Low Temperature Electric and Magnetic Studies of Permalloy Thin Films

Y. D. Yao；C. H. Ho；Y. Liou；S. F. Lee；I. Klik；C. K. Lo

Chinese Journal of Physics

36卷2S期（1998 / 04 / 01）

463 - 467

英文

Permalloy thin films with thickness between 5 nm and 400 μm were grown on Si( 100) wafers by DC magnetron sputtering. Electric resistivity and magnetoresistance were studied between 4 and 300 K. With decreasing temperature the electric resistivity decreases, but the magnetoresistance (MR) ratio is found to increase. The MR ratio at room temperature varies between 0.3 and 3.1% for samples with thickness between 5 nm and 400 pm. The maximum MR ratio measured at 4.2 K is approximately 7%. The grain size increases with increasing thickness of the films and we show that this effect leads to a decrease in the electric resistivity and to an increase in the MR ratio.