Study on Designs of Stoppers for MEMS Devices in Shock Environment

Stoppers are commonly used to improve the shock resistance of MEMS devices. However, the collision between MEMS structure and stoppers in shock environment may lead to emergence of the stress wave, resulting in the failure of devices. Therefore, MEMS devices designed based on current statics theory is unreliable. After analyzing the method and principle for MEMS reliability design, the shock dynamics model was established. Based on the model, the response of the traditional design and designs with different stoppers to shock was researched. At last, protection performances of different stoppers were evaluated. Results showed that the use of stoppers could improve the shock resistance of the device obviously, but hard stoppers would cause to the emergence of the sharp stress wave. Elastic stoppers had excellent protection ability which could strengthen the shock resistance of the device greatly.