Magnetic and recording characteristics of Cr, Ta, W and Zr pre-coated glass disks

Magnetic and recording characteristics of CoCrPt/CrTi media which are deposited on Cr, Ta, W and Zr pre-coated glass disks, are examined. High S* was obtained on Ta and Zr. The largest output signal and the lowest DC-erase and recording noise were obtained on Ta. The recording noise on Zr pre-coated disk was second lowest. When the pre-coating thickness is increased, H_c on Ta increased by 700 Oe but the H_c increase on Zr was small. On the other hand, the DC-erase noise stayed constant and the recording noise decreased on Ta and both DC-erase noise and recording noise slightly increased on Zr. The δM measurement revealed that the increase of Ta thickness caused the reduction of magnetic interaction between CoCrPt crystals. Strong Co(110)/Cr(100) orientation was observed on Ta and no major difference in crystal grain size was observed between Ta, Zr pre-coated media. The low DC-erase noise characteristics on Ta pre-coating would be attributed mainly to strong in-plane c-axis orientation