摘要:
A method of fabricating a trench device includes forming a first trench and forming a hardmask layer on sidewalls of the trench. A second trench may be etched narrower than the first trench, into the bottom of the first trench. A dielectric material may be grown to substantially fill the second trench, using a reaction process to which the hardmask material is substantially inert. The growing action also grows tapered portions of the dielectric material upwardly under part of the hardmask. A conductive layer may be formed over said dielectric material. The dielectric material in the second trench, in combination with the tapered portions which extend upward from the dielectric material may provide smooth gradation of voltage differences within the semiconductor material. The gradation may be caused by potential differences between the gate and various portions of the semiconductor material.
摘要:
A method for manufacturing a trench MOSFET semiconductor device comprises: providing a heavily doped N+ silicon substrate; forming an N type epitaxial layer; forming a thick SiO2 layer; creating P body and source area formations by ion implantation without any masks; utilizing a first mask to define openings for a trench gate and a termination; thermally growing a gate oxide layer followed by formation of a thick poly-Silicon refill layer without a mask to define a gate bus area; forming sidewall spacers; forming P+ areas; removing the sidewall spacers; depositing tungsten to fill contacts and vias; depositing a first thin barrier metal layer; depositing a first thick metal layer; utilizing a second metal mask to open a gate bus area; forming second sidewall spacers; depositing a second thin barrier metal layer; depositing a second thick metal layer; and planarizing at least the second thick metal layer and the second thin metal layer to isolate the source metal portions from gate metal portions, whereby the trench MOSFET semiconductor device is manufactured utilizing only first and second masks.
摘要:
A silicon semiconductor die comprises a heavily doped silicon substrate and an upper layer comprising doped silicon of a first conduction type disposed on the substrate. The upper layer comprises a well region of a second, opposite conduction type adjacent an edge termination zone that comprises a layer of a material having a higher critical electric field than silicon. Both the well region and adjacent edge termination zone are disposed at an upper surface of the upper layer, and an oxide layer overlies the upper layer and the edge termination zone. A process for forming a silicon die having improved edge termination. The process comprises forming an upper layer comprising doped silicon of a first conduction type on a heavily doped silicon substrate, and forming an edge termination zone that comprises a layer of a material having a higher critical electric field than silicon at an upper surface of the upper layer. A well region of a second, opposite conduction type is formed at the upper surface of the upper layer adjacent the edge termination zone, and an oxide layer is formed over the upper layer and edge termination zone.
摘要:
A manufacturing process and a power junction field-effect transistor (JFET) are provided. The basic concept of the present invention is to allow the current to flow vertically from the drain region on the bottom side to the source region on the topside of the device. By regulating the voltage applied between the gate regions and the source region, the power junction field-effect transistor (JFET) of the present invention can be built to handle large current and higher voltage for power management purposes, as is similar to the metal oxide semiconductor field effect transistor (MOSFET).
摘要:
The present invention relates to a method for making shaped structures with internally coated cavities with an inside diameter in the nanometer to micrometer range and the shaped structure obtained thereby.
摘要:
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.
摘要:
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.
摘要:
A silicon semiconductor die comprises a heavily doped silicon substrate and an upper layer comprising doped silicon of a first conduction type disposed on the substrate. The upper layer comprises a well region of a second, opposite conduction type adjacent an edge termination zone that comprises a layer of a material having a higher critical electric field than silicon. Both the well region and adjacent edge termination zone are disposed at an upper surface of the upper layer, and an oxide layer overlies the upper layer and the edge termination zone. A process for forming a silicon die having improved edge termination. The process comprises forming an upper layer comprising doped silicon of a first conduction type on a heavily doped silicon substrate, and forming an edge termination zone that comprises a layer of a material having a higher critical electric field than silicon at an upper surface of the upper layer. A well region of a second, opposite conduction type is formed at the upper surface of the upper layer adjacent the edge termination zone, and an oxide layer is formed over the upper layer and edge termination zone.
摘要:
A power MOS device that has increased channel width comprises a semiconductor substrate and a doped upper layer of a first conduction type disposed on the substrate. The upper layer comprises a plurality of doped well regions of a second, opposite conduction type and a plurality of heavily doped source regions of the first conduction type at an etched upper surface of the upper layer that comprises parallel corrugations disposed transversely to the source regions. A gate that separates one source region from another comprises an insulating layer and a conductive material. The corrugations provide an increase in width of a channel underlying the gate and the well and source regions. In a process for forming a power MOS device with increased channel width on a semiconductor substrate having a doped upper layer of a first conduction type, a stripe mask is formed on an upper surface of the upper layer, and the upper surface is selectively etched to form a corrugated surface comprising a plurality of parallel corrugations. Following removal of the stripe mask, an insulating layer is formed on the corrugated surface, and an overlying conductive layer is formed on the insulating layer, the insulating and conductive layers comprising a corrugated gate region disposed transversely to the parallel corrugations of the upper surface. A dopant of a second, opposite conduction type is implanted to form a doped well region in the upper layer, and a dopant of the first conduction type is implanted into a portion of the corrugated surface adjacent to the gate, thereby forming a heavily doped source region in the upper layer. In an alternative procedure for forming a gate, a gate trench having a floor comprising parallel corrugations that substantially correspond to the corrugations in the upper surface is etched into the upper layer. Following lining of the trench floor and sidewalls with an insulating layer, the trench is substantially filled with a conductive material to form a gate trench. A dopant of the first conduction type is implanted into a portion of the corrugated surface adjacent to the gate region, thereby forming a heavily doped source region in the upper layer.