Effect of sputtering conditions, annealing and the microstructure of Cr underlayer on the magnetic properties of CoNiCr/Cr thin films

The effects of RF power P, substrate heating, and substrate bias V_b on the structure and magnetic properties of CoNiCr thin films were studied. The films were deposited on glass and Cr/glass substrates by RF diode sputtering. For films deposited at higher P and at elevated substrate temperature T_s, the grain size increased. The texture in the Cr underlayer increased at higher Ts; this was accompanied by an increase in the texture in the CoNiCr film. In-plane coercivity H _c also increased with P and T_s ; this is probably related to the increase in grain size as well as in CoNiCr texture. In the samples deposited with an applied V_b, the grains were considerably larger than in those prepared without bias. The H_c value and the magnetic domain morphology also changed with V_b; this is probably related to the increase in grain size. The H _c of CoNiCr thin films also increased following annealing in vacuum