Ion Track Technology

PhysicsConsult

Reimar Spohr

PostHeaderIcon Abstract

Etch rate determination from percolation threshold. Reimar Spohr. United States Patent 4725332 (1983)

During ion track etching the diameter of the individual etch pits increases linear in time. The corresponding etch pit areas, however, increase quadratic in time. Due to the quadratic increase, the critical point at which a perforated structure dissolves (a kind of "percolation point") is reached at a rather well defined etch pit diameter. The observation of the dissolution thus can be used to determine the etch rate, for example when exploring a new etch medium.