• Monemar, B.
• Hommel, D.
• Figge, S.
• Tutor, M.
• Paskova, T.
• Hanser, A.
• Williams, Nikki
• Darakchieva, V.
• Kroeger, R.

Abstract

<p>Thick GaN bars with [1120] orientation have been sliced from GaN boules grown on freestanding films by hydride vapor phase epitaxy (HVPE) in the [0001] direction. High-resolution x-ray diffraction and transmission electron microscopy have been used to study the structural quality and defect distribution in the material in comparison to heteroepitaxially grown thick HVPE-GaN films grown in the [1120] direction on (1102)-plane sapphire. It is demonstrated that while the heteroepitaxial material possesses a high density of stacking faults and partial dislocations, leading to anisotropic structural characteristics, the (1120)-plane bulk GaN, sliced from boules, exhibits low dislocation density and narrow rocking curves with isotropic in-plane character. (c) 2006 American Institute of Physics.</p>

Topics

• density
• impedance spectroscopy
• phase
• x-ray diffraction
• anisotropic
• transmission electron microscopy
• dislocation
• isotropic
• stacking fault