Low-Loss SOI-LIGBT With Dual Deep-Oxide Trenches

摘要

A 500-V silicon-on-insulator lateral insulated gate bipolar transistor (SOI-LIGBT) is proposed and investigated for the first time. The device features dual deep-oxide trenches (DDOTs) formed in the drift region. TheDDOT assists in sustaining the electric potential from the collector, which enables the SOI-LIGBT to reduce its drift region length. At the same breakdown voltage of 560 V, the drift region length is reduced from 47 μm for the conventional SOI-LIGBT to 23.4 μm for the proposed SOI-LIGBT. Due to the small-sized drift region, decreased amount of stored carrier and fast depletion of the drift region during the turn-off process are realized. The experiments demonstrate that the proposed SOI-LIGBT exhibits a superior tradeoff between turn-off loss ( EOFF) and on-state voltage drop ( VON) to the conventional SOI-LIGBT. EOFF of the proposed DDOT SOI-LIGBT is 36.9% lower than that of the conventional SOI-LIGBT at the same VON of 1.61 V. The DDOT can be fabricated simultaneouslywith the formation of the isolation trenches in a developed SOI bipolar–CMOS–DMOS–IGBT process.