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This paper is an important step toward the development of complex integrated circuit (IC) control electronics that have to attend to high-temperature environment power applications. We present in premiere a prototype set of essential mixed-signal ICs on SiC capable of controlling power switches and a lateral power MESFET able to operate at high temperatures, all embedded on the same chip. Also, we report for the first time the functionality of standard Si-CMOS topologies on SiC for the master–slave data flip-flop (FF) and data-reset FF digital building blocks designed with MESFETs. Concretely, we present the complete development of SiC-MESFET IC circuitry, able to integrate gate drivers for SiC power devices. This development is based on the mature and stable Tungsten–Schottky interface technology used for the fabrication of stable SiC Schottky diodes for the European Space Agency Mission BepiColombo. [ABSTRACT FROM PUBLISHER]

This paper presents the first integrated temperature sensor in a SiC power mosfet. An analytical model has been proposed to assess its behavior up to 300°C. We present the tested design and its advantages compared to other solutions. We also propose possible optimizations in order to simplify it and reduce its size. 2.25 mm2 power mosfets have been fabricated with and without temperature sensor. Measurements show that the temperature sensor does not impact the power mosfet characteristics and its integration does not demand supplementary process steps. To demonstrate the functionality of our integrated sensor, we have calibrated the temperature dependence of its resistance to assess the internal temperature of the device at different bias. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Currently, the demand by new application scenarios of increasing operating device temperatures in power systems is requiring new die-attach materials with higher melting points and suitable thermomechanical properties. This makes the die-attach material selection, die-attaching process, and thermomechanical evaluation a real challenge in nowadays power packaging technology. This paper presents a comparative analysis of the thermomechanical performance of high-temperature die-attach materials (sintered nano-Ag, AuGe, and PbSnAg) under harsh thermal cycling tests. This study is carried out using a test vehicle formed by four dice (considering Si and SiC semiconductors) and Cu substrates. Thermally cycled test vehicles have been thermomechanically evaluated using die-shear tests and acoustic microscopy inspections. Besides, special attention is paid to set up a nano-Ag sintering process, in which the effects of sintering pressure or substrate surface state (roughness and surface activation) on the die-attach layer are analyzed. As a main result, this study shows that the best die-attach adherence is obtained for nano-Ag when pressure is applied on the dice (using a specifically designed press) during the sintering process (11 MPa provided die-shear forces of 53 kgf). However, this die-attach presents a faster thermomechanical degradation under harsh thermal cycling tests than other considered high-temperature die-attach materials (AuGe and PbSnAg) and PbSnAg shows the best thermomechanical performances. [ABSTRACT FROM AUTHOR]

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The aim of this work is to present a characterization of a new silicon carbide (SiC) neutron detector fabricated at the Institute of Microelectronics of Barcelona (IMB-CNM-CSIC). The device is based on a 50 μ m thick p-n diode built in a 4H-SiC wafer. Performance studies were carried out under different neutron energy spectra, including thermal and quasi-monoenergetic fast neutrons at the CNA HiSPANoS facility. We implemented a method for the fabrication of enriched LiF conversion layers to use for the detection of thermal neutrons. The detector was proven to be capable of being used for thermal neutron detection with conversion layers of 10B and LiF. A detection efficiency of 6 ± 1% was achieved with a 25 μ m thick LiF conversion layer. It was also confirmed that the device can be employed for the detection of recoil nuclei and protons produced by fast neutrons. The spectra obtained experimentally were compared with PHITS simulations. This work represents the first step towards the design and fabrication of new SiC neutron detectors in the IMB-CNM-CSIC clean room with potential applications in various scientific and technological fields. [ABSTRACT FROM AUTHOR]

Abstract: In this work we will prove that SiC-based MIS capacitors can work in environments with extremely high concentrations of water vapor and still be sensitive to hydrogen, CO and hydrocarbons, making these devices suitable for monitoring the exhaust gases of hydrogen or hydrocarbons based fuel cells. Under the harshest conditions (45% of water vapor by volume ratio to nitrogen), Pt/TaO x /SiO2/SiC MIS capacitors are able to detect the presence of 1ppm of hydrogen, 2ppm of CO, 100ppm of ethane or 20ppm of ethene, concentrations that are far below the legal permissible exposure limits. [Copyright &y& Elsevier]

In this work, Silicon Carbide Schottky Barrier Diodes (SBDs) were inspected by Infrared Lock-In Thermography to study and determine the origin of structural weak spots resulting from their manufacturing and electro-thermal stressing tests. These spots are frequency modulated following three different approaches representative of the SBDs operating regimes and detected by their infrared emission, as they behave as hot spots. According to thermal results, such weak spots have originated from barrier modification due to the wire-bonding process, non-uniform active area resistance due to bad metallization electrical contact, deep level traps creation due to high energy implantation in the edge termination, and internal propagation of lattice defects during thermal cycling. [ABSTRACT FROM AUTHOR]