Premium
Complete orientational access for semipolar GaN devices on sapphire (Phys. Status Solidi B 1/2016)
Author(s) -
Leung Benjamin,
Wang Dili,
Kuo YuSheng,
Han Jung
Publication year - 2016
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.201670503
Subject(s) - sapphire , materials science , optoelectronics , light emitting diode , chemical mechanical planarization , diode , gallium nitride , planar , enhanced data rates for gsm evolution , plane (geometry) , optics , nanotechnology , layer (electronics) , computer science , physics , laser , geometry , telecommunications , computer graphics (images) , mathematics
The complete freedom to choose the surface orientation of GaN has been an elusive goal for growth on sapphire substrates. As opposed to bulk GaN substrates, which can be arbitrarily sliced at any orientations, the growth on planar sapphire substrates is constrained to only several discrete orientations. For high efficiency, low droop light‐emitting diodes, the surface with the best demonstrated LEDs has been a moving target, and on planes within the continuous angular‐orientation space not demonstrated as of yet on sapphire substrates. In their Feature Article on pp. 23–35 , Leung et al. review the advances in high performance semipolar and nonpolar GaN LEDs, providing guidance on the desired GaN surfaces. A complete process is then demonstrated to enable these unique orientations of GaN using sapphire substrates. In particular, electrically injected (20‐21) GaN LEDs are fabricated on sapphire by the use of stripe‐patterned substrates, inclined c ‐plane GaN growth and a chemical‐mechanical planarization. Finally, the complete range of orientations is shown to be opened by the demonstration of an orientation ( hkil ), where l < 0, namely (20‐2‐1) GaN on sapphire, which has been achieved here for the first time.