The United States of America As Represented by the Administrator of the

United States of America As Represented by the Administrator of Nasa

Arthur N Curren

Robert F Roman

Kenneth A Jensen

James S Sovey

Edwin G Wintucky

Ralph Forman

The present invention is directed to a method and apparatus for producing a highly-textured surface on a copper substrate with only extremely small amounts of texture-inducing seeding or masking material. The texture-inducing seeding material is delivered to the copper substrate electrically switching the seeding material in and out of a circuit loop.

Substrate with low secondary emissions

Method and apparatus for producing a substrate with low secondary

A very thin layer of highly textured carbon is applied to a copper surface by a triode sputtering process. A carbon target 10 and a copper substrate 12 are simultaneously exposed to an argon plasma 14 in a vacuum chamber. The resulting carbon surface is characterized by a dense, random array of needle-like spires or peaks which extend perpendicularly from the copper surface. The coated copper is especially useful for electrode plates in multistage depressed collectors.

Textured carbon surfaces on copper by sputtering

A specially textured surface of pyrolytic graphite exhibits extremely low yields of secondary electrons and reduced numbers of reflected primary electrons after impingement of high energy primary electrons. Electrode plates of this material are used in multistage depressed collectors. An ion flux having an energy between 500 eV and 1000 eV and a current density between 1.0 mA/cm.sup.2 and 6.0 mA/cm.sup.2 produces surface roughening or texturing which is in the form of needles or spires. Such textured surfaces are especially useful as anode collector plates in high efficiency electron tube devices.

Ion sputter textured graphite electrode plates

A specially textured surface of pyrolytic graphite exhibits extremely low yields of secondary electrons and reduced numbers of reflected primary electrons after impingement of high energy primary electrons. An ion flux having an energy between 500 eV and 1000 eV and a current density between 1.0 mA/cm.sup.2 and 6.0 mA/cm.sup.2 produces surface roughening or texturing which is in the form of needles or spines. Such textured surfaces are especially useful as anode collector plates in high efficiency electron tube devices.

Growing community of inventors

North Ridgeville, OH, United States of America

Arthur N Curren