Thickness dependent structural, morphological, and magnetic properties of PLD grown CoFe thin film

The objective of the present investigation is to optimize the thickness of Pulse Laser Deposition (PLD)-grown CoFe thin films to achieve minimal effective Gilbert damping (alpha eff) for potential spintronics applications. The effect of the thickness (5-30 nm) of CoFe ultra-thin films on the Si/SiO2 substrate on the structural, morphological and magnetic properties has been reported. The X-ray diffraction (XRD) peak at 44.5(degrees) shows the growth of CoFe along the (110) crystal plane. A nearly square M-H loop with high saturation magnetization (Ms) suggests good crystalline growth of CoFe film. A high coercive field (Hc) observed in the thinnest 5 nm film is due to defects such as dislocations and stacking faults that appear at very low thickness. These defects gradually decrease with an increase in CoFe film thickness, as evident from a decrease in the Hc and an increase in the Ms. The value of alpha eff is largest for the thinnest 5 nm film due to defects and magnetic inhomogeneities present at this thickness. The damping is reduced by approximately one-third for the 10 nm thin film in comparison to the 5 nm film, which signifies a good quality film with fewer disorders.