Tensile Strength of Single-Crystal Silicon under High Strain Rates

Single-crystal silicon (SCS) is a pivotal substrate material for silicon-based MEMS (micro-electromechanical systems), playing an indispensable role in the modern integrated circuit and semiconductor industries due to its advantages in miniaturization and high-level integration. Despite its widespread use, a significant knowledge gap exists regarding its dynamic mechanical behavior, particularly its tensile properties under high strain-rate loading. This deficiency critically limits the reliability and design envelope of devices operating under dynamic conditions such as impact and vibration. Addressing the common risk of tensile failure in MEMS devices during service, this study systematically investigates the dynamic tensile response of SCS using a Split Hopkinson Tension Bar (SHTB) system. Concurrently, a full-scale finite element model of the SHTB apparatus was developed to numerically simulate the material’s dynamic response. The experimental results reveal that SCS exhibits pronounced strain-rate sensitivity, with its dynamic tensile strength increasing markedly as the strain rate rises. The stress-strain curves and failure modes obtained from the numerical simulations demonstrate excellent agreement with the experimental data, thereby validating the accuracy and efficacy of the developed model. This research not only elucidates the high strain-rate tensile mechanics of SCS but also provides a crucial reference for the dynamic structural design, performance prediction, and optimization of silicon-based MEMS devices.