Resonant-based test method for MEMS devices

Abstract

In this paper a test method for capacitive Micro-Electro-Mechanical Systems (MEMS) is presented. The proposed method utilizes the principle of resonant circuits to detect structural defects of capacitive MEMS devices. It is shown that a small variation of MEMS capacitance due to a defect alters the resonance frequency considerably. It is also shown that the variation of the output amplitude can be observed for fault detection if an inductor with a high quality factor is employed in the test circuit. Simulation results using an implemented MEMS comb-drive indicate that the proposed method can detect common faults such as missing, broken and short fingers.

A ΣΔ Closed-Loop Interface for a MEMS Accelerometer with Digital Built-In Self-Test Function

“…Besides waiting for the evolution of MEMS process, the in situ self-test and self-calibration will provide a promising new point of view on these problems [ 13 ] and, thus, attract extensive research attention worldwide [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. Although use of built-in self-test (BIST) units has been a routine technique in most mixed-signal system-on-chip (SoC) design flows [ 14 , 15 ], obstacles are encountered when implanting to an EM-ΣΔ system.…”

“…Direct implementation of electrostatic stimulus is only valid in a basic functional test, which aims to diagnose the defective dies in functional test or malfunction in practical usage. Many researchers have proposed diverse functional BIST methods, by incorporating the MEMS structure into a phase-lock loop (PLL) [ 16 ], resonator [ 17 ], or charge-pump [ 18 ] circuit, then, the working state of the circuit will be an indicator of malfunction. A more precise functional BIST is static symmetry testing, which can identify the location of defects by applying an electrostatic force on symmetrically distributed testing electrodes, and observing the output response [ 19 ].…”