Property modification of 3C-SiC MEMS on Ge-modified Si(100) substrates

The manipulation of nucleation and growth conditions with Ge deposition prior to the carbonization and epitaxial growth changes the residual stress and the material quality of 3C-SiC(100)-layers grown on Si(100). This enables the modification of quality factor and resonant frequency of microelectromechanical systems (MEMS) based on 3C-SiC-layers. Measured resonant frequencies and quality factors of the magnetomotively actuated MEMS exhibit a dependence on the Ge amount at the interface of the Si/SiC heterostructure. This offers a degree of freedom to adjust the MEMS properties within a certain range to the requirements necessary for specific applications. The observed dependencies of the Young's modulus are in good agreement with the trends of residual stress and Young's modulus, which were determined on as grown 3C-SiC(100):Ge samples by fourier transform infrared (FTIR) spectroscopy and nanoindentation.