Functional fabrication of MEMS by ion implantation

Abstract

An ion-implantation material-modification technique was applied to a micro-electro mechanical systems (MEMS) fabrication technique in order to enhance the functionality of MEMS. Ion implantation, which is well known as doping technology in semiconductor and surface modification technology, can alter the characteristics of a substrate by the addition of ions. However, when the object is a microscale device such as MEMS, such implantation involves metallurgy of the micro material, because size, depth, and area of the modified area are on the same order as the size of the microscale device. When the characteristics that can be controlled by ion implantation are combined with other properties, such mechanical, electrical, optical, and chemical, a wide range of characteristics can be easily controlled simply by changing the operating parameters, such as ion species, energy, dose, and substrate temperature. By effectively utilizing region selectivity, which is an advantage of ion implantation, the local physical properties of a micro device can be controlled. Consequently, in the design of MEMS devices, material properties can be controlled to enhance the functionality of the device. In this study, we used this ion implantation technique, which only involved injection of ions and etching that changed the chemical property of the substrate material, to fabricate a micro device, e.g., a microcantilever beam, that has low elasticity and electric conductance.