Producing method of thin film magnetic tape and the thin film magnetic tape

摘要

In a first forming process, by injecting a predetermined amount of oxygen gas, magnetic metal vapor 7a is deposited as a nonmagnetic underlayer on a base film F wound on one film winding roll 3B while advancing the base film F in a reverse direction (second direction) toward another film winding roll 3A along a cooling can roll 5 from a minimum incidence angle side to a maximum incidence angle side of an incidence angle controlling mask 9. In a second forming process, by injecting a extremely smaller amount of oxygen gas than in the first forming process, magnetic metal vapor 7a is deposited as a magnetic layer over the nonmagnetic underlayer while advancing the base film deposited with the nonmagnetic underlayer wound on the other film winding roll 3A in a forward direction (first direction) toward the film winding roll 3B along the cooling can roll 5 from the maximum incidence angle side to the minimum incidence angle side of the incidence angle controlling mask 9.