一种用于高密度信息存储中数据读取的新方法的理论和实验研究

摘要

通过测量压电悬臂梁的等效电容来检测悬臂梁的振动信息,以应用于基于扫描探针技术的高密度信息存储中进行数据读取.在压电悬臂梁的PZT压电层上施加交流电场使其工作在共振状态,并使其自由端与存储介质进行周期性的接触.当悬臂梁的自由端扫描到数据点时,其自由端的振幅和所受到的外力将发生变化,进而引起PZT压电层的介电常数发生变化.因此,通过检测悬臂梁上压电层的等效电容变化,便可以得到悬臂梁的振幅改变量,从而实现了对存储介质上数据的读取.实验结果表明,该可以实现1nm的位移检测分辨率.%A novel data readout method based on equivalent capacitance detection is developed for SPM-based high density data storage. A self-excited vibrating piezoelectric cantilever is used for data readout at its resonant frequency by cyclic contact mode. When the cantilever tip scans over the data bits, an additional external stress on the PZT layer induced by tip deflection leads to the changes of the dielectric constant as well as the capacitance of the cantilever. The experimental results indicated that the capacitance detection method has a displacement resolution of about 1 nm.