SEMICONDUCTOR STORAGE DEVICE, AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: To provide a semiconductor storage device which has a floating gate and a control gate and whose source and drain regions are asymmetrical and which can avoid the increase of the resistance of a bit line arranged between the floating gates in itself and besides can scale down the bit line width. CONSTITUTION: This is a manufacturing method for a semiconductor storage device consisting of forming a floating gate 3 through an insulating film 2 on a semiconductor substrate 1, and forming a sidewall spacer 8 by an insulating film at the side wall of that floating gate, digging down the semiconductor substrate to form a groove 9 using that side wall as a mask, then, forming a lightly doped layer 10 from one sidewall of the groove to the bottom by oblique ion implantation to the obtained semiconductor substrate, and also, forming a heavily doped layer 11 from the other sidewall of the groove to the bottom by reversely oblique ion implantation.