Andrew C. McNeil

Design of Transducer and Package at the Same Time

The early effort of MEMS sensor development was focused mainly on the transducer: designing and manufacturing a mechanical device that could convert a physical input into an electrical signal using traditional semiconductor processes. With the rapid advancement in MEMS technologies, MEMS packaging is becoming increasingly critical and plays a major role in the successful commercialization of a MEMS product. Freescale has adopted the philosophy [1–2] of concurrent transducer and package designs to facilitate the rapid introduction of sensor products into the market. This paper presents a sub-modeling procedure that allows the modeling and simulation of a transducer and a package seamless at the same time.© 2005 ASME

Design evaluation of shock induced failure mechanisms of MEMS by correlation of numerical and experimental results

The paper presents a novel approach to evaluate and improve MEMS reliability even during design phase of new devices. Firstly, the shock induced failure mechanisms of breakage and stiction are characterized by test structures. The obtained results in terms of maximum rated loads are compared to acting loads during the actual mechanical shock, which are calculated by a numerical impact model. The model is based on the modal superposition approach and can be applied to arbitrary designs. It accounts for impacts at flexible travel stops including stiction as well as for large structural deflections leading to strongly nonlinear squeeze damping.

A new three axis low power MEMS gyroscope for consumer and industrial applications

The manuscript reports a new commercially available three axis gyroscope, the Freescale® FXAS21002C. The 6.8 mW power consumption is 20% less than the nearest competitors three axis device while meeting standard consumer device parameters. The three axis gyroscope has two proof masses and an open loop control scheme. The open loop architecture and the discontinuous control scheme contribute to this differentiated power consumption.

A static capacitance probe structure for resolving the sidewall skew angle of Silicon Deep Reactive-Ion Etching

This work presents a static capacitive probe structure that enables quantitative characterization of the effective sidewall skew angle of the Silicon Deep-Reactive-Ion-Etching (DRIE) using static LCR prober at ambient environment. The design is capable of resolving sidewall skew angles around both in-plane axes independently and simultaneously with the same sensitivity. The measured distributions of the sidewall skew angle across 8-inch wafers conform to empirical expectation and correlate tightly with quadrature error distributions measured gyroscopes from the same wafers. This work provides an easy, accurate and batch solution to the long existing challenge of resolving such process features in an industrial manufacturing environment.