Patent ID: 6091103
Filing Date: 2000-07-18
Classification: H01L

Abstract:
An MOS integrated circuit comprising, in combination:a semiconductor substrate having a surface;a first region of a first conductivity type located in said substrate and in contact with said surfacesecond and third regions of a second conductivity type opposite said first conductivity type located in said first region in said substrate and in contact with said surface, said second and third regions forming a source and a drain, respectively, for a first MOS transistor;fourth and fifth regions of said second conductivity type located in said first region in said substrate and in contact with said surface, said fourth and fifth regions forming a source and a drain, respectively, for a second MOS transistor having dimensions and electrical characteristics different than those for said first MOS transistor;a sixth region said second conductivity type located in said first region in said substrate and in contact with said surface, said sixth region having a lower doping concentration than any of said second, third, fourth, and fifth regions, and said sixth region forming a control junction shared between said first and second MOS transistors;an insulating gate layer of substantially uniform thickness over each of said first, second, third, fourth, fifth, and sixth regions;conductive means coupled to said sixth region for controlling voltage on said control junction; andconductive gate means within said insulating gate layer and spanning over said first, second, third, fourth, fifth, and sixth regions for controlling a first threshold of said first MOS transistor by a first combination of voltage on said control junction and charge injected at said drain of said first I.backslash.40S transistor, and for controlling a second threshold of said second MOS transistor by a second combination of voltage on said control junction and charge injected at--at least one of said drain of said first MOS transistor and said drain of said second MOS transistor.