We fabricated GaN-based light-emitting diodes (LEDs) without pre-activation of p-type GaN. During the fabrication process, a 100-nm-thick indium tin oxide film was served as the p-type contact layer and annealed at 500°C in N2 ambient for 20 min to increase its transparency as well as to activate the p-type GaN. The electrical measurements showed that the LEDs were featured by a lower forward voltage and higher wall-plug efficiency in comparison with LEDs using pre-activation of p-type GaN. We discussed the mechanism of activation of p-type GaN at 500°C in N2 ambient. Furthermore, x-ray photoemission spectroscopy examinations were carried out to study the improved electrical performances of the LEDs without pre-activation of p-type GaN.
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http://dx.doi.org/10.1186/s11671-015-0792-8 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Clean Energy Research Center, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan.
Thermoelectric (TE) devices recycle high-temperature waste-heat efficiently, but waste-heat below sub-250 °C remains uncaptured. As promoting full autonomy for the Internet of Things (IoT), we present a TE generator using multilayered pseudo--type GaN/TiN/GaN and -type TiO/TiN/TiO TE one-leg devices, where heterozygous of outer/inner layers demonstrates the functions of a colossal Seebeck coefficient ( = +15,000 μV K) with phonon-assist hopping, controlling by the porosity for reducing thermal conductivity (κ), a high electric conductivity (σ) with reducing κ by outer layers, and σ- coexistence over singular curve by the asymmetric electrode configuration. is elucidated hopping among inner grains and the space charge (SC) grain boundary (GB) of 100 μm regions within Debye length.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Jiangxi Provincial Key Laboratory of Advanced Electronic Materials and Devices, Jiangxi Science & Technology Normal University, Nanchang 330018, China.
Owing to their high light absorption coefficient, excellent electronic mobility, and enhanced excitonic effect, two-dimensional (2D) GaN materials hold great potential for applications in optoelectronic and electronic devices. As the metal-semiconductor junction (MSJ) is a fundamental component of semiconductor-based devices, identifying a suitable metal for contacting semiconductors is essential. In this work, detailed first-principles calculations were performed to investigate the contact behavior between the GaN monolayer (ML) and a series of 2D metals MX (M = Nb, Ta, V, Mo, or W; X = S or Se).
View Article and Find Full Text PDFSmall
January 2025
Key Laboratory of UV Light Emitting Materials and Technology, Ministry of Education, Northeast Normal University, Changchun, 130024, China.
In this study an (AlGa)O barrier layer is inserted between β-GaO and GaN in a p-GaN/n-GaO diode photodetector, causing the dark current to decrease considerably, and device performance to improve significantly. The β-GaO/β-(AlGa)O/GaN n-type/Barrier/p-type photodetector achieves a photocurrent gain of 1246, responsivity of 237 A W, and specific detectivity of 5.23 × 10 cm Hz W under a bias of -20 V.
View Article and Find Full Text PDFZhonghua Gan Zang Bing Za Zhi
January 2025
Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, Hefei230022, China NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract (Anhui Medical University), Hefei230032, China Engineering Research Center of Biopreservation and Artificial Organs, Ministry of Education, Hefei230032, China Key Laboratory of Population Health Across Life Cycle (Anhui Medical University), Ministry of Education of the People's Republic of China, Hefei230032, China Anhui Province Key Laboratory of Reproductive Disorders and Obstetrics and Gynecology Diseases, Hefei230032, China Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei230032, China Anhui Provincial Institute of Translational Medicine, Hefei230032, China.
Hepatolenticular degeneration, also known as Wilson's disease, is a type of autosomal recessive genetic disorder of copper metabolism. The causative gene, ATP7B, is located on the long arm of chromosome 13 and encodes a P-type ATPase that is involved in copper transport. Pathogenic mutations in the ATP7B gene sequence lead to the diminished or lost function of the ATP7B protein, resulting in pathological copper deposition in organs such as the liver, brain, kidneys, and cornea.
View Article and Find Full Text PDFNanotechnology
January 2025
Department of Nanoscale Science and Engineering, SUNY-Albany, Albany, NY 12203, United States of America.
GaN is an important semiconductor for energy-efficient light-emitting devices. Hydrogen plays a crucial role in gallium nitride (GaN) growth and processing. It can form electrically neutral complexes with acceptors during growth, which significantly increases the acceptor incorporation.
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