A5015740284- GaN-based semiconductor devices and materials
- Luminescence Properties of Advanced Materials
- ZnO doping and properties
- Ga2O3 and related materials
- Chemical Synthesis and Characterization
- Ammonia Synthesis and Nitrogen Reduction
- Solid-state spectroscopy and crystallography
- Perovskite Materials and Applications
- Semiconductor materials and devices
- Radiation Detection and Scintillator Technologies
- Gas Sensing Nanomaterials and Sensors
- Acoustic Wave Resonator Technologies
- Optical Coatings and Gratings
- Inorganic and Organometallic Chemistry
- Zeolite Catalysis and Synthesis
- Plasma Diagnostics and Applications
- Semiconductor Quantum Structures and Devices
Koito Manufacturing (Japan)
2012-2019
Shimizu (Japan)
2017
We report a K2CaPO4F:Eu2+ phosphor with new crystal structure. This has large Stokes shift and converts near-ultraviolet light to red luminescence without absorption of other visible light. The mechanism was elucidated by applying constrained density functional theory the solved
We report novel white light-emitting diode (WLED) devices that improve emission color uniformity. The WLEDs consist of a violet chip and mixed-phosphor layer three phosphors previously developed by us. It is found each phosphor does not reabsorb the luminescence from other phosphors; consequently, get affected mounted quantity and/or variation in wavelength. Furthermore, an encapsulated WLED with hemispherical dome-shaped enables area to be irradiated uniform color, producing excellent...
We demonstrated how annealing of the sputtered AlN buffer layer (sp‐AlN) on r ‐plane sapphire could be used to produce a high‐crystalline‐quality GaN ( ‐GaN). The sp‐AlN with large grains was confirmed by at 1600 °C in N 2 ambient, consequently its crystalline orientation and quality were significantly improved. Moreover, it found that ‐GaN grown annealed showed better quality, including reduction basal stacking fault density, than untreated (as sputtered). implication is growth method using...
High luminescence efficiency is obtained in halide- and chalcogenide-based phosphors, but they are impractical because of their poor chemical durability. Here we report a halide-based nanocomposite phosphor with excellent sufficient durability for practical use. Our approach was to disperse luminescent single nanocrystals CaI2:Eu2+ chemically stable, translucent crystalline SiO2 matrix. Using this approach, successfully prepared by means self-organization through simple solid-state reaction....
Typical multi quantum well (MQW) grown on nonpolar a-plane GaN templates shows many pits composed of several semipolar planes, and these emit at different wavelengths due to the variation indium incorporations into QW. In this study, a surface-recovery layer high-temperature barrier were introduced improve MQW quality. We succeeded in decreasing prior growth improving interfaces MQW. The structural optical properties significantly improved.
Nonpolar a-plane GaN (a-GaN) grown on r-plane sapphire substrate is one of the promising materials for eliminating an internal field in III-nitride devices. Thus, a high performance light-emitting diode can be expected by using crystalline quality a-GaN. In our study, we realized a-GaN both patterned (PSS) and sputtered AlN buffer layer (sp-AlN). The PSS had conical patterns with diameter 900 nm height 600 nm. placed triangular arrangement interval 1000 30-nm-thick sp-AlN was deposited at...