Fairchild Semiconductor Corporation

Fairchild Semiconductor Corporatiion

Nathan Lawrence Kraft

Christopher Boguslaw Kocon

Hamza Yilmaz

Steven Paul Sapp

Daniel S Calafut

Thomas E Grebs

Joseph Andrew Yedinak

Rodney S Ridley

Ashok Challa

Gary M Dolny

Dean E Probst

Bruce Douglas Marchant

Paul Thorup

Richard Stokes

Louise E Skurkey

Rodney S Ridley, Sr

In one general aspect, a method can include forming a shield dielectric layer in a trench in a semiconductor substrate, forming a shield electrode on at least a portion of the shield dielectric layer, and etching the shield dielectric layer so that a portion of the shield dielectric layer is recessed in the trench. The method can include forming a gate dielectric layer on the recessed portion of the shield dielectric layer in the trench, forming a first conductive gate electrode on a first side of the shield electrode and insulated from a first sidewall of the trench by the gate dielectric layer, and forming a second conductive gate electrode on a second side of the shield electrode and insulated from a second sidewall of the trench by the gate dielectric layer.

Methods of manufacturing power semiconductor devices with trenched shielded split gate transistor

A field effect transistor (FET) includes a body region of a first conductivity type disposed within a semiconductor region of a second conductivity type and a gate trench extending through the body region and terminating within the semiconductor region. The FET also includes a flared shield dielectric layer disposed in a lower portion of the gate trench, the flared shield dielectric layer including a flared portion that extends under the body region. The FET further includes a conductive shield electrode disposed in the trench and disposed, at least partially, within the flared shield dielectric.

Trench-gate field effect transistor

In one general aspect, an apparatus can include a trench disposed in a semiconductor region, a shield dielectric layer lining a lower portion of a sidewall of the trench and a bottom surface of the trench, and a gate dielectric lining a upper portion of the sidewall of the trench. The apparatus can also include a shield electrode disposed in a lower portion of the trench and insulated from the semiconductor region by the shield dielectric layer, and an inter-electrode dielectric (IED) disposed in the trench over the shield electrode where the shield electrode has a curved top surface.

Shielded gate field effect transistors

A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches includes a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.

Field effect transistor with gated and non-gated trenches

Field effect transistor with source, heavy body region and shielded gate

A method of forming a shielded gate field effect transistor includes: forming a plurality of active gate trenches in a silicon region; lining lower sidewalls and bottom of the active gate trenches with a shield dielectric; using a CMP process, filling a bottom portion of the active gate trenches with a shield electrode comprising polysilicon; forming an interpoly dielectric (IPD) over the shield electrode in the active gate trenches; lining upper sidewalls of the active gate trenches with a gate dielectric; and forming a gate electrode over the IPD in an upper portion of the active gate trenches.

Method of forming shielded gate power transistor utilizing chemical mechanical planarization

A field effect transistor includes a gate trench extending into a semiconductor region. The gate trench has a recessed gate electrode disposed therein. A source region in the semiconductor region flanks each side of the gate trench. A conductive material fills an upper portion of the gate trench so as to make electrical contact with the source regions along upper sidewalls of the gate trench. The conductive material is insulated from the recessed gate electrode.

Structure and method for forming trench-gate field effect transistor with source plug

Methods of manufacturing power semiconductor devices include forming an epitaxial and dielectric layer, patterning and etching the dielectric layer, forming a first oxide layer, forming a first conductive layer on top of the first oxide layer, etching the first conductive layer away inside an active trench, forming a second oxide layer and second conductive layer. The second conductive layer does not extend completely over the first conductive layer in a first region outside of the active trench. The methods further include forming a third oxide layer over the second conductive layer, etching a first opening through the third oxide layer exposing the second conductive layer outside the active trench, etching a second opening through the second oxide layer outside the active trench in the first region exposing the first conductive layer but not the second conductive layer, and filling the first and second openings with conductive material.

Methods of manufacturing power semiconductor devices with shield and gate contacts

A method of forming a field effect transistor includes: forming a trench in a semiconductor region; forming a shield electrode in the trench; performing an angled sidewall implant of impurities of the first conductivity type to form a channel enhancement region adjacent the trench; forming a body region of a second conductivity type in the semiconductor region; and forming a source region of the first conductivity type in the body region, the source region and an interface between the body region and the semiconductor region defining a channel region therebetween, the channel region extending along the trench sidewall. The channel enhancement region partially extends into a lower portion of the channel region to thereby reduce a resistance of the channel region.

Method of forming trench-gate field effect transistors

A semiconductor power device includes active trenches that define an active area and an edge area that is located outside of the active area. The active trenches include a lower shield poly, an upper gate poly, a first oxide layer and a second oxide layer wherein the first oxide layer separates the lower shield poly from the upper gate poly and the second oxide layer covers the upper gate poly. The lower shield poly, upper gate poly, first oxide layer and second oxide layer conform to the shapo of the active trench and extend from the active trench to a surface of the edge area. The edge area includes a first opening that extends through the first oxide layer to the lower shield poly and a second opening that extends through the second oxide layer to the upper gate poly.

Power semiconductor devices with shield and gate contacts and methods of manufacture

A semiconductor power device includes a drift region of a first conductivity type, a well region extending above the drift region and having a second conductivity type opposite the first conductivity type, active trenches extending through the well region and into the drift region where the active trenches define an active area. Inside each of the active trenches is formed a first conductive gate electrode disposed along and insulated from a first trench sidewall, a second conductive gate electrode disposed along and insulated from a second trench sidewall, and a conductive shield electrode disposed between the first and second conductive gate electrodes, wherein the shield electrode is insulated from and extends deeper inside the trench than the first and second conductive gate electrodes. The device also includes source regions having the first conductivity type formed inside the well region and adjacent the active trenches. Electrical contact to the conductive shield electrode can be made inside the active area. The device can also include a perimeter trench extending at least partially around the active trenches such that at least some of the active trenches are perpendicular to the perimeter trench, gate fingers extending from a perimeter gate poly runner located in said perimeter trench, and shield poly fingers extending from a perimeter shield poly runner located in the perimeter trench. The gate fingers are staggered with respect to the shield poly fingers.

Power semiconductor devices with trenched shielded split gate transistor and methods of manufacture

A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches include a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench.

Field effect transistor with self-aligned source and heavy body regions and method of manufacturing same

A trench is formed in a semiconductor region. A dielectric layer lining sidewalls and bottom surface of the trench is formed. The dielectric layer is thicker along lower sidewalls and the bottom surface than along upper sidewalls of the trench. After forming the dielectric layer, a lower portion of the trench is filled with a shield electrode. Dielectric spacers are formed along the upper trench sidewalls. After forming the dielectric spacers, an inter-electrode dielectric (IED) is formed in the trench over the shield electrode. After forming the IED, the dielectric spacers are removed.

Method for forming shielded gate field effect transistor using spacers

A field effect transistor includes a body region of a first conductivity type in a semiconductor region of a second conductivity type. A gate trench extends through the body region and terminating within the semiconductor region. A source region of the second conductivity type extends in the body region adjacent the gate trench. The source region and an interface between the body region and the semiconductor region define a channel region therebetween which extends along the gate trench sidewall. A channel enhancement region of the second conductivity type is formed adjacent the gate trench. The channel enhancement region partially extends into a lower portion of the channel region to thereby reduce a resistance of the channel region.

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Pottsville, PA, United States of America

Nathan Lawrence Kraft