Nano-contacted magnetic memory device

A method of writing data in a MRAM unit which comprises a plurality of transistors on a substrate, each of said plurality of transistors being a field-effect transistor and comprising first and second source/drain electrodes and a gate electrode, a plurality of active areas defined in a common memory block which is electrically connected to each of said first source/drain electrodes through in each case one of a plurality of contacts, a common electrode electrically contacting said plurality of contacts through said common memory block, and a common digital line provided electrically isolated next to said common electrode on an opposite side of said common electrode with respect to said common memory block, said common memory block comprising a ferromagnetic recording layer, a free magnetic reading layer, a non-magnetic space layer between said ferromagnetic recording layer and said free magnetic reading layer, said method comprising:

• controlling said plurality of transistors for electrically activating a corresponding one of said plurality of contacts, thereby electrically activating a respective active area of said plurality of active areas, said activated respective active area serving as effective magnetoresistive element;
• raising the temperature of said ferromagnetic recording layer at said effective magnetoresistive element to approach or exceed its critical temperature independently of other active areas, thereby reducing the coercitivity of said ferromagnetic recording layer at said effective magnetoresistive element;
• and
• writing a magnetization state representing a bit of said data in said ferromagnetic recording layer at said effective magnetoresistive element by passing a current through said common digital line.

A method of performing a read operation in a MRAM unit which comprises a plurality of transistors on a substrate, each of said plurality of transistors being a field-effect transistor and comprising first and second source/drain electrodes and a gate electrode, a plurality of active areas defined in a common memory block which is electrically connected to each of said first source/drain electrodes through in each case one of a plurality of contacts, a common electrode electrically contacting said plurality of contacts through said common memory block, and a common digital line provided electrically isolated next to said common electrode on an opposite side of said common electrode with respect to said common memory block, said common memory block comprising a ferromagnetic recording layer, a free magnetic reading layer, a non-magnetic space layer between said ferromagnetic recording layer and said free magnetic reading layer, said method comprising:

• controlling said plurality of transistors for electrically activating a corresponding one of said plurality of contacts, thereby electrically activating a respective active area of said plurality of active areas, said activated respective active area serving as effective magnetoresistive element;
• applying a current through said common digital line, thereby adjusting all magnetization states in said free magnetic reading layer;
• and
• determining the magnetization state of said ferromagnetic recording layer at said effective magnetoresistive element, wherein the resistance states of said ferromagnetic recording layer at said effective magnetoresistive element are dependent on the relative angles between the magnetization vectors of said ferromagnetic recording layer at said effective magnetoresistive element and of said free magnetic reading layer.