MOS structure with hot carrier reduction

摘要

An MOS structure is disclosed which is provided with a trench in the substrate adjacent the channel region of the substrate, i.e., adjacent the area of the substrate over which the gate oxide and gate electrode are formed. The region of the substrate beneath the trench is lightly doped to provide a deeper LDD region in the substrate between the channel and the drain region so that electrons traveling through the channel to the drain region follow a path deeper in the substrate and farther spaced from the gate oxide in the region of the substrate between the source region and the drain region where high fields are encountered by electrons traveling through the channel from the source region to the drain region.