Study on Development of High Rate Sputtering Apparatus for Producing Perpendicular Magnetic Recording Tape.

以钴铬薄膜磁带为介质的垂直磁记录系统是实现超高密度磁记录最有前途的候选系统之一。为了利用Co - Cr薄膜制备这种记录磁带，需要在聚合物磁带基片上开发连续薄膜涂层系统。面对目标溅射（FTS）系统在薄膜沉积方面具有许多优点，如在低工作气压下，无需等离子体轰击，薄膜沉积速率高。本研究开发了具有作用涂层的FTS系统。该机可在氩气压力低至0.1mTorr的条件下工作，这是传统溅射系统无法工作的。在1000A/min的高沉积速率下，可以制备出c轴取向良好的Co-Cr薄膜，不会引起带基板的翘曲和变形。沉积薄膜的内应力随工作气压的变化而变化，在0.5mTorr左右制备的薄膜内应力为零。从摩擦学研究的角度来看，这种无应力薄膜是一种很好的柔性记录介质。制备了由200a厚的Co-Cr层和50a厚的碳层构成的多层膜，以构建只有细颗粒的膜。结果表明，仅由Co-Cr层构成的多层结构是控制垂直矫顽力的方法之一。同时研究了两步沉积法在作用涂层体系中的应用，避免了沉积区边缘部分结晶度下降和c轴倾斜角过大的问题。研究了沉积颗粒与衬底垂直入射形成的初始层厚度仅为100a。这意味着FTS系统可以在不降低沉积速率的情况下实现超高速率沉积。

One of the most promising candidate system to achieve ultra high density magnetic recording is perpendicular magnetic recording system using Co-Cr thin film tape media. It is required to develop the continuous thin film coating system on polymer tape substrate in order to prepare such recording tape using Co Cr thin film. Facing Targets Sputtering (FTS) system has many merits in depositing thin film, such as high rate film deposition at low working gas pressure without plasma bombardment. The FTS system with role coating system has been developed in this study. This machine worked in the condition of Ar gas pressure as low as 0.1mTorr where conventional sputtering system can not work. Co-Cr thin film with good c-axis orientation can be prepared without any warp nor transformation of tape substrate caused by heat at high deposition rate of 1000A/min.. Internal stress of deposited films changed with working gas pressure, and indicates zero for films prepared at about 0.5mTorr. This stress-free thin film is very good for flexible recording media from the stand point of tribological investigation. Multilayered films constructed with 200A-thick Co-Cr layers and 50A-thick Carbon layers have been prepared so as to construct films with only fine particulates. It is demonstrated that multilayered structure constructed only Co-Cr layers becomes one of the method for controlling perpendicular coercivity. It is also investigated that two step deposition method in role coating system is very useful to avoid the degradation of crystallinity and large c-axis canting angle which occurs at the edge part of deposition area. It is investigated that Only 100A-thick initial layer constructed with depositing particles with vertical incidence to the substrate. This result means FTS system can achieve ultra high rate deposition without reduction of deposition rate.