F含有金属−半金属系軟磁性薄膜の軟磁気特性

抄録

Co-Fe-B-F amorphous and nanocrystalline films were prepared by a high deposition rate sputtering apparatus with two opposing targets. The chemical composition of these films can be easily varied from (high B and low F) to (low B and high F) by changing the quantity of the fluorine gas. Futhermore, the content of metalloid (B+F) was found to be kept constant in amorphous structure. Soft magnetic properties were obtained for films with high B and low F content. These films had both high saturated magnetization of 1.6∼1.8 Tesla and high resistivity of 150∼1000 μΩcm. TEM observation clarified that F element decreased the size of nanocrystalline diameter from 10 nm to 5 nm in CoFeBF films with low B. The coexistence of both high B_s and high ρ is attributed to various factors of amorphous phases, constant metalloid contents of (B+F) and fine mixed phases by F element.