Study of Ni Metallization in Macroporous Si Using Wet Chemistry for Radio Frequency Cross-Talk Isolation in Mixed Signal Integrated Circuits.

A highly conductive moat or Faraday cage of through-the-wafer thickness in Si substrate was proposed to be effective in shielding electromagnetic interference thereby reducing radio frequency (RF) cross-talk in high performance mixed signal integrated circuits. Such a structure was realized by metallization of selected ultra-high-aspect-ratio macroporous regions that were electrochemically etched in p- Si substrates. The metallization process was conducted by means of wet chemistry in an alkaline aqueous solution containing Ni2+ without reducing agent. It is found that at elevated temperature during immersion, Ni2+ was rapidly reduced and deposited into macroporous Si and a conformal metallization of the macropore sidewalls was obtained in a way that the entire porous Si framework was converted to Ni. A conductive moat was as a result incorporated into p- Si substrate. The experimentally measured reduction of crosstalk in this structure is 5~18 dB at frequencies up to 35 GHz

In-situ study of electromigration-induced grain rotation in Pb-free solder joint by synchrotron microdiffraction

The rotation of Sn grains in Pb-free flip chip solder joints hasn't been reported in literature so far although it has been observed in Sn strips. In this letter, we report the detailed study of the grain orientation evolution induced by electromigration by synchrotron based white beam X-ray microdiffraction. It is found that the grains in solder joint rotate more slowly than in Sn strip even under higher current density. On the other hand, based on our estimation, the reorientation of the grains in solder joints also results in the reduction of electric resistivity, similar to the case of Sn strip. We will also discuss the reason why the electric resistance decreases much more in strips than in the Sn-based solders, and the different driving force for the grain growth in solder joint and in thin film interconnect lines

In situ measurement of electromigration-induced transient stress in Pb-free Sn-Cu solder joints by synchrotron radiation based X-ray polychromatic microdiffraction

Electromigration-induced hydrostatic elastic stress in Pb-free SnCu solder joints was studied by in situ synchrotron X-ray white beam microdiffraction. The elastic stresses in two different grains with similar crystallographic orientation, one located at the anode end and the other at the cathode end, were analyzed based on the elastic anisotropy of the {beta}-Sn crystal structure. The stress in the grain at the cathode end remained constant except for temperature fluctuations, while the compressive stress in the grain at the anode end was built-up as a function of time during electromigration until a steady state was reached. The measured compressive stress gradient between the cathode and the anode is much larger than what is needed to initiate Sn whisker growth. The effective charge number of {beta}-Sn derived from the electromigration data is in good agreement with the calculated value

Plastic deformation in Al (Cu) interconnects stressed by electromigration and studied by synchrotron polychromatic X-ray microdiffraction

We report here an in-depth synchrotron radiation based white beam X-ray microdiffraction study of plasticity in individual grains of an Al (Cu) interconnect during the early stage of electromigration. The study shows a rearrangement of the geometrically necessary dislocations (GND) in bamboo typed grains during that stage. We find that about 90percent of the GNDs are oriented so that their line direction is the closest to the current flow direction. In non-bamboo typed grains, the Laue peak positions shift, indicating that the grains rotate. An analysis in terms of force directions has been carried out and is consistent with observed electromigration induced grain rotation and bending

Kinetic Phenomena in Thin Film Electronic Materials

Contains reports on ten research projects.Semiconductor Research Corporation (Grant 83-01-033)National Science Foundation (Grant DMR 81-19285)U.S. Department of Energy (Contract DE-ACO2-82-ER-13019)National Science Foundation (Grant ECS82-05701)International Business Machines, Inc.Dartmouth UniversityJoint Services Electronics Program (Contract DAAG29-83-K-0003

Microstructural Evolution in Thin Films of Electronic Materials

Contains reports on eight research projects and a list of publications.National Science FoundationU.S. Air Force - Office of Scientific ResearchJoint Services Electronics Program Contract DAAL03-89-C-0001IBM CorporationHitachi CorporationSemiconductor Research CorporationNational Institutes of Healt

Kinetic Phenomena in Thin Film Electronic Materials

Contains reports on nine research projects.National Science Foundation (Grant ECS85-06565)Semiconductor Research CorporationU.S. Air Force - Office of Scientific Research (Grant AFOSR-85-0154)National Science Foundation (Grant DMR81-19285)Sony International Business Machines, Inc.Dartmouth UniversityJoint Services Electronics Program (Contract DAAG29-83-K-0003)Semiconductor Research Corporatio

Kinetic Phenomena in Thin Film Electronic Materials

Contains reports on twelve research projects.National Science Foundation (Grant ECS 85-06505)U.S. Air Force - Office of Scientific Research (Contract AFOSR-85-0154)Semiconductor Research Corporation (Contract 87-SP-080)National Science Foundation (Grant ECS 85-06565)International Business Machines, Inc.Sony International Business Machines, Inc.National Science Foundation (Grant DMR 84-18718)International Business Machines, Thomas J. Watson Research CenterJoint Services Electronics Program (Contract DAALO3-86-K-0002)National Science Foundation (Grant DMR 85-06030)Charles Stark Draper Laboratory (Contract DL-H-261827)Nippon Telegraph and Telephone, Inc

Microstructural Evolution in Thin Films of Electronic Materials

Contains reports on ten research projects.Joint Services Electronics Program Contract DAAL03-89-C-0001National Science FoundationU.S. Air Force - Office of Scientific Research Contract AFOSR 85-0154Semiconductor Research CorporationAT&TInternational Business Machines CorporationNational Institutes of Healt

Microstructural Evolution in Thin Films of Electronic Materials

Contains reports on eight research projects.National Science Foundation (Grant ECS 85-06565)U.S. Air Force - Office of Scientific Research (Contract AFOSR 85-0154)National Science Foundation-Materials Research Laboratory(Grant DMR 81-19285)National Science Foundation (Grant DMR 85-06030)International Business Machines, Inc. Faculty Development AwardMitsui Career Development AwardInternational Business Machines, Inc.Semiconductor Research Corporation (Contract 86-05-080)Joint Services Electronics Program (Contract DAAG-29-83-K-0003)Charles Stark Draper LaboratoryDefense Advanced Research Projects Agency (DARPA)Nippon Telegraph and Telephone, Inc