Group III nitride and SiC based MEMS and NEMS: materials properties, technology and applications

TLDR

Wide band gap semiconductors such as SiC and group III nitrides are increasingly used in MEMS to satisfy demands for stability, miniaturization, and integration, offering new functionalities beyond traditional silicon micromachining. The paper reviews deposition and etching technologies for group III nitrides and SiC, focusing on fabricating three‑dimensional microstructures for MEMS. It outlines deposition and etching processes and explains the basic operation principle of wide band gap semiconductor MEMS, particularly for 3‑D microstructures. The study demonstrates initial SiC‑based MEMS applications and reviews innovative MEMS and NEMS devices.

Abstract

With the increasing requirements for microelectromechanical systems (MEMS) regarding stability, miniaturization and integration, novel materials such as wide band gap semiconductors are attracting more attention. Polycrystalline SiC has first been implemented into Si micromachining techniques, mainly as etch stop and protective layers. However, the outstanding properties of wide band gap semiconductors offer many more possibilities for the implementation of new functionalities. Now, a variety of technologies for SiC and group III nitrides exist to fabricate fully wide band gap semiconductor based MEMS. In this paper we first review the basic technology (deposition and etching) for group III nitrides and SiC with a special focus on the fabrication of three-dimensional microstructures relevant for MEMS. The basic operation principle for MEMS with wide band gap semiconductors is described. Finally, the first applications of SiC based MEMS are demonstrated, and innovative MEMS and NEMS devices are reviewed.