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

Direct growth of GaN on misoriented 4H- and 6H-SiC (0001) Si-face substrates and electrical characteristics of n-GaN/p-SiC heterojunction mesa diodes are presented. GaN was grown by molecular-beam epitaxy (MBE) using elemental Ga and rf plasma-excited active nitrogen. SiC substrates misoriented 8° toward the [11-20] direction were used in this study. The surfaces of MBE-grown GaN layers have wavy features with peak-to-valley height of 30 nm. These features originated from the substrate misorientation. It was found that step bunching and large faceting along [01-10] and [10-10] directions occurred during the growth of GaN. Lowering the growth temperature suppresses large faceting, and results in reduction of the peak-to-valley height to 3 nm. However, the surface still has the same undulating features (on a smaller length scale). Mesa diodes were fabricated from the grown GaN layers. The correlation between the diode electrical characteristics and GaN growth conditions is discussed. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Direct growth of GaN on off-oriented SiC (0001) by molecular-beam epitaxy for GaN/SiC heterojunction bipolar transistor

The first-order Raman spectra of A 1 g and B 1 g mode in aragonite crystal were measured in the temperature range of 4.4∼630 K and the linewidths at these temperature were obtained. The temperature dependence of the linewidths was analyzed by the phonon dispersion curves based on the Born-von Karman model, and the results showed that it was caused approximately by the cubic anharmonic term in crystal potential energy.

Temperature Dependence of the Linewidth of the First-Order Raman Spectra for Aragonite Crystal

Growth evolution of cubic-GaN on sapphire (0 0 0 1) substrate by metalorganic molecular beam epitaxy

4H-SiC (0001) metal-oxide-semiconductor field-effect transistors (MOSFETs) with a 3-D gate structure, which has a top channel on the (0001) face and side-wall channels on the {112macr0} face, have been fabricated. The 3-D gate structures with a 1-5-mum width and a 0.8- mum height have been formed by reactive ion etching, and the gate oxide has been deposited by plasma-enhanced chemical vapor deposition and then annealed in N2O ambient at 1300degC. The fabricated MOSFETs have exhibited good characteristics: The I ON/I OFF ratio, the subthreshold swing, and V TH are 109, 210 mV/decade, and 3.5 V, respectively. The drain current normalized by the gate width is increasing with decreasing the gate width. The normalized drain current of a 1-mum-wide MOSFET is 16 times higher than that of a conventional planar MOSFET.

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Enhanced Drain Current of 4 H-SiC MOSFETs by Adopting a Three-Dimensional Gate Structure

What we believe to be a new mathematical procedure has been proposed for analyzing the rotational Maker-fringe data taking account of the effects of multiple reflections and interferences of the fundamental and second-harmonic beams in anisotropic plane-parallel plates. In the present formalisms partial overlaps of the fundamental and second-harmonic beams are fully included. A comparison between numerical simulations based on the proposed formalisms and experimental data obtained for a high-quality (0001) plane-parallel plate of 6H-SiC revealed the validity of our theory. We have determined the magnitudes of the nonlinear optical coefficients of 6H-SiC as d31=d32=6.7±0.8 pm/V, d15=d24=6.4±1.1 pm/V, and d33=−9.7±8.0 pm/V.

Jun Suda

Papers

Direct growth of GaN on off-oriented SiC (0001) by molecular-beam epitaxy for GaN/SiC heterojunction bipolar transistor

Temperature Dependence of the Linewidth of the First-Order Raman Spectra for Aragonite Crystal

Growth evolution of cubic-GaN on sapphire (0 0 0 1) substrate by metalorganic molecular beam epitaxy

Enhanced Drain Current of 4 H-SiC MOSFETs by Adopting a Three-Dimensional Gate Structure

Comprehensive analysis of multiple-reflection effects on rotational Maker-fringe experiments