Mechanical characterization of polysilicon cantilevers using a thermo-mechanical test chip fabricated with a combined bulk/surface micromachining technique

Abstract

In this work a simplified low-frequency resonant method for the measurement of Young’s modulus of polysilicon cantilevers is described. We used a test chip, specially designed for characterizing thermal and mechanical properties, and fabricated using a combined bulk/surface micromachining process. In this regard, an opto-mechanical set up for the measurement of Young’s modulus is described. We use this set up for the characterization of 50 μm-wide, 1.0 μm-thick and 200–325 μm-long polysilicon cantilevers, under a mechanical excitation in the kHz frequency range.

Keywords

• Young’s modulus
• Polysilicon cantilevers
• Surface/bulk micromachining
• MEMS