International Business Machines Corporation

David W Sissenstein, Jr

Joseph G Ameen

Joseph Funari

James Richard Murray

Alan J Emerick

Peter J Elmgren

Rebecca Christine Lutsic

Vlasta A Brusic

Bahgat Ghaleb Sammakia

Joseph Donald Poole

Thomas L Miller

Mukund Kantilal Saraiya

Helen L Yeh

Dennis L Rivenburgh

Charles A Joseph

Mark Alan Brown

Samuel L Smey

Dennis L Rivenburg, Sr

Charles J Owen

Joseph A Apap

It has been discovered that organic photoresists may be quickly, coveniently, and completely stripped using a hot hydrogen atmosphere. The substrates are preferably exposed to such atmosphere utilizing a hydrogen conveyor furnace. The gases from the furnace are burned to carbon dioxide and water thereby eliminating the need to dispose of a stripping agent.

Method for stripping photoresist

It has been discovered that organic photoresists may be quickly, conveniently, and completely stripped using a hot hydrogen atmosphere. The substrates are preferably exposed to such atmosphere utilizing a hydrogen conveyor furnace. The gases from the furnace are burned to carbon dioxide and water thereby eliminating the need to dispose of a stripping agent.

Method for stripping photoresist employing a hot hydrogen atmosphere

An electronic package which includes a rigid first substrate (e.g., ceramic) having a plurality of conductive pins spacedly located therein. These pins each include one end portion extending below an undersurface of the substrate for positioning and electrically coupling within a second substrate (e.g., printed circuit board), while also including an opposite end portion which projects from an opposite, upper surface of the first substrate. These upwardly projecting end portions are designed for accommodating, in stacked orientation, a plurality of thin film, flexible circuitized substrates thereon, each of these substrates being electrically coupled to a respective pin, if desired, using a solder composition. In one example of the invention, solder hierarchy for various solders is used, one solder being used to connect the substrates and respective pins, and a second solder (having a higher melting point and different composition from the first solder) used to connect the semiconductor devices (chips) of the flexible circuitized substrates to the conductive circuitry of the substrates. Hydrogen is preferably used to effect solder reflow for the solder which couples the flexible substrates to the respective pins. In an alternate embodiment, the flexible circuitized substrates may include at least two separate conductive layers as part thereof.

Multilayered flexible circuit package

Mutlilayered flexible circuit package

An ozone safe method for stripping a silicone oil base grease from a part. The method includes the steps of providing a stripping composition of an alkylbenzene, a solution comprising a major portion of a propylene oxide derived glycol ether, and glacial acetic acid. The part to be stripped is immersed in the composition while ultrasonically agitating the composition.

Ozone safe stripping solution for thermal grease

An improved method and apparatus for making solder connections from input/output connecting pins to the circuitry on a pinned metallized ceramic substrate. A solder preform in the shape of a sphere provides the correct volume of solder. These spheres are held in position at each desired joint by a templet. The substrate, solder sphere and templet assembly is passed through a furnace in a reducing atmosphere and at a temperature to facilitate solder reflow and wetting, thus creating a sound mechanical and electrical connection between the pin and its portion of the circuitry. The method and apparatus of the invention provides joints have a high degree of reliability such that all connections are made to acceptable soldering standards, none lacking integrity. Only harmless by-products are produced in the practice of the invention, and no residue is produced which requires cleaning by means of chemical solvents and therefore is environmentally superior.

Substrate soldering in a reducing atmosphere

A curable composition containing an epoxide component and zinc oxide and use thereof.

Epoxy composition and use thereof

A solder paste for use in a reducing atmosphere is disclosed. The solder paste includes a solder powder and an alcohol binder. The reducing atmosphere serves as a flux, thereby eliminating flux residues and the problems associated therewith. Solder splattering is reduced by using a polyhydric alcoholic binder which vaporizes or decomposes before the solder liquifies during heating. The use of such a solder paste in a reducing atmosphere results in no hazardous chemical by-products and, because the solder is handled in the form of a paste, is compatible with electrical components requiring precise dimensional tolerances.

Solder paste for use in a reducing atmosphere

A workpiece is joined to a substrate by employing solder and applying diol and/or polyol and/or ether derivative thereof to the substrate. The workpiece is placed in contact with the diol and/or polyol and the resulting assembly is heated in a reducing atmosphere.

Reduction atmosphere workpiece joining

A process for reducing the chloride concentration in a system which contains an ethylenically unsaturated chlorinated hydrocarbon, water and HCl which includes providing certain nitrogen-containing compounds in the system and contacting the system with a molecular sieve. The process surprisingly is capable of regenerating the nitrogen-containing compounds employed.

Growing community of inventors

Endwell, NY, United States of America

David W Sissenstein, Jr