Abstract:
The cellular structure of the power device includes a substrate that has a highly doped drain region. Over the substrate there is a more lightly doped epitaxial layer of the same doping. Above the epitaxial layer is a well region formed of an opposite type doping. Covering the wells is an upper source layer of the first conductivity type that is heavily doped. The trench structure includes a sidewall oxide or other suitable insulating material that covers the sidewalls of the trench. The bottom of the trench is filled with a doped polysilicon shield. An interlevel dielectric such as silicon nitride covers the shield. The gate region is formed by another layer of doped polysilicon. A second interlevel dielectric, typically borophosphosilicate glass (BPSG) covers the gate. In operation, current flows vertically between the source and the drain through a channel in the well when a suitable voltage is applied to the gate.
Abstract:
An MOS power device a substrate comprises an upper layer having an upper surface and an underlying drain region, a well region of a first conductance type disposed in the upper layer over the drain region, and a plurality of spaced apart buried gates, each of which comprises a trench that extends from the upper surface of the upper layer through the well region into the drain region. Each trench comprises an insulating material lining its surface, a conductive material filling its lower portion to a selected level substantially below the upper surface of the upper layer, and an insulating material substantially filling the remainder of the trench. A plurality of highly doped source regions of a second conductance type are disposed in the upper layer adjacent the upper portion of each trench, each source region extending from the upper surface to a depth in the upper layer selected to provide overlap between the source regions and the conductive material in the trenches. A groove in each of the highly doped source regions extends through the source regions into the well region and terminates in a nadir. A highly doped body region of a first conductance type is disposed in the well region adjacent both to the nadir of one or more of the grooves and to adjacent source regions penetrated by the grooves. A conductive layer is disposed over the substrate and electrically contacts the body and source regions. A process for fabricating a device produces an MOS power device that avoids the loss of channel width and provides reduced channel resistance without sacrificing device ruggedness and dynamic characteristics.
Abstract:
An improved trench MOS-gated device comprises a monocrystalline semiconductor substrate on which is disposed a doped upper layer. The upper layer includes at an upper surface a plurality of heavily doped body regions having a first polarity and overlying a drain region. The upper layer further includes at its upper surface a plurality of heavily doped source regions having a second polarity opposite that of the body regions A gate trench extends from the upper surface of the upper layer to the drain region and separates one source region from another. The trench has a floor and sidewalls comprising a layer of dielectric material and contains a conductive gate material filled to a selected level and an isolation layer of dielectric material that overlies the gate material and substantially fills the trench. The upper surface of the overlying layer of dielectric material in the trench is thus substantially coplanar with the upper surface of the upper layer. A process for forming an improved MOS-gate device provides a device whose gate trench is filled to a selected level with a conductive gate material, over which is formed an isolation dielectric layer whose upper surface is substantially coplanar with the upper surface of the upper layer of the device.
Abstract:
A semiconductor device includes at least one device active region formed in a first surface of a semiconductor substrate, an electrical contact layer on a second surface of the semiconductor substrate, and at least one resistivity-lowering body positioned in a corresponding recess in the substrate and connected to the electrical contact layer. The body preferably comprises a material having an electrical resistivity lower than an electrical resistivity of the semiconductor substrate to thereby lower an effective electrical resistivity of the substrate. The device active region may be an active region of a power control device, such as a MOSFET or IGBT, for example. The body may preferably comprise an electrical conductor such as copper, aluminum, silver, solder, or doped polysilicon. The at least one recess and associated resistivity-lowering body preferably defines a proportion of the semiconductor substrate area adjacent the device active region greater than about 0.4 percent, and may extend into the semiconductor substrate a distance greater than about 25 percent of a thickness of the substrate.
Abstract:
In one embodiment, a method of recommending a production plan includes calculating a similarity score between an incoming order and each historical order in a historical order database, providing a list of most similar historical orders and corresponding historical production plans ranked according to highest similarity scores, receiving an election indicating a historical production plan as a selected production plan, and admitting the selected historical production plan to fulfill the incoming order.
Abstract:
A system that generates risk values for a print service provider. The print service provider may calculate probabilities of an event occurring, calculate the effect that the given event will have on the print service provider, and determine various risks associated with calculations. These risks may then be utilized to determine overall operational strategies for the print service provider when compared to threshold risk levels for the print service provider.
Abstract:
A system that generates risk values for a print service provider. The print service provider may calculate probabilities of an event occurring, calculate the effect that the given event will have on the print service provider, and determine various risks associated with calculations. These risks may then be utilized to determine overall operational strategies for the print service provider when compared to threshold risk levels for the print service provider.
Abstract:
A system for print service provider (PSP) operations management includes a provenance analytics engine. The provenance analytics engine accesses fresh meta-data associated with fresh events in a PSP operation performed using a printing system operated by a PSP. The provenance analytics engine further accesses stored meta-data associated with past events related to past PSP operations. Still further, the provenance analytics engine accesses a component behavioral model (CBM) to produce results associated with events in a PSP operation. The provenance analytics engine analyzes the event-related meta-data.
Abstract:
A traveling wave dielectrophoresis display includes a display cell and a plurality of first particles contained within the display cell, the plurality of first particles having a first color. A plurality of electrodes in proximity to the display cell and generate a traveling wave dielectrophoresis field which distributes the plurality of first particles within the display cell to alter its optical characteristics.
Abstract:
Lateral power devices where immobile electrostatic charge is emplaced in dielectric material adjoining the drift region. A shield gate is interposed between the gate electrode and the drain, to reduce the Miller charge. In some embodiments the gate electrode is a trench gate, and in such cases the shield electrode too is preferably vertically extended.