Gallium nitride (GaN) and its allied binaries InN and AIN as well as their ternary compounds have gained an unprecedented attention due to their wide-ranging applications encompassing green, blue, violet, and ultraviolet (UV) emitters and detectors (in photon ranges inaccessible by other semiconductors) and high-power amplifiers. However, even the best of the three binaries, GaN, contains many structural and point defects caused to a large extent by lattice and stacking mismatch with substrates. These defects notably affect the electrical and optical properties of the host material and can seriously degrade the performance and reliability of devices made based on these nitride semiconductors. Even though GaN broke the long-standing paradigm that high density of dislocations precludes acceptable device performance, point defects have taken the center stage as they exacerbate efforts to increase the efficiency of emitters, increase laser operation lifetime, and lead to anomalies in electronic devices. The p...

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Luminescence properties of defects in GaN

Wide bandgap semiconductors show superior material properties enabling potential power device operation at higher temperatures, voltages, and switching speeds than current Si technology. As a result, a new generation of power devices is being developed for power converter applications in which traditional Si power devices show limited operation. The use of these new power semiconductor devices will allow both an important improvement in the performance of existing power converters and the development of new power converters, accounting for an increase in the efficiency of the electric energy transformations and a more rational use of the electric energy. At present, SiC and GaN are the more promising semiconductor materials for these new power devices as a consequence of their outstanding properties, commercial availability of starting material, and maturity of their technological processes. This paper presents a review of recent progresses in the development of SiC- and GaN-based power semiconductor devices together with an overall view of the state of the art of this new device generation.

A Survey of Wide Bandgap Power Semiconductor Devices

An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Semiconductor device, and manufacturing method thereof

and Perspectives Sophie Carenco,†,‡,§,∥,⊥ David Portehault,*,†,‡,§ Ced́ric Boissier̀e,†,‡,§ Nicolas Meźailles, and Cleḿent Sanchez*,†,‡,§ †Chimie de la Matier̀e Condenseé de Paris, UPMC Univ Paris 06, UMR 7574, Colleg̀e de France, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France ‡Chimie de la Matier̀e Condenseé de Paris, CNRS, UMR 77574, Colleg̀e de France, 11 Place Marcellin Berthelot, 75231 Paris Cedex 05, France Chimie de la Matier̀e Condenseé de Paris, Colleg̀e de France, 11 Place Marcellin Berthelot, 75231 Paris Cedex 05, France Laboratory Heteroelements and Coordination, Chemistry Department, Ecole Polytechnique, CNRS-UMR 7653, Palaiseau, France

Nanoscaled metal borides and phosphides: recent developments and perspectives

Silicon carbide (SiC) power devices have been investigated extensively in the past two decades, and there are many devices commercially available now. Owing to the intrinsic material advantages of SiC over silicon (Si), SiC power devices can operate at higher voltage, higher switching frequency, and higher temperature. This paper reviews the technology progress of SiC power devices and their emerging applications. The design challenges and future trends are summarized at the end of the paper.

https://ieeexplore.ieee.org/ielaam/41/8031005/7815312-aam.pdf

Review of Silicon Carbide Power Devices and Their Applications

The impact of the III/V ratio during growth on the polytype and crystalline quality of nonpolar AlN grown on 4H-SiC (110) was investigated. Growth of AlN was carried out by molecular-beam epitaxy (MBE) using elemental Al and rf-plasma excited nitrogen. Polytype replication from the SiC substrate to the grown AlN epilayer occurred under Al-rich conditions, i.e., 4H-AlN (110) was grown on 4H-SiC. On the other hand, the thermally stable 2H-AlN (110) polytype was grown under N-rich conditions. The best crystalline quality of AlN was obtained for slightly Al-rich conditions. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Impact of III/V ratio on polytype and crystalline quality of AlN grown on 4H-SiC (110) substrate by molecular-beam epitaxy

Surface recombination velocity on mesa sidewalls of SiC p-n diodes with various surface passivation conditions was evaluated from the device-size-dependent preexponential factor of recombination current ( ${J}_{\text {0rec}}$ ) The diodes passivated by SiO2 with postoxidation nitridation were dipped into HF to eliminate a shunt current, which is evoked by the nitrided SiO2 layer and disturbs the analysis of the recombination current For accurate determination of the surface recombination velocity, an effective recombination zone width was precisely derived taking account of the distribution of carrier density in the depletion layer The surface recombination velocity of the diodes without any passivation and with the postoxidation nitridation (NO annealing at 1250 °C for 70 min) was determined as $\text {12}\times \text {10}^{\text {7}}$ and $\text {60}\times \text {10}^{\text {5}}$ cm/s, respectively, which indicates that the postoxidation nitridation can reduce the surface recombination by a factor of about 20 We confirmed that TCAD simulation could reproduce the current–voltage characteristics by utilizing the extracted parameters In addition, an evaluation method was proposed to determine the surface recombination velocity from the high-current region, where diffusion current is dominant

Determination of Surface Recombination Velocity From Current–Voltage Characteristics in SiC p-n Diodes

Effects of the sequential implantation of Mg and N ions into GaN for p-type doping

High-resolution X-ray diffraction measurements of GaN and AlGaN grown on 4H- and 6H-SiC(0001) vicinal substrates with misorientation angles of up to 9° are presented. Growth of (Al)GaN was carried out by plasma-assisted molecular beam epitaxy. The c-axis tilt, i.e., inclination of the (Al)GaN c-axis relative to that of SiC, was systematically investigated. The inclination angle clearly depended on the SiC substrate misorientation angle, while it was independent of the (Al)GaN growth temperature, SiC polytype, and substrate misorientation direction. The behavior observed for both GaN and AlGaN is in excellent agreement with the model proposed previously by Nagai for the InGaAs/GaAs system.

https://iopscience.iop.org/article/10.1143/JJAP.48.020202/pdf

Jun Suda

Papers

Impact of III/V ratio on polytype and crystalline quality of AlN grown on 4H-SiC (110) substrate by molecular-beam epitaxy

Determination of Surface Recombination Velocity From Current–Voltage Characteristics in SiC p-n Diodes

Effects of the sequential implantation of Mg and N ions into GaN for p-type doping

Systematic Investigation of c-Axis Tilt in GaN and AlGaN Grown on Vicinal SiC(0001) Substrates

Characterization of ZrB2(0001) surface prepared by ex situ HF solution treatment toward applications as a substrate for GaN growth