A Novel Approach to Suppress the Collector-Induced Barrier Lowering Effect in Narrow Mesa IGBTs

A recessed p⁺-cathode IGBT (RP-IGBT) structure with very narrow mesa is analyzed through 3-D simulations in 1.2-kV field stop technology. Compared with a conventional narrow mesa IGBTs, the RP-IGBT can effectively restrain the collector-induced barrier lowering effect and hence, two-thirds reduction in saturation current can be achieved. As a result, more than 10 μs short circuit capability is enabled at a junction temperature of 400 K. Most importantly, the proposed RP-IGBT structure has no influence upon on-state performance and its forward voltage drop remains at 1.1 V at a current density of 200 A/cm² at 400 K.