Ultra-smooth e-beam evaporated amorphous silicon thin films - A viable alternative for PECVD amorphous silicon thin films for MEMS applications

In this paper, we demonstrate the applicability of ultra-smooth e-beam evaporated amorphous silicon thin films (<500 nm) as an alternative for PECVD thin films in MEMS applications. In this regard, a thorough investigation of the material and structural characteristics of low-temperature e-beam evaporated amorphous silicon thin films is carried out and it reveals that these properties are very similar to that of PECVD silicon thin films. E-beam evaporated amorphous silicon offers an ultra-smooth surface, which helps in realizing MEMS devices with close to ideal frequency response. The suitability of these thin films for MEMS applications is demonstrated by fabricating micro-cantilevers using the optimized thin film deposition conditions. (C) 2017 Elsevier B.V. All rights reserved.