Abstract
Micro-Electro-Mechanical Systems (MEMS) technologies have miniaturized numerous types of physical sensors, e.g., pressure, acceleration, and flow sensors, onto silicon wafers. Along with their capabilities of miniaturizing mechanical components to a size of less than a few millimeters, MEMS technologies have also been introduced to the fabrication of micro-needles for the evaluation of the nerve systems. These micro-needles also have been used as trans-dermal drug delivery systems since the late 1990s. In this article, the outline of the MEMS fabrication is summarized, and then various type micro-needles, Si-, metal-, and polymer-needles, developed by MEMS are reviewed. The micro-needle produced by a biodegradable material is finally stated as an example the most expecting technology for the trans-dermal drug delivery systems.
