Method for forming a memory device by utilizing variations in resistance value

摘要

On an insulating substrate are formed first aluminum interconnections. In openings formed in a silicon dioxide film are formed unit cells each consisting of a tungsten electrode and an aluminum alloy electrode containing silicon. Over the silicon dioxide film are formed a large number of linear second aluminum interconnections which are orthogonal to the first aluminum interconnections. At the individual intersections of the first and second aluminum interconnections are disposed the unit cells so as to compose a memory cell array. When a large current is allowed to flow through the unit cell, silicon in the aluminum alloy electrode moves in a direction opposite to the current flow and is precipitated in the aluminum electrode in the vicinity of the interface with the tungsten electrode, resulting in an increase in resistance value. When a large current is allowed to flow through the unit cell in the opposite direction, silicon is diffused, resulting in a reduction in resistance value. Data can be read by measuring the magnitude of the resistance value with an extremely small current and judging whether it is in a high state or in a low state.