Nano-porous polysilicon fabrication for micro electro mechanical system (MEMS) drug delivery device

Abstract

Porous polysilicon is a biocompatible, non-toxic and biodegradable material, thus making it a suitable material to be implanted into human body as a drug delivery device. In this study, the method of stain etching in solution consists of HF, HNO3 and H2O in a ratio of 1:3:5 by volume has been used to create the nano-porous structures. The etching time was less than 30 seconds on a LPCVD polysilicon with sheet resistance of ~28 Ω/sq. The topography of the surface was then investigated by Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM). The resulting porous structure also exhibits a photoluminescence (PL) peak at around 700nm. The fabricated porous polysilicon is suitable as the material for an implantable drug delivery device, which offers significant advantages such as the ability to avoid dose dumping and providing patients with the required drug dosage over an extended period of time. © Springer-Verlag Berlin Heidelberg 2007.