Article
Crystallography
Srinivas Gandrothula, Haojun Zhang, Pavel Shapturenka, Ryan Anderson, Matthew S. Wong, Hongjian Li, Takeshi Kamikawa, Shuji Nakamura, Steven P. DenBaars
Summary: Research showed that edge-emitting laser diodes fabricated on a reduced dislocation density epitaxial lateral overgrown wing can achieve laser action. Two types of facet feasibility studies were conducted, with results showing that facet LDs formed on wafers through reactive ion etching demonstrated laser action.
Article
Crystallography
Yingnan Huang, Jianxun Liu, Xiujian Sun, Xiaoning Zhan, Qian Sun, Hongwei Gao, Meixin Feng, Yu Zhou, Hui Yang
Summary: We report on the epitaxial lateral overgrowth (ELO) of high-quality AlN on stripe-patterned Si(111) substrates with various trench widths. By narrowing down the trench and ridge widths of patterned Si substrates, crack-free, 6-micrometer-thick, high-quality AlN films on Si substrates were produced. This work paves the way for the fabrication of high-performance Al(Ga)N-based thin-film devices on Si.
Article
Nanoscience & Nanotechnology
Yaqi Gao, Jiankun Yang, Xiaoli Ji, Rui He, Jianchang Yan, Junxi Wang, Tongbo Wei
Summary: In this study, high-quality semipolar AlGaN epitaxial films were successfully obtained on m-plane sapphire substrates by metal-organic chemical vapor deposition. The fabricated semipolar AlGaN metal-semiconductor-metal solar-blind ultraviolet photodetector exhibited high responsivity and fast response, with significantly reduced dark current through a simple wet chemical etching method. This work shows potential for the development of high-performance solar-blind ultraviolet photodetectors.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Wenlong Li, Lianshan Wang, Ruohao Chai, Ling Wen, Zhen Wang, Wangguo Guo, Huanhua Wang, Shaoyan Yang
Summary: This study used metal-organic chemical vapor deposition (MOCVD) to grow (11 (2) over bar2) InGaN/GaN superlattice templates with different periodic InGaN layer thicknesses on m-plane sapphire substrates. The strain, relaxation mechanism, and the influence of strain relaxation on the semipolar superlattice templates were investigated. The results showed that the strain in the superlattice templates was anisotropic and increased with increasing InGaN thickness. The strain relaxation was associated with the formation of one-dimensional misfit dislocation arrays in the superlattice structure.
Article
Chemistry, Multidisciplinary
Andreea Bianca Serban, Vladimir Lucian Ene, Doru Dinescu, Iulia Zai, Nikolay Djourelov, Bogdan Stefan Vasile, Victor Leca
Summary: Various aspects of the GaN/AlN/SiC heterostructure, such as growth relations, interface consistency, and elemental diffusion, were studied using HR-TEM, HR-XRD, and DBS. Comparisons with previous work on Si and Al2O3 substrates revealed higher crystal quality and dislocation densities for GaN grown on SiC. The effective positron diffusion length for the GaN layer was also found to be higher using DBS measurements.
Article
Materials Science, Multidisciplinary
P. V. Seredin, N. S. Buylov, D. L. Goloshchapov, S. A. Ivkov, E. P. Matyukhina, I. N. Arsentyev, A. V. Nashchekin, Sh. Sh. Sharofidinov, A. M. Mizerov, E. V. Pirogov, M. S. Sobolev
Summary: In this study, we investigated the effects of a non-polar m-plane sapphire substrate on the properties of HVPE growth and the characteristics of the GaN epitaxial film. We successfully obtained high-quality semipolar GaN samples on the m-sapphire substrate and determined their structural and optical properties. The optimization of the technological methodology may present a promising approach for the growth of high-quality GaN structures on large area m-sapphire substrates.
Article
Materials Science, Multidisciplinary
Ramasis Goswami, Syed Qadri, Neeraj Nepal, Charles Eddy
Summary: In this study, ultra-thin AlN films were grown on different substrates using atomic layer epitaxy, showing that the substrate, particularly the strain, plays a crucial role in determining the crystal structure of AlN films. The strain level varied significantly depending on the substrate, impacting the orientation relation and crystal quality of AlN films.
Article
Materials Science, Multidisciplinary
Wenlong Li, Lianshan Wang, Ruohao Chai, Ling Wen, Haixia Lu, Huanhua Wang, Shaoyan Yang, Wenhong Sun
Summary: Additional high-temperature nitridation can improve the crystalline quality of semipolar (1122) GaN epitaxial films, reducing surface roughness and anisotropy.
CURRENT APPLIED PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Li Chen, Wei Lin, Hangyang Chen, Houqiang Xu, Chenyu Guo, Zhibin Liu, Jianchang Yan, Jie Sun, Huan Liu, Jason Wu, Wei Guo, Junyong Kang, Jichun Ye
Summary: This work investigates the growth of semipolar AlN thin films on m-plane sapphire substrates using a hierarchical growth mode, and the effects of thermal annealing and regrowth on the evolution of defects in AlN. The study found that extended defects turned into partial dislocations after high-temperature treatment, leading to improved crystalline quality in the AlN regrowth layer. High-temperature annealing and regrowth processes were demonstrated to be stable and repeatable techniques for high-efficiency semipolar UV semiconductor devices.
CRYSTAL GROWTH & DESIGN
(2021)
Article
Crystallography
Narihito Okada, Kazuyuki Tadatomo
Summary: This study reports the growth and characterization of thick, completely relaxed {11-22}-oriented InGaN layers using epitaxial lateral overgrowth (ELO). The results show that the performance of ELO-InGaN on InGaN templates is significantly better than that of non-ELO InGaN.
Article
Materials Science, Multidisciplinary
Omar Al-Zuhairi, Afiq Anuar, Abdullah Haaziq Ahmad Makinudin, Ahmad Shuhaimi Abu Bakar, M. N. Azlan, Azzuliani Supangat
Summary: In this study, the effect of varying biscyclopentadienyl magnesium flow rate on the growth of p-type gallium nitride thin films was investigated. The results show that using an optimized flux of 30 standard cubic centimeter per minute significantly reduces grain size and improves crystallinity. Additionally, the mobility and carrier concentrations were enhanced with the use of moderate biscyclopentadienyl magnesium flow rate.
Article
Engineering, Electrical & Electronic
Muhammad Saddique Akbar Khan, Hui Liao, Guo Yu, Imran Iqbal, Menglai Lei, Rui Lang, Zehan Mi, Huanqing Chen, Hua Zong, Xiaodong Hu
Summary: Two innovative techniques, serpentine channel pattern sapphire substrate (SCPSS) and InGaN interlayer (IL), are proposed to effectively reduce threading dislocations (TDs) in GaN-based devices. Experimental results demonstrate the effectiveness of these techniques in decreasing the number of TDs and improving material quality.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
E. Jelmakas, A. Kadys, M. Dmukauskas, T. Grinys, R. Tomasiunas, D. Dobrovolskas, G. Gervinskas, S. Juodkazis, M. Talaikis, G. Niaura
Summary: This study presents a systematic investigation of the GaN epitaxial lateral overgrowth (ELO) on a patterned sapphire substrate using focused ion beam (FIB) technology. Arrays of varying sizes and shapes of trenches were grown and analyzed to understand the correlation between trench size, array geometry, and epitaxial layer thickness. The study demonstrated that a homogeneous overgrowth of the entire array was observed for arrays with the largest trenches and reduced intertrench distance.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Haixia Lu, Lianshan Wang, Yao Liu, Shuping Zhang, Yanlian Yang, Vishal Saravade, Zhe Chuan Feng, Benjamin Klein, Ian T. Ferguson, Lingyu Wan, Wenhong Sun
Summary: This study reports on the structural and optical properties of polar GaN on c-plane sapphire substrates and semi-polar GaN films on m-plane sapphire substrates. The results show that polar GaN has higher crystal quality and lower surface roughness compared to semi-polar GaN. The biaxial structural stress in GaN switches with increasing temperature, with a higher stress-switch temperature in GaN/c-plane than in GaN/m-plane. Only polar GaN exhibits yellow-emissions in addition to ultraviolet emissions. Raman spectroscopy-related oscillations show systematic variations with temperature in both polar and semi-polar GaN configurations. This research provides valuable insights into the characterization of GaN with different crystal polarities.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Georg Schoenweger, Adrian Petraru, Md Redwanul Islam, Niklas Wolff, Benedikt Haas, Adnan Hammud, Christoph Koch, Lorenz Kienle, Hermann Kohlstedt, Simon Fichtner
Summary: This paper presents the first in-depth structural and electrical characterization of all-epitaxial, all-wurtzite-type ferroelectric III-N semiconductor heterostructures. The results show that Al1-xScxN films have multiple strain states and exhibit splitting of the ferroelectric displacement current into separate peaks. It is also observed that films grown on the metal-polar GaN template feature an initial multidomain state.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Physics, Applied
Christopher X. Ren, Fengzai Tang, Rachel A. Oliver, Tongtong Zhu
JOURNAL OF APPLIED PHYSICS
(2018)
Article
Physics, Applied
N. Khalid, J. -Y. Kim, A. Ionescu, T. Hussain, F. Oehler, T. Zhu, R. A. Oliver, I. Farrer, R. Ahmad, C. H. W. Barnes
JOURNAL OF APPLIED PHYSICS
(2018)
Article
Physics, Applied
H. P. Springbett, K. Gao, J. Jarman, T. Zhu, M. Holmes, Y. Arakawa, R. A. Oliver
APPLIED PHYSICS LETTERS
(2018)
Article
Chemistry, Physical
Peter Griffin, Tongtong Zhu, Rachel Oliver
Article
Nanoscience & Nanotechnology
Kevin T. P. Lim, Callum Deakin, Boning Ding, Xinyu Bai, Peter Griffin, Tongtong Zhu, Rachel A. Oliver, Dan Credgington
Article
Physics, Applied
Kang Gao, Helen Springbett, Tongtong Zhu, Rachel A. Oliver, Yasuhiko Arakawa, Mark J. Holmes
APPLIED PHYSICS LETTERS
(2019)
Article
Physics, Applied
John C. Jarman, Tongtong Zhu, Peter H. Griffin, Rachel A. Oliver
JAPANESE JOURNAL OF APPLIED PHYSICS
(2019)
Article
Physics, Applied
Fengzai Tang, Tongtong Zhu, Wai-Yuan Fu, Fabrice Oehler, Siyuan Zhang, James T. Griffiths, Colin Humphreys, Tomas L. Martin, Paul A. J. Bagot, Michael P. Moody, Saroj Kanta Patra, Stefan Schulz, Philip Dawson, Stephen Church, Janet Jacobs, Rachel A. Oliver
JOURNAL OF APPLIED PHYSICS
(2019)
Article
Nanoscience & Nanotechnology
Minh Nguyen, Tongtong Zhu, Mehran Kianinia, Fabien Massabuau, Igor Aharonovich, Milos Toth, Rachel Oliver, Carlo Bradac
Article
Physics, Applied
P. H. Griffin, M. Frentrup, T. Zhu, M. E. Vickers, R. A. Oliver
JOURNAL OF APPLIED PHYSICS
(2019)
Article
Physics, Applied
P. H. Griffin, K. M. Patel, T. Zhu, R. M. Langford, V. S. Kamboj, D. A. Ritchie, R. A. Oliver
JOURNAL OF APPLIED PHYSICS
(2020)
Article
Nanoscience & Nanotechnology
Fabien C. -P. Massabuau, Peter H. Griffin, Helen P. Springbett, Yingjun Liu, R. Vasant Kumar, Tongtong Zhu, Rachel A. Oliver
Article
Nanoscience & Nanotechnology
M. J. Holmes, T. Zhu, F. C. -P. Massabuau, J. Jarman, R. A. Oliver, Y. Arakawa
Summary: High-purity pulsed single-photon emission has been measured from an InGaN quantum dot, showing promising potential for application in quantum key distribution systems.
Article
Physics, Applied
C. C. Kocher, T. J. Puchtler, J. C. Jarman, T. Zhu, T. Wang, L. Nuttall, R. A. Oliver, R. A. Taylor
APPLIED PHYSICS LETTERS
(2017)
Article
Physics, Applied
Tong Wang, Tim J. Puchtler, Tongtong Zhu, John C. Jarman, Claudius C. Kocher, Rachel A. Oliver, Robert A. Taylor
APPLIED PHYSICS LETTERS
(2017)