Motorola Corporation

Magfusion Inc.

Schneider Electric Industries Sas

Tam, Gordon

Shen, Jun

Stafford, John

Gordon Tam

Jun Shen

Pak M Tam

John Stafford

Meichun Ruan

Ganming Qin

Ronald N Legge

Wayne M Paulson

Chengping Wei

Rimantas L Vaitkus

Barry O'Brien

Lynnita K Knoch

Shang-Hui Larry Tu

Prasad S Godavarti

Lisa R Granick

A micro-magnetic switch includes a permanent magnet and a supporting device having contacts coupled thereto and an embedded coil. The supporting device can be positioned proximate to the magnet. The switch also includes a cantilever coupled at a central point to the supporting device. The cantilever has a conducting material coupled proximate an end and on a side of the cantilever facing the supporting device and having a soft magnetic material coupled thereto. During thermal cycling the cantilever can freely expand based on being coupled at a central point to the supporting device, which substantially reduces coefficient of thermal expansion differences between the cantilever and the supporting device.

Latching micro-magnetic switch with improved thermal reliability

Described is a process to pattern adhesion and top contact layers in such a way that at least some portion of the top contact layers overlaps the adhesion layer, while another portion of the top contact layer overlaps with the bottom contacts, but does not overlap with the adhesion layer. The overlap between the top contact layer and the adhesion layer helps to hold the top contact layer onto the sacrificial layer. Because there is no overlap between the adhesion layer and the bottom contact, the removal of adhesion layer is no longer necessary, leading to better contacts and simplifying the fabrication process.

Method for fabricating a gold contact on a microswitch

Radio frequency (RF) switch comprising an electromagnet formed on a magnet, a transmission line formed on the electromagnet and having a ground line and a signal line, and a movable contact connected to either the ground line or the signal line and capable of electrically coupling the ground line with the signal line. The transmission line is capable of propagating a RF signal if the ground line is electrically decoupled from the signal line. Conversely, the transmission line is incapable of propagating a RF signal if the ground line is electrically coupled with the signal line. The electromagnet can comprise an electromagnetic coil, formed in a layer of dielectric material, electrically coupled to a current source. Preferably, the movable contact is capable of being magnetically actuated, and is latchable. The magnet, the electromagnet, the transmission line, and the movable contact can have dimensions at a micron order of magnitude. The transmission line can be a coplanar waveguide. The coplanar waveguide can include a ground plane positioned between a layer of dielectric material and the electromagnet. The coplanar waveguide can also include means to electrically couple the ground plane to the ground line.

Latchable, magnetically actuated, ground plane-isolated radio frequency microswitch

A method of forming a hermetically sealed MEMS package includes a step of providing a supporting GaAs substrate with at least one contact for the MEMS device on the surface of the supporting substrate and forming a cantilever on the surface of the supporting substrate positioned to come into electrical engagement with the contact in one orientation. A metal seal ring is fixed to the surface of the supporting substrate circumferentially around the contact and the cantilever. A cavity is etched in a silicon chip to form a cap member. A metal seal ring is fixed to the cap member around the cavity. The package is hermetically sealed by reflowing a solder alloy, positioned between the two seal rings, in an inert environment without the use of flux.

Latching micro magnetic relay packages and methods of packaging

Packages for a micromachined magnetic latching switch, and methods for assembling the packages are described. In one aspect, a substrate is defined by opposing first and second surfaces. A micromagnetic switch integrated circuit (IC) chip is mounted to the first surface. A contact pad on the chip is coupled to a trace on the first surface. A permanent magnet is positioned closely adjacent to the chip. A cap is attached to the first surface. An inner surface of the cap forms an enclosure to enclose the chip on the first surface. The chip can be alternatively mounted to the inner surface of the cap. The chip can be oriented in a standard or flip-chip fashion. In another aspect, a moveable micro-machined cantilever is supported by a surface of a substrate. A cap is attached to the surface. An inner surface of the cap forms an enclosure that encloses the cantilever on the surface of the substrate. A permanent magnet is positioned closely adjacent to the cantilever. An electromagnet is attached to the inner surface or an outer surface of the cap.

Micromagnetic latching switch packaging

Micro magnetic switching apparatus includes a permanent magnet supported on a base and a coil supported by the base so as to define a plurality of sides. A plurality of latching micro magnetic relays each includes a magnetic cantilever positioned to open a first electric circuit in a first orientation and to close the first electric circuit in a second orientation. One each of the relays is mounted adjacent each of the plurality of sides of the coil and adjacent the permanent magnet so as to be latched in one of the first and second orientations when the coil is not activated and to switch to the other of the first and second orientations when the coil is activated and to be latched in the other of the first and second orientations by the permanent magnet.

Micro magnetic switching apparatus and method

A field emission device ( ) includes a cathode ( ) and a ballast resistor ( ) connected to cathode ( ). Ballast resistor ( ) includes a thin metallic layer ( ) and a protective layer ( ) disposed on metallic layer ( ). Metallic layer ( ) is made from chromium and has a thickness of about 40 angstroms. Protective layer ( ) is made from sputtered silicon and has a thickness of about 500 angstroms. A portion of metallic layer ( ) makes physical contact with cathode ( ) and is sandwiched between cathode ( ) and protective layer ( ). Protective layer ( ) is positioned to shield metallic layer ( ) from high transient voltages.

Field emission device having an improved ballast resistor

A high performance, high voltage non-epi bipolar transistor including a substrate (12) with an n-type conductivity well (13) and an insulative layer (14) with first (15), second (17) and third (18) openings exposing the substrate in the well. A first p-type volume (19) surrounding the first and second openings (15, 17) beneath the insulative layer (14), and a second n-type volume (22) surrounding the third opening (18) beneath the insulative layer (14). A p-type intrinsic base (25) in the first opening (15) and in contact with the first volume (19). A p-type extrinsic base (30) in the second opening (17) and in contact with the first volume (19). An n-type collector (32) in the third opening (18) and in contact with the second volume (22), and an n-type emitter layer (27) in the first opening in overlying contact with the intrinsic base (25).

Method of forming a high performance, high voltage non-epi bipolar

High performance, high voltage non-epibipolar transistor

A method of fabricating a fast-switching, low-R(on) insulated-gate bipolar transistor including providing an N-type semiconductor wafer with a planar surface, forming a thin heavily-doped layer, having a concentration in the range of 3.times.10.sup.17 /cm.sup.3 to 1.times.10.sup.19 /cm.sup.3, in the wafer adjacent the planar surface, providing a P-type semiconductor wafer, and bonding a surface of the P-type wafer to the planar surface of the N-type wafer. An emitter and a gate are then formed in the N-type wafer in the usual manner and a collector is formed on the P-type wafer.

Method of fabricating an insulated-gate bipolar transistor

A method for making a stable low threshold voltage p-channel power MOSFET device having a p-type gate layer (14) includes incorporating a p-type dopant into the gate layer (14) formed over a gate oxide layer (13). The p-type dopant is incorporated within the gate layer (14) under conditions that minimize diffusion of p-type dopant through the gate oxide layer (13) into the channel regions (31, 32). The process reduces the number of process steps necessary to manufacture a power MOSFET device.

Process for making a power MOSFET device and structure

A heterojunction bipolar transistor having a thin, lightly doped, silicon emitter disposed on a silicon-germanium base layer exhibits low emitter resistance and low emitter-base capacitance. The lightly doped silicon emitter maintains the bandgap differential between silicon-germanium and silicon. The silicon emitter is fabricated such that the silicon emitter will be substantially depleted at zero bias, resulting in low emitter-base resistance and emitter resistance.

Heterojunction bipolar transistor with a thin silicon emitter

A method for differentially etching silicon nitride, preferably formed in a hydrogen free environment, wherein hydrogen is implanted into various regions of the silicon nitride. The silicon nitride may then be etched by a number of different etchants, some of which will etch the implanted regions appreciably faster and others which will etch the non-implanted regions more quickly. This method is especially useful in the fabrication of self-aligned gate devices.

Differential etching of silicon nitride

An improved method of fabricating airbridge metal interconnects uses two photoresist layers having different solubility characteristics. This allows for the removal of one resist without affecting the other. Thus, the underlying semiconductor structure is protected from subsequent etches of the ground plane metal. Consequently, a greater process latitude allows for obtaining higher device yields in fabricating high frequency semiconductor devices employing airbridge metal interconnects.

Growing community of inventors

Gilbert, AZ, United States of America

Gordon Tam