Abstract: Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.

Abstract: Exemplary power semiconductor devices with features providing increased breakdown voltage and other benefits are disclosed.

Abstract: A method and device for protecting wide bandgap devices from failing during suppression of voltage transients. An improvement in avalanche capability is achieved by placing one or more diodes, or a PNP transistor, across the blocking junction of the wide bandgap device.

Abstract: A charge balance semiconductor power device comprises an active area having strips of p pillars and strips of n pillars arranged in an alternating manner, the strips of p and n pillars extending along a length of the active area. A non-active perimeter region surrounds the active area, and includes at least one p ring surrounding the active area. One end of at last one of the strips of p pillars extending immediately adjacent an edge of the active area terminates at a substantially straight line at which one end of each of the remainder of the strips of p pillars also end. The straight line extends perpendicular to the length of the active area along which the strips of n and p pillars extend.

Abstract: A field effect transistor includes a body region of a first conductivity type over a semiconductor region of a second conductivity type. A gate trench extends through the body region and terminates within the semiconductor region. At least one conductive shield electrode is disposed in the gate trench. A gate electrode is disposed in the gate trench over but insulated from the at least one conductive shield electrode. A shield dielectric layer insulates the at lease one conductive shield electrode from the semiconductor region. A gate dielectric layer insulates the gate electrode from the body region. The shield dielectric layer is formed such that it flares out and extends directly under the body region.

Abstract: A wide bandgap device in parallel with a device having a lower avalanche breakdown voltage and a higher forward voltage drop than the wide bandgap device.

Abstract: 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.

Abstract: A method for forming a shielded gate field effect transistor includes the following steps. Trenches extending into a silicon region are formed using a mask that includes a protective layer. A shield dielectric layer lining sidewalls and bottom of each trench is formed. A shield electrode is formed in a bottom portion of each trench. Protective spacers are formed along upper sidewalls of each trench. An inter-electrode dielectric is formed over the shield electrode. The protective spacers and the protective layer of the mask prevent formation of inter-electrode dielectric along the upper sidewalls of each trench and over mesa surfaces adjacent each trench. A gate electrode is formed in each trench over the inter-electrode dielectric.

Abstract: 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 shape 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. The first opening is filled with a conductive material that makes electrical contact with the lower shield poly and the second opening is filled with conductive material that makes electrical contact with the upper gate poly.

Abstract: 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.

Abstract: A field effect transistor is formed as follows. Trenches are formed in a semiconductor region of a first conductivity type. Each trench is partially filled with one or more materials. A dual-pass angled implant is carried out to implant dopants of a second conductivity type into the semiconductor region through an upper surface of the semiconductor region and through upper trench sidewalls not covered by the one or more material. A high temperature process is carried out to drive the implanted dopants deeper into the mesa region thereby forming body regions of the second conductivity type between adjacent trenches. Source regions of the first conductivity type are then formed in each body region.

Abstract: 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, an active trench extending through the well region and into the drift region. The active trench, which includes sidewalls and bottom lined with dielectric material, is substantially filled with a first conductive layer and a second conductive layer. The second conductive layer forms a gate electrode and is disposed above the first conductive layer and is separated from the first conductive layer by an inter-electrode dielectric material. The device also includes source regions having the first conductivity type formed inside the well region and adjacent the active trench and a charge control trench that extends deeper into the drift region than the active trench and is substantially filled with material to allow for vertical charge control in the drift region.

Abstract: 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, an active trench extending through the well region and into the drift region, source regions having the first conductivity type formed in the well region adjacent the active trench, and a first termination trench extending below the well region and disposed at an outer edge of an active region of the device. The sidewalls and bottom of the active trench are lined with dielectric material, and substantially filled with a first conductive layer forming an upper electrode and a second conductive layer forming a lower electrode, the upper electrode being disposed above the lower electrode and separated therefrom by inter-electrode dielectric material.

Abstract: A method and device for protecting wide bandgap devices from failing during suppression of voltage transients. An improvement in avalanche capability is achieved by placing one or more diodes, or a PNP transistor, across the blocking junction of the wide bandgap device.

Abstract: A charge balance semiconductor power device comprises an active area having strips of p pillars and strips of n pillars arranged in an alternating manner, the strips of p and n pillars extending along a length of the active area. A non-active perimeter region surrounds the active area, and includes at least one p ring surrounding the active area. One end of at last one of the strips of p pillars extending immediately adjacent an edge of the active area terminates at a substantially straight line at which one end of each of the remainder of the strips of p pillars also end. The straight line extends perpendicular to the length of the active area along which the strips of n and p pillars extend.

Abstract: An IGBT includes a first silicon region over a collector region, and a plurality of pillars of first and second conductivity types arranged in an alternating manner over the first silicon region. The IGBT further includes a plurality of well regions each extending over and being in electrical contact with one of the pillars of the first conductivity type, and a plurality of gate electrodes each extending over a portion of a corresponding well region. The physical dimensions of each of the first and second conductivity type pillars and the doping concentration of charge carriers in each of the first and second conductivity type pillars are selected so as to create a charge imbalance between a net charge in each pillar of first conductivity and a net charge in its adjacent pillar of the second conductivity type.

Abstract: An integrated circuit includes a die having a device layer. An insulating layer is disposed over the device layer. A die street defines the outermost bounds of the die. A voltage divider network including a plurality of resistive elements derives a plurality of predetermined bias voltages. A field plate termination includes a plurality of field plates disposed on the oxide layer and are laterally spaced apart relative to each other and relative to the die street. Each of the plurality of field plates is electrically connected to a corresponding bias voltage. The bias voltage applied to a given field plate is determined by and increases with the proximity of that field plate relative to the die street.

Abstract: A field effect transistor is formed as follows. Trenches are formed in a semiconductor region of a first conductivity type. Each trench is partially filled with one or more materials. A dual-pass angled implant is carried out to implant dopants of a second conductivity type into the semiconductor region through an upper surface of the semiconductor region and through upper trench sidewalls not covered by the one or more material. A high temperature process is carried out to drive the implanted dopants deeper into the mesa region thereby forming body regions of the second conductivity type between adjacent trenches. Source regions of the first conductivity type are then formed in each body region.

Abstract: A field effect transistor is formed as follows. A trench is formed in a semiconductor region. A dielectric layer lining the trench sidewalls and bottom is formed. The trench is filled with a conductive material. The conductive material is recessed into the trench to thereby form a shield electrode in a bottom portion of the trench. The recessing of the conductive material includes isotropic etching of the conductive material. An inter-electrode dielectric (IED) is formed over the recessed shield electrode.

Abstract: A field effect transistor includes a body region of a first conductivity type over a semiconductor region of a second conductivity type. A gate trench extends through the body region and terminates within the semiconductor region. At least one conductive shield electrode is disposed in the gate trench. A gate electrode is disposed in the gate trench over but insulated from the at least one conductive shield electrode. A shield dielectric layer insulates the at lease one conductive shield electrode from the semiconductor region. A gate dielectric layer insulates the gate electrode from the body region. The shield dielectric layer is formed such that it flares out and extends directly under the body region.