A5049607962- Radio Frequency Integrated Circuit Design
- GaN-based semiconductor devices and materials
- Advanced Power Amplifier Design
- Semiconductor Quantum Structures and Devices
- Electron and X-Ray Spectroscopy Techniques
- Ion-surface interactions and analysis
- X-ray Spectroscopy and Fluorescence Analysis
- Atrial Fibrillation Management and Outcomes
- Cardiac Arrhythmias and Treatments
- Advancements in Semiconductor Devices and Circuit Design
- Microwave Engineering and Waveguides
- Silicon Carbide Semiconductor Technologies
- Semiconductor materials and devices
- Acute Myeloid Leukemia Research
- Dermatology and Skin Diseases
- Endometrial and Cervical Cancer Treatments
- Cancer Diagnosis and Treatment
- Cancer Research and Treatments
- Petri Nets in System Modeling
- Exercise and Physiological Responses
- melanin and skin pigmentation
- Dermatologic Treatments and Research
- Alcohol Consumption and Health Effects
- Semiconductor Lasers and Optical Devices
- Ga2O3 and related materials
Kumamoto University
2024
Matsumoto University
2024
NEC (Japan)
1994-2012
Fujita Health University
2001-2011
Tokai University
2005
Yokogawa Electric (Japan)
1989
Osaka University
1964-1988
Abstract Background Quality‐switched (QS) lasers are well‐known effective treatment for removing solar lentigines. However, the high incidence of post‐inflammatory hyperpigmentation (PIH) raises concern in darker skin types. This is first study comparing efficacies and incidences PIH Asian with different degrees irradiation between two QS lasers. Method In total, 355 lentigines 193 cases, types III–V, were randomly divided into four groups. All cases received single laser treatment. Clinical...
A novel GaAs power FET with a field-modulating plate (FP-FET) and operated at drain bias voltage of 24 V was developed. Regarding the performance an FP-FET under wideband code division multiple access (WCDMA) operation, its peak output significantly degraded in saturated-output-power region when FP length short. However, by introducing sufficiently large length, it demonstrated that peak-power degradation can be suppressed. In particular, amplifier fabricated 1.5 /spl mu/m exhibited no WCDMA...
A single-chip GaN-FET amplifier exhibits record output powers of C-band solid-state amplifiers under continuous-wave (CW) and pulsed operation conditions. At 5.0 GHz, the developed with 24 mm gate periphery delivered a CW 100 W power 12.9 dB linear gain 31% power-added efficiency 155 13.0 gain.
This paper describes a high-efficiency, high-output-power GaN power amplifier for S-band radar applications. The uses an inverse class-F configuration high efficiency. matching circuit includes 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nd</sup> harmonic resonant to compensate FET parasitics. developed single-chip delivers output of 95 W with added efficiency (PAE) 72% and linear gain 19.8 dB at 2.6 GHz. To the best our knowledge, this is...
We have successfully developed a novel AlGaN/GaN FET with dual field-modulating-plates (FPs). The breakdown voltage is enhanced from 125 to 250 V by adding the second FP conventional structure. Benefiting first FP, no current collapse observed simultaneously. Since effectively reduces feedback capacitance, this device provides 3-dB higher gain along increased linearity and stability. Under 2.15-GHz W-CDMA modulation scheme, dual-FP-FET 24-mm gate periphery achieved state-of-the-art...
Microwave power performance of double-doped AlGaAs-InGaAs-AlGaAs heterojunction field-effect transistors (HJFET's) operated at a drain bias 3 V is described. The fabricated 1.0 μm gate-length HJFET exhibited maximum current 500 mA/mm, transconductance 300 mS/mm, and gate-to-drain breakdown voltage 10 V. Power for 14 mm gate periphery device demonstrated output 1.7 W with 66% power-added efficiency (PAE) 900 MHz. When the was tuned PAE, it delivered 71% PAE an 1.2 W. results indicate that...
This paper describes the first demonstration of a 76 GHz gallium nitride (GaN) power amplifier (PA) on silicon substrate. The PA microwave monolithic IC (MMIC) was fabricated by using AlGaN/GaN FET with maximum oscillation frequency 160 and breakdown voltage over 50 V. For reducing transmission loss, we used CPW line substrate low loss 0.5 dB/mm at GHz. precise design PA, large signal model developed. developed 3-stage exhibited an output 12 dBm 5 dB gain 75-81
Enhancement-mode buried gate InGaP/AlGaAs/InGaAs heterojunction FETs (HJFETs) were successfully fabricated by using a highly-selective wet recess etching technique. The HJFET exhibited maximum drain current of 202 mA/mm, peak transconductance 330 mS/mm and gate-drain breakdown voltage 33 V. Standard deviation the threshold was 60 mV, which is less than one fifth that conventional AlGaAs/InGaAs HJFET. No appreciable frequency dispersion in measured, indicating developed with structure...
A single-ended amplifier using a single-die GaN-FET was successfully developed for W-CDMA cellular base-station systems. The delivers peak saturated output power of 280 W with linear gain 12.6 dB at drain voltage 48 V under 2.15 GHz 3GPP signal input. It is believed that the record in sigle-ended amplifiers 2 band. high efficiency 29% also obtained 8 back off from power.
Two-dimensional self-consistent full band Monte Carlo (FBMC) simulator was developed for electron transport in wurtzite phase AlGaN/GaN heterojunction (HJ) FET. Recessed gate Al/sub 0.2/Ga/sub 0.8/N/GaN HJFET structures with an undoped cap layer were simulated, where the spontaneous and piezoelectric polarization effects taken into account. The effect shown to not only increase current density, but also improve carrier confinement, hence transconductance. An off-state drain breakdown voltage...
A single-ended amplifier using small packaged GaN-FETs exhibits a record 2.14 GHz W-CDMA output power. The amplifier, composed of paralleled 48 mm gate periphery FET die, delivers peak saturated power 371 W with linear gain 11.2 dB at drain voltage 45 V under 3GPP signal input. density (output power/package size) 1.1 W/mm2 is twice as high that the existing over 300 GaAs-FET amplifiers. low 5 MHz offset ACLR −36 dBc efficiency 24% also obtained 8 back off from
A pulsed 0.75 kW output GaN-FET amplifier for L/S band high power applications has been successfully developed. single-ended configuration is adopted to make the compact and simple. The delivers a saturated of under RF operation at 2.14 GHz, which believed be highest reported in an single-packaged device.
A C-band high power amplifier was successfully developed with a single-chip GaN-based FET. At 4.0GHz, the fabricated 24-mm wide FET delivers 62 W and 156W under CW pulsed operating conditions, respectively universal test fixture. The internal matching circuit designed to be set up in half-size package as compared that for GaAs-based comparable-power-level amplifiers. GaN-FET gate periphery 61W output 10.2dB linear gain 42% power-added efficiency conditions. To best of our knowledge, this is...
This paper describes a successfully developed high-power and high-efficiency C-band GaAs FET amplifier for satellite communication systems. To realize high efficiency in amplifier, an HFET well-designed applications is developed, precise design carried out. The employed achieves reduction gate leakage current while maintaining maximum drain current. For of large-signal model parameters are extracted using pulsed I-V S-parameter measurements. Based on this model, second harmonic impedances as...
This paper describes a successfully developed L-band depletion-mode GaAs-based heterostructure FET (HFET) with field-modulating plate (FP) for cellular base station applications. The FP-HFET power amplifier, consisting of four 86.4 mm gate-width chips, delivered 53.6 dBm (230 W) output at 2.1 GHz 11 dB linear gain and 42% PAE operated drain bias 22 V. A low adjacent channel leakage ratio (ACPR) -35 dBc 25% was obtained an 46 dBm, indicating superior linearity characteristics under elevated...
Fexofenadine, a histamine H 1 -receptor antagonist, is approved for the treatment of pruritus associated with atopic dermatitis. The effects fexofenadine on scratching behaviour, and plasma levels eotaxin were assessed in new model Mice fed diet low Mg 2+ Zn (special S) compared mice normal (N) or S plus HCl weeks 0-10 (S + F ), 0-5 ) 6-10 (seven per group). Compared group N, showed significantly greater frequency, concentrations; these three variables lower than S. Scratching frequency...
This paper describes an AlGaN/GaN FET power amplifier module delivering a continuous wave (CW) output of more than 20 W at 26 GHz. To achieve high breakdown characteristics with reduced current collapse and gain, we have developed 0.2 µm-long recessed-gate field-modulating plate (FP), achieving operation voltage 25 V even quasi-millimeter frequencies. A single-ended FP-FET for quasi- millimeter frequency has been fabricated the first time. The using 6.3-mm-wide single chip exhibited 20.7 W,...
This paper reports an L-band power AlGaAs/GaAs heterostructure FET with a field-modulating plate (FP-HFET), which accomplished 100 W output high density of 1.16 W/mm at drain bias voltage 30 V. The developed FP-HFET is promising for achieving improved performance and reduced size digital cellular base station systems.
This paper describes a 28-GHz power amplifier with 4.5-W output under CW operation. The utilizes four fully matched MMICs, in which 0.35-/spl mu/m-long gate GaAs-based heterojunction FETs are employed. developed also provides continuous-wave (CW) of 3 W over the bandwidth 2 GHz at Ka-band.
A C-band high-power amplifier with two GaN-based FET chips exhibits record output powers under continuous-wave (CW) and pulsed operation conditions. At 5.0 GHz, the developed GaN-FET delivers a CW 208 W power 11.9 dB linear gain 34% power-added efficiency. It also shows 232 8.3 gain.