The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper describes a comparative study of Ni/Au and Pd/Au ohmic contacts to p-GaN. Effects of annealing temperature and acceptor concentration on ohmic characteristics were investigated. It was found that both ohmic contacts exhibited a contact resistivity of less than 4×10−3 Ωcm2 after 600 °C annealing. Moreover, fairly good ohmic behaviors were observed for Pd/Au even without annealing.
Healthcare is one of important factors for persons to keep their happiness during daily life. In order to maintaining good health conditions, daily continuous health monitoring is effective to find small symptoms before causing severe conditions. In this study, wearable, healthcare sensor sheets are proposed to monitor health conditions and activity, simultaneously, consisted of a skin temperature...
SiC devices are expected to operate at much higher temperature than Si devices. However, commercially available SiC devices are limited to the temperature almost same as Si devices. In order to operate SiC devices at high temperature, it is necessary to improve package technology and to design SiC devices properly for high temperature. In this study, robustness against thermal runaway of SiC-SBD is...
We have analyzed Hall effect in a thin-film transistor by actual experiments and device simulation. Particularly in this presentation, we show the sensitivity dependence on the applied voltage. These behaviors can be explained by the electric field in the channel layer for the operation regions. Additionally, the carrier mobilities and densities calculated using transistor equation and Hall effect...
Sensitivity of piezoelectric ultrasonic microsensors was investigated with sol-gel derived piezoelectric lead-zirconate-titanate (PZT) films under various pyrolysis temperatures. The sensors were fabricated on thin diaphragm structures, whose buckling deflection strongly affects the sensitivity and is controlled through stress of the PZT film. The pyrolysis temperature in the sol-gel process was varied...
This paper demonstrates successful fabrication of AlGaN/GaN high-electron-mobility transistors (HEMTs) with an AlGaN barrier layer directly regrown on a reactive-ion-etched GaN layer. The HEMT device fabricated on a high-mobility (>1000 cm2/Vs) GaN channel exhibited fairly excellent pinched-off characteristics with a maximum drain current of 90 mA/mm, whereas the device fabricated on a low-mobility...
This paper describes suppression of current collapse by field-plate (FP) in AlGaN/GaN MOS-HEMTs. Current collapse reduction was confirmed for a multi-gate fingered MOS-HEMT with a total gate width of 10 mm. Moreover, we have fabricated a 5-A class MOS-HEMT with both gate-FP and source-FP (dual-FP), showing more complete suppression in current collapse as compared to that with only gate-FP.
High Q and low TCF are elemental characteristics for SAW resonator, in order to realize high performance filters and duplexers for new LTE frequency bands. Authors have focused on the acoustic energy confinement in vicinity of substrate surface. A novel multi-layered structure substrate have realized incredibly high performances such as Q factor of 4000 and TCF of 8 ppm/°C compared with conventional...
Hall-effect measurements for n-type and p-type GaN with low doping concentration are presented. The GaN layers were grown by metal-organic vapor phase epitaxy on hydride-vapor-phase-epitaxy-grown free-standing GaN substrates. For n-GaN, the origin of acceptor which compensating donor is not only C but also native defects for the Si doping concentration of 1016 cm−3 level. The electron mobility is...
We have developed a planar device using In-Ga-Zn-O (IGZO) semiconductor for synapse element in neural network. First, we formed the planar device on a glass substrate. Next, we formed it on an LSI wafer. Both devices shows proper uniformities of film thicknesses and sufficient degradations of electric characteristics, which can be utilized for modified Hebbian learning proposed by us. These results...
We have developed a cross-point device using In-Ga-Zn-O (IGZO) semiconductor for synapse element in neural network. Horizontal 80 and vertical 80 metal lines make 6400 cross-point synapse integrated on a glass substrate. The electrical conductance gradually degrades by flowing current, which is available for modified Hebbian learning.
Wireless power transfer (WPT) is studied for battery charging in the IoT world. WPT via electric coupling is studied for apparatuses in water using the effect of large dielectric constant of water. One electrode is isolated from water and another electrode is exposed in water for underwater WPT. The power transfer efficiency is over 75%.
We demonstrated that heteroepitaxial ε-Ga2O3 thin films can be grown on (111) GGG substrates by mist CVD. The out-of-plane and in-plane epitaxial relationship between the ε-Ga2O3 thin film and the (111) GGG substrate was determined to be (0001) ε-Ga2O3 [10-10] // (111) GGG [-1-12] by XRD 2θ-ω and φ scanning. This is the first report on heteroepitaxial growth of ε-Ga2O3 thin films on (111) GGG substrates...
This paper describes the angular dependence of the nonparabolicity factor of the silicon band structure and the influence of the angular dependence on the density of states. In order to investigate the angular dependence of the nonparabolicity factor of the band structure, we calculate the silicon band structure using the first principle calculation. In order to investigate the influence of the angular...
The International Meeting for Future of Electron Devices, Kansai (IMFEDK) was established in 2003 to provide an international opportunity for technical discussion in Kansai, Japan. Multidisciplinary discussions by various researchers and engineers from different point of views are much expected in the meeting for creating embryos of science and/or technology to be the main stream of device technology...
We developed a microelectromechanical system to controllably fracture overhanging silicon micro-beams, in an attempt to fabricate conformal electrode pairs. Controlled fracture by applying tensile force in the <111> crystal direction produces flat, and very low roughness fracture surfaces, which are then utilized as conformal electrodes for inducing large area tunneling emission of electrons...
In this work, we report on high positive threshold voltage and respectable drain current density obtained from our AlGaN/GaN MIS-HEMTs with recessed-gate structure. After subjecting the device to reverse bias annealing, on top of improved subthreshold swing and leakage characteristics, its threshold voltage shifted from −0.2 V to +3.5 V. We have also confirmed that these desirable device characteristics...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.