Fabrication of Microbridges Using Oxidized Porous Silicon

Abstract

A new fabrication process of micromachines using oxidized porous silicon film has been developed. The porous silicon film with thickness of several micrometers was made from p-type silicon by anodization in 46% HF solution and at a constant current density of 30mA/cm². The porous silicon was thermally oxidized at 1, 100°C for 30 min. in dry O₂ gas. Two types of microbridges were fabricated by using oxidized porous silicon as a sacrificial layer. It is shown that thick oxide layer can be selectively formed by using the porous silicon.