Planar SONOS gate power MOSFET with an ultra-shallow body region

Abstract

In this paper, a planar silicon-oxide-nitride-oxide-silicon (SONOS) gate power MOSFET (SG-MOSFET) with a 0.3 μm ultra-shallow heavily doped p-body region is presented. The ultra-shallow body provides a much reduced parasitic JFET resistance, resulting in a low specific on-resistance of 18 mΩ·mm2 for a planar device. At the same time, no punch-through problem is caused by the ultra-shallow body, and the avalanche breakdown voltage of the device is 29.5 V. The product of the on-resistance and gate charge of the ultra-shallow body SG-MOSFET is 43 mΩ·nC at VGS = 4.5 V. The non-optimized performance obtained for this structure is comparable to that of trench power MOSFETs fabricated using more advanced technologies.