Tunable oxide-bypassed VDMOS (OBVDMOS): breaking the silicon limit for the second generation

摘要

The research effort to lower the on-state resistance for high voltage MOSFET devices continues. We have recently reported a novel device structure termed oxide-bypassed VDMOS (OBVDMOS) that utilized the well-established oxide thickness control instead of the difficult doping control in translating the on-resistance (R_on) - blocking voltage (BV_dss) tradeoff limit beyond the conventional MOSFET silicon limit. Further enhancement on both breakdown voltage and on-resistance can be achieved by applying an external bias to the poly contact of the device. Moreover, this bias provides an independent control of adjusting breakdown voltage if it does not meet specifications due to foundry process variations.