A CMOS compatible lateral emitter switched thyristor with enhanced turn-on capability

A new Lateral Emitter Switched Thyristor structure (LEST) is proposed and experimentally verified. The structure differs from the conventional LEST in that it embeds a floating ohmic contact between the n/sup -/ drift region and the n/sup +/ floating emitter. Both simulation and experimental results show that the device has an enhanced turn-on capability compared with the conventional LEST without deteriorating its other characteristics. The device is fabricated using a 3 μm CMOS process to have a 320 V breakdown voltage and a 0.7 V threshold voltage. Thyristor turn-on is observed at an anode voltage below 2 V. The maximum MOS controllable current density is in excess of 200 A/cm
²
with 5 V gate voltage.