Method of Forming Fine Holes of Near Atomic Dimensions

Abstract

A method of forming small holes in certain materials is described. The material is first exposed to massive, high energy particles such as fission fragments and is then immersed in a chemical etchingsolution which dissolves the damaged material along the paths of the particles. With this technique it is possible to form holes which are as small as 25 Å in diameter and are up to ∼10 μ long. The hole diameters can be increased at will from the minimum size by continued etching. A density of up to ∼1011 holes/cm2 can be attained by a short irradiation in a typical reactor. The holes can be accurately aligned by collimating a beam of fission fragments. Fine holes have been formed in this way in a number of nonmetallic materials including glass, mica, and other silicate minerals.