Normally off Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> /GaN MOSFETs are fabricated by utilizing a simple tetramethylammonium hydroxide (TMAH) treatment as postgate-recess process. The TMAH-treated device with gate length of 2.5 μm exhibited excellent performances, such threshold voltage 3.5 V, maximum drain current 336 mA/mm, and breakdown 725 along extremely small leakage...

A normally off GaN MOSFET was proposed by utilizing an extremely high 2-D electron-gas density (> 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">14</sup> / cm xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) at AlGaN/GaN heterostructure as source and drain, which can be obtained controlling the tensile stress accompanied with growth of on silicon substrate. The fabricated Al <sub xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O...

Two types of fin-shaped field-effect transistors (FinFETs), one with AlGaN/GaN heterojunction and the other heavily doped heterojunction-free GaN layer operating in junctionless mode, have been fabricated characterized. The threshold voltages both devices shift toward positive direction from large negative value as fin width decreases. Both exhibit high ON-state performance. FinFETs show superior OFF-state performance because current flows through volume channel layer, which can be fully...

AlGaN/GaN-based fin-shaped field-effect transistors with very steep side-wall have been fabricated by utilizing electron-beam lithography and subsequent anisotropic wet etch in tetramethyl ammonium hydroxide solution. The investigate device demonstrated extremely broad transconductance (g <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> ) ranging from ~0 to ~8 V at xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> = 10 V, which is...

Heavily doped GaN nanochannel fin-shaped field-effect transistors (FinFETs) without heterojunction have been fabricated and characterized for the first time. Simplified pragmatical technology epitaxial growth FinFET process was used to achieve nanodevices with a channel width from 40 100 nm gate length of 1 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu\hbox{m}$</tex></formula> . They exhibit...

We have demonstrated the lateral multifinger-type Schottky barrier diode (SBD) with bonding pad over active structure fabricated on AlGaN/GaN heterostructure prepared sapphire substrate. The GaN-SBD size of 9 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${\rm mm}^{2}$</tex></formula> exhibited excellent device characteristics such as forward current 4.5 A at 1.5 V, leakage 6...

An AlGaN/GaN-based Ω-shaped nanowire fin-shaped FET (FinFET) with a fin width of 50 nm was fabricated using tetramethylammonium hydroxide (TMAH)-based lateral wet etching. atomic layer deposited (ALD) HfO2 side-wall served as the etching mask. ALD Al2O3 and TiN layers were used gate dielectric metal, respectively. The structure fully depletes active body almost completely separates depleted from underlying thick GaN buffer layer, resulting in superior device performance. top-down processing...

DC and 1/f noise performances of the AlGaN/GaN fin-shaped field-effect transistor (FinFET) with fin width 50 nm were analyzed. The FinFET exhibited approximately six times larger normalized drain current transconductance, compared to those planar metal-insulator-semiconductor heterostructure field-effect-transistor (MISHFET) fabricated on same wafer. It was also observed that improved performance lower magnitude 8.5×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...

The low-frequency noise (LFN) characteristics of AlGaN/GaN FinFETs with omega-gate and combined two-dimensional electron gas (2DEG) MOS conduction are investigated. It is found that LFN dominated by carrier number fluctuations whatever the width fin. Charge trapping in narrow devices one order magnitude lower than wide fin device. In devices, sidewall prevails mainly stems from Al2O3 gate dielectric. Instead, top HEMT structure dominates mostly governed GaN layer close to 2DEG channel.

Lateral GaN nanowire gate-all-around transistor has been fabricated with top-down process and characterized. A triangle-shaped 56 nm width was implemented on the GaN-on-insulator (GaNOI) wafer by utilizing (i) buried oxide as sacrificial layer (ii) anisotropic lateral wet etching of in tetramethylammonium hydroxide solution. During subsequent AlGaN epitaxy source/drain planar regions, no growth occurred nanowire, due to self-limiting property. Transmission electron microscopy...

We investigated the performances of GaN junctionless fin-shaped field-effect transistors (FinFETs) with two different types gate structures; overlapped- and partially covered-gate. DC, low-frequency noise (LFN), pulsed I-V characterization measurements were performed analyzed together in order to identify conduction mechanism examine both interface buffer traps devices. The fabricated device overlapped-gate structure exhibits improved DC performance compared covered-gate, even though its...

A crack-free GaN film grown on 4-inch Si (111) substrate is proposed using two-step growth methods simply controlled by both III/V ratio and pressure. Two-step process found to be effective in compensating the strong tensile stress layer substrate. The high-resolution X-ray diffraction (XRD) rocking curves of (002) (102) planes for epitaxial with method are 317 432 arcsec, while corresponding values reference sample without 550 1207 respectively. reduced threading dislocation obtained ~2 ×...

AlGaN/GaN Fin-shaped field-effect transistors (FinFETs) with nano-sized Fin width ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{W}_{\mathrm {Fin}}$ </tex-math></inline-formula> ) from 20 nm to 230 are characterized using low-frequency noise (LFN) measurement. All devices exhibit 1/ notation="LaTeX">$f$ shape Hooge mobility fluctuations (HMF) at subthreshold region and carrier number (CNF)...

Two different lateral GaN-based nanowire gate-all-around transistors with and without 2-D electron gas (2-DEG) channel were fabricated using top-down approach, their noise characteristics investigated. The transistor 2-DEG had a relatively larger cross section, which consists of regrown AlGaN/GaN plateau on the trapezoidal GaN layer, exhibited negative threshold voltages (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> ). consisted...

The recessed-gate AlGaN/GaN metal–oxide–semiconductor heterostructure field-effect transistors (MOSHFETs) with a p-GaN back-barrier studied in this work exhibited much lower buffer leakage current than those without the back-barrier. threshold voltage of device was controlled by varying depth gate recess etching, and value as high 2.9 V obtained deep gate-recess etching into channel layer. structure has advantage both low voltage, which is important for power-switching applications. In...

This paper presents a new concept, supported by 3-D TCAD simulations, for improving the performance and subthreshold swing (SS) of enhancement-mode AlGaN/GaN fin-shaped field-effect transistors (FinFETs). By choosing appropriate device parameters, formation 2-D electron gas (2DEG) can be delayed such as to ensure simultaneous activation 2DEG sidewall MOS channels at positive threshold voltage normally off operation. The channel starts forming in middle fin, whereas edges are depleted lateral...

Charge trapping in gallium-nitride (GaN) metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) is a serious reliability challenge but still poorly understood. A promising opportunity to investigate physical defect properties has become available through nanoscale GaN fin-MIS-HEMTs which are small enough be sensitive the impact of individual defects. In this work, we extract four pre-existing single defects, identified by their correlated random telegraph noise (RTN)...