Publications

While existing work in neural interfaces is largely geared toward the restoration of lost function in amputees or victims of neurological injuries, similar technology may also facilitate augmentation of healthy subjects. One example is the potential to learn a new, unnatural sense through a neural interface. The use of neural interfaces in healthy subjects would require an even greater level of safety and convenience than in disabled subjects, including reliable, robust bidirectional implants with highly-portable components outside the skin. We present our progress to date in the development of a bidirectional neural interface system intended for completely untethered use. The system consists of a wireless stimulating and recording peripheral nerve implant powered by a rechargeable battery, and a wearable package that communicates wirelessly both with the implant and with a computer or a network of independent sensor nodes. Once validated, such a system could permit the exploration of increasingly realistic use of neural interfaces both for restoration and for augmentation. © 2007 IEEE.

Low Temperature Cofired Ceramic (LTCC) has proven to be an enabling medium for microsystem technologies, because of its desirable electrical, physical, and chemical properties coupled with its capability for rapid prototyping and scalable manufacturing of components. LTCC is viewed as an extension of hybrid microcircuits, and in that function it enables development, testing, and deployment of silicon microsystems. However, its versatility has allowed it to succeed as a microsystem medium in its own right, with applications in non-microelectronic meso-scale devices and in a range of sensor devices. Applications include silicon microfluidic ''chip-and-wire'' systems and fluid grid array (FGA)/microfluidic multichip modules using embedded channels in LTCC, and cofired electro-mechanical systems with moving parts. Both the microfluidic and mechanical system applications are enabled by sacrificial volume materials (SVM), which serve to create and maintain cavities and separation gaps during the lamination and cofiring process. SVMs consisting of thermally fugitive or partially inert materials are easily incorporated. Recognizing the premium on devices that are cofired rather than assembled, we report on functional-as-released and functional-as-fired moving parts. Additional applications for cofired transparent windows, some as small as an optical fiber, are also described. The applications described help pave the way for widespread application of LTCC to biomedical, control, analysis, characterization, and radio frequency (RF) functions for macro-meso-microsystems.