Abstract:
Fe-SiO
2 metal-insulator granular films with various metal volume fractions(f
v) were fabricated by RF co-sputtering.The microstructure and tunneling magneto-resistance(TMR) as well as the giant Hall effect(GHE) were systematically investigated.The Fe
0.33(SiO
2)
0.67 film exhibits the largest TMR value of-3.3% at room temperature under 1.3 T magnetic field.The sample with f
v=0.52 exhibits the largest Hall resistivity of 18.5 μΩ·cm.The Hall resistivity does not decrease much,when the Fe
0.52(SiO
2)
0.48 granular film annealed at different temperature up to 300 ℃.It indicates a good thermal stability of GHE for this film.Thus the film may be considered as a magnetic field sensor for operating temperature below 300 ℃.