Single-crystal gallium oxide (Ga2O3) metal-oxide-semiconductor field-effect transistors were fabricated on a semi-insulating β-Ga2O3 (010) substrate. A Sn-doped n-Ga2O3 channel layer was grown by molecular-beam epitaxy. Si-ion implantation doping performed to source and drain electrode regions for obtaining low-resistance ohmic contacts. An Al2O3 gate dielectric film formed atomic deposition passivated the device surface significantly reduced leakage. The with length of 2 μm showed effective...

Depletion-mode field-plated Ga <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> metal-oxide-semiconductor field-effect transistors were demonstrated for the first time. Substantial enhancement in breakdown voltage was achieved with a gate-connected field plate. The device channels, formed by selective-area Si ion implantation doping of an undoped epilayer, electrically isolated highly...

This paper reviews the progress of N-polar () GaN high frequency electronics that aims at addressing device scaling challenges faced by electron mobility transistors (HEMTs) for radio-frequency and mixed-signal applications. Device quality (Al, In, Ga)N materials heterostructures are developed using molecular beam epitaxy metalorganic chemical vapor deposition. The principles polarization engineering designing HEMT structures will be outlined. performance, behavior microwave power devices as...

The band alignment of Al2O3/n-Ga2O3 was investigated by x-ray photoelectron spectroscopy (XPS). With a gap 6.8 ± 0.2 eV measured for Al2O3, the conduction and valence offsets at interface were estimated to be 1.5 0.7 eV, respectively. offset also obtained from tunneling current in (2¯01) metal-oxide-semiconductor (MOS) diodes using Fowler-Nordheim model. electrically extracted value good agreement with XPS data. Furthermore, MOS exhibited small capacitance-voltage hysteresis loops,...

Deep acceptor doping of β-Ga2O3 with Mg and N was demonstrated by implantation the impurity ions into n-type bulk substrates. Systematic physical electrical characterizations were performed to demonstrate recovery implantation-damaged crystals activation dopant atoms thermal annealing at 1000–1200 °C in an N2 atmosphere. found exhibit much lower diffusivity than Mg, thus enabling use higher temperatures maximize efficiency without significantly altering profile. Consequently,...

A guard ring (GR) was employed to improve the breakdown voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">br</sub> ) of vertical Ga xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Schottky barrier diodes (SBDs) with or without a field-plate (FP) by eliminating electric field concentration at edges anode and FP electrodes. The GR structure formed nitrogen (N)-ion implantation. Four...

The process of charge injection plays an important role in organic semiconductor devices. We review various experimental techniques that allow to be separated from other competing processes, and quantify the efficiency a contact. discuss dependence on parameters such as energy barrier at interface, carrier mobility semiconductor, its density (doping level), presence mobile ions, sample geometry. Based these findings, we outline guidelines for forming ohmic contacts present examples contact...

We describe the development of N-polar GaN-based high electron mobility transistors grown by N2 plasma-assisted molecular beam epitaxy on C-face SiC substrates. High AlGaN∕GaN modulation-doped two-dimensional gas channels were grown, and with excellent dc small-signal performance fabricated these wafers. Large-signal dispersion was observed, trap states responsible for this identified, layer designs to remove dispersive effects traps demonstrated. Finally, an AlGaN-cap used reduce gate...

Enhancement-mode β-Ga2O3 metal–oxide–semiconductor field-effect transistors with low series resistance were achieved by Si-ion implantation doping of the source/drain contacts and access regions. An unintentionally doped Ga2O3 channel background carrier concentration that was fully depleted at a gate bias 0 V gave rise to positive threshold voltage without additional constraints on dimensions or device architecture. Transistors length 4 µm delivered maximum drain current density (IDS) 1.4...

A current aperture vertical electron transistor (CAVET) with a Mg-ion-implanted blocking layer (CBL) and channel regrown by plasma assisted molecular beam epitaxy (MBE), is successfully demonstrated on bulk GaN to work as high voltage device. The fabrication of the device combined drift region grown metalorganic chemical vapor deposition (MOCVD), hold voltage, AlGaN/GaN layers plasma-MBE conduct current. registered maximum 4 kA· cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Depletion-mode vertical Ga <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> metal-oxide-semiconductor field-effect transistors featuring a current aperture were developed on halide vapor phase epitaxial drift layer grown bulk β-Ga (001) substrate. Three ion implantation steps employed to fabricate the n <sup xmlns:xlink="http://www.w3.org/1999/xlink">++</sup> source regions, lateral...

Gallium nitride (GaN) is becoming the material of choice for power electronics to enable roadmap increasing density by simultaneously enabling high-power conversion efficiency and reduced form factor. This because low switching losses GaN high-frequency operation which reduces bulky passive components with negligible change in efficiency. Commercialization GaN-on-Si materials has led entry devices into medium-power market since performance-over-cost even first-generation products looks very...

Abstract The electron mobility in depletion-mode lateral β-Ga 2 O 3 (010) metal–oxide–semiconductor field-effect transistors (MOSFETs) with an n-channel formed by Si-ion (Si + ) implantation doping was extracted using low-field electrical measurements on FET structures. An undoped Ga buffer layer protected the channel against charge compensation suppressing outdiffusion of deep Fe acceptors from semi-insulating substrate. molecular beam epitaxy growth temperature identified as a key process...

The effects of ionizing radiation on β-Ga2O3 metal-oxide-semiconductor field-effect transistors (MOSFETs) were investigated. A gamma-ray tolerance as high 1.6 MGy(SiO2) was demonstrated for the bulk Ga2O3 channel by virtue weak MOSFETs' output current and threshold voltage. MOSFETs remained functional with insignificant hysteresis in their transfer characteristics after exposure to maximum cumulative dose. Despite intrinsic hardness Ga2O3, radiation-induced gate leakage drain dispersion...

A vertical β-Ga2O3 metal–oxide–semiconductor field-effect transistor featuring a planar-gate architecture is presented. The device was fabricated by an all-ion-implanted process without requiring trench etching or epitaxial regrowth. Mg-ion-implanted current blocking layer (CBL) provided electrical isolation between the source and drain except at aperture opening through which conducted. Successful action realized gating Si-ion-implanted channel above CBL. Thermal diffusion of Mg induced...

Enhancement-mode (E-mode) vertical β-Ga <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> metal-oxide-semiconductor (MOS) field-effect transistors featuring a current aperture were developed on single-crystal (001) substrate. Nitrogen ions implanted into drift layer grown by halide vapor phase epitaxy to form blocking layers (CBLs) for source-drain isolation, while Si degenerately doped...

The channel temperature (Tch) and thermal resistance (Rth) of Ga2O3 metal-oxide-semiconductor field-effect transistors were investigated through electrical measurements complemented by electrothermal device simulations that incorporated experimental parameters. analysis technique was based on a comparison between DC pulsed drain currents (IDS) at known applied biases, where negligible self-heating under conditions enabled approximation Tch to the ambient (Tamb) hence correlation IDS Tch....

Atomic scale details of the formation point defects and their evolution to phase transformation in silicon (Si) implanted β-Ga2O3 were studied using high resolution scanning transmission electron microscopy (STEM). The effect Si implantation was as a function dose atoms, detailed mechanism lattice recovery observed both situ ex annealing β-Ga2O3. created nanoscale dark spots STEM images, which we identified local γ-Ga2O3 inclusions generated by relaxation due ⟨010⟩ screw dislocations...

The thermal behavior of Fe as a compensating acceptor impurity in β-Ga2O3 (010) was studied view growing interests semi-insulating Fe-doped Ga2O3 substrates for the realization high-performance field-effect transistors (FETs). An anomalous redistribution beyond extent intrinsic diffusion revealed by secondary ion mass spectroscopy device-relevant structures where grown homoepitaxially on doped Si (Si+) implantation and annealed at high temperatures. enhanced attributed to an athermal process...

Early stage degradation of AlGaN/GaN high electron mobility transistors (HEMTs) with different threading dislocation densities (TDDs) submitted to off-state voltage bias stress was studied. It found that, for the conditions used, HEMTs TDD ∼1010 cm−2 show pronounced in terms maximum drain current, gate-lag, and trap generation measured by current trapping characteristics, a slight gate leakage observed also ∼108 cm−2, no significant devices ∼107 range. The results illustrate importance...

Comparison between pulsed and CW large signal RF performance of field-plated <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> -Ga <sub xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> MOSFETs has been reported. Reduced self-heating when pulse resulted in a power added efficiency 12%, drain 22.4%, output density 0.13...

β-Ga <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> is an attractive material for highvoltage applications and has the potential monolithically integrated RF devices. A combination of Raman nanoparticle thermometry measurement thermal simulation been used to measure peak channel temperature due self-heating in MOSFETs. The resistance measured at gate surface device center was 88 mm ·...

We evaluated the band offsets at SiO2/β-Ga2O3 (010) interface by X-ray photoelectron spectroscopy (XPS). Plasma chemical vapor deposition with a liquid tetraethyl orthosilicate source for SiO2 was used to prepare an SiO2(40 nm)/Ga2O3 sample and SiO2(3 XPS analyses. The bandgap of determined be 8.7 ± 0.2 eV. A large conduction offset 3.1 eV corresponding valence 1.0 were SiO2/Ga2O3 interface. These results suggest that gate insulator is favorable Ga2O3 field effect transistors operating under...