Accurate Dose Control in High Pressure Condition on Medium Current Ion Implanters

On ion implantation, outgassing from photoresist coating wafer can induce a significant dose shift which can result in fluctuations of device characteristics within a wafer and/or in wafer-to-wafer. Pcomp, which is a system that compensates beam currents as a function of the beam line pressure, improves dose accuracy in implantation onto photoresist-coated wafers. Pcomp is effective even for medium current ion implanters as well as for batch-type implanters. It is also inevitable to use Pcomp on medium current implanters with high power beams, especially at a high energy region.