Browse Prior Art Database

Hexagonal Grid Array Module with Hexagonal Grid Pattern

IP.com Disclosure Number: IPCOM000108009D
Original Publication Date: 1992-Apr-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 3 page(s) / 116K

Publishing Venue

IBM

Related People

Vanderlee, KA: AUTHOR

Abstract

Disclosed is a hexagonal grid array module. The module is an electronic component which has its interconnection pins, solder balls or other connection points on a hexagonal grid pattern. It also has on overall hexagonal shape. This invention allows an increased number of connection points (compared to currently available technology) within a given distance from the centroid of the component for a given spacing between connection points. That is, this design has greater interconnection density for a given pin-to-pin spacing than existing technology. (Image Omitted)

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Hexagonal Grid Array Module with Hexagonal Grid Pattern

       Disclosed is a hexagonal grid array module.  The module
is an electronic component which has its interconnection pins, solder
balls or other connection points on a hexagonal grid pattern.  It
also has on overall hexagonal shape.  This invention allows an
increased number of connection points (compared to currently
available technology) within a given distance from the centroid of
the component for a given spacing between connection points.  That
is, this design has greater interconnection density for a given
pin-to-pin spacing than existing technology.

                            (Image Omitted)

      Grid array modules are a type of electronic component commonly
used in the electronic card assembly industry.  The connection points
can be pins, leads, solder balls, bumps or columns of other
conductive materials.  The overall size of such a component is
usually limited by the fact that the connections at the connection
points (e.g., solder joints) are exposed to cyclic stresses during
the normal operation of the electronic card.  These stresses are
caused by the different thermal expansion coefficients of the module
substrate and the circuit card and the varying temperatures of the
module and card.  These stresses increase as the distance from the
centroid of the area array pattern increases, and the farther a
connection point is located from the centroid of the area array, the
sooner it will fail in fatigue.  Thus, for a given set of temperature
conditions and a given required life, there is a maximum allowable
distance between the centroid of the area array and the most distant
connection point.

      In the design of electronic circuit cards and components, it is
generally recognized that the cost and performance of the assembly
can be improved by increasing the number of connection points that
can be accommodated on an electronic component.  The reasons for this
are common knowledge in the electronics industry.  Thus, it is a
design objective to build components with greater numbers of
connection points.

      The final significant constraint to the design of grid array
modules is the minimum allowable spacing between connection points.
This is determined by the type of component, th...