A Generic MEMS Fabrication Process Based on a Thermal Budget Approach

Abstract

A modular and generic monolithic integrated MEMS process for integrating CMOS technology with polysilicon microstructures is presented. The proposed process flow is designed with an intra CMOS approach to fabricate the microstructures into trenches without the need of planarization techniques. After annealing at 1000°C at significant period of time, it is shown that Id - Vg characteristics of the CMOS transistors remain almost unchanged, indicating their robustness to the intra process fabrication for the micromechanical structures. The CMOS module is designed with a 3 μm length as a minimum feature and this process results with a minimum of residual strain and stress on the micromechanical devices ( ε = 1.28 × 10 -4 and σ = -21 MPa).