Temperature-dependent photoluminescence (TDPL), one of the most effective and powerful optical characterisation methods, is widely used to investigate carrier transport and localized states in semiconductor materials. Resonant excitation and non-resonant excitation are the two primary methods of researching this issue. In this study, the application ranges of the different excitation modes are ...

We have investigated the structure of non-polar GaN, both on the M - and A-plane, grown on LiGaO2 by plasma-assisted molecular beam epitaxy. The epitaxial relationship and the microstructure of the GaN films are investigated by transmission electron microscopy (TEM). The already reported epi-taxial relationship and for M -plane GaN is confirmed. The main defects are threading dislocations and s...

Combining through-focus high-resolution transmission electron microscopy and hierarchical multiscale simulations consisting of density-functional theory, analytical empirical potentials, and continuum elastic theory we demonstrate the existence of a new dislocation type in GaN. In contrast with all previously identified or suggested dislocation structures in GaN, all core atoms are fully coordi...

Ara A. Asatryan,1 Sergey A. Gredeskul,2,3 Lindsay C. Botten,1 Michael A. Byrne,1 Valentin D. Freilikher,4 Ilya V. Shadrivov,3 Ross C. McPhedran,5 and Yuri S. Kivshar3 1Department of Mathematical Sciences and Centre for Ultrahigh-Bandwidth Devices for Optical Systems (CUDOS), University of Technology, Sydney, New South Wales 2007, Australia 2Department of Physics, Ben Gurion University of the Ne...

P. S. Pershan,1 S. E. Stoltz,1 Oleg G. Shpyrko,2 Moshe Deutsch,3 Venkatachalapathy S. K. Balagurusamy,1 Mati Meron,4 Binhua Lin,4 and Reinhard Streitel1 1Department of Physics and SEAS, Harvard University, Cambridge, Massachusetts 02138, USA 2Department of Physics, University of California–San Diego, San Diego, La Jolla, California 92093, USA 3Department of Physics and Institute of Nanotechnolo...

あらまし GaN HEMTの高周波高出力の一例として X帯 50 W級,100 W級,並びに Ku帯 50 W級 GaN HEMT の技術課題と解決方法,特性例について述べる.GaN HEMT は出力電力密度が高い一方で,その発熱 密度も高い.発熱量を抑えるためには高い効率,そのために高い利得が必要である.X-Ku 帯において利得を上 げるために,フィールドプレートを用いない電流コラプス低減対策,Via-hole を用いたソース接地を適用した. その結果,X 帯 100 W 級 GaN HEMT では,飽和出力電力 51.1 dB(129 W),最大電力付加効率は 47.8%を 得た.Ku帯 50 W級 GaN HEMTでは,飽和出力電力 47.3 dBm(53 W),最大電力付加効率は 33.2%を得た. 最後にいくつかの実用例を紹介した. キーワード GaN HEMT,電力付加効...

Nicholas M. Kanaan,1,2,3 Gerardo A. Morfini,3,4* Nichole E. LaPointe,3,5 Gustavo F. Pigino,3,4 Kristina R. Patterson,1,3 Yuyu Song,3,4 Athena Andreadis,6 Yifan Fu,1 Scott T. Brady,3,4* and Lester I. Binder1* 1Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, 2Division of Translational Science and Molecular Medicine, College ...

The crystal quality and light output power of GaN-based light-emitting diodes (LEDs) grown on concave patterned sapphire substrate (CPSS) were investigated. It was found that the crystal quality of GaN-based LEDs grown on CPSS improved with the decrease of the pattern space (percentage of c-plane). However, when the pattern space decreased to 0.41 μm (S0.41-GaN), the GaN crystallinity dropped. ...