Non-volatile memory elements

A non-volatile memory element, which includes a transistor and stores data by changing its threshold voltage, includes a semiconductor substrate, an electrically chargeable floating gate electrode layer above the main surface of the substrate, another electrically chargeable floating gate electrode layer above the main surface of the substrate, and a control gate electrode layer above these floating gate electrode layers, separated from them by an insulating film such that the voltage of the control gate electrode layer controls charged conditions of the floating gate electrode layers which are insulated from each other and disposed along the direction of the current flow in the transistor.