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A new handling technique of ultrafine particles, called “ultrafine-particle beam deposition,” was applied to the preparation of various films, such as of Ag, Au, Cu, Fe, Ni, Pt, Ta and W. The mechanism of deposition and coalescence of ultrafine particles is thought to be described by the diffusion process. The high surface activity of ultrafine particles was preserved in this handling technique, and the obtained films had low electric resistances close to those of corresponding bulk metals.

In an attempt to demonstrate a wider applicability of our handling technique of ultrafine particles, called “ultrafine particles beam deposition,” the following procedures were applied to prepare films composed of elements such as Fe, Si and/or O, which possess thermoelectric properties: (i) preparation of iron silicide alloy film derived from FeSi2+x (-1

A new approach using a system in vacuo with a dynamic gas flow named “ultrafine particles beam deposition,” was proposed as a technique for handling ultrafine particles. To create a gas beam flow, three types of sampling and transportation methods for ultrafine particles were tested. In these sampling and transportation methods, the sampling method using a skimmer and differential pumping gave the best results since it enables sampling of hot ultrafine particles soon after they are produced and carries them without collision in a directional gas flow. A narrow size distribution for ultrafine particles ranging from 3 nm to 13 nm could be obtained in the case of ultrafine Fe particles. As a result, the deposited film obtained using such small ultrafine particles showed a metallic luster as grown and characteristics such as specific electric resistance, coercive force and crystalline property similar to those of bulk Fe metal.