International Rectifier Corporation

Infineon Technologies Americas Corp.

Timothy Donald Henson

Ling Ma

Kapil Kelkar

Hugo R Burke

Jianjun Cao

Robert Paul Haase

Niraj Ranjan

David Paul Jones

Ljubo Radic

Dev Alok Girdhar

Adam Amali

Mary Bigglestone

Kyle A Spring

Ashita Mirchandani

Vijay Viswanathan

Andrew Neil Sawle

Naresh Thapar

Igor Bol

Harsh Naik

Martin Carroll

Alain Charles

Aram Arzumanyan

Paul Harvey

David Kent

Omar Hassen

Disclosed is a power device, such as power MOSFET, and method for fabricating same. The device includes an upper trench situated over a lower trench, where the upper trench is wider than the lower trench. The device further includes a trench dielectric inside the lower trench and on sidewalls of the upper trench. The device also includes an electrode situated within the trench dielectric. The trench dielectric of the device has a bottom thickness that is greater than a sidewall thickness.

Method of fabricating a power semiconductor device

A power semiconductor device includes a semiconductor substrate having a drift region, a gate electrode trench in the semiconductor substrate and a field electrode needle trench in the semiconductor substrate. The gate electrode trench extends into the drift region and includes a gate electrode. The gate electrode is arranged in the gate electrode trench and electrically insulated from the drift region by a gate dielectric layer arranged between the gate electrode and the drift region. The field electrode needle trench is laterally spaced from the gate electrode trench and extends into the drift region. The field electrode needle trench includes a field electrode arranged in the field electrode needle trench and electrically insulated from the drift region by a cavity formed between the field electrode and the drift region.

Semiconductor device having a cavity

According to an exemplary implementation, a field-effect transistor (FET) includes first and second gate trenches extending to a drift region of a first conductivity type. The FET also includes a base region of a second conductivity type that is situated between the first and second gate trenches. A ruggedness enhancement region is situated between the first and second gate trenches, where the ruggedness enhancement region is configured to provide an enhanced avalanche current path from a drain region to the base region when the FET is in an avalanche condition. The enhanced avalanche current path is away from the first and second gate trenches. The ruggedness enhancement region can be of the second conductivity type that includes a higher dopant concentration than the base region. Furthermore, the ruggedness enhancement region can be extending below the first and second gate trenches.

Trench FET with ruggedness enhancement regions

A semiconductor structure is disclosed. The semiconductor structure includes a source trench in a drift region, the source trench having a source trench dielectric liner and a source trench conductive filler surrounded by the source trench dielectric liner, a source region in a body region over the drift region. The semiconductor structure also includes a patterned source trench dielectric cap forming an insulated portion and an exposed portion of the source trench conductive filler, and a source contact layer coupling the source region to the exposed portion of the source trench conductive filler, the insulated portion of the source trench conductive filler increasing resistance between the source contact layer and the source trench conductive filler under the patterned source trench dielectric cap. The source trench is a serpentine source trench having a plurality of parallel portions connected by a plurality of curved portions.

Method of forming a semiconductor structure having integrated snubber resistance

Disclosed is a power semiconductor device that includes a plurality of source trenches and adjacent source regions. The plurality of source trenches extend from a top surface of a semiconductor substrate into the semiconductor substrate. The power semiconductor device further includes a plurality of gate trenches that extend from the top of the semiconductor substrate into the semiconductor substrate, and are arranged in hexagonal or zigzag patterns. A contiguous formation is created by the plurality of gate trenches, and the plurality of gate trenches separate the plurality of source trenches from one another.

Power semiconductor device with contiguous gate trenches and offset source trenches

A power semiconductor device is disclosed. The power semiconductor device includes an upper drift region situated over a lower drift region, a field electrode embedded in the lower drift region, the field electrode not being directly aligned with a gate trench in a body region of the power semiconductor device, where respective top surfaces of the field electrode and the lower drift region are substantially co-planar. A conductive filler in the field electrode can be substantially uniformly doped, and the field electrode is in direct electrical contact with the upper drift region.

Power semiconductor device with embedded field electrodes

Semiconductor device with a field plate double trench having a thick bottom dielectric

A method for manufacturing a semiconductor device includes: providing a semiconductor substrate; forming at least one recess in the semiconductor substrate; the recess having a bottom and a sidewall; forming an auxiliary structure on the sidewall and the bottom of the recess and forming a hollow space within the recess; filling the hollow space of the recess with a filling material for forming a filling structure in the recess; removing portions of the auxiliary structure from the sidewall of the recess so as to form at least one cavity between the filling structure and the sidewall of the recess; and sealing the cavity at the first side of the semiconductor substrate.

Semiconductor device having a cavity and method for manufacturing thereof

A semiconductor device includes a semiconductor substrate having a base region situated over a drift region, a source trench extending through the base region and into the drift region, the source trench having a shield electrode, a gate trench extending through the base region and into the drift region, the gate trench adjacent the source trench, the gate trench having a gate electrode situated above a buried electrode. The source trench is surrounded by the gate trench. The shield electrode is coupled to a source contact over the semiconductor substrate. The semiconductor device also includes a source region over the base region. The gate trench includes gate trench dielectrics lining a bottom and sidewalls of the gate trench. The source trench includes source trench dielectrics lining a bottom and sidewalls of the source trench.

Semiconductor device including a gate trench having a gate electrode located above a buried electrode

Disclosed is a method for fabricating a shallow and narrow trench field-effect transistor (trench FET). The method includes forming a trench within a semiconductor substrate of a first conductivity type, the trench including sidewalls and a bottom portion. The method further includes forming a substantially uniform gate dielectric in the trench, and forming a gate electrode within said trench and over said gate dielectric. The method also includes doping the semiconductor substrate to form a channel region of a second conductivity type after forming the trench. In one embodiment, the doping step is performed after forming the gate dielectric and after forming the gate electrode. In another embodiment, the doping step is performed after forming the gate dielectric, but prior to forming the gate electrode. Structures formed by the invention's method are also disclosed.

Method for fabricating a shallow and narrow trench FET and related structures

Semiconductor structure having integrated snubber resistance

A power semiconductor device is disclosed. The power semiconductor device includes a source region in a body region, a gate trench adjacent to the source region, and a source trench electrically coupled to the source region. The source trench includes a source trench conductive filler surrounded by a source trench dielectric liner, and extends into a drift region. The power semiconductor device includes a source trench implant below the source trench and a drain region below the drift region, where the source trench implant has a conductivity type opposite that of the drift region. The power semiconductor device may also include a termination trench adjacent to the source trench, where the termination trench includes a termination trench conductive filler surrounded by a termination trench dielectric liner. The power semiconductor device may also include a termination trench implant below the termination trench.

Power semiconductor device with source trench and termination trench implants

In one implementation, a vertical field-effect transistor (FET) includes a substrate having a drift region situated over a drain, a body region situated over the drift region and having source diffusions formed therein, a gate trench extending through the body region, and channel regions adjacent the gate trench. The channel regions are spaced apart along the gate trench by respective deep body implants. Each of the deep body implants is situated approximately under at least one of the source diffusions, and has a depth greater than a depth of the gate trench.

Vertical FET having reduced on-resistance

Disclosed is a power device, such as a power MOSFET, and methods for fabricating same. The device includes a field plate trench. The device further includes first and second trench dielectrics inside the field plate trench. The device also includes a field plate situated over the first trench dielectric and within the second trench dielectric. A combined thickness of the first and second trench dielectrics at a bottom of the field plate trench is greater than a sidewall thickness of the second trench dielectric.

Semiconductor device with a field plate trench having a thick bottom dielectric

Disclosed is a power device, such as a power MOSFET device and a method for fabricating same. The device includes a field plate trench. The field plate trench has a predetermined width and a predetermined sidewall angle. The device further includes a single trench dielectric on sidewalls of the field plate trench and at a bottom of the field plate trench. The single trench dielectric has a bottom thickness that is greater than a sidewall thickness. The device also includes a field plate situated within the single trench dielectric.

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Torrance, CA, United States of America

Timothy Donald Henson