Cr underlayer가 Sputter 증착한 CoNiCr/Cr, CoCrTa/Cr longitudinal 자기기록매채의 미세구조와 자성특성에 미치는 영향

Effects of Cr Underlayer on Microstructural and Magnetic Properties of Sputtered CoNiCr/Cr, CoCrTa/Cr Films

CoNiCr/Cr and CoCrTa/Cr for longitudinal magnetic recording media were. prepared on Coming 7059 glass by RF magnetron sputtering. The thickness of Cr underlayer was varied from 500 to $3000{\AA}$ and. that of magnetic layer was $700{\AA}$. Coercivity and squareness were measured using V.S.M.(vibrating sample magnetometer). The coercivity of films increased with increasing Cr thickness when the films were unannealed. The coercivity of the films annealed in a 10 mtorr vacuum increased initially with annealing time and then saturated with further increase in annealing time. The coercivity value difference between the unannealed and annealed films increased with increasing the thickness of Cr underlayer No significant change was found in squareness after anneal, regardless of Cr underlayer thickness.