A method of forming at least a portion of a dual bit memory core array upon a semiconductor substrate, the method comprising performing front end processing, performing a first bitline implant, or pocket implants, or both into the first bitline spacings to establish buried first bitlines within the substrate, depositing a layer of the spacer material over the charge trapping dielectric and the polysilicon layer features, forming a sidewall spacer adjacent to the charge trapping dielectric and the polysilicon layer features to define second bitline spacings between adjacent memory cells, performing a deep arsenic implant into the second bitline spacings to establish a second bitline within the structure that is deeper than the first bit line, removing the sidewall spacers and performing back end processing.