The Experts below are selected from a list of 5352 Experts worldwide ranked by ideXlab platform
Siddharth Rajan - One of the best experts on this subject based on the ideXlab platform.
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electrostatic engineering using extreme permittivity materials for ultra Wide Bandgap Semiconductor transistors
IEEE Transactions on Electron Devices, 2021Co-Authors: Nidhin Kurian Kalarickal, Zixuan Feng, A Anhar Uddin F M Bhuiyan, Zhanbo Xia, Wyatt Moore, Joe Mcglone, A R Arehart, S A Ringel, Hongping Zhao, Siddharth RajanAbstract:The performance of ultra-Wide Bandgap Semiconductors like ${\beta }$ -Ga2O3 is critically dependent on achieving high average electric fields within the active region of the device. In this article, we show that dielectrics like BaTiO3 with extremely high dielectric constant can provide an efficient field management strategy by improving the uniformity of electric field profile within the gate–drain region of lateral field-effect transistors. Using this strategy, we achieved high average breakdown field of 1.5 and 4 MV/cm at gate–drain spacing ( ${L}_{\text {gd}}$ ) of 6 and $0.5~{\mu }\text{m}$ , respectively in ${\beta }$ -Ga2O3, at a high channel sheet charge density of $1.6\,\,{\times }\,\,10^{{13}}$ cm−2. The high channel charge density along with the high breakdown field enabled a record power figure of merit ( ${V}_{\text {br}}^{{2}}/{R}_{\text {ON}}$ ) of 376 MW/cm2 at a gate–drain spacing of ${3}~{\mu }\text{m}$ .
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beta ga 2 o 3 delta doped field effect transistors with current gain cutoff frequency of 27 ghz
IEEE Electron Device Letters, 2019Co-Authors: Chandan Joishi, Nidhin Kurian Kalarickal, Joe Mcglone, A R Arehart, S A Ringel, Shahadat H Sohel, Mark Brenner, Saurabh Lodha, Wu Lu, Siddharth RajanAbstract:As an ultra-Wide Bandgap Semiconductor, $\beta $ -Ga2O3 has attracted great attention for high-power, high-voltage, and optoelectronic applications. However, until now, high-frequency performance of gallium oxide devices has been limited to relatively low current gain cutoff frequencies below 5 GHz. Here, we show that highly localized delta-doping designs can enable high-sheet-charge density to enable devices with short gate lengths that allow high-frequency operation. Field-effect transistors with a gate length of 120 nm on such delta-doped $\beta $ -Ga2O3 are reported here with extrinsic unity current gain frequency of 27 GHz. The device has a peak drain current of 260 mA/mm, transconductance (gm) of 44 mS/mm, and three-terminal off-state breakdown voltage of 150 V. These results demonstrate that the potential of $\beta $ -Ga2O3 for future RF and millimeter-wave device applications.
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prospects for the application of gan power devices in hybrid electric vehicle drive systems
Semiconductor Science and Technology, 2013Co-Authors: Ming Su, Chingchi Chen, Siddharth RajanAbstract:GaN, a Wide Bandgap Semiconductor successfully implemented in optical and high-speed electronic devices, has gained momentum in recent years for power electronics applications. Along with rapid progress in material and device processing technologies, high-voltage transistors over 600?V have been reported by a number of teams worldWide. These advances make GaN highly attractive for the growing market of electrified vehicles, which currently employ bipolar silicon devices in the 600?1200?V class for the traction inverter. However, to capture this billion-dollar power market, GaN has to compete with existing IGBT products and deliver higher performance at comparable or lower cost. This paper reviews key achievements made by the GaN Semiconductor industry, requirements of the automotive electric drive system and remaining challenges for GaN power devices to fit in the inverter application of hybrid vehicles.
Satoshi Ashihara - One of the best experts on this subject based on the ideXlab platform.
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antenna enhanced high harmonic generation in a Wide Bandgap Semiconductor zno
Epj Web of Conferences, 2019Co-Authors: Kotaro Imasaka, Tomohiro Kaji, Tsutomu Shimura, Satoshi AshiharaAbstract:We demonstrate high harmonic generation (HHG) into deep-UV range in a ZnO single crystal with resonant nanoantennas. Non-perturbative HHG is successfully induced by optical excitation of as low as 20 GW/cm2 . The spectral selection rule is found to reflect crystal symmetry, suggesting the possibility of nano-scaled EUV sources and band-structure reconstruction.
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antenna enhanced high harmonic generation in a Wide Bandgap Semiconductor zno
Optics Express, 2018Co-Authors: Kotaro Imasaka, Tomohiro Kaji, Tsutomu Shimura, Satoshi AshiharaAbstract:High harmonic generation (HHG) in solids has great potential for coherent extreme ultraviolet (EUV) sources, all-optical band-structure reconstruction, and electron dynamics metrology. Solid HHG driven by plasmonic near-fields will open a new paradigm, enabling high repetition-rate HHG with a compact laser, HHG manipulation with meta-surfaces, and precise control over carrier trajectory. In this paper, we demonstrate antenna-enhanced HHG in a Wide-Bandgap Semiconductor ZnO. By exploiting gold nano-antennas resonating at the driver wavelength of 2 μm, we successfully trigger HHG at input intensity of ~0.02 TW/cm2 and observe harmonic radiations up to 9th-order. Orders-of-magnitude enhanced conversion efficiency at the hot-spots brings about ten-fold enhancement in the total yield. The spectral selection rule is found to reflect crystal symmetry, suggesting the possibility of nano-scaled EUV sources and band-structure reconstruction.
Nidhin Kurian Kalarickal - One of the best experts on this subject based on the ideXlab platform.
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electrostatic engineering using extreme permittivity materials for ultra Wide Bandgap Semiconductor transistors
IEEE Transactions on Electron Devices, 2021Co-Authors: Nidhin Kurian Kalarickal, Zixuan Feng, A Anhar Uddin F M Bhuiyan, Zhanbo Xia, Wyatt Moore, Joe Mcglone, A R Arehart, S A Ringel, Hongping Zhao, Siddharth RajanAbstract:The performance of ultra-Wide Bandgap Semiconductors like ${\beta }$ -Ga2O3 is critically dependent on achieving high average electric fields within the active region of the device. In this article, we show that dielectrics like BaTiO3 with extremely high dielectric constant can provide an efficient field management strategy by improving the uniformity of electric field profile within the gate–drain region of lateral field-effect transistors. Using this strategy, we achieved high average breakdown field of 1.5 and 4 MV/cm at gate–drain spacing ( ${L}_{\text {gd}}$ ) of 6 and $0.5~{\mu }\text{m}$ , respectively in ${\beta }$ -Ga2O3, at a high channel sheet charge density of $1.6\,\,{\times }\,\,10^{{13}}$ cm−2. The high channel charge density along with the high breakdown field enabled a record power figure of merit ( ${V}_{\text {br}}^{{2}}/{R}_{\text {ON}}$ ) of 376 MW/cm2 at a gate–drain spacing of ${3}~{\mu }\text{m}$ .
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beta ga 2 o 3 delta doped field effect transistors with current gain cutoff frequency of 27 ghz
IEEE Electron Device Letters, 2019Co-Authors: Chandan Joishi, Nidhin Kurian Kalarickal, Joe Mcglone, A R Arehart, S A Ringel, Shahadat H Sohel, Mark Brenner, Saurabh Lodha, Wu Lu, Siddharth RajanAbstract:As an ultra-Wide Bandgap Semiconductor, $\beta $ -Ga2O3 has attracted great attention for high-power, high-voltage, and optoelectronic applications. However, until now, high-frequency performance of gallium oxide devices has been limited to relatively low current gain cutoff frequencies below 5 GHz. Here, we show that highly localized delta-doping designs can enable high-sheet-charge density to enable devices with short gate lengths that allow high-frequency operation. Field-effect transistors with a gate length of 120 nm on such delta-doped $\beta $ -Ga2O3 are reported here with extrinsic unity current gain frequency of 27 GHz. The device has a peak drain current of 260 mA/mm, transconductance (gm) of 44 mS/mm, and three-terminal off-state breakdown voltage of 150 V. These results demonstrate that the potential of $\beta $ -Ga2O3 for future RF and millimeter-wave device applications.
Abhiroop Chattopadhyay - One of the best experts on this subject based on the ideXlab platform.
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optimization of high voltage Wide Bandgap Semiconductor power diodes
IEEE Transactions on Electron Devices, 2015Co-Authors: K Shenai, Abhiroop ChattopadhyayAbstract:High-voltage (≥100 V) power diodes fabricated on Wide Bandgap Semiconductors such as silicon carbide (SiC) and gallium nitride are generally rated for punch-through leakage current and employ a buffer layer sandwiched between the drift region and substrate. A simple and accurate method for the extraction of important diode design parameters is presented and validated using extensive static current-voltage and capacitance-voltage measurements of high-voltage (≥600 V) commercial SiC junction-barrier-controlled Schottky diodes from room temperature to 250 °C. It is shown that there is significant potential for further optimization of the performance of SiC power diodes.
Kotaro Imasaka - One of the best experts on this subject based on the ideXlab platform.
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antenna enhanced high harmonic generation in a Wide Bandgap Semiconductor zno
Epj Web of Conferences, 2019Co-Authors: Kotaro Imasaka, Tomohiro Kaji, Tsutomu Shimura, Satoshi AshiharaAbstract:We demonstrate high harmonic generation (HHG) into deep-UV range in a ZnO single crystal with resonant nanoantennas. Non-perturbative HHG is successfully induced by optical excitation of as low as 20 GW/cm2 . The spectral selection rule is found to reflect crystal symmetry, suggesting the possibility of nano-scaled EUV sources and band-structure reconstruction.
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antenna enhanced high harmonic generation in a Wide Bandgap Semiconductor zno
Optics Express, 2018Co-Authors: Kotaro Imasaka, Tomohiro Kaji, Tsutomu Shimura, Satoshi AshiharaAbstract:High harmonic generation (HHG) in solids has great potential for coherent extreme ultraviolet (EUV) sources, all-optical band-structure reconstruction, and electron dynamics metrology. Solid HHG driven by plasmonic near-fields will open a new paradigm, enabling high repetition-rate HHG with a compact laser, HHG manipulation with meta-surfaces, and precise control over carrier trajectory. In this paper, we demonstrate antenna-enhanced HHG in a Wide-Bandgap Semiconductor ZnO. By exploiting gold nano-antennas resonating at the driver wavelength of 2 μm, we successfully trigger HHG at input intensity of ~0.02 TW/cm2 and observe harmonic radiations up to 9th-order. Orders-of-magnitude enhanced conversion efficiency at the hot-spots brings about ten-fold enhancement in the total yield. The spectral selection rule is found to reflect crystal symmetry, suggesting the possibility of nano-scaled EUV sources and band-structure reconstruction.
