Fabrication of L11 Phase CoPt Film on Glass Substrate With [Co/Pt] Multilayer Structure

L1₁ CoPt hlms were fabricated on glass substrate with Pt underlayer by alternate deposition of Co and Pt hlms. The effect of individual Co and Pt thickness, and the total CoPt hlm thickness on structural and magnetic properties were investigated. In this paper, the experiments were divided into two parts. In the hrst part, [(x)Co₁/(x)Pt_0.75]_n hlms with varying Co and Pt hlms were deposited and overall film thickness was kept at 7 nm. In the second part, [(x)Co₁/(x)Pt_0.75]_n hlms with different total thickness were deposited. In the first case, the coercivity (H_c⊥), squareness (S_⊥), and perpendicular magnetic anisotropy are found to deteriorate with increasing Co and Pt layer thickness due to longer diffusion length. In the second case, the higher H_c⊥ with value of 110 kA/m is obtained in [(x)Co₁/(x)Pt_0.75]_n film, and increasing total thickness of film results in lower H_c⊥. Therefore, it is demonstrated that the CoPt film sputtered by multilayer type with lower thicknesses of Co and Pt layer promotes the formation of L1₁ structure with excellent perpendicular magnetic properties.