Read/Write Mechanisms and Data Storage System using Atomic Force Microscopy and MEMS Technology

Hyunjung Shin, Seungbum Hong, and Jong Up Jeon

Micro System Lab., Samsung Advanced Institute of Technology, P.O. Box 111, Suwon, Korea 440-600

Information storage system that has a potentially ultrahigh storage density based on the principles of AFM (Atomic Force Microscopy) has been developed. MEMS (Micro Electro-Mechanical Systems) technology plays a major role in integration and miniaturization of the AFM, electronics as well as control units. X- and y-axis electrostatic planar actuator that is responsible for the parallel operation of large two-dimensional AFM cantilever array is also demonstrated. Its potential application for ultrahigh storage density has been demonstrated by AFM with a piezoresponse mode to write and read information bits in ferroelectric Pb(Zr_xTi_1-x)O₃ films. With this technique, bits as small as 40 nm in diameter have been achieved, resulting in a data storage density of simply more than 200Gb/in². Relevant issues, i.e. bit (induced ferroelectric domains) size dependence on applied voltage and pulse width as well as retention characteristics of the formed bits, are to be discussed in detail.