Vertical integration of a spin dependent tunnel junction with an amorphousSi diode for MRAM application

This work demonstrates the successful vertical integration of magnetic tunn eling junctions with hydrogenated amorphous silicon (a-Si:H) diodes. In the finished device over 11.4% current change was measured when the junction f ree layer is switched in an external magnetic field, applying 0.86V to the tunnel junction-diode series. In the integrated device, the TMR signal of t he junction measured alone was 25.3% at 7mV bias, demonstrating junction ro bustness and process compatibility. The Delta I/I signal of the junction-di ode series was optimized by changing the junction resistance. With the pres ent a-Si:H technology, an RC time constant below 25ns is calculated, higher than the 2.5ns estimated for the tunneling junction.