Fracture of polycrystalline 3C-SiC films in microelectromechanical systems

Author

Gao, Di ; Carraro, Carlo ; Radmilovic, Velimir ; Howe, Roger T. ; Maboudian, Roya

Author_Institution

Dept. of Chem. Eng., Univ. of California, Berkeley, CA, USA

Volume

13

Issue

6

fYear

2004

Firstpage

972

Lastpage

976

Abstract

The fracture of polycrystalline SiC films is investigated using a micrometer-sized fracture tester fabricated by micromachining techniques. A series of SiC cantilever beams varying in length are carried by a moving shuttle tethered to the substrate, and are bent in plane until fracture. The fracture strain of SiC films is calculated from the deflection of bending beams using nonlinear beam theory and determined to be 3.3%±0.2%, which corresponds to a fracture stress of 23.4±1.4 GPa. These values are significantly higher than those for polycrystalline silicon. In addition, the crack propagation in the polycrystalline SiC films is observed to be transgranular.

Keywords

fracture; micromechanical devices; silicon compounds; thin films; wide band gap semiconductors; SiC; crack propagation; microelectromechanical systems; micromachining techniques; micrometer-sized fracture tester; nonlinear beam theory; polycrystalline 3C-SiC films; Acoustic beams; Capacitive sensors; Microelectromechanical systems; Micromachining; Micromechanical devices; Semiconductor films; Silicon carbide; Structural beams; Temperature sensors; Testing; 65; Fracture; MEMS; microelectromechanical systems; silicon carbide; thin films;

fLanguage

English

Journal_Title

Microelectromechanical Systems, Journal of

Publisher

ieee

ISSN

1057-7157

Type

jour

DOI

10.1109/JMEMS.2004.838372

Filename

1364056