Local Surface Modification of ECR Sputtered Carbon Film and Its Application to Ultra High Density Data Storage

Abstract

ABSTRACTWe propose a probe storage using a carbon film deposited by electron cyclotron resonance plasma (ECR) sputtering as a recording material. Such storage has a potential to achieve an electrical data storage with small writing voltage and ultra high recording density due to super hardness and large electric conductivity of the ECR sputtered carbon (ECR-C). The ECR-C film is deposited on a silicon substrate covered by a thermal oxide. Recording experiments are performed by a conductive atomic force microscope with a gold coated tip. The electrical resistance of the film surface is decreased locally by applying voltages smaller than 2V between the film and the tip. The resistance decrease of the film by the voltage application are caused by a thermal reaction due to Joule's heat at contact portion of the film with the tip. Data bits with size of about 70nm can be formed by applying a pulse row as a writing voltage.