International Business Machines Corporation

Jeffrey A Brody

Harry David Cox

John Joseph Garant

Hsichang Liu

Paul G McLaughlin

Dinesh Gupta

Tom Wayson

Wei Zou

John A Trumpetto

Hai Pham Longworth

Charles Timothy Ryan

Ahmed Sayeed Shah

Gerard John Nuzback

James C Monaco

Evelyn Barrington

Lorraine Di Piero-Simmonds

Edward J Hassdenteufel, Iii

Richard C Steger

Dale W Snowdon

An improved Land Grid Array interconnect structure is provided with the use of small metal bumps on the substrate electrical contact pad. The bumps interlock with segments of the fuzz button connection and increase the physical contact surface area between the contact pad and fuss button. The improved contact reduces displacement of electrical contact points due to thermo-mechanical stress and lowers the required actuation force during assembly.

Micro-bumps to enhance LGA interconnections

A screening mask having a stress-relieving area including an inner functional area having a pattern which is replicated on an underlying substrate, the inner functional area pattern having an one open area through which a paste is extruded and at least one tab, and an outer nonfunctional area distinct from the inner functional area, the outer nonfunctional area having a stress-relieving area adjacent to an edge of the screening mask that protects the at least one tab in the inner functional area from breaking.

Screening mask having a stress-relieving area

A screening mask for screening an article, the screening mask including a screening mask body having a screening side and a nonscreening side, an one opening through the mask for screening at least one feature from the screening side to the nonscreening side, and a blind opening for protecting a previously screened feature. The blind opening is blocked on the screening side and open on the nonscreening side. The screening mask is used in double pass screening so that a second feature may be formed on the article without damaging a previously formed feature.

Screening method for double pass screening

A method for minimizing formation of cracks at junctions between conductive vias and conductive lines in line-to-via connections on a substrate. The method comprises providing a transition zone connected between a base section of the line and a cap, the transition zone providing a volume of conductive paste during a conductive paste screen printing operation that is greater than the volume provided by the base section being directly connected to the cap. In particular, the transition zone volume is an effective amount to prevent necking of the conductive line into the via when the mask is misaligned to the substrate within an expected alignment tolerance. The transition zone may comprise a jogged end extending from the base section to the cap at an angle to the line, or a flared end extending from the base section. Line-to-via connection structures, patterns on a mask for making such structures, and masks having such patterns are also disclosed.

Method of forming conductive line features for enhanced reliability of multi-layer ceramic substrates

Conductive line features for enhanced reliability of multi-layer ceramic substrates

Growing community of inventors

Hopewell Junction, NY, United States of America

Jeffrey A Brody