Polymeric Materials Requirements for the GE High-Density Interconnect Process

Abstract

In the GE High-Density Interconnect Process, thermoplastic polyetherimide adhesives with selectively variable glass transition temperatures (Tg's) are used as chip attach and overlay adhesive. Alternating layers of patterned metal and dielectric are then applied to fabricate the interconnect structure. Upper layer dielectrics are formed using a modified siloxane-polyimide that can be processed at temperatures below 200 °C. The unique materials requirements and materials development issues associated with this approach are discussed.

The multilayer-modified Stoney’s formula for laminated polymer composites on a silicon substrate

“…Also, the maximum substrate bow value at room temperature after fabrication and storage for 48 h increased to about 210 m because of the increased amount of Ultem thermoplastic. Table IV summarizes For more realistic modeling of the lamination-based MCM-D substrates, where the fabrication of upper-layer dielectrics must be accomplished at the temperatures below the temperatures of low-layer dielectrics, 13 the Ultem/Kapton composite and Coverlay film were laminated sequentially on a silicon substrate at 310 and 150°C, respectively. Figure 9 shows the thermal behavior of such a multilayer structure, a silicon/Ultem/Kapton/epoxy/Kapton ͑Si/U50KH25/ E25KH25͒ structure, where the 50.8 m Ultem thermoplastic and the 25.4 m epoxy thermoset were used as lamination adhesives, and the 25.4 m Kapton films were used as overlay films.…”

“…1. 12,13 In the lamination process, a polymeric overlay film is overlaid on a silicon substrate using a polymeric adhesive, so the process involves at least doublelayered composite films consisting of the overlay film and adhesive. When it comes to the thermal behavior of metal thin film interconnections not only on silicon wafers [7][8][9][10][11] but also on multilayer substrates, a correct understanding of the thermal behavior of the multilayer substrates themselves is a necessary first step.…”

A quantitative analysis of the stress relaxation effect of thermoplastics in multilayer substrates

“…While many attractive properties of the materials, such as easy-to-process property, reworkability, and stress relaxation effect, have been obvious [2], because of the relatively poor Manuscript received August 27, 1997; revised July 30, 1999. J. S. Kim mechanical properties at high temperatures, the use of the thermoplastics has for a long time been limited in microelectronics applications; where electronic polymers are typically exposed to fluctuating, and often extreme thermal histories.…”