A memory device array with spaced apart parallel isolation regions formed in a semiconductor substrate, with an active region between each pair of adjacent isolation regions. Each isolation region includes a trench formed into the substrate surface and an insulation material formed in the trench. Portions of a top surface of the insulation material are recessed below the surface of the substrate. Each active region includes a column of memory cells each having spaced apart first and second regions with a channel region therebetween, a floating gate over a first channel region portion, and a select gate over a second channel region portion. The select gates are formed as continuous word lines extending perpendicular to the isolation regions and each forming the select gates for one row of the memory cells. Portions of each word line extend down into the trenches and disposed laterally adjacent to sidewalls of the trenches.