Psi Star

Other

Dionex Corporation

James F Battey

Norvell J Nelson

Daniel J Barnett

Richard F Reichelderfer

Perry A Diederich

Richard L Bersin

Joseph M Welty

Copper etching process and product particularly suitable for use in the manufacture of printed circuit boards. The copper is etched in a liquid etchant, and the crystal structure of the copper is selected and carefully controlled to provide an anisotropic etch and a vertical-to-lateral etching ratio greater than 1:1. In one disclosed embodiment, the etching solution contains nitric acid, copper nitrate or sulfuric acid, a polymer and a surfactant, and the copper has a top surface crystal structure with predominantly (111) orientation. In another disclosed embodiment, the etching solution contains hydrogen peroxide and sulfuric acid, and the copper foil has a top surface crystal structure with predominantly (311) and (511) orientations and/or (111) orientation. A printed circuit board manufactured in accordance with the invention has a copper foil with a crystal structure selected to provide anisotropic etching and a vertical-to-lateral etching ratio greater than 1:1 with a given etching solution bonded to a substrate, with portions of the copper foil being etched away by the etching solution to form the desired foil pattern.

Copper etching process and product

Copper etching process and product particularly suitable for use in the manufacture of printed circuit boards. The copper is etched in a liquid etchant, and the crystal structure of the copper is selected and carefully controlled to provide an anisotropic etch and a relatively high vertical-to-lateral etching ratio. In one disclosed embodiment, the etching solution contains nitric acid, copper nitrate or sulfuric acid, a polymer and a surfactant, and the copper has a top surface crystal structure with predominantly (111) to (200) orientations and relatively little (220) orientation. In another disclosed embodiment, the etching solution contains hydrogen peroxide and sulfuric acid, and the copper foil has a top surface crystal structure with predominantly (311) and (511) orientations and/or (111) and (200) orientations. A printed circuit board manufactured in accordance with the invention has a copper foil with a crystal structure selected to provide anisotropic etching and a relatively high vertical-to-lateral etching ratio with a given etching solution bonded to a substrate, with portions of the copper foil being etched away by the etching solution to form the desired foil pattern.

A plasma reactor comprises a working chamber that has at least one entry port. The working chamber is adapted to receive at least one article The entry port is adapted to receive a working gas into the working chamber. An electrical energy generator is provided. The plasma reactor includes at least one pair of electrodes which are positioned adjacent the working chamber entry port. The electrodes, which are connected to the generator, create an electric field adjacent the entry port that converts the working gas into a working plasma for interacting with a material of the article. The article to be processed is placed in a part of the working chamber which is free from electric fields. An electric field-free region downstream of the plasma generating region is provided in which the article is positioned. A plasma constraint member is provided to direct substantially all of the plasma flow through the articles held on said constraint member. The plasma reactor can be used to clean organic scums, films or epoxy glass from circuit boards and magnetic recording discs. With ammonia as the plasma, the reactor can be used to case harden alloys.

Plasma reactor and methods for use

Copper etching process and product particularly suitable for use in the manufacture of printed circuit boards. The copper is etched in a liquid etchant, and the crystal structure of the copper is selected and carefully controlled to provide an anisotropic etch and a relatively high vertical-to-lateral etching ratio. In one disclosed embodiment, the etching solution contains nitric acid, copper nitrate or sulfuric acid, a polymer and a surfactant, and the copper has a top surface crystal structure with predominantly (111) and (200) orientations and relatively little (220) orientation. In another disclosed embodiment, the etching solution contains hydrogen peroxide and sulfuric acid, and the copper foil has a top surface crystal structure with predominantly (311) and (511) orientations. A printed circuit board manufactured in accordance with the invention has a copper foil with a crystal structure selected to provide anisotropic etching and a relatively high vertical-to-lateral etching ratio with a given etching solution bonded to a substrate, with portions of the copper foil being etched away by the etching solution to form the desired foil pattern.

Reactor and method for removing a material such as copper from a substrate such as a printed circuit board, utilizing a liquid etchant. The work to be etched is placed in a narrow channel, and the etchant is pumped rapidly across the surface of the work at a rate such that the composition of the etchant does not change significantly from one side of the work to the other.

Liquid etching reactor and method

Process and apparatus for carrying out a reaction, such as etching aluminum, in the glow discharge of a gas plasma. The plasma is formed between a pair of closely spaced electrodes, and a distributed impedance is provided in series with the plasma to assure uniform distribution of the ionizing current and the glow discharge of the plasma throughout the region between the electrodes.

Growing community of inventors

Los Altos, CA, United States of America

James F Battey