Room temperature ferromagnetism in Cr-doped hydrogenated amorphous Si films

Ferromagnetism above room temperature was observed in Cr-doped hydrogenated amorphous silicon films deposited by rf magnetron-sputtering. Structure analysis reveals that films are amorphous without any detectable precipitates up to the solubility limit 16 atomic percentages of Cr. Experimental results suggest that hydrogenation has a dramatic influence on magnetic properties, electrical conductivity and carrier concentration in the thin films. Pronounced anomalous Hall effect and magnetization curve both suggest the origin of the ferromagnetism may arises from percolation of magnetic polarons.