XYZ on a Chip: Development and Fabrication of Three-Dimensional Microdevices

Boston College, Chestnut Hill MA

Investigators

Abstract

The use of silicon-based technology, originally developed for microelectronics applica-tions, in the fabrication of microelectromechanical and microfluidic structures has ushered in a new era in which complex tasks can be performed by efficient, miniaturized devices. However, one limitation of the current generation of silicon-based technologies is that it is extraordinarily difficult to fabricate devices have a significant number (>4) of functional layers. The number of potential applications of microdevices would expand geometrically if it were possible to fabricate microdevices that were not constricted by the present layer-by- layer fabrication scheme, but instead were truly three-dimensional. We are proposing to develop and utilize a completely new set of technologies for non-silicon-based microfabrication of true three-dimensional devices. Our scheme takes ad-vantage of multiphoton absorption (MPA) interactions that occur selectively at the tight fo-cus of a laser beam to attain high three-dimensional resolution. The proposed technology begins with a nanoporous matrix that is solidified and etched selectively in different spatial areas, based on MPA, in order to create the three-dimensional template for a microdevice. Localized MPA-driven photodeposition and other MPA-driven photoreactions, photo-chemical processes and photophysical processes are then used to create functional compo-nents within the matrix, with submicron feature sizes. Through these means, it will be pos-sible to incorporate a wide variety of functionalities in a single, monolithic three-dimensional device. Over the proposed three-year project period, we will develop MPA-based technologies to make a broad range of functional fluidic, electronic, optical and mechanical components. These components will be combined to fabricate increasingly complex three-dimensional microdevices that will allow for the miniaturization of technologically important tasks in areas such as combinatorial synthesis and screening of drug candidates and low-temperature device physics. By the end of the project period we expect to be able to inte-grate such devices directly onto silicon-based microchips.