A MOSFET FOR HIGH VOLTAGE APPLICATIONS AND A METHOD OF FABRICATING SAME

摘要

A PMOS device comprising a semiconductor-on-insulator (SOI) substrate hving a lyer (22) of insulating material over which is provided an active layer (24) of n-type semiconductor material. P-type source and drain regions (14, 16) are provided by diffusion in the n-type active layer (22). A p-type plug (28) is provided at the source region (14), which extends through the active semiconductor layer (24) to the insulating layer (22). The plug (28) is provided so as to enable the source voltage applied to the device to be lifted significantly above the substrate voltage without the occurrence of excessive leakage currents.