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51.
Kageyama T. Miyamoto T. Makino S. Ikenaga Y. Nishiyama N. Matsutani A. Koyama F. Iga K. 《Electronics letters》2001,37(4):225-226
The authors present a near 1200 nm wavelength vertical-cavity surface-emitting laser (VCSEL) the active region of which is formed by GaInNAs/GaAs quantum wells grown by chemical beam epitaxy. Room temperature continuous-wave operation has been demonstrated with a high slope efficiency of 0.23 W/A, a high output power of over 1.0 mW, and a singlemode output power of 0.34 mW. The fabricated devices with different aperture sizes show low threshold currents of 1.2-2.1 mA and a record low threshold current density of 2.6 kA/cm2 in GaInNAs VCSELs 相似文献
52.
本文对免疫酶组织化学的样品制备程序和染色方法做了详细的阐述。用直接法、间接法和ABC法,对人小肠免疫酶的定位,进行了光镜和电镜的观察,染色阳性反应显著,获得了满意的效果。并对染色技巧做了分析和探讨。 相似文献
53.
Soshi Sato Kuniyuki Kakushima Parhat Ahmet Kenji Ohmori Kenji Natori Keisaku Yamada Hiroshi Iwai 《Microelectronics Reliability》2011,51(5):879-884
We have experimentally demonstrated structural advantages due to rounded corners of rectangular-like cross-section of silicon nanowire (SiNW) field-effect transistors (FETs) on on-current (ION), inversion charge density normalized by a peripheral length of channel cross-section (Qinv) and effective carrier mobility (μeff). The ION was evaluated at the overdrive voltage (VOV) of 1.0 V, which is the difference between gate voltage (Vg) and the threshold voltage (Vth), and at the drain voltage of 1.0 V. The SiNW nFETs have revealed high ION of 1600 μA/μm of the channel width (wNW) of 19 nm and height (hNW) of 12 nm with the gate length (Lg) of 65 nm. We have separated the amount of on-current per wire at VOV = 1.0 V to a corner component and a flat surface component, and the contribution of the corners was nearly 60% of the total ION of the SiNW nFET with Lg of 65 nm. Higher Qinv at VOV = 1.0 V evaluated by advanced split-CV method was obtained with narrower SiNW FET, and it has been revealed the amount of inversion charge near corners occupied 50% of all the amount of inversion charge of the SiNW FET (wNW = 19 nm and hNW = 12 nm). We also obtained high μeff of the SiNW FETs compared with that of SOI planar nFETs. The μeff at the corners of SiNW FET has been calculated with the separated amount of inversion charge and drain conductance. Higher μeff around corners is obtained than the original μeff of the SiNW nFETs. The higher μeff and the large fractions of ION and Qinv around the corners indicate that the rounded corners of rectangular-like cross-sections play important roles on the enhancement of the electrical performance of the SiNW nFETs. 相似文献
54.
Haigui Yang Masatoshi Iyota Shogo Ikeura Dong Wang Hiroshi Nakashima 《Solid-state electronics》2011,60(1):128-133
A method of Al2O3 deposition and subsequent post-deposition annealing (Al2O3-PDA) was proposed to passivate electrically active defects in Ge-rich SiGe-on-insulator (SGOI) substrates, which were fabricated using Ge condensation by dry oxidation. The effect of Al2O3-PDA on defect passivation was clarified by surface analysis and electrical evaluation. It was found that Al2O3-PDA could not only suppress the surface reaction during Al-PDA in our previous work [Yang H, Wang D, Nakashima H, Hirayama K, Kojima S, Ikeura S. Defect control by Al-deposition and the subsequent post-annealing for SiGe-on-insulator substrates with different Ge fractions. Thin Solid Films 2010; 518: 2342-5.], but could also effectively passivate p-type defects generated during Ge condensation. The concentration in the range of 1016-1018 cm−3 for defect-induced acceptors and holes in Ge-rich SGOI drastically decreased after Al2O3-PDA. As a result of defect passivation, the electrical characteristics of both back-gate p-channel and n-channel metal-oxide-semiconductor field-effect transistors fabricated on Ge-rich SGOI were greatly improved after Al2O3-PDA. 相似文献
55.
Hiroyuki Yamada Atsushi Tsurumaki‐Fukuchi Masaki Kobayashi Takuro Nagai Yoshikiyo Toyosaki Hiroshi Kumigashira Akihito Sawa 《Advanced functional materials》2015,25(18):2708-2714
Tunnel electroresistance in ferroelectric tunnel junctions (FTJs) has attracted considerable interest, because of a promising application to nonvolatile memories. Development of ferroelectric thin‐film devices requires atomic‐scale band‐structure engineering based on depolarization‐field effects at interfaces. By using FTJs consisting of ultrathin layers of the prototypical ferroelectric BaTiO3, it is demonstrated that the surface termination of the ferroelectric in contact with a simple‐metal electrode critically affects properties of electroresistance. BaTiO3 barrier‐layers with TiO2 or BaO terminations show opposing relationships between the polarization direction and the resistance state. The resistance‐switching ratio in the junctions can be remarkably enhanced up to 105% at room temperature, by artificially controlling the fraction of BaO termination. These results are explained in terms of the termination dependence of the depolarization field that is generated by a dead layer and imperfect charge screening. The findings on the mechanism of tunnel electroresistance should lead to performance improvements in the devices based on nanoscale ferroelectrics. 相似文献
56.
3D Micromolding of Arrayed Waveguide Gratings on Upconversion Luminescent Layers for Flexible Transparent Displays without Mirrors,Electrodes, and Electric Circuits 下载免费PDF全文
Satoshi Watanabe Takeo Asanuma Takafumi Sasahara Hiroshi Hyodo Mutsuyoshi Matsumoto Kohei Soga 《Advanced functional materials》2015,25(28):4390-4396
A new technique for the fabrication of arrayed waveguide gratings on upconversion luminescent layers for flexible transparent displays is reported. Ho3+‐ and Yb3+‐codoped NaYF4 nanoparticles are synthesized by hydrothermal techniques. Transparent films consisting of two transparent polymers on the NaYF4 nanoparticle films exhibit mechanical flexibility and high transparence in visible region. Patterned NaYF4 nanoparticle films are fabricated by calcination‐free micromolding in capillaries. Arrayed waveguide gratings consisting of the two transparent polymers are formed on the patterned NaYF4 nanoparticle films by micromolding in capillaries. Green and red luminescence is observed from the upconversion luminescent layers of the NaYF4 nanoparticle films in the arrayed waveguide gratings under excitation at 980 nm laser light. Arrayed waveguide gratings on the upconversion luminescent layers are fabricated with Er3+‐doped NaYF4 nanoparticles which can convert two photons at 850 and 1500 nm into single photon at 550 nm. These results demonstrate that flexible transparent displays can be fabricated by constructing arrayed waveguide gratings on upconversion luminescent layers, which can operate in nonprojection mode without mirrors, transparent electrodes, and electric circuits. 相似文献
57.
Flexible Electronics: 3D Micromolding of Arrayed Waveguide Gratings on Upconversion Luminescent Layers for Flexible Transparent Displays without Mirrors,Electrodes, and Electric Circuits (Adv. Funct. Mater. 28/2015) 下载免费PDF全文
58.
Bisanthracene‐Based Donor–Acceptor‐type Light‐Emitting Dopants: Highly Efficient Deep‐Blue Emission in Organic Light‐Emitting Devices 下载免费PDF全文
Jian‐Yong Hu Yong‐Jin Pu Fumiya Satoh So Kawata Hiroshi Katagiri Hisahiro Sasabe Junji Kido 《Advanced functional materials》2014,24(14):2064-2071
Deep‐blue fluorescent compounds are particularly important in organic light‐emitting devices (OLEDs). A donor–accepotor (DA)‐type blue‐emitting compound, 1‐(10‐(4‐methoxyphenyl)anthracen‐9‐yl)‐4‐(10‐(4‐cyanophenyl)anthracen‐9‐yl)benzene ( BD3 ), is synthesized, and for comparison, a nonDA‐type compound, 1,4‐bis(10‐phenylanthracene‐9‐yl)benzene ( BD1 ) and a weak DA‐type compound, 1‐(10‐phenylanthracen‐9‐yl)‐4‐(10‐(4‐cyanophenyl)anthracen‐9‐yl)‐benzene ( BD2 ), are also synthesized. The twisted conformations of the two anthracene units in the compounds, confirmed by single crystal X‐ray analysis, effectively prevent π‐conjugation, and the compound shows deep‐blue photoluminescence (PL) with a high PL quantum efficiency, almost independent of the solvent polarity, resulting from the absence of an intramolecular charge transfer state. The DA‐type molecule BD3 in a non‐doped device exhibits a maximum external quantum efficiency (EQE) of 4.2% with a slight roll‐off, indicating good charge balance due to the DA‐type molecular design. In the doped device with 4,4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl (CBP) host, the BD3 exhibits higher EQE than 10% with Commission International de L'Eclairge (CIE) coordinates of (0.15, 0.06) and a narrow full‐width at half‐maximum of 45 nm, which is close to the CIE of the high definition television standard blue. 相似文献
59.
Tsutomu Kanno Hiromasa Tamaki Masato Yoshiya Hiroshi Uchiyama Sachiko Maki Masaki Takata Yuzuru Miyazaki 《Advanced functional materials》2021,31(13):2008469
Mg3Sb2-based intermetallic compounds with exceptionally high thermoelectric performance exhibit unconventional n-type dopability and anomalously low thermal conductivity, attracting much attention to the underlying mechanisms. To date, investigations have been limited to first-principle calculations and thermodynamic analysis of defect formation, and detailed experimental analysis on crystal structure and phonon modes has not been achieved. Here, a synchrotron X-ray diffraction study clarifies that, against a previous view of a simple crystal structure with a small unit cell, Mg3Sb2 is inherently a heavily disordered material with Frenkel defects, charge-neutral defect complexes of cation vacancies and interstitials. Ionic charge neutrality preserved in Mg3Sb2 is responsible for exotic n-type dopability, which is unachievable for other Zintl phase materials. The thermal conductivity of Mg3Sb2 exhibits deviation from the standard T−1 temperature dependency with strongly limited phonon transport due to a strain field. Inelastic X-ray scattering measurement reveals enhanced phonon scattering induced by disorder. The results will draw renewed attention to crystal defects and disorder as means to explore new high-performance thermoelectric materials. 相似文献
60.
Hiroshi Hiroshima 《Microelectronic Engineering》2009,86(4-6):611-614
Pattern density variation is uncomfortable for nanoimprint lithography which uses a moldable material supplied as a thin film, because the variation of pattern density causes variations of residual layer thickness reflecting on the local pattern density. To solve the problem, a new type of mold “capacity-equalized mold”, which has constant averaged depth regardless of pattern density, was fabricated and the structure of the mold was inspected. UV nanoimprint was then carried out using the mold and thickness and uniformity of the residual layer were investigated. An average thickness of 33.2 nm with a standard deviation of 3.4 nm was obtained for the mold pattern layout with a pattern density of from 0.25 to 0.75. It was found that a standard deviation of 1.2 nm was achieved for pattern density variation of from 0.33 to 0.67 by excluding artifacts. 相似文献