A Novel Low on-State Voltage SOI LIGBT With Enhanced Conductivity Modulation

A novel composite device structure with enhanced conductivity modulation silicon on insulator (SOI) lateral insulated gate bipolar transistor (LIGBT) which consists of a normal LIGBT (NLT) region, an nMOS region (NM) and a pMOS region (PM) is proposed in this article. By employing a parasitic n-p-n bipolar transistor, the thyristor in the NLT performs a high electron current in ON-state. As a result, the conductivity modulation in the NLT region is dramatically enhanced, which leads to the improvement of the current capability and the forward ON-state voltage drop. In addition, due to the parasitic diode in the substrate of NM, the potential of p-base of the NLT can be clamped at the ON-state voltage drop of the diode, which guarantees the current saturated capability of the LIGBT.