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In this paper, the use of 3.3 kV SiC MOSFETs, Fast Si IGBTs and the mix of both in the so called Cross-Hybrid Switch (XS) and Bimode Cross-Hybrid Switch (BXS) are considered for their application on Galvanically Insulated Modular Converters (GIMC) cells. The semiconductors typically operate under Soft Switching conditions to allow high frequency operation resulting in size and weight minimization while keeping a high efficiency. The high frequency (10 kHz) and Soft Switching operation in the selected semiconductors have been first evaluated by applying 2D semiconductor device simulations. The simulation results allow to identify the impact of device parameters such as the Si IGBTs Lifetime adjustment and the Si IGBT – SiC MOSFET chip surface ratio on the BXS devices, over the on-state and switching losses. Accordingly, different 3.3kV dual HiPak testing samples have been implemented and experimentally evaluated on a 200 kW DC/DC GIMC cell test bench. The comparison between the 3.3 kV Fast Si IGBTs, SiC MOSFETs and BXS shows clear functional benefits of using MV SiC MOSFETs in resonant mode operation, allowing an increase of the GIMC cell power capability by 30 - 35 % for the same module current rating compared to the use of Fast IGBTs. In a similar way, the BXS devices can provide and intermediate power capability increase of around 20-25%, minimizing the installed Si and SiC chip area that can be used as an enabler for improvement of the GIMC technology impacting the cost and performance of the semiconductor devices applied on the GIMC cells

In this paper we present a new radial design concept for an optimized layout of anode shorts in the Bi-mode Insulating Gate Transistor (BiGT). The study shows that the arrangement of the n+-stripes plays a key role for the on-state characteristics of the BiGT. With the aid of 3D device simulations the visualization of the plasma distribution during the on-state conduction was obtained in a 0.25 × 4 mm2 large BiGT model area. The influence of the dimensioning and layout of the anode shorts was simulated and compared with measured on-state curves. A clear improvement of plasma distribution in the device when the stripes are arranged orthogonally (radially) to the pilot-IGBT boundary is observed in 3D simulations. Measurements confirm lower on-state losses as a result of better utilization of the device area.

As the importance of yield analysis in microsystems is increasing, designers can no longer neglect it in the design phase. The lack of reliable statistical methods to analyze yield of a design in a quick and efficient way has been a persistent problem until recently. One successful approach, worst-case based yield analysis, has not been completely exploited in the conventional design process of microsystems, making yield optimization of novel microsystem designs difficult. This paper proposes the integration of worst-case based yield analysis methods with one of the most conventional tools of microsystem design - FEM based design. By generating nonlinear response surface models from FEM simulations, efficient advanced worst-case based yield analysis methods can be utilized. We demonstrate the yield enhancement of FEM based microsystems with two different examples, a U-shaped thermal actuator and a capacitive pressure sensor.

We present a simulation study on power device structures based on a dualization of the thyristor equivalent circuit. This dualization results in new power devices, namely, "circuit breaker" and "safe controlled power switch". Both the circuit breaker and the safe controlled power switch can be used to protect against over currents. The circuit breaker exhibits self protection against over currents while the safe controlled power switch with inherent over current turn-off capability is controlled by the MOS gates of the device. These novel power devices have very good on-state characteristics that are comparable to the on-state characteristics of the injection enhancement IGBTs.

We describe the operation and application of a new class of power devices which have regenerative turn-off capability. The presented regenerative turn-off devices are (1) circuit breaker (2) safe controlled power switch and (3) regenerative diode. Regenerative turn-off devices are conceptually "dual" to regenerative turn-on devices like the Shockley diodes or thyristor type devices. Regenerative turn-off devices are normally ON and enable current flow until a certain current/voltage level above which the regenerative turn-off action starts. Therefore, they can be developed as circuit breakers, safe controlled power switches and regenerative diodes. Regenerative diodes are "normally open" and block at small reverse current/voltage levels (Vemulapati, 2007). Regenerative turn-off devices can be realized from a series connection of normally ON type JFETs which are connected as controlled source ballasts. Full gate controlled device (safe controlled power switch) can be obtained with the addition of MOS gates to the circuit breaker. High injection (thyristor) versions of the circuit breaker and safe controlled power switch can be developed and they exhibit good plasma concentration which is comparable to that of the advanced IGBTs (Rosensaft, 2007). Regenerative diode can also be developed from the basic structure of a Dual Thyristor which has a low or neglectable threshold voltage and closes at reverse polarity. Regenerative diode is superior compared to Schottky diodes and junction barrier controlled Schottky (JBS) rectifier both in forward and reverse directions (Vemulapati, 2007), but of course, requires a more complicated technology. JBS rectifiers are obtained with a good compromise between p-n and Schottky diodes (Baliga, 1998). Though regenerative diode has inferior on-state behavior when compared to that of the synchronous rectifier, it does not require any external triggering.