PREPARATION OF PERPENDICULAR MAGNETIC RECORDING MEDIA BY ELECTROLESS PLATING METHOD

以化学镀法制备高性能薄膜在垂直磁记录系统高密度磁记录介质中的应用为基础，研究了化学镀法制备高性能薄膜的方法和评价。垂直各向异性薄膜由CoNiReP和CoNiReMnP合金的钴合金镀膜实现。最后，采用一种新的化学镀液制备了适合于垂直记录的CoNiP三元合金。具有结晶和非晶NiP底层的底层的钴合金记录介质分别显示出所谓的双层（输出电压的增强）和增强钴合金的结晶度的效果，其能够记录更高的密度。当使用NiWP镀层底层时，这两种效果都产生了，并且通过具有NiWP底层的钴合金介质建立了非常高的记录密度，例如300kFRPI输出信号的第三峰值。确定了300埃的最佳底层厚度。此外，当使用NiMoP底层时，钴合金介质自动形成初始软层，初始软层的厚度由NiMoP底层的Mo浓度控制，通过SEM、TEM、RHEED和极局域EDX等分析技术，并结合湿法刻蚀方法，镀介质的结构建议为偏聚沉积条件，即富Co区的磁性部分分散在非晶态NiP结构的非磁性区。这种分离条件可以增强磁畴的隔离度，使记录更高的磁记录密度成为可能。最后，我们提出了环形头组合垂直磁记录介质的指导原则。

The formation and evaluation on high function thin films by an electroless plating method were studied on the basis of the application of them to high density magnetic recording media of perpendicular magnetic recording system. The perpendicular anisotropy thin film is realized by the cobalt alloy plating films of CoNiReP and CoNiReMnP alloys. Moreover, the ternary CoNiP alloy suitable for perpendicular recording was finally developed by a new electroless plating bath. The cobalt alloy recording media with the underlayer of crystallized and amorphous NiP underlayers show the effects of so-called double layer (enhancement of output voltage) and of enhancing crystallinity of cobalt alloy which was able to record the higher density, respectively. When using NiWP plating underlayer, the both effects are produced and the very high recording density such as 300kFRPI output signal of the third peak is established by the cobalt alloy media with NiWP underlayer. The most suitable thickness of the underlayer is confirmed to be so thin layer of 300 A. Moreover when using NiMoP underlayer, the cobalt alloy medium is automatically formed with an initial soft layer and the thickness of the initial soft layer is controlled by the Mo concentration of NiMoP underlayer.With some analytical techniques of SEM, TEM, RHEED and very local area EDX, and also with a combination of wet etching method with them, the structure of the plated media is suggested to be the segregated deposition conditions that the magnetic parts of Co rich area are scattered in the non-magnetic area of an amorphous NiP structure. Such an segregated condition can enhance an isolation of magnetic domains and it makes it possible to record the higher magnetic recording density.Finally, we proposed a guiding principle of perpendicular magnetic recording media with a combination of ring-type head.