Development of SiC power module for high-speed switching operation

Abstract

In this work, SiC power module with sandwich structure is fabricated for high-speed switching operation at high temperature. A module structure of SiC power devices are sandwiched between two silicon nitride-active metal brazed copper circuit boards. To make a precise position and height control of the chip bonding, the top side (gate/source or anode pad side) of SiC power devices are flip-chip bonded to circuit electrodes using sub-micron Au particle with low temperature (250°C) and pressure-less sintering. The accuracy of the bonding position of chips was less than 10 μm and the accuracy of the height after bonding chips was less than 15 μm. The flip-chip bonding of SiC-JFET is successfully realized on the substrate without short or open failure electrically. Finally we joint the backside of the SiC-JFET (drain side) and the SiC-SBD (cathode side) to each circuit electrodes at once by means of reflow process with Au-12%Ge solder. Since the sandwitch module showed no fatigue afetr 500 times thermal cycle test between -40°C and 250°C and showed properly operation. The circuit operation of the module is confirmed by a double pulse-switching test.

A high-speed low side GaN e-HEMT driver with gate ringing and overshoot suppression

“…Therefore, a specific driver is needed to provide large driving current. However, providing large driving current in a short time means high di/dt, thus causing gate ringing and overshoot due to the parasitic inductance [17,18,19,20]. Exceeding the gate operating voltage range can affect the stability of the device or even damage it [14], and excessive ringing can also cause GaN devices to switch on and off by mistake (due to the low threshold voltage of GaN e-HEMT devices, usually ∼1.5 V) [21,22,23,24,25].…”

High-speed switching operation for a SiC CMOS and power module

“…For high-frequency operation, it is important to reduce the switching time of main circuits. To realize high-speed switching of the main circuit, the gate capacitor of power devices should be quickly charged and discharged [12]; in other words, a high-outputcurrent gate buffer is required and then the inductance between the gate buffer and power metal-oxide semiconductor field-effect-transistor (MOSFET) should be low [13], and the inductance of the main circuit should be reduced to suppress current and voltage surges [14,15,16]. In this study, the main circuit inductance was reduced and a SiC complementary metal-oxide semiconductor (CMOS), which can be operated at high temperatures [17], and power SiC MOSFET were installed in the same module to shorten the gate wire.…”

“…Our study explores the further faster switching of main circuits by using a power module for high-speed drive and SiC CMOS gate buffer with large output current characteristics of several amperes during the Miller plateau. Modules for the high-speed switching of the SiC power MOSFET in the main circuit has been studied recently [14,15,16]. In previous studies [15,16], a Si gate driver was placed outside the module and then the inductance of the main circuit in the module was reduced to realize the highspeed switching.…”

Fast Switching Planar Power Module With SiC MOSFETs and Ultra-low Parasitic Inductance

“…Efforts have been put into development of fast switching speed in power electronics [1]- [3]. Among others, this may be done by adding different components to the circuit, proposing turn-on/off strategies [4], [5], suggesting gate-driver circuits [6], [7], or by using new device-and package-structures [8], [9].…”