ESD reliability impact of p+ pocket implant on double implanted NLDD MOSFET

An ESD study was conducted on a process using an arsenic NLDD, a boron pocket implant, and an 90 angstrom gate oxide. Increasing the boron pocket and arsenic NLDD implant doses increased the ESD robustness of the NMOST. However, heavier B11 pocket implants of 1.5E13 atoms/cm/sup 2/ were found to create parasitic n-p-n bipolar transistors under the n-well tap diffusions, increasing n-well tap resistance.