Abnormal grain growth in 0.75-μm-thick aluminum alloy thin films has been studied using x-ray diffractometry, plan-view and cross-sectional transmission electron microscopy, scanning transmission electron microscopy, and energy dispersive x-ray analysis. Transmission electron microscopy was used with preannealed samples as well as with samples annealed in situ. By varying the deposition temperatures, compositions, and annealing conditions, we have determined the roles of alloying elements in the formation of second-phase precipitates and in promoting abnormal grain growth.

No abstract

In 2001, IBM delivered to the marketplace a high-performance UNIX ® -class eServer based on a four-chip multichip module (MCM) code named Regatta. This MCM supports four POWER4 chips, each with 170 million transistors, which utilize the IBM advanced copper back-end interconnect technology. Each chip is attached to the MCM through 7018 flip-chip solder connections. The MCM, fabricated using the IBM high-performance glass-ceramic technology, features 1.7 million internal copper vias and high-density topsurface contact pad arrays with 100-m pads on 200-m centers. Interconnections between chips on the MCM and interconnections to the board for power distribution and MCM-to-MCM communication are provided by 190 meters of co-sintered copper wiring. Additionally, the 5100 off-module connections on the bottom side of the MCM are fabricated at a 1-mm pitch and connected to the board through the use of a novel land grid array technology, thus enabling a compact 85-mm ؋ 85-mm module footprint that enables 8-to 32-way systems with processors operating at 1.1 GHz or 1.3 GHz. The MCM also incorporates advanced thermal solutions that enable 156 W of cooling per chip. This paper presents a detailed overview of the fabrication, assembly, testing, and reliability qualification of this advanced MCM technology.

We report a new experimental technique for the study of electromigration in Al lines containing controlled, single, identical grain boundaries with boundary planes perpendicular to the plane of the substrates. We show that failure times of these lines are lognormally distributed; that the median time to failure depends more strongly on the boundary orientations than the types of grain boundaries; that the deviation in the time to failure has a large component not dependent on microstructure; and that both interfacial diffusion and grain boundary diffusion appear to contribute to failure in bicrystal lines, and likely in bamboo and near-bamboo lines.

Wehave developed a new experimental technique to study electromigration in bicrytal Al lines as a function of the type and location of the grain boundary as well as the testing temperature.The failure times of these lines are found to be lognormally distributed.The median time to failure (MTTF) depends more strongly on the boundary orientation than the type of grain boundary.The dependence of lifetimes on the type and orientation of grain boundaries, the location and appearance of the failure sites, and the measured activation energy (E.) of 0.94eV suggest that both interfacial and grain boundary diffusion contribute to failure in bicrystal lines, and likely in bamboo and near-bamboo lines as well.