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A new vertical bipolar bidirectional switch (Bipac) with a buried layer is proposed for specific ac mains applications (230 V–50 Hz). It is mainly dedicated for the low load current ones (0.5 Arms) and must support a voltage of 750 V in the blocking state. Moreover, the Si-chip area must not exceed 10 mm2. The study of the new proposed Bipac structure is carried out using 2-D Sentaurus physical simulation. The operating principles are first validated, and then the physical and geometrical parameters of the buried layer are determined to meet the specifications. As compared to the classical Bipac, the Bipac with a buried layer exhibits a much higher current gain that makes it more attractive in replacing the triac in the targeted applications. [ABSTRACT FROM AUTHOR]

This article deals with the monolithic integration in silicon of a multiphase static power converter (dc/ac or ac/dc) for medium power applications, from few kilowatts to few tens of kilowatts with power devices’ blocking capability in the range of 600–1200 V. This article presents an original three-chip integration approach that combines both monolithic integration in silicon and printed circuit board (PCB) packaging process and takes advantage of both silicon-level technology and PCB-level technology within a limited and well-mastered complexity. The converter is integrated within only three new multiterminal power chips, which are then judiciously packaged on a PCB so as to minimize the switching cell stray inductance and the impact of voltage variations (dv/dt) across the common-mode stray capacitance of the assembly. The static and the dynamic operating modes of the proposed multiterminal power chips were validated using 2-D-Sentaurus TCAD simulations. The realized chips were packaged on a PCB to realize both classical and three-chip-based H-bridge inverters. First characterization results validate the electrical operating modes of the H-bridge inverter realized according to the three-chip approach. [ABSTRACT FROM AUTHOR]

This paper deals with the design of an ac switch structure for specific ac mains applications 230 V–50 Hz. The targeted power level is about a hundred watts, and the currently used converter circuits make use of bidirectional switches that are realized using anti-series connected MOS transistors. Despite the improvements in performance provided by some of these structures, their fabrication cost is still high and limits their widespread diffusion in a market shared with the triac. To replace the triac, an original current and voltage bidirectional bipolar device called a Bipolar ac (Bipac) is proposed, designed, realized, and characterized. It can be controlled both to turn-on and turn-off with respect to a single reference electrode. It exhibits a very low ON-state voltage drop that makes it interesting for specific mains applications with low load current (0.5 $\text{A}_{{\text {rms}}}$). The study of the Bipac structure is carried out using 2-D Sentaurus physical simulations. The Bipac structure is realized on n-type and on p-type substrates for two different wafer thicknesses. The operating modes of the monolithic bidirectional Bipac switch were validated through electrical characterizations. [ABSTRACT FROM AUTHOR]

This paper deals with the monolithic integration of a multiphase generic static power converter (dc/ac or ac/dc). The integration aims at minimizing wire bonds in order to improve the electrical performance as well as the reliability of power converters. To that end, three multiterminal monolithic power Si chips are devised and extensively studied by 2-D simulations. The first power chip integrates the reverse-conducting IGBT devices that compose the high-side part of the converter circuit. This chip is called the common anode and is validated through experimental realizations. The second power chip integrates the reverse-conducting IGBT devices that compose the low-side part of the converter. This chip is called the common cathode chip. The common anode and cathode power chips are judiciously packaged on a Printed Circuit Board substrate over which an insulating Kapton film is laid and through which window openings are realized. The partial flip-chip packaging, of the two power chips, enables the realization of a compact power H-bridge converter with the lowest stray inductance. The third chip integrates the power converter within a single silicon chip and, consequently, eliminates wire bonds. It is considered as the ultimate integration approach. The latter is validated on a monolithic H-bridge inverter by using Sentaurus mixed-mode 2-D numerical simulations. [ABSTRACT FROM AUTHOR]

Power device reliability is a multidisciplinary domain. It requires design and integration of sensors, implementation of signal processing algorithms that allow processing the different data provided by the different sensors in order to predict by statistical means the device failure occurrence and consequently anticipate the power device replacement. Currently, for device ageing studies in a laboratory, electrical measurements of device parameters are often used as an indicator of device ageing. Furthermore, smart metal‐oxide semi‐conductor technology integrates more and more sensors that permit to measure quantities such as on‐state resistance or junction temperature of the device. In power vertical diffused metal oxide semiconductor (VDMOS) assemblies, it would be interesting to make use of the VDMOS electrical parameters deviations in order to monitor the ageing state of the power assembly. To that end, we carry‐out in this paper a study mainly based upon electro‐thermo‐mechanical simulations in order to identify the power VDMOS electrical parameters that could be monitored in order to access to the mechanical state of the power assembly and therefore anticipate the assembly failure. The power VDMOS Ron as well as zero temperature coefficient (ZTC) point are of interest because they are sensitive to mechanical stress. Consequently, in this paper, a procedure to minimise temperature impact on the Ron of the VDMOS transistor such that one could use the Ron as mechanical state indicator is shown. Another solution that makes use of a specific operating point of VDMOS (ZTC) which is temperature independent is also studied by simulations and experiment. [ABSTRACT FROM AUTHOR]

In high current, high voltage, high temperature (T>125^\circC) power applications, commercially available conventional silicon thyristors are not suited because they present high leakage current. In this context, this paper presents a high-symmetrical (voltage) thyristor structure that presents a lower leakage current and higher breakover voltage as compared with the conventional thyristor at T>125^\circC. It is shown through 2-D physical simulations that the replacement of the P-emitter of a standard symmetrical thyristor by a judicious association of P diffusions and Schottky contacts at the anode side contributes to the reduction of the leakage current in the forward blocking state at high temperature. A fine tune of the anode side configuration will improve the forward OFF-state behavior with only a negligible ON-state voltage drop degradation. Moreover, the comparison with the conventional anode short thyristor shows that the insertion of Schottky contacts leads to the same improvements in terms of OFF-state forward breakover voltage and leakage current and also presents a high reverse blocking voltage. [ABSTRACT FROM PUBLISHER]