Magnetic, electrical properties, and structure of Cr-AlN and Mn-AlN thin films grown on Si substrates

We have studied magnetic, electrical properties, and structure of Cr-AlN and Mn-AlN thin films grown on the Si substrates. Each magnetic state in Al/sub 0.93/Cr/sub 0.07/N and Al/sub 0.91/Mn/sub 0.09/N thin films changes from a paramagnetic state to a superparamagnetic state as temperature decreases. Room temperature (RT) ferromagnetism cannot be observed in each thin film. Each electrical property in Al/sub 0.93/Cr/sub 0.07/N and Al/sub 0.91/Mn/sub 0.09/N thin films becomes semiconducting, since the electrical resistivities of these thin films are higher than 10/sup 7//spl mu//spl Omega//spl middot/cm at RT. At 77 K, tunneling phenomena for the Al/sub 0.93/Cr/sub 0.07/N thin film and rectification for the Al/sub 0.91/Mn/sub 0.09/N thin film can be observed. Furthermore, the crystal structure in each thin film is also a polycrystalline structure with the preferential orientation of hcp (0001).