International Business Machines Corporation

Richard Stuart Zarr

Voya Rista Markovich

Gary Paul Vlasak

Douglas Oliver Powell

Kenneth Michael Fallon

Charles F Carey

Ajit Kumar Trivedi

Warren A Alpaugh

George Frederick Walker

Carlos Juan Sambucetti

Anilkumar Chinuprasad Bhatt

Anthony P Ingraham

Jaynal Abedin Molla

Robert Douglas Edwards

William J Amelio

Eric P Dibble

Paul Joseph Hart

Steven L Hanakovic

Gary K Lemon

Richard Gerald Murphy

Richard C Senger

Daniel S Niedrich

Leo Raymond Buda

Kenneth R Czarnecki

George John Saxenmeyer, Jr

Bette Jaye Whalen

A method of testing semiconductor chips is disclosed. The individual semiconductor chips have I/O, power, and ground contacts. In the method of the invention a chip carrier is provided. The chip carrier has contacts corresponding to the contacts on the semiconductor chip. The carrier contacts have dendritic surfaces. The chip contacts are brought into conductive contact with the conductor pads on the chip carrier. Test signal input vectors are applied to the inputs of the semiconductor chip, and output signal vectors are recovered from the semiconductor chip. After testing, the chip may be removed from the substrate. Alternatively, the chip may be bonded through the dendritic conductor pads to the substrate after successful testing.

Method and apparatus for in-situ testing of integrated circuit chips

A printed circuit board or card for direct chip attachment that includes at least one power core, at least one signal plane that is adjacent to the power core, and plated through holes for electrical connection is provided. In addition, a layer of dielectric material is adjacent the power core and a circuitized conductive layer is adjacent the dielectric material, followed by a layer of photosensitive dielectric material adjacent the conductive layer. Photodeveloped blind vias for subsequent connection to the power core and drilled blind vias for subsequent connection to the signal plane are provided. Also provided is process for fabricating the printed circuit board or card for direct chip attachment.

Method of making printed circuit board

Small, closely spaced deposits of solder materials may be formed with high volumetric accuracy and uniformity of shape by depositing a layer of conductive material over surfaces of a dielectric layer having apertures or recesses (e.g. blind apertures) and conductors and/or pads exposed by those apertures or recesses, masking regions of the conductive material with a further patterned dielectric layer, electroplating solder materials onto regions of the conductive material exposed by the mask, removing the mask and portions of the conductive material by selective etching and reflowing solder away from at least a portion of the surfaces of the apertured dielectric layer. Uniformity of electroplating within blind apertures is enhanced by a combination of fluid jet sparging and cathode agitation. Excess conductor material in the resulting solder deposit can be avoided by replacing conductor material with a constituent component of a solder material in an immersion bath prior to electroplating.

Process for selective application of solder to circuit packages

Electroplating apparatus

Printed circuit board or card for direct chip attachment and fabrication

Process is described for applying large quantities of solder to small areas, such as the lands in a high density card, to which it is intended to surface mount electronic devices or directly attach circuitized chips. The land area is temporarily extended by depositing a relatively thin layer of metal beyond the perimeter of the land, wave soldering to deposit excess solder on the extended land region, and reflow, whereby the thin layer of metal dissolves into the solder, causing the solder to retract to the dimensions of the original land. Because the volume of solder is increased, the strength and reliability of the solder joint is greatly improved.

Applying solder to high density substrates

The effectiveness of a palladium-tin catalyst for subsequent plating thereon is determined by employing cyclic voltammetry.

Process for determining the activity of a palladium-tin catalyst

Growing community of inventors

Apalachin, NY, United States of America

Richard Stuart Zarr