3D Interconected Die Stack

A 3D interconnected die stack 200 transferring data signals between first and second die structures 202/204 (or 204/202), comprising a synchronising spintronic nanotorque oscillator 220 on first die to generate a magnetic field based on input signal sourced from a signal generator; and, on the second die a receiver 220 comprising a magnetic random-access-memory MRAM receptor (sensor); the memory receptor coupled to a read array for reading memory state. Transmitter may generate a microwave field from the spintronic nanotorque oscillator. The receiver may use a magneto resistive effect to capture and convert the microwave field into a data-signal. The transmitter may comprise the spin torque oscillator (302 fig 3) connected to a phase locked loop PLL 304 module having reference signal (312) at input (306). The receiver may further include a magneto-resistive random access memory element (magnetic tunnel junction MTJ as part of Spin Torque Transfer (STT) magneto-resistive random access memory device) which comprises a free layer (406 fig 4), a fixed layer (408) and a sandwich barrier (410) tunneling layer. The first die for example may comprise a digital domain coupled via multiple bus tracks to the spin nanotorque oscillator. The magnetic field (microwave field) operates over distance d and the receiver is within the field allowing detection. The receiver determines the state of the magnetic field to extract a digital state clocked back into a digital domain. Additionally both transmitter and receivers may be provided on each die.