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

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