Motorola Corporation

Freescale Semiconductor,inc.

Gary J O'Brien

Andrew C McNeil

Mark D Summers

David Joseph Monk

Gary G Li

Gordon D Bitko

Ronald P Bieschke

Todd F Miller

A proof mass () for a MEMS device is provided herein. The proof mass comprises a base () comprising a semiconductor material, and at least one appendage () adjoined to said base by way of a stem (). The appendage () comprises a metal () or other such material that may be disposed on a semiconductor material (). The metal increases the total mass of the proof mass () as compared to a proof mass of similar dimensions made solely from semiconductor materials, without increasing the size of the proof mass. At the same time, the attachment of the appendage () by way of a stem () prevents stresses arising from CTE differentials in the appendage from being transmitted to the base, where they could contribute to temperature errors.

Method of adding mass to MEMS structures

A method for creating a MEMS structure is provided. In accordance with the method, a substrate () is provided having a sacrificial layer () disposed thereon and having a layer of silicon () disposed over the sacrificial layer. A first trench () is created which extends through the silica layer and the sacrificial layer and which separates the sacrificial layer into a first region () enclosed by the first trench and a second region () exterior to the first trench. A first material () is deposited into the first trench such that the first material fills the first trench to a depth at least equal to the thickness of the sacrificial layer. A second trench () is created exterior to the first trench which extends through at least the silicon layer and exposes at least a portion of the second region of the sacrificial layer. The second region of the sacrificial layer is contacted, by way of the second trench, with a chemical etching solution adapted to etch the sacrificial layer, said etching solution being selective to the first material.

SOI polysilicon trench refill perimeter oxide anchor scheme

An acceleration sensor includes a substrate ( ), a proof mass ( ) over the substrate and having first and second attachment regions ( ), and an anchor structure ( ) coupled to the substrate. The sensor additionally includes a first suspension beam ( ) coupling the anchor structure to the first attachment region to suspend the proof mass over the substrate. The sensor further includes a second suspension beam ( ) coupling the anchor structure to the second attachment region to suspend the proof mass over the substrate. The first suspension beam has a first radius ( ) extending from the anchor structure to the first attachment region, and the second suspension beam has a second radius ( ) extending from the anchor structure to the second attachment region where the first radius is greater than the second radius.

Acceleration sensor and method of manufacture

An apparatus and method is disclosed for a semiconductor wafer front side pressure testing system ( ). Negative or positive pressure is applied to the top portion of a semiconductor wafer ( ) mounted on a support structure or wafer chuck ( ). In one embodiment, bellows ( ) coupled to the wafer chuck ( ) and a platen ( ) located above the semiconductor wafer ( ) provides a sealed atmosphere above the semiconductor wafer ( ) to permit negative or positive pressure to be introduced into this sealed atmosphere. In another embodiment, a seal is provided by a wall portion ( ) connected to the chuck ( ) contacting a gasket ( ) located beneath the platen ( ).

Semiconductor wafer front side pressure testing system and method therefor

An actuator includes a support layer (,), a stationary structure (,) located over the support layer and including two portions (,) adjacent to each other and separated from each other by a gap (,), and a movable structure (,) coupled to and located over the support layer, located adjacent to the stationary structure, and movable relative to the stationary structure and the support layer. A portion (,) of the movable structure is located in the gap between the two portions of the stationary structure, and the portion of the movable structure comprises a body (,) and an asymmetric structure (,) extending from the body.

Actuator and method of manufacture

Heater circuits (13) are placed in close proximity or integrated with connection points (12) of an integrated circuit. A connection point is an area where a wire bond or conductive bump is coupled for providing electrical interconnection external to an integrated circuit. Heater circuits (13) are polysilicon strips that form resistive heat elements. A DC voltage or a pulsed voltage is applied to the heater circuits (13) to generate a local heat at the connection points that can reach temperatures exceed 1000 degrees centigrade. The heat is localized to an area near the connection point to prevent damage to temperature sensitive material. The heater circuits (13) raise the temperature of the connection points (12) to increase bond strength of a wire bond or to reflow a conductive bump to adhere to a connection point of another substrate.

Integrated circuit pad structure with high temperature heating element

Pressure sensors that are fabricated to sense low pressures are tested and calibrated by providing a controlled gas flow or leak to create a pressure during testing. Rather than placing the pressure sensor in a sealed environment, a controlled leak of a gas is used to induce a stable and controllable pressure region over the pressure sensor during testing. The stable low pressure region is monitored via a sensing tube.

Method for testing pressure sensors

A circuit (20) and a method for selecting a circuit module (M.sub.N) from a plurality of circuit modules (M.sub.0 -M.sub.N) coupled to a common bus (23). The circuit (20) includes a plurality of resistor divider networks (RD.sub.0 -RD.sub.N), wherein a single resistor divider network is coupled to a corresponding circuit module. Each resistor divider network (RD.sub.0 -RD.sub.N) provides the corresponding circuit module with an analog voltage upon initialization of the circuit (20). The analog voltage is converted into a digital voltage and serves as a unique address for the corresponding circuit module (M.sub.0 -M.sub.N). An analog electrical signal on the common bus (23) is converted into a digital electrical signal which is compared with the addresses of the plurality of circuit modules (M.sub.0 -M.sub.N). The circuit module having an address that matches the digital electrical signals is selected for receiving data or control signals from external circuitry.

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Gilbert, AZ, United States of America

Gary J O'Brien