@cti.gov.br
Assembly, Electronic Packaging and Systems Division
Centro de Tecnologia da Informação Renato Archer
Electrical and Electronic Engineering, Electronic, Optical and Magnetic Materials, Renewable Energy, Sustainability and the Environment, Engineering
Scopus Publications
Ricardo Cotrin Teixeira, Alexander Flacker, Giuliano Maiolini, Rodrigo Reigota Cesar, Guilherme Cartagena Miron, and Julio Apolinario Cordioli
IEEE
The use of implantable devices for biomedical applications has been made possible by the ubiquity of vibration sensors and accelerometers, coupled with advances in microfabrication technologies. Among these devices, implantable auditory prostheses, such as hearing aids and cochlear implants, have emerged as a viable alternative to traditional external devices, which can cause discomfort to users. To meet the requirements for implantable auditory devices, a piezoelectric microelectromechanical systems (MEMS) accelerometer has been developed, which includes an AlN (Aluminun Nitrate) piezoelectric signal generator attached to a silicon proof mass. This paper presents the fabrication route developed at the Assembly, Packaging and System Integration Division from Renato Archer Center for Information Technology (DIMES/CTI), including anisotropic etching of silicon cavities, flip chip assembly and signal extraction routes, to seal a silicon proof mass sample (accelerometer) fabricated by a third party.
Eliana Gomes, Giuliano Maiolini, and Felipe Rudge Barbosa
The Electrochemical Society
We have developed and successfully obtained stable and reliable processes in our labs for metallization and pad definition of passivated Si substrates for microelectronic flip-chip assembly with solder bumps, applicable to high-density interconnection technology. Patterned samples were prepared with aluminum pads on Si/SiO2 over which the UBM multilayer metals were deposited. Pads are 90x90micron^2 with 185micron pitch. All metal layers show good stability and adherence, and the final processes have good reproducibility and stability. A flip-chip assembly using solder micro-bumps deposited over the pads was used to demonstrate stability and reliability of the process. This set of processes - metallization, pad definition and flip-chip assembly - will next be applied to functional devices.