GOALI: Chemical Design and Electrochemical Process Engineering for Micro-Fabrication

University Of New Hampshire, Durham NH

Investigators

Abstract

0930107 Barkey This GOALI proposal, to be carried out in partnership with Rohm and Haas Electronic Materials LLC, will advance the science and engineering of electrodeposition for fabrication of micro-devices and components including micro machines, passive electronic devices and electronic interconnects. The versatile chemistry of the acid-sulfate copper plating bath with additives makes it ideal for a broad class of micro-fabrication and electronics packaging applications. The work is based on the central role of interactions among additives, Cu(I) and dissolved oxygen. The local concentration of the latter two species can be controlled dynamically through such steps as pulse-reverse current to generate Cu(I) and gas diffusers to introduce oxygen. These ideas have been successfully implemented by the PI in filling of through-silicon vias. This work is intended to expand through-chip filling capabilities and to extend the process to encompass additional fabrication tasks, including the coating of interior recesses through restricted openings, and the filling of cavities in through-mask systems where the electrolyte is confined to a microscopic volume bounded by anode, substrate and mask. The work will encompass real fabrication processes on both bench and pilot scales as well as synthetic chemistry, electroanalytical studies and process modeling. This work will bring a comprehensive reaction-engineering perspective to the problem and advance beyond the conventional current-distribution understanding of simpler electroplating processes. Broader Impacts: This GOALI project will be carried out in partnership with Rohm and Haas Electronic Materials LLC through its facility in Freeport, NY. The research will enable advances in micro-fabrication and semi-conductor device manufacture with potential economic and societal benefits that include growth in the US high-tech manufacturing economy, new consumer products based on dense vertical semi-conductor packaging and advances in biomedical engineering based on micro-devices. In addition, the award will support the efforts of the UNH PI and Co-PI to engage undergraduate students in meaningful research projects. Continuing recruitment efforts by the PI include visits to area high schools and participation in the freshman environmental engineering lectures. The Chemical Engineering Department at UNH has been successful in recruiting and retaining women and underrepresented minorities in its program. In the past three years, the PI has supported four undergraduate researchers, including African-American and Vietnamese-American NH residents. The budget for the current project will include support for four undergraduate students per year, and the PI will make every effort to recruit students from under-represented groups into the project. The PI has served as a Mentor in the Ronald E. McNair Post-Baccalaureate Achievement Program, one of the TRIO Programs funded by Title IV of the Higher Education Act of 1965. The program is designed to encourage students from economically challenged and racially diverse backgrounds to consider and prepare for post graduate study and research. The PI intends to continue to serve in this program and to make his lab available for research projects by McNair Fellows.