Electrical Characteristic Study of an SOI-LIGBT With Segmented Trenches in the Anode Region

This paper presents the electrical characteristic of a 500 V silicon-on-insulator (SOI) lateral insulated-gate bipolar transistor (LIGBT) with segmented trenches in the anode (STA) region. The STA-LIGBT features segmented n + anodes and segmented trenches. The segmented n + anodes are shorted to the p + anode, which accelerates the extraction of stored electrons during the device turn-OFF. The segmented trenches are arranged between the p + anode and the shorted n + anode. The resistors between the adjacent segmented trenches and the adjacent segmented n + anodes contribute to low snapback voltage ( $V_{S}$ ) while maintain high current density. In addition, an internal diode is formed by introducing the shorted n + anode. The 3-D simulations and the experiments are carried out to characterize the electrical performances of the STA-LIGBT and its internal diode. Compared with the conventional SOI-LIGBT, the STA device achieves a 73% improvement in turn-OFF time ( $t_{\mathrm{\scriptscriptstyle OFF}}$ ) at the same current density. Correspondingly, the internal diode of the STA-LIGBT achieves a forward voltage drop ( $V_{F}$ ) of 1.32 V and a reverse recovery time ( $t_{\mathrm {rr}}$ ) of 321 ns, which are superior to those of a conventional p-i-n SOI diode.