Low-cost, high reliability flip-chip removal for multi-chip modules

Abstract

The prevalent trend to consolidate devices onto multi-chip modules due to electrical performance benefits and printed circuit board real-estate constraints drives the need to have a device replacement technology. The ability to remove and replacc devices, for either defective conditions or upgrade level designs, while preserving the electrical integrity and reliability of the other components on the module at various stages of manufacture is essential. It is not a cost-effective option to discard the remaining expensive die or to scrap the fully assembled complex module. The process must also be able to be exercised easily in a development environment where resources are at a minimum, but the learning generated through the ability to perform such operations in-situ is imperative. With the emergence of OEM assembly vendors, this technique and process must also be simple, inexpensive and easy to use, as a company should not be required to invest large resources in remove and replace manufacturing operations.

An advanced multichip module (MCM) for high-performance UNIX servers

“…The ICR process has evolved over time and has been described in detail elsewhere [14,15]. The three basic steps of ICR are individual chip removal, dressing of the TSM chip site with a sintered porous Cu block, and joining a new chip using the same furnace reflow process used for initial chip join ( Figure 9).…”