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Nanometer recording has been demonstrated with tens nanometer diameter pits and gold mounds formed on graphite and Si substrate using an atomic force microscope at atmospheric pressure. The probe is prepared by means of coating thin gold film on an SiO2birdbeak-type cantilever probe, fabricated by a Si microprocess. Applications of voltage pulses between the probe and the graphite make about 10-nm diameter pits and Au mounds. Furthermore, about 50-nm to 30-nm diameter Au mound formations on Si wafer covered with natural silicon oxide are also demonstrated. The results indicate that the technique has potentials to achieve Tera-bit/in2highly packed storage in air, and directly to write nanometer sized patterns on an insulating thin film.

The feasibility of field-evaporating metal atoms onto an insulator/conducting substrate has been investigated. Theoretical and experimental studies clarify that field evaporation is possible in an atomic force microscope (AFM) metal probe/vacuum/thin insulator/conductor configuration. Theoretically, field evaporation is easily achieved on thin SiO2insulators of less than 100 Å, though image potential and electric field weaken in the presence of an insulating layer. Experiments confirm that ultrasmall gold dots can be formed on a natural SiO2/Si substrate with a threshold voltage of around 10 V. Small dots of 15 nm diameter can be obtained.

A 3-dimensional (3-D) magnetic stray field and the surface structure have been observed using an atomic and magnetic force microscope (A/MFM) with an optical-beam-deflection force detector. Measurement is carried out by operating the microscope as a surface structure observer in constant repulsive force AFM mode. The 3-D magnetic stray field measurement is done in force gradient MFM mode with probe position control above the surface. Initial results have demonstrated that the 3-D magnetic stray field and surface structure of magneto-optical disk can be imaged simultaneously.

Surface magnetic stray fields are studied using a new force microscope with an optical beam deflection force detector. The measurements are made possible by using both a constant repulsive force control and a magnetic force gradient measurement. The microscope can simultaneously provide a magnetic force gradient image and a surface structure image. Initial results demonstrate that the surface magnetic stray field and the surface structure image of a magneto-optical disk can be obtained. The new method provides feasibility of measuring the surface magnetic stray field.