronics) , planar , optoelectronics , stacking , gallium nitride , wide bandgap semiconductor , laser , composite material , nuclear magnetic resonance , physics , computer graphics (images) , computer science
Nonpolar a-plane (11-20) GaN (a-GaN) layers with low overall defect density and high crystalline quality were grown on r-plane sapphire substrates using etched a-GaN. The a-GaN layer was etched by pulse NH3 interrupted etching. Subsequently, a 2-µm-thick Si-doped a-GaN layer was regrown on the etched a-GaN layer. A fully coalescent n-type a-GaN layer with a low threading dislocation density (~7.5 × 10(8) cm(-2)) and a low basal stacking fault density (~1.8 × 10(5) cm(-1)) was obtained. Compared with a planar sample, the full width at half maximum of the (11-20) X-ray rocking curve was significantly decreased to 518 arcsec along the c-axis direction and 562 arcsec along the m-axis direction.