Vapor etching of nuclear tracks in dielectric materials

US6033583A · kind A · utility

Assignee

• The Regents of the University of California · US

Inventors

• Ronald G. Musket · San Ramon, US
• John D. Porter · Meridian, US
• James M. Yoshiyama · Fremont, US
• Robert J. Contolini · Lake Oswego, US

Key dates

• Filing date: May 5, 1997
• Grant date: Mar 7, 2000
• Expiry date: May 5, 2017

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C2218/33
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A process involving vapor etching of nuclear tracks in dielectric materials for creating high aspect ratio (i.e., length much greater than diameter), isolated cylindrical holes in dielectric materials that have been exposed to high-energy atomic particles. The process includes cleaning the surface of the tracked material and exposing the cleaned surface to a vapor of a suitable etchant. Independent control of the temperatures of the vapor and the tracked materials provide the means to vary separately the etch rates for the latent track region and the non-tracked material. As a rule, the tracked regions etch at a greater rate than the non-tracked regions. In addition, the vapor-etched holes can be enlarged and smoothed by subsequent dipping in a liquid etchant. The 20-1000 nm diameter holes resulting from the vapor etching process can be useful as molds for electroplating nanometer-sized filaments, etching gate cavities for deposition of nano-cones, developing high-aspect ratio holes in trackable resists, and as filters for a variety of molecular-sized particles in virtually any liquid or gas by selecting the dielectric material that is compatible with the liquid or gas of interest.