Browse Prior Art Database

Areal Contacting of Chips to Modules

IP.com Disclosure Number: IPCOM000040032D
Original Publication Date: 1987-Sep-01
Included in the Prior Art Database: 2005-Feb-01
Document File: 2 page(s) / 57K

Publishing Venue

IBM

Related People

Behringer, U: AUTHOR [+6]

Abstract

Proposed is a system for high density areal contacting of chips to solder points on silicon modules. Generally, modules are electrically interconnected by solder reflow or wire bonding techniques. However, owing to the relatively large dimensions of the soldering points, these conventional techniques do not allow increasing the wiring densities on the module as would be desirable. According to this proposal, contacts to the soldering points are made by thin spiral or comb-shaped conducting silicon springs. The springs provide sufficient elasticity to tolerate the different thermal expansion of chips and modules. They are spring-loaded relative to the soldering points on the chip, thus permitting sequential point-by-point soldering of the connections.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 60% of the total text.

Page 1 of 2

Areal Contacting of Chips to Modules

Proposed is a system for high density areal contacting of chips to solder points on silicon modules. Generally, modules are electrically interconnected by solder reflow or wire bonding techniques. However, owing to the relatively large dimensions of the soldering points, these conventional techniques do not allow increasing the wiring densities on the module as would be desirable. According to this proposal, contacts to the soldering points are made by thin spiral or comb- shaped conducting silicon springs. The springs provide sufficient elasticity to tolerate the different thermal expansion of chips and modules. They are spring- loaded relative to the soldering points on the chip, thus permitting sequential point-by-point soldering of the connections. This feature affords easy chip connection and removal and is particularly suitable for field replacement. Rather than being limited to contact fingers on the periphery, contacts can be provided and reached throughout the entire chip surface, resulting in a dramatic increase of chip interconnections. The figures illustrate, rather schematically, preferred embodiments of the proposed areal chip contacting scheme, using spring contacts which interact with soldering points. Fig. 1 shows in greater detail a plan view and a sectional view of a wiring substrate 1, preferably of silicon, bearing electrically conductive interconnection lines 2 and providing spring contact areas
3. Spiral...