Development of nano-meter head-disk interface for the Tb/in^2 class ultrahigh-recording-density information storage systems

为了实现1Tb/in2以上的面积记录密度，需要开发小于10nm的纳米磁头磁盘接口（HDI）。本研究的目的是明确新一代纳米间距HDI的设计准则。此外，我们还研究了接触滑块超薄液体润滑膜的特殊行为，并开发了飞秒激光加工在气轴承滑块表面制备纳米纹理等突破性技术，以实现未来的接触记录。所得结果总结如下：(1)利用扫描微椭偏仪实验研究了新型烷醇胺端全氟聚醚（PFPE）膜和传统润滑油膜在碳表面的扩散特性。研究了新型润滑油的表观扩散系数，并与传统润滑油进行了比较。研究结果进一步阐明了分子薄液体润滑膜的扩散特性。(2)实验研究了分子薄液体润滑膜对滑块迟滞性能的影响。换句话说，通过改变润滑盘的粘接比和润滑膜厚度来监测着陆和起飞速度的差异。结果表明，着陆速度的变化是由分子间作用力的变化引起的，而起飞速度的变化是由滑块与圆盘表面摩擦力的变化引起的。此外，明确了小于2-3 nm的超低间距下一代设计准则。(3)研究了超薄液体润滑膜对接触滑块动力学的影响，选取了端基和分子量随润滑膜厚度变化的三种类型的润滑剂。结果发现，当润滑膜厚度大于单层时，滑盘接触会导致润滑膜厚度不稳定。此外，还得出润滑膜厚度应设计为一个单层厚度区域。(4)提出并研制了一种新型接触滑块。这是由飞秒激光加工制造的纳米纹理。并利用所制备的滑块进行了接触实验。所开发的接触滑块技术在下一代HDI设计中的可行性得到了证实。少

In order to achieve more than 1Tb/in2 area recording density, it is necessary to develop nano-meter head disk interface (HDI) less than 10 nm. The goal of this research is to make clear the design guideline of next generation nano-meter spacing HDI. In addition, we studied the peculiar behavior of ultra-thin liquid lubricant films for contact sliders and developed the breakthrough technologies such as nanotextures fabricated by femtosecond laser processing on the air bearing slider surfaces to realize future contact recording. The obtained results are summarized as follows;(1)The spreading characteristics of novel alkanolamine-terminated perfluoropolyether (PFPE) films as well as conventional lubricant films on carbon surfaces were investigated and evaluated experimentally by using a scanning micro-ellipsometer. The apparent diffusion coefficients of the novel lubricants were also studied and they were compared with the conventional lubricants. As a result, the effects of end-groups on … More the spreading characteristics of molecularly thin liquid lubricant films were clarified.(2)The effects of molecularly thin liquid lubricant films on slider hysteresis behavior were investigated experimentally. In other words, the difference in the touchdown and takeoff velocities was monitored by varying the lubricant bonded ration and lubricant film thickness of the disks. As a result, it was suggested that the variation in the touchdown velocity is due to a variation in the intermolecular forces and that the variation in the takeoff velocity is caused by a variation in the friction forces between the slider and disk surface. In addition, the next generation design guideline was clarified for ultra-low spacing of less than 2-3 nm.(3)The effects of ultra-thin liquid lubricant films on contact slider dynamics were investigated, using three types of lubricant, which have different end-groups and molecular weight as a function of lubricant film thickness. As a result, it was found that the lubricant film thickness instability occurs as a result of slider-disk contacts, when the lubricant film thickness is thicker than one monolayer. In addition, it is concluded that the lubricant film thickness should be designed to be one monolayer thickness region.(4)A novel contact slider was proposed and developed. This has nanotextures fabricated by femtosecond laser processing. Contact experiments were also carried out using the fabricated sliders. The feasibility of the developed contact slider technology was confirmed for next-generation HDI design. Less