Browse Prior Art Database

Method for a solder preform as an interconnect for stacked MCMs

IP.com Disclosure Number: IPCOM000010577D
Publication Date: 2002-Dec-18
Document File: 3 page(s) / 107K

Publishing Venue

The IP.com Prior Art Database

Abstract

Disclosed is a method for a solder preform as an interconnect for stacked multichip modules (MCMs). Benefits include improved functionality, improved throughput, and improved ease of manufacturing.

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Method for a solder preform as an interconnect for stacked MCMs

Disclosed is a method for a solder preform as an interconnect for stacked multichip modules (MCMs). Benefits include improved functionality, improved throughput, and improved ease of manufacturing.

Background

        � � � � � Conventionally, MCMs are stacked using a paste print technology that is not cost efficient. MCMs are individually paste printed and then stacked onto another package (see Figure 1). The conventional solution uses an interposer (see Figure 2).

        � � � � � Solder preform is conventionally used in high-volume manufacturing packaging. Any shape can be manufactured through:

•        � � � � Alloying the solder

•        � � � � Stamping

•        � � � � Extruding

•        � � � � Compacting

•        � � � � Forming into the shape size and form required

General description

        � � � � � The disclosed method is a solder perform interconnection for stacking MCMs (see Figure 3).

� � � � � Solder preform laid onto a metal pad during the reflow process forms a solder interconnection through its high surface tension (see Figure 4). Solder preform over nonmetal is wicked into existing metal pads.

        � � � � � Package-to-package stacking on a wirebond utilizes two substrate packages with a solder perform pad and molding compound (see Figure 5).

        � � � � � Package-to-package stacking on a flip chip utilizes two substrate packages with a solder perform pad, solder bumps, and solder bump pads (see Figure 6).

        � � � � � The key elements of the method...