Development of high-rate sputtering system for Ba-ferrite thin film rigid disk for ultra high density magnetic recording

超高密度磁记录用Ba铁氧体薄膜硬盘高速溅射系统的开发

基本信息

批准号：
06555093
负责人：
MORISAKO Akimitsu
金额：
$ 8.7万
依托单位：
Shinshu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

项目摘要

In order to develope a new fabrication technique for near future high density magnetic recording media, a facing target sputtering system has been built. In this system, the ferromagnetic thin films can be deposited with high rate even when the thick iron target was used. From our previous research, it was found that the Ba-ferrite thin films can be prepared at high substrate temperature. Although the Ba-ferrite thin films with excellent characteristics for magnetic recording media, it is not suitable for practical mass prodauction. In this study, we proposed a new technique for fabrication of high density recording media with high rate.The Ba-ferrite thin films were deposited at room temperature and succsessively annealed to crystallize. In comparison with the crystallization temperature of Ba-ferrite thin films prepared both a conventional dc magnetron sputtering system and the facing targets sputtering system, it was found that the crystallization temperature of the films prepared by the facing target sputtering system is lower than of the films prepared by the dc magnetron sputtering system.The coercivities of the Ba-ferrite thin films are in the range from 2 to 3kOe and squareness ratio is about 0.8 in perpendicular direction. These vakues are suitable for high density magnetic recording media.The recording density obtained in this research is about 100kbpi for the Ba-ferrite supttered rigid disks by using a MIG type head. This value will be improved by optimizing the preparation conditons such as oxygen partial gas pressure during the deposition and annealing time.From the results of our reseach, it was found that the technique propsed in this project is applicable for practical mass production of recording media.

为了开发近期高密度磁记录介质的新制造技术，建立了面向靶溅射系统。在该系统中，即使使用厚铁靶材，也可以高速率沉积铁磁薄膜。我们前期的研究发现，Ba铁氧体薄膜可以在高衬底温度下制备。尽管Ba铁氧体薄膜对于磁记录介质具有优异的特性，但并不适合实际批量生产。在这项研究中，我们提出了一种高速率高密度记录介质的制造新技术。在室温下沉积Ba铁氧体薄膜并连续退火结晶。与传统直流磁控溅射系统和对向靶溅射系统制备的Ba铁氧体薄膜的结晶温度进行比较发现，对向靶溅射系统制备的薄膜的结晶温度低于对向靶溅射系统制备的薄膜的结晶温度。采用直流磁控溅射系统制备。Ba铁氧体薄膜的矫顽力在2～3kOe范围内，垂直方向的矩形比约为0.8。这些值适用于高密度磁记录介质。本研究中使用MIG型磁头获得的Ba铁氧体溅射刚性磁盘的记录密度约为100kbpi。通过优化沉积和退火期间的氧气分压等制备条件，可以提高该值。从我们的研究结果来看，本项目提出的技术适用于记录介质的实际批量生产。