Spin dependent tunneling memory

The invention relates to a ferromagnetic thin-film based digital memory, said memory comprising: a plurality of bit structures interconnected with information retrieval circuitry having a plurality of transistors so that each said bit structure has a said transistor electrically coupled thereto that selectively substantially prevents current in at least one direction along a current path through that bit structure, each said bit structure comprising: an electrically insulative intermediate layer, said intermediate layer having two major surfaces on opposite sides thereof; and a memory film of an anisotropic ferromagnetic material on each of said intermediate layer major surfaces having switching thresholds for magnetizations of said film adjacent each of said intermediate layer major surfaces that differ in value for a switching of these magnetizations from both being directed initially at least in part in substantially a common direction to being directed at least in part in substantially opposite directions versus a switching from being directed initially at least in part in substantially opposite directions to both being directed at least in part in substantially a common direction; and a plurality of word line structures each having a pair of word line end terminal regions adapted to conduct electrical current in at least one direction therethrough, each of said pairs of word line end terminal regions having an electrical conductor electrically connected therebetween which is located across an electrical insulating layer from said memory film on one of said major surfaces of said intermediate layer of a corresponding one of said bit structures.