From computers " development within these years , we can see that hard disks have a trend to smaller disk diameters ( which allows more rapid design and integration ) and more capacity and faster rotate speed . it will require substrate materials have high mechanical performance and good flatness , but the former nip / al substrate cannot accommodate to these change 纵观近年来硬盘的发展趋势,硬盘正朝着更高的容量、更快的速度、更小的体积快速发展,要求基板材料具有更好的力学性能和平整的表面,原先的nip al基板已经无法适应这一变化。