Paper Title
Effect of High-voltage NLDMOS in the Drain-side with Parasitic Schottky Diode and N+ Area Modulation on ESD Capability

Abstract
Semiconductor hetero junction is a junction formed by two different materials, usually a metal-to-semiconductor junction. In this paper, the heavily doped N+ of drain-side in an nLDMOS was removed or partially removed, so that LDMOS is equivalent to the formation of additional (partial) hetero junction components in the drain-side of the nLDMOS, we will investigate its effect on ESD electrostatic protection. From the TLP measure result, the optimized secondary breakdown current of nLDMOS can be increased from 2.26 A to 4.281 A (improved 89.4%). It can be found that from removing the drain-side heavily doped region in LDMOS, LDMOS devices are equivalent with a large series hetero junction device, they are indeed very effective in improving the ESD reliability of nLDMOS devices without any increasing the layout cell area. Keywords - Electrostatic Discharge (ESD), Heterojunction, Holding Voltage (Vh), N-channel Lateral-diffused MOSFET (nLDMOS), Schottky Diode, Secondary Breakdown Current (It2), Transmission-line Pulse (TLP), Trigger Voltage (Vt1).