Patent ID: 6856001

Claim:
An integrated circuit comprising: a semiconductor substrate including a first region of a predefined conductivity type; a plurality of active regions provided within said first region; a field isolation region separating at least two of said active regions, wherein said field isolation region includes an isolation trench having a depth of about 3500 Angstroms, said isolation trench further including a first area filled with a first dielectric material forming at least sidewalls of said isolation trench, and a second area filled with a second dielectric material situated within said sidewalls, wherein said first dielectric material and said second dielectric material are different; and a doped region within said first region below said second area, said doped region being of said predefined conductivity type and having a doping concentration higher than a doping concentration of said first region, wherein additional dopants in said doped region causing said higher doping concentration are displaced away from said separated active regions.