The present invention relates to a power semiconductor device such as a diode and thyristor. In a semiconductor device such as a diode and thyristor having at least one pn junction between a pair of main surfaces, a first main electrode is formed on the surface of one of the main surfaces and a second main electrode is formed on the surface of the other one of the main surfaces. A semiconductor lattice defect is formed such that its lattice defect density increases gradually in the direction from the first main electrode to the second main electrode. Since the distribution of carrier density in the conduction state can be flattened according to the invention, the reverse recovery charge can be reduced substantially without causing the ON-state voltage to increase.

Power semiconductor device

Double pulse test (DPT) is a widely accepted method to evaluate the switching characteristics of semiconductor switches, including SiC devices However, the observed switching performance of SiC devices in a PWM inverter for induction motor drives is almost always worse than the DPT characterization, with slower switching speed, more switching losses, and more serious parasitic ringing This paper systematically investigates the factors that limit the SiC switching performance from both the motor side and inverter side, including the load characteristics of induction motor and power cable, two more phase legs for the three-phase PWM inverter in comparison with the DPT, and the parasitic capacitive coupling effect between power devices and heat sink Based on a three-phase PWM inverter with 1200 V SiC MOSFETs, test results show that the induction motor, especially with a relatively long power cable, will significantly impact the switching performance, leading to a switching time increase by a factor of 2, switching loss increase up to 30% in comparison with that yielded from DPT, and serious parasitic ringing with 15 μs duration, which is more than 50 times of the corresponding switching time In addition, the interactions among the three phase legs cannot be ignored unless the decoupling capacitors are mounted close to each phase leg to support the dc bus voltage during switching transients Also, the coupling capacitance due to the heat sink equivalently increases the junction capacitance of power devices; however, its influence on the switching behavior in the motor drives is small considering the relatively large capacitance of the motor load

Evaluation of Switching Performance of SiC Devices in PWM Inverter-Fed Induction Motor Drives

This paper presents the design process of a 312-kVA three-phase silicon carbide inverter using ten parallel-connected metal–oxide–semiconductor field-effect-transistor power modules in each phase leg. The design processes of the gate-drive circuits with short-circuit protection and power circuit layout are also presented. Measurements in order to evaluate the performance of the gate-drive circuits have been performed using a double-pulse setup. Moreover, electrical and thermal measurements in order to evaluate the transient performance and steady-state operation of the parallel-connected power modules are shown. Experimental results showing proper steady-state operation of the power converter are also presented. Taking into account measured data, an efficiency of approximately 99.3% at the rated power has been measured for the inverter.

High-Efficiency 312-kVA Three-Phase Inverter Using Parallel Connection of Silicon Carbide MOSFET Power Modules

The purpose of the present invention is to reduce the wiring inductance of a power semiconductor module. It comprises a first power semiconductor device, a second power semiconductor device, a first conductor unit which is opposed to the first power semi conductor device, a second conductor unit which is opposed to the first conductor unit across the first power semiconductor device, a third conductor unit which is opposed to the second power semiconductor device, a fourth conductor unit which is opposed to the third conductor unit across the second power semiconductor device, a first intermediate conductor unit which extends from the first conductor unit, a second intermediate conductor unit which extends from the fourth conductor unit and, a positive electrode side first terminal, and a positive electrode side second terminal which project from the first intermediate conductor unit, and a negative electrode side first terminal and a negative electrode side second terminal which project from the second intermediate conductor unit. The negative electrode side first terminal is arranged in a position adjacent to the positive electrode side first terminal. The negative electrode side second terminal is arranged in a position adjacent to the positive electrode side second terminal.

Power semiconductor module

SiC power semiconductors are believed to offer an attractive solution for motor drive application in electrified vehicles in 5∼10 years. Newer generations of commercial SiC MOSFETs in the 900∼1200V class are significantly improved in energy losses, reliability and price. To analyze the potential impact of SiC technology for HEV inverter systems, performance gain of SiC MOSFETs over existing silicon IGBTs must be quantified, which translates to vehicle-level fuel economy and value for consumers. This study will look into HEV drive-cycle simulation results based on inverters of silicon and SiC switching devices, and evaluate the performance improvement and cost premiums for the newer semiconductor technology. Reliability and qualification criteria of SiC MOSFETs for automotive application will also be discussed.

Performance and cost considerations for SiC-based HEV traction inverter systems

There is provided a power module semiconductor device allowing reduction in size and weight of a thin type SiC power module. The power module semiconductor device (1) includes: a ceramic substrate (10); a first pattern (D (K4)) of a first copper plate layer (10 a) disposed on a surface of the ceramic substrate; a first semiconductor chip (Q4) disposed on the first pattern; a first pillar connection electrode (18 o) disposed on the first pattern; and an output terminal (O) connected to the first pillar connection electrode.

Power module semiconductor device

SiC Power devices are expected to greatly improve the efficiencies and operating capabilities of next generation electric and hybrid electric vehicles. The use of these devices allows for drastic size and weight reduction at the module and system levels of motor drives used in automotive applications. A new SiC MOSFET structure with both gate and source trenches is presented. This greatly reduces device on-resistance while preventing oxide destruction at the gate trench bottoms. Finally new packaging methods under development are outlined that take advantage of the benefits these new devices have to offer by transfer molding them in a high temperature resistant epoxy resin. This leads to modules with low thermal resistance and high power density that, when configured as a three phase inverter, reduce total system footprint and parasitic inductance.

Development of SiC power devices and modules for automotive motor drive use

The power module semiconductor device ( 2 ) includes: an insulating substrate ( 10 ); a first pattern ( 10 a ) (D) disposed on the insulating substrate ( 10 ); a semiconductor chip (Q) disposed on the first pattern; a power terminal (ST, DT) and a signal terminal (CS, G, SS) electrically connected to the semiconductor chip; and a resin layer ( 12 ) configured to cover the semiconductor chip and the insulating substrate. The signal terminal is disposed so as to be extended in a vertical direction with respect to a main surface of the insulating substrate.

Power module semiconductor device and inverter equipment, and fabrication method of the power module semiconductor device, and metallic mold

The power module semiconductor device (2) includes: an insulating substrate (10); a first pattern (10a) (D) disposed on the insulating substrate (10); a semiconductor chip (Q) disposed on the first pattern; a power terminal (ST, DT) and a signal terminal (CS, G, SS) electrically connected to the semiconductor chip; and a resin layer (12) configured to cover the semiconductor chip and the insulating substrate. The signal terminal is disposed so as to be extended in a vertical direction with respect to a main surface of the insulating substrate. There is provided a power module semiconductor device having a vertical terminal transfermold in which structure thereof is simple and the number of parts is reduced, thereby achieving space saving.

Toshio Hanada

Papers

Power module semiconductor device

Development of SiC power devices and modules for automotive motor drive use

Power module semiconductor device and inverter equipment, and fabrication method of the power module semiconductor device, and metallic mold

Power module semiconductor device and inverter device, power module semiconductor device producing method, and mold

SiC Trench Devices with Ultra Low Ron