The Royal Institution for the Advancement of Learning / Mcgill University

Transfert Plus, Societe En Commandite

Mems Vision International Inc.

Mohannad Elsayed

Frederic Nabki

Mourad El-Gamal

Paul-Vahe Cicek

Fréderic Nabki

Michaël Ménard

Optical spectroscopy is a widely used method to identify the chemical composition of materials and the characteristics of optical signals. Silicon based integrated photonics offers a platform for many optical functions through microelectromechanical systems (MEMS) and microoptoelectromechanical systems (MOEMS), silicon waveguides, integrated CMOS electronics and hybrid integration of compound semiconductor elements for optical gain. Accordingly, it would be beneficial to provide advanced optical tools for techniques such as optical spectroscopy and optical tomography exploiting MOEMS to provide swept filters that offer improved performance, increased integration, reduced footprint, reduced power consumption, increased flexibility, reconfigurability, and lower cost. Further, such MOEMS elements can support the provisioning of swept optical sources, swept filters, swept receivers etc. in the planar waveguide domain without free space optics.

Micro-motor based swept wavelength optical components

Micromachined microelectromechanical systems (MEMS) based resonators offer integration with other MEMS devices and electronics. Whilst piezoelectric film bulk acoustic resonators (FBAR) generally exhibit high electromechanical transduction efficiencies and low signal transmission losses they also suffer from low quality factors and limited resonance frequencies. In contrast electrostatic FBARs can yield high quality factors and resonance frequencies but suffer from increased fabrication complexity. lower electromechanical transduction efficiency and significant signal transmission loss. Accordingly, it would be beneficial to overcome these limitations by reducing fabrication complexity via a single metal electrode layer topping the resonator structure and supporting relatively low complexity/low resolution commercial MEMS fabrication processes by removing the fabrication requirement for narrow transduction gaps. Beneficially, embodiments of the invention provide MEMS circuits with electrostatic tuning and provide resonator designs combining the advantages of piezoelectric actuation and bulk-mode resonators.

Bulk mode microelectromechanical resonator devices and methods

Considerations for selecting capacitive sensors include accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, integration options with other sensors and/or electronics, and cost effectiveness. It is beneficial if such sensors are amenable to above-IC integration with associated control/readout circuitry for reduced parasitics and reduced footprint through area sharing. The inventors have established a combined Lorentz force based magnetometer and accelerometer MEMS sensor exploiting a low temperature, above-IC-compatible fabrication process operating without requiring vacuum packaging. By switching an electrical current between two perpendicular directions on the device structure a 2D in-plane magnetic field measurement can be achieved while concurrently, the device serves as a 1D accelerometer for out-of-plane acceleration, by switching the current off and by monitoring the structure's capacitive change in response to acceleration. The design can thus separate magnetic and inertial force measurements, utilizing a single compact device.

Combined magnetometer accelerometer MEMS devices and methods

Micromachined gyroscopes, such as those based upon microelectromechanical systems (MEMS) have the potential to dominate the rate-sensor market mainly due to their small size, low power and low cost. As MEMS gyroscopes are resonant devices requiring active excitation it would be beneficial to improve the resonator Q-factor reducing the electrical drive power requirements for the excitation circuitry. Further, many prior art MEMS gyroscope designs have multiple resonances arising from design and manufacturing considerations which require additional frequency tuning and control circuitry together with the excitation/sense circuitry. It would therefore be beneficial to enhance the bandwidth of the resonators to remove the requirement for such circuitry. Further, to address the relatively large dimensions of MEMS gyroscopes it would be beneficial for the MEMS gyroscopes to be fabricated directly above the CMOS electronics thereby reducing the die dimensions and lowering per die cost.

Growing community of inventors

Verdun, Canada

Mohannad Elsayed