Semiconductor device with gate electrode having opposite type doping at drain end and source end including a self-aligned dwell implant

Abstract

Disclosed examples include microelectronic devices, e.g. integrated circuits, which include a source region and a drain region extending into a semiconductor substrate, the semiconductor substrate having a second conductivity type, the source region and drain region having an opposite first conductivity type. A channel region having the second conductivity type extends between the source region and the drain region. A gate electrode over the channel region has a first portion and a second portion. The first portion has the second conductivity type and a first dopant concentration. The second portion extends from the first portion toward the source region and has the second conductivity type and a second higher dopant concentration. A self-aligned implant is used to simultaneously implant dopants near the source end of the gate electrode and in the semiconductor substrate near the source region.