EFFECTS OF SPUTTERED Ar PRESSURE AND SUBSTRATE TEMPERATURE ON THE MICROSTRUCTURE AND MAGNETIC PROPERTIES OF Cr/SmCo₅/Cr FILMS

Cr/SmCo₅/Cr films were fabricated by a DC facing targets magnetron sputtering. The influences of sputtered Ar pressure and substrate temperature on their microstructure and magnetic properties were investigated. Magnetic measurements indicate that the optimal substrate temperature was 450°C, and the film deposited at 2 Pa Ar pressure had the largest in-plane coercivity (2403.54 Oe). No SmCo₅ diffraction peaks except Cr (110) peak with body-centered-cubic structure were seen in all the samples by X-ray diffusion. The Needle-like grains of the film deposited at low Ar pressure were observed by atomic force microscope. The domain pattern of the film fabricated at 2 Pa Ar pressure showed more uniform. When the sputtered Ar pressure was 2 Pa, the narrowest switching field distribution (0.57) was obtained, indicating a narrower grain size distribution. The δM value was nearly zero for the film deposited at 2 Pa Ar pressure, and this indicated that there was almost noninteraction between grains.