Abstract: This invention comprises a process for fabricating a micro mechanical structure in a sealed cavity having a multi-layer high stiffness cap. The high stiffness material used for the cap protects the underlying microstructure from destructive environmental forces inherent in the packaging process and from environmental damage.
Abstract: This invention comprises a process for fabricating a MEMS microstructure in a sealed cavity wherein the etchant entry holes are created as a by-product of the fabrication process without an additional step to etch holes in the cap layer. The process involves extending the layers of sacrificial material past the horizontal boundaries of the cap layer. The cap layer is supported by pillars formed by a deposition in holes etched through the sacrificial layers, and the etchant entry holes are formed when the excess sacrificial material is etched away, leaving voids between the pillars supporting the cap.
December 13, 2002
Date of Patent:
December 26, 2006
IC Mechanics Inc.
L. Richard Carley, Suresh Santhanam, Hsu Yu-Nu
Abstract: The disclosed fabrication methodology addresses the problem of creating low-cost micro-electro-mechanical devices and systems, and, in particular, addresses the problem of delicate microstructures being damaged by the surface tension created as a wet etchant evaporates. This disclosure demonstrates a method for employing a dry plasma etch process to release encapsulated microelectromechanical components.
Abstract: This invention discloses a method for controlling the position of flexible portions of a mechanical structure by attaching one or more Momentum Transfer Actuators on the flexible portions of the mechanical structure near the points whose position is to be controlled, sensing the position of the flexible portions of the mechanical structure, and, employing one or more feedback loops, to control the Momentum Transfer Actuators to cause the flexible ends of the mechanical structure to follow a desired position as a function of time. The invention also addresses the use of combined actuating and sensing devices that incorporate both a Momentum Transfer Actuator and an inertial sensor to provide acceleration, velocity, and position information to the feedback control system.
Abstract: This invention discloses a method for facilitating the writing of sector servo marks on disk drives that makes use of an inertial sensor mounted on the positioning arm of the disk drive. In addition, this patent discloses several operating strategies that enhance the accuracy of the inertial sensor when it is used to write sector servo marks.
Abstract: This invention discloses a method for electronically decreasing the sensitivity of thin film movable micromachined layers to vibrations, accelerations, or rotations that would result in part or all of the movable layer being displaced in the direction of the film thickness. In addition, the disclosed method can also be used to remove some of the curvature introduced into thin film movable structures due to vertical stress gradients. Electronic stiffening is achieved by using position sensing and force feedback at one or more points on the movable micromachined structure. Precise servo control of Z axis height makes it possible to dramatically decrease the spacing between the movable MEMS layer or layers and fixed electrodes, which can lead to a dramatic increase in sensitivity and/or actuation force.