Field effect semiconductor devices and methods of fabrication thereof.

摘要

A multi-cellular power field effect semiconductor device (100) includes a tungsten silicide (134)/polysilicon (132)/oxide gate electrode (131) stack with low sheet resistance. Preferably, a layer of tungsten (136) is also disposed in intimate contact with the source region of the device. This tungsten layer (136) is self-aligned with respect to the aperture in the gate electrode (131) through which the source region is diffused. The presence of this tungsten layer greatly reduces the resulting ohmic contact resistance to the region. If desired, a tungsten layer can also be disposed in contact with the drain region (114) of the device, again, to lower ohmic contact resistance. The device has substantially improved operating characteristics. Novel processes for producing the device are also described.