Dec 19 2005
A multilayer flexible substrate manufactured by 3M Electronics has been qualified for use in Staktek's new ArctiCore memory module and is now in production. The 3M brand, four-layer substrate helps double the memory density of a DIMM (Dual In-Line Memory Module). A high-density packaging solution is provided by the utilization of a flexible circuit that allows dense circuit routing and three-dimensional packaging.
In this server and workstation application, the multilayer flexible substrate from 3M is folded 180 degrees around ArctiCore's aluminum core, which cools the DIMM to provide superior thermal, mechanical and electrical performance than current rigid printed circuit board (PCB) technology. Wrapping the 3M substrate around the heat sink core enables assembly of memory devices to both sides of the circuit, resulting in higher data rates and better thermal conductivity than current PCB technology. Staktek uses the module in enterprise and consumer electronics applications.
The circuit's high wiring density is accomplished through fabrication of 30 micron trace and space widths, and 50 micron diameter blind, buried and through microvias. 3M maintains precision tolerances to achieve tightly controlled impedances and electrical timing, thus optimizing device performance.
The 3M substrates, ranging from two to six metal layers, are made using a variety of adhesiveless substrate materials and conventional or modified polyimide adhesives. Although the Staktek qualification is for an IC packaging application, 3M brand multilayer substrates also are used in medical, military/aerospace and other applications.