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

In this paper, nitrided insulators such as N2O-grown oxides, deposited SiO2 annealed in N2O, and deposited SiNx/SiO2 annealed in N2O on thin-thermal oxides have been investigated for realization of high performance n- and p-type 4H-SiC MIS devices. The MIS capacitors were utilized to evaluate MIS interface characteristics and the insulator reliability. The channel mobility was determined by using the characteristics of planar MISFETs. Although the N2O-grown oxides are superior to the dry O2-grown oxides, the deposited SiO2 and the deposited SiNx/SiO2 exhibited lower interface state density (n-MIS: below 7x1011 cm-2eV-1 at EC-0.2 eV, p-MIS: below 6x1011 cm-2eV-1 at EV+0.2 eV) and higher channel mobility (n-MIS: over 25 cm2/Vs, p-MIS: over 10 cm2/Vs). In terms of reliability, the deposited SiO2 annealed in N2O exhibits a high charge-to-breakdown over 50 C/cm2 at room temperature and 15 C/cm2 at 200°C. The nitrided-gate insulators formed by deposition method have superior characteristics than the thermal oxides grown in N2O.

Electrical Characterization and Reliability of Nitrided-Gate Insulators for N- and P-Type 4H-SiC MIS Devices

Investigation of anharmonicity in rotational phonon mode for BaWO4 crystal

Temperature dependence of electrical properties in NiO thin films for ReRAM applications has been investigated. I-V measurements have been carried out in the temperature range from 100K to 523K. The resistance in the high resistance state (HRS) is almost independent of temperature below 250K, whereas it decreases with an activation energy of 300 meV above 250K. Hopping conduction and band conduction may be dominant in the low- and high-temperature range, respectively. Admittance spectroscopy on the NiO/n+-Si structureiireveals the existence of a high density of traps, which may contribute to the conduction in HRS. In the low resistance state (LRS), however, the resistance slightly increased in the whole temperature range and the trend is similar to that of metallic Ni film, indicating the metallic Ni defects is related to the conduction in LRS. The Pt/NiO/Pt structure demonstrated stable resistance switching even at temperature as high as 250°C or higher. Since other competitive nonvolatile memories will face severe difficulty in high-temperature operation, the present ReRAM shows promise for high-temperature application.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S1946427400030190

Temperature Dependence of Electrical Properties of NiO Thin Films for Resistive Random Access Memory

Second-order nonlinear-optical coefficients of 4H and 6H-SiC have been measured with the wedge technique. Using high-quality (11-20) samples as well as performing rigorous measurements and analyses, the three independent components, d31 (= d32), d15 (= d24), and d33, have been accurately determined. We have found that the nonlinear-optical coefficients are nearly the same between the measured 4H and 6H-SiC samples within the experimental accuracy; d31 = 5.4 pm/V, d15 = 6.2 pm/V, and d33 = 9.7pm/V.

Accurate Measurements of Second-Order Nonlinear-Optical Coefficients of Silicon Carbide

A quick method is proposed for measurement of the carbon-related hole trap (H1: +0.87 eV) density in an n-type GaN homoepitaxial layer using dual-color-sub-bandgap-light-excited isothermal capacitance transient spectroscopy. Shorter wavelength (390 nm) light irradiation is employed to cause the hole traps to be in the hole-occupied state. Longer wavelength (660 nm) light irradiation is then used to emit the hole from the trap to the valence band. The photoemission of holes is much quicker than the thermal emission, which reduces the measurement time. The trap density can be calculated from the capacitance transient.

https://iopscience.iop.org/article/10.35848/1347-4065/ab6863/pdf

Dual-color-sub-bandgap-light-excited isothermal capacitance transient spectroscopy for quick measurement of carbon-related hole trap density in n-type GaN

Jun Suda

Papers

Electrical Characterization and Reliability of Nitrided-Gate Insulators for N- and P-Type 4H-SiC MIS Devices

Investigation of anharmonicity in rotational phonon mode for BaWO4 crystal

Temperature Dependence of Electrical Properties of NiO Thin Films for Resistive Random Access Memory

Accurate Measurements of Second-Order Nonlinear-Optical Coefficients of Silicon Carbide

Dual-color-sub-bandgap-light-excited isothermal capacitance transient spectroscopy for quick measurement of carbon-related hole trap density in n-type GaN