@ A semiconductor memory device, such as a MOS dynamic RAM device, having memory cells each comprising a transfer gate transistor (10) and a capacitor (11). The capacitor (11) is a so-called groove-type capacitor and has a conductive layer (18) formed on an insulation film (17) attached to the inside surface of a groove (16) formed on a semiconductor substrate (12). The conductive layer (18) is electrically coupled to the source (14) of the transfer gate transistor (10). The capacitance of the capacitor (11) is formed between the conductive layer (18) and a second conductive layer (20) formed on the conductive layer (18) via an insulation film (19), and/or between the conductive layer (18) and the semiconductor substrate (12).