A method of fabricating a one-time programmable (OTP) memory cell with improved read current in one of its programmed states, and a memory cell so fabricated. The OTP memory cell is constructed with trench isolation structures on its sides. After trench etch, and prior to filling the isolation trenches with dielectric material, a fluorine implant is performed into the trench surfaces. The implant may be normal to the device surface or at an angle from the normal. Completion of the cell transistor to form a floating-gate metal-oxide-semiconductor (MOS) transistor is then carried out. Improved on-state current (Ion) results from the fluorine implant.