Reverse Conducting Double Gate Lateral Insulated Gate Bipolar Transistor in SOI Based Technology

In this paper we report a lateral insulated gate bipolar device with an embedded anti-parallel diode (body diode) for use in half bridge or full bridge configurations. The device offers ultra-fast switching speed and low on-state resistance and is based on an SOI proprietary process earlier reported by us (F. Udrea, et. al., 2004). The device features double CMOS gates operated from an integrated CMOS controller. When the anode gate is biased negatively with respect to the anode a hole inversion layer is formed at the surface of the n-well which leads to enhanced injection of holes and therefore a lower on-state resistance. When the device is turned-off by inactivating both the cathode and anode gates the 'extra' inversion layer emitter is physically suppressed and the device turns-off fast. The device is experimentally demonstrated with full set of measured characteristics and compared on the same wafer with a classical LIGBT, an anode-shorted LIGBT and an LDMOSFET. It is shown that the Double Gate Enhanced Injection device offers a remarkably better switching/on-state/breakdown trade-off and, very importantly in some applications, it benefits from a fast, low on-state, embedded anti-parallel diode.