Abstract:
A multi-material resonant thin film beam for a micromechanical sensor having a zero temperature coefficient of frequency (TCF) which is the resonant frequency shift with temperature change. One of the materials may be polysilicon and the other material may be silicon nitride or silicon oxide. Each material has a different thermal coefficient of expansion. The proportion of the various materials is adjusted and the specific geometries are determined so that the TCF is zero. One embodiment is a microbeam composed of two polysilicon thin films with a silicon nitride thin film inserted between the polysilicon films. The thickness of the silicon nitride film may be adjusted to trim the TCF to zero. The film of nitride instead may be placed on one side of a polysilicon film to form a beam. Dual or multiple beam resonators likewise may be made with several materials. The nitride may be placed in the shank areas which join and secure the ends of the beams. Such zero TCF beams may be incorporated in microsensor structures for measuring pressure, temperature, strain and other parameters.
Abstract:
Structure microélectronique comportant une masse mobile (2) reliée mécaniquement à premier (12) et un deuxième (24) élément mécanique par des premiers (6) et deuxièmes (14) moyens de liaison mécanique respectivement, une source de polarisation (15) des deuxièmes moyens de liaison mécanique (14). Les deuxièmes moyens de liaison mécanique (14) comportent deux éléments de liaison (18, 20) et un réservoir thermique (22) interposé entre les éléments de liaison (18, 20), au moins l'un des éléments de liaison étant en un matériau piézorésistif, au moins l'un des premier et deuxième éléments de liaison présentant des propriétés de thermoélasticité. Le réservoir thermique (22) présentant une capacité thermique différente de celles des éléments de liaison (18, 20). Les deuxièmes moyens de liaison (14) et la masse mobiles (2) sont disposés l'un par rapport à l'autre de sorte qu'un déplacement de la masse mobile (2) applique une contrainte mécanique aux deuxièmes moyens de liaison (14).
Abstract:
A multiple coil spring MEMS resonator includes a center anchor and a resonator body including two or more coil springs extending in a spiral pattern from the center anchor to an outer closed ring. Each pair of coil springs originates from opposing points on the center anchor and extends in the spiral pattern to opposing points on the outer ring. The number of coil springs, the length and the width of the coil springs and the weight of the outer ring are selected to realize a desired resonant frequency.
Abstract:
The invention relates to an inertial sensor comprising a frame to which at least two seismic bodies are connected by resilient means such as to be movable in a suspension plane, and transducers to keep the seismic bodies vibrating and determine a relative movement of the seismic bodies relative to one another, characterized in that the seismic bodies have a single shape and a single mass, and in that the seismic bodies comprise interlocking parts such that the seismic bodies are nested inside one another while being movable in the suspension plane relative to the other of the seismic bodies, the seismic bodies having centres of gravity that coincide with one another. The invention also relates to a method for manufacturing such a sensor.
Abstract:
The invention relates to a device comprising a base substrate(700) with a micro component (702) attached thereto. Suitably it is provided with routing elements (704) for conducting signals to and from said component (702). It also comprises spacer members (706) which also can act as conducting structures for routing signals vertically. There is a capping structure (708) of a glass material, provided above the base substrate (700), bonded via said spacer members (706), preferably by eutectic bonding, wherein the capping structure (708) comprises vias (710) comprising metal for providing electrical connection through said capping structure. The vias can be made by a stamping/pressing method entailing pressing needles under heating to soften the glass and applying pressure, to a predetermined depth in the glass. However, other methods are possible, e-g- drilling, etching, blasting.