Psemi Corporation

Murata Manufacturing Co., Ltd.

Peregrine Semiconductor Corporation

Soitec

Alain Duvallet

Simon Edward Willard

Abhijeet Paul

Hiroshi Yamada

Sinan Goktepeli

Befruz Tasbas

Ronald Eugene Reedy

Buddhika Abesingha

Merlin Green

Sivakumar Kumarasamy

Richard James Dowling

Anthony Mark Miscione

Bich-Yen Nguyen

George P Imthurn

Christophe Maleville

Christopher F O'Brien

Hiroshi Domyo

Michael McCafferty

Masaki Sato

A FET IC structure made using a back-side access process that mitigates or eliminates thermal conductivity problems. In some embodiments, electrically-isolated thermal paths are formed adjacent the FET and configured to conduct heat laterally away from the FET to generally orthogonal thermal pathways, and thence to thermal pads externally accessible at the 'top' of the completed IC. In some embodiments having a thermally-conductive handle wafer, electrically-isolated thermal paths are formed adjacent a FET and configured to conduct heat laterally away from the FET. Thermal vias are formed sufficiently so as to be in thermal contact with the handle wafer and with the conventional metallization layers of the device superstructure, at least one of which is in thermal contact with the lateral thermal paths. In some embodiments, the lateral thermal paths may use dummy gates configured to conduct heat laterally away from a FET to generally orthogonal thermal pathways.

Thermal extraction of single layer transfer integrated circuits

FET designs that exhibit low leakage in the presence of the edge transistor phenomenon. Embodiments includes nFET designs in which the work function Φof the gate structure overlying the edge transistors of the nFET is increased by forming extra P+ implant regions within at least a portion of the gate structure, thereby increasing the Vt of the edge transistors to a level that may exceed the Vt of the central conduction channel of the nFET. In some embodiments, the gate structure of the nFET is modified to increase or 'flare' the effective channel length of the edge transistors relative to the length of the central conduction channel of the FET. Other methods of changing the work function Φof the gate structure overlying the edge transistors are also disclosed. The methods may be adapted to fabricating pFETs by reversing or substituting material types.

Low leakage FET

Systems, methods, and apparatus for an improved protection from charge injection into layers of a device using resistive structures are described. Such resistive structures, named s-contacts, can be made using simpler fabrication methods and less fabrication steps. In a case of metal-oxide-semiconductor (MOS) field effect transistors (FETs), s-contacts can be made with direct connection, or resistive connection, to all regions of the transistors, including the source region, the drain region and the gate.

S-contact for SOI

FET IC structures that enable formation of integrated capacitors in a 'flipped' SOI IC structure made using a back-side access process, such as a “single layer transfer” (SLT) process, and which eliminate or mitigate unwanted parasitic couplings to a handle wafer. In some embodiments, a conductive interconnect layer may be patterned, pre-SLT, to form an isolated first capacitor plate. In other embodiments, pre-SLT, a conductive region of the active layer of an IC may be patterned to form an isolated first capacitor plate, with one or more interconnect layers being fabricated in position to form an electrical contact to the first capacitor plate. In either case, a post-SLT top-side layer of conductive material may be patterned to form a second capacitor plate. Couplings to the resulting capacitor structures include only external connections, only internal connections, or both internal and external connections

SLT integrated circuit capacitor structure and methods

A high-voltage switching device that can be fabricated in a standard low-voltage process, such as CMOS, and more specifically SOI CMOS. Embodiments include integrated circuits that combine, in a unitary structure, a FET device and an integrated, co-fabricated modulated resistance region (MRR) controlled by one or more Voltage-Drop Modulation Gates (VDMGs). The VDMGs are generally biased independently of the gate of the FET device, and in such a way as to protect each VDMG from excessive and potentially destructive voltages. In a first embodiment, an integrated circuit high voltage switching device includes a transistor structure including a source, a gate, and an internal drain; an MRR connected to the internal drain of the transistor structure; at least one VDMG that controls the resistance of the MRR; and a drain electrically connected to the MRR. Each VDMG at least partially depletes the MRR upon application of a bias voltage.

High voltage switching device

FET IC structures that enable formation of integrated capacitors in a 'flipped' SOI IC structure made using a back-side access process, such as a 'single layer transfer' (SLT) process, and which eliminate or mitigate unwanted parasitic couplings to a handle wafer. In some embodiments, a conductive interconnect layer may be patterned, pre-SLT, to form an isolated first capacitor plate. In other embodiments, pre-SLT, a conductive region of the active layer of an IC may be patterned to form an isolated first capacitor plate, with one or more interconnect layers being fabricated in position to form an electrical contact to the first capacitor plate. In either case, a post-SLT top-side layer of conductive material may be patterned to form a second capacitor plate. Couplings to the resulting capacitor structures include only external connections, only internal connections, or both internal and external connections.

FET designs that exhibit low leakage in the presence of the edge transistor phenomenon. Embodiments includes nFET designs in which the work function &#x3a6;of the gate structure overlying the edge transistors of the nFET is increased by forming extra P+ implant regions within at least a portion of the gate structure, thereby increasing the Vt of the edge transistors to a level that may exceed the Vt of the central conduction channel of the nFET. In some embodiments, the gate structure of the nFET is modified to increase or 'flare' the effective channel length of the edge transistors relative to the length of the central conduction channel of the FET. Other methods of changing the work function &#x3a6;of the gate structure overlying the edge transistors are also disclosed. The methods may be adapted to fabricating pFETs by reversing or substituting material types.

Structures and fabrication methods for transistors having low parasitic capacitance, the transistors including an insulating low dielectric constant first or second handle wafer. In one embodiment, a Single Layer Transfer technique is used to position an insulating LDC handle wafer proximate the metal interconnect layers of an SOI transistor/metal layer stack in lieu of the silicon substrate of conventional designs. In another embodiment, a Double Layer Transfer technique is used to replace the silicon substrate of prior art structures with an insulating LDC substrate. In some embodiments, the insulating LDC handle wafer includes at least one air cavity, which reduces the effective dielectric constant of material surrounding an RF FET. An insulating LDC handle wafer reduces insertion loss and non-linearity, increases isolation, provides for more ideal voltage division of stacked transistors, enables a higher Q factor due to lower coupling losses, and otherwise mitigates various parasitic effects.

Low parasitic capacitance RF transistors

Systems, methods and apparatus for coexistence of high voltage and low voltage devices and circuits on a same integrated circuit fabricated in silicon-on-insulator (SOI) technology are described. In particular, techniques for mitigating back gate effects are described, including using of resistive and/or capacitive couplings to control surface potentials at regions of a substrate used for the SOI fabrication proximate the high voltage and low voltage devices and circuits. In one case, an N-type implant is used to provide a high potential differential with respect to a substrate potential.

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San Diego, CA, United States of America

Alain Duvallet