Probing heavy ion radiation effects in silicon carbide (SiC) via 3D integrated multimode vibrating diaphragms.

We report on the measurement and analysis of energetic heavy ion radiation effects on the mechanical properties of silicon carbide (SiC) crystals, by exploiting a vertical stack of micromachined vibrating SiC thin diaphragms integrated in a three-dimensional (3D) fashion. The diaphragms are 1 mm × 1 mm in lateral dimensions and 2 μm in thickness, vibrating at their multiple flexural modes in the range of 200 to 800 kHz. Upon 10.25 MeV oxygen ion irradiation, the 4 devices in the 3D stack exhibit saliently different changes in their multimode resonance frequencies. The device that is intended to capture most ions shows the largest frequency downshifts (∼6.6%–11.3%), corresponding to the extracted tension release from 382 MPa to 306 MPa, which can be explained by the maximum displacement damage in this device. The design of 3D integration not only scientifically enables probing different radiation effects in multiple devices simultaneously with clear controls but also economically evades very expensive, repetitive tests on individual devices, thus proving to be a powerful platform for analyzing and understanding radiation damage in micro/nanoelectromechanical systems and other micro/nanosystems. [ABSTRACT FROM AUTHOR]