Nonuniform and latchup current detection in lateral conductivity modulated FETs

Three-dimensional effects on current distribution in lateral conductivity modulated power transistors such as the lateral insulated-gate bipolar transistor (LIGBT) are studied using the infrared microscopy technique. Nonuniform current distribution and the location of the latchup sites in these devices have been identified. This provides experimental insights into the design and optimization of these high-voltage power transistors. For optimized p/sup +/ anode LIGBT devices with a breakdown voltage of 600 V, a current density of 200 A/cm/sup 2/ at a forward voltage of 2 V, which is comparable to the DMOS IGBT, and a latchup current density above 800 A/cm/sup 2/ have been obtained.<
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