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Functional Green Nanomaterials Designing Approach to Spectroscopic Evaluation
Published in Kaushik Pal, Nanomaterials for Spectroscopic Applications, 2021
Ahmed Emad, Irene S. Fahim, Tawfik Ismaila
Modifications are investigated in order to surpass Shockley-Queisser limit. These modifications either in fabrication or structure would maintain high efficiency [11]. The effectiveness of widebandgap materials in solar cells will reflect in enhancement for efficiency [12]. Wideband gap-based semiconductors owe an energy bandgap of more than 2.2 eV [12]. Gallium nitride (GaN) and silicon carbide (SiC) are examples of wide bandgap semiconductors of the third generation. The promising characteristics for wide bandgap materials are their highly shifted breakdown point of the electric field. WBG semiconductors are fabricated under high temperature. This is considered an advantage since these materials can resist for a long time under high temperature exposed to the cell [13, 14]. The strategy for WBG usage is decreasing the leakage current in the cell. Since the difference between the lower energy level in the conduction band and higher level in the valence band is higher than 2 eV, this would make the intrinsic carriers’ concentration lower than usual. This is the principle for the positive effect caused by WBG materials.
SiC MOS Devices
Published in Krzysztof Iniewski, Tomasz Brozek, Krzysztof Iniewski, Micro- and Nanoelectronics, 2017
Wide-bandgap semiconductors offer substantial benefits for electronic devices operating at extreme conditions such as high temperature, high power, and high speed. Silicon carbide (SiC) is attractive because of its high critical breakdown field, high thermal conductivity, and high electron saturation velocity. In addition to these important material characteristics, the high-quality thermal oxide on SiC enables metal–oxide–semiconductor field-effect transistors (MOSFETs) for power applications. Of the many different crystal structures (polytypes) of SiC having different stacking sequences of Si–C bilayers, the 4H- and 6H-SiC polytypes are the most common for electronics applications. Their properties are compared with those of Si in Table 3.1. 4H-SiC is preferred for power electronics because of its larger band-gap and higher bulk electron mobility. Although SiC diodes for power applications have been commercially available for more than 10 years, the first generation of SiC power MOSFET circuits has only been commercially available since 2011. While the cost of the SiC chip is higher than that of the Si power chip, both the overall system cost and size are reduced using SiC, since less cooling is required. This smaller size and weight are especially important for automotive and avionics applications. With the availability of 6 in. diameter 4H-SiC substrates allowing for SiC circuit fabrication in Si fabrication facilities, rapid scale-up of SiC power electronics is expected over the next few years.
2 Zeroth-Level Packaging Materials
Published in Mitel G. Pecht, Rakesh Agarwal, Patrick McCluskey, Terrance Dishongh, Sirus Javadpour, Rahul Mahajan, Electronic Packaging: Materials and Their Properties, 2017
Mitel G. Pecht, Rakesh Agarwal, Patrick McCluskey, Terrance Dishongh, Sirus Javadpour, Rahul Mahajan
Wide-bandgap semiconductors such as SiC, III-V nitrides, and related semiconductors are currently attracting increasing attention due to their interesting physical properties, different from conventional semiconductors (like Si and GaAs). Rapid improvement of the material quality and of the knowledge of physical properties is now generating development in high-power, high-temperature, high-frequency electronics and blue light emitters. III-Nitride-based semiconductor compounds, including binary InN, GaN, A1N, ternary InxGa1-xN, AlxGa1-xN and quaternary InGaAIN, are the most promising material systems for future visible, ultraviolet photodetectors, light-emitting diodes (LEDs), and high-temperature electronics. Currently, available Si and SiC solid-state UV photodetectors suffer from weaknesses such as low quantum efficiency (indirect bandgap), poor solar blindness and fragility in harsh environments.
Direct bonding of Ni nanoparticles to a semiconductor Al electrode in air and its form
Published in Welding International, 2023
Yasunori Tanaka, Keiko Koshiba, Tomonori Iizuka, Mayumi Ito, Koichi Higashimine, Kohei Tatsumi
Recently, wide bandgap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN), which have superior physical properties to silicon (Si), have attracted attention. Power devices using these semiconductors can operate at high temperatures of 200 °C or higher [1–3]. However, it is difficult to ensure bond reliability at temperatures above 200 °C with current solder bonding technology, and a new high heat-resistant mounting technology is needed [4,5]. Sintering bonding using metal nanoparticles has been attracting attention as an alternative to solder bonding for high heat resistance, and Ag nanoparticles and Cu nanoparticles have been evaluated for bonding [6–9]. Bonding using metal nanoparticles is expected to be a high heat-resistant bonding technology because the size effect of the nanoparticles enables bonding at a temperature lower than the melting point of the bulk metal, and after bonding, the temperature becomes the melting point of the bulk metal.
Theoretical analysis of betavoltaic cells based on pDSBD structure
Published in Radiation Effects and Defects in Solids, 2023
Shanxue Xi, Chunzhi Zhou, Yiyun Zhang, Haijun Li, Zungang Wang, Zhiqiang Liu, Xiaoyan Yi, Jinmin Li
Since the concept of betavoltaic-effect cell was discovered in 1953 (5), there have been many reports on betavoltaic cells (6–11). Most of the energy conversion materials reported in the early stage are silicon. The main disadvantages of silicon-based converters are low efficiency and semiconductor structure degradation caused by radiation damage (12,13). Theoretical studies show that the theoretical conversion efficiency of betavoltaic cells is positively correlated with the band gap () width of semiconductor materials (14). It is feasible to choose wide-bandgap semiconductors as energy conversion materials: higher theoretical energy conversion efficiency, stronger anti-radiation, and better performance at high temperatures (15–17).
The Analysis Model of AlGaN/GaN HEMTs with Electric Field Modulation Effect
Published in IETE Technical Review, 2020
Luoyun Yang, Baoxing Duan, Ziming Dong, Yandong Wang, Yintang Yang
Gallium nitride (GaN) is one of the third generation of wide-bandgap semiconductor materials without the inherent shortcomings of the first two generations of semiconductor materials, like Si and GaAs. Due to its wide band gap (> = 3.4 eV), high breakdown field (3MV/cm), high electron saturation speed (>2 × 107cm/s), high thermal conductivity and excellent properties, GaN material is suitable for high-power, high-temperature, and high-frequency applications [1]. GaN power devices [2] are considered to be the core of next-generation power devices, especially for the AlGaN/GaN heterojunction material system. High concentration (>1 × 1013cm−2) and mobility (1000–2000 cm2/V. s) 2DEG are generated at the interface of the heterojunction because the spontaneous polarization and piezoelectric polarization effects [3–5]. High electron mobility transistor (HEMT) has developed rapidly in recent years based on this heterojunction material system [6–9]. In high-power AlGaN/GaN HEMT devices, the breakdown voltage (BV) is a key parameter that we need to consider [10]. Researchers have designed many methods and techniques to get higher breakdown voltage and lower specific on-resistance, such as increase of breakdown voltage on AlGaN/GaN HEMTs by employing proton implantation [11], AlGaN/GaN HEMTs with integrated slant field plates [12], the new RESURF AlGaN/GaN HEMTs [13] and so on [14–16].