LATERAL IGBT IN THIN SOI FOR HIGH-VOLTAGE, HIGH-SPEED POWER IC

A high voltage LIGBT built in ultra-thin silicon-on-insulator (SOI) wi th a linearly graded doping profile is reported. The highest breakdown voltage of 720 V was measured in an LIGBT built in 0.5 pm SOI with a 4 mu m buried oxide. A forward voltage drop of 6 V at 100 Acm(-2) and a turn-off time of 140 ns have been achieved in the same device. Devic e forward voltage drop is very sensitive to the SOI thickness due to t he recombination of carriers at the two silicon-silicon dioxide interf aces. An SOI thickness of 0.5 mu m and an n-buffer doped to 10(18) cm( -3) have been found to be a reasonable trade-off between the breakdown voltage and the forward voltage drop.