Proceedings Article | 16 August 2001
Proc. SPIE. 4334, Smart Structures and Materials 2001: Smart Electronics and MEMS
KEYWORDS: Mirrors, Microfluidics, Microsystems, Glasses, Interfaces, Silicon, Photography, Control systems, Transducers, Field effect transistors
The early '70s witnessed the introduction of the 'ion- selective field-effect transistor,' ISFET, which melded ion- selective electrode technology with standard microfabricated electronics and subsequently ushered in the era of integrated transducers. The futuristic allure of integrated transducers soon permeated the literature generating a literal zoo of unique sensors and actuators all purporting a litany of 'smaller, cheaper, better.' Capitalizing on the forte of microfabrication, the simple microdevice quickly evolved into arrays of microdevices and then on to integrated microsystems, complete with multiple transducers, actuators, and controls. However, the initial visions for integrated microsystems far outstripped available technical resources. For example, the simple ISFET required over twenty years to realize even limited commercialization. Process incompatibilities, materials issues, and fabrication limitations still present formidable challenges to any practical commercialization of most academic microsystem concepts. These limitations have generally mandated two strategic adaptations: (1) Limit products to simple, single-function/process microdevices such as in ink-jet printers, solid state pressure sensors, etc., or (2) Follow the example of high speed electronics and adopt a hybrid approach where the individual microdevices are individually fabricated and later assembled/packaged into the complex system. The latter approach is particularly apropos to optical microsystems which inherently demand a diverse range of nontraditional materials, photonic, and electro-optical components.
