Abstract: A microelectronic device having an n-type buried layer (NBL) is formed by forming a thin screen layer on the top surface of the substrate. Antimony is implanted through the screen layer exposed by an implant mask into the substrate; the implant mask blocks antimony from the substrate outside the NBL area. The implant mask is removed, leaving the screen layer, which has the same thickness over the NBL area and the area outside the NBL, on the surface. Silicon dioxide is formed during an anneal/drive process, both in the NBL area and outside the NBL area. Slightly more silicon dioxide is formed in the NBL area, consuming more silicon there and so forming a shallow silicon recess. An epitaxial layer is grown on the top surface of the substrate. A structure for the microelectronic device is also disclosed.

Abstract: An integrated circuit which includes a field-plated FET is formed by forming a first opening in a layer of oxide mask, exposing an area for a drift region. Dopants are implanted into the substrate under the first opening. Subsequently, dielectric sidewalls are formed along a lateral boundary of the first opening. A field relief oxide is formed by thermal oxidation in the area of the first opening exposed by the dielectric sidewalls. The implanted dopants are diffused into the substrate to form the drift region, extending laterally past the layer of field relief oxide. The dielectric sidewalls and layer of oxide mask are removed after the layer of field relief oxide is formed. A gate is formed over a body of the field-plated FET and over the adjacent drift region. A field plate is formed immediately over the field relief oxide adjacent to the gate.

Abstract: An ESD cell includes an n+ buried layer (NBL) within a p-epi layer on a substrate. An outer deep trench isolation ring (outer DT ring) includes dielectric sidewalls having a deep n-type diffusion (DEEPN diffusion) ring (DEEPN ring) contacting the dielectric sidewall extending downward to the NBL. The DEEPN ring defines an enclosed p-epi region. A plurality of inner DT structures are within the enclosed p-epi region having dielectric sidewalls and DEEPN diffusions contacting the dielectric sidewalls extending downward from the topside surface to the NBL. The inner DT structures have a sufficiently small spacing with one another so that adjacent DEEPN diffusion regions overlap to form continuous wall of n-type material extending from a first side to a second side of the outer DT ring dividing the enclosed p-epi region into a first and second p-epi region. The first and second p-epi region are connected by the NBL.

Abstract: A laterally diffused metal oxide semiconductor (LDMOS) device includes a substrate having a p-epi layer thereon, a p-body region in the p-epi layer and an ndrift (NDRIFT) region within the p-body to provide a drain extension region. A gate stack includes a gate dielectric layer over a channel region in the p-body region adjacent to and on respective sides of a junction with the NDRIFT region. A patterned gate electrode is on the gate dielectric. A DWELL region is within the p-body region. A source region is within the DWELL region, and a drain region is within the NDRIFT region. An effective channel length (Leff) for the LDMOS device is 75 nm to 150 nm which evidences a DWELL implant that utilized an edge of the gate electrode to delineate an edge of a DWELL ion implant so that the DWELL region is self-aligned to the gate electrode.

Abstract: A method for forming trench capacitors includes forming a silicon nitride layer over a first region of a semiconductor surface doped a first type and over a second region doped a second type. A patterned photoresist layer is directly formed on the silicon nitride layer. An etch forms a plurality of deep trenches (DTs) within the first region. A liner oxide is formed that lines the DTs. The silicon nitride layer is etched forming an opening through the silicon nitride layer that is at least as large in area as the area of an opening in the semiconductor surface of the DT below the silicon nitride layer. The liner oxide is removed, a dielectric layer(s) on a surface of the DTs is formed, a top plate material layer is deposited to fill the DTs, and the top plate material layer is removed beyond the DT to form a top plate.

Abstract: An ESD cell includes an n+ buried layer (NBL) within a p-epi layer on a substrate. An outer deep trench isolation ring (outer DT ring) includes dielectric sidewalls having a deep n-type diffusion (DEEPN diffusion) ring (DEEPN ring) contacting the dielectric sidewall extending downward to the NBL. The DEEPN ring defines an enclosed p-epi region. A plurality of inner DT structures are within the enclosed p-epi region having dielectric sidewalls and DEEPN diffusions contacting the dielectric sidewalls extending downward from the topside surface to the NBL. The inner DT structures have a sufficiently small spacing with one another so that adjacent DEEPN diffusion regions overlap to form continuous wall of n-type material extending from a first side to a second side of the outer DT ring dividing the enclosed p-epi region into a first and second p-epi region. The first and second p-epi region are connected by the NBL.

Abstract: A deep trench capacitor and a method for providing the same in a semiconductor process are disclosed. The method includes forming a plurality of deep trenches in a first region of a semiconductor wafer, the first region having well doping of a first type. A dielectric layer is formed on a surface of the plurality of deep trenches and a doped polysilicon layer is deposited to fill the plurality of deep trenches, with the doped polysilicon being doped with a dopant of a second type. Shallow trench isolation is formed overlying the dielectric layer at an intersection of the dielectric layer with the surface of the semiconductor wafer.

Abstract: An integrated trench capacitor and method for making the trench capacitor is disclosed. The method includes forming a trench in a silicon layer, forming a first dielectric on the exposed surface of the trench, performing an anisotropic etch of the first dielectric to expose silicon at the bottom of the trench, implanting a dopant into exposed silicon at the bottom of the trench, forming a first polysilicon layer over the first dielectric, forming a second dielectric over the first polysilicon layer, and forming a second polysilicon layer over the second dielectric to fill the trench.

Abstract: A semiconductor device adopts an isolation scheme to protect low voltage transistors from high voltage operations. The semiconductor device includes a substrate, a buried layer, a transistor well region, a first trench, and a second trench. The substrate has a top surface and a bottom surface. The buried layer is positioned within the substrate, and the transistor well region is positioned above the buried layer. The first trench extends from the top surface to penetrate the buried layer, and the first trench has a first trench depth. The second trench extending from the top surface to penetrate the buried layer. The second trench is interposed between the first trench and the transistor well region. The second trench has a second trench depth that is less than the first trench depth.

Abstract: A laterally diffused metal oxide semiconductor (LDMOS) device includes a substrate having a p-epi layer thereon, a p-body region in the p-epi layer and an ndrift (NDRIFT) region within the p-body to provide a drain extension region. A gate stack includes a gate dielectric layer over a channel region in the p-body region adjacent to and on respective sides of a junction with the NDRIFT region. A patterned gate electrode is on the gate dielectric. A DWELL region is within the p-body region. A source region is within the DWELL region, and a drain region is within the NDRIFT region. An effective channel length (Leff) for the LDMOS device is 75 nm to 150 nm which evidences a DWELL implant that utilized an edge of the gate electrode to delineate an edge of a DWELL ion implant so that the DWELL region is self-aligned to the gate electrode.

Abstract: A semiconductor device is formed by forming a deep trench in a substrate and a dielectric liner on sidewalls of the deep trench. A first undoped polysilicon layer is formed on the semiconductor device, extending into the deep trench on the dielectric liner, but not filling the deep trench. Dopants are implanted into the first polysilicon layer. A second layer of polysilicon is formed on the first layer of polysilicon. A thermal drive anneal activates and diffuses the dopants. In one version, the dielectric liner is removed at the bottom of the deep trench before the first polysilicon layer is formed, so that the polysilicon in the deep trench provides a contact to the substrate. In another version, the polysilicon in the deep trench is isolated from the substrate by the dielectric liner.

Abstract: An integrated circuit containing a first plurality of MOS transistors operating in a low voltage range, and a second plurality of MOS transistors operating in a mid voltage range, may also include a high-voltage MOS transistor which operates in a third voltage range significantly higher than the low and mid voltage ranges, for example 20 to 30 volts. The high-voltage MOS transistor has a closed loop configuration, in which a drain region is surrounded by a gate, which is in turn surrounded by a source region, so that the gate does not overlap field oxide. The integrated circuit may include an n-channel version of the high-voltage MOS transistor and/or a p-channel version of the high-voltage MOS transistor. Implanted regions of the n-channel version and the p-channel version are formed concurrently with implanted regions in the first and second pluralities of MOS transistors.

Abstract: A semiconductor device adopts an isolation scheme to protect low voltage transistors from high voltage operations. The semiconductor device includes a substrate, a buried layer, a transistor well region, a first trench, and a second trench. The substrate has a top surface and a bottom surface. The buried layer is positioned within the substrate, and the transistor well region is positioned above the buried layer. The first trench extends from the top surface to penetrate the buried layer, and the first trench has a first trench depth. The second trench extending from the top surface to penetrate the buried layer. The second trench is interposed between the first trench and the transistor well region. The second trench has a second trench depth that is less than the first trench depth.

Abstract: An integrated circuit containing a first plurality of MOS transistors operating in a low voltage range, and a second plurality of MOS transistors operating in a mid voltage range, may also include a high-voltage MOS transistor which operates in a third voltage range significantly higher than the low and mid voltage ranges, for example 20 to 30 volts. The high-voltage MOS transistor has a closed loop configuration, in which a drain region is surrounded by a gate, which is in turn surrounded by a source region, so that the gate does not overlap field oxide. The integrated circuit may include an n-channel version of the high-voltage MOS transistor and/or a p-channel version of the high-voltage MOS transistor. Implanted regions of the n-channel version and the p-channel version are formed concurrently with implanted regions in the first and second pluralities of MOS transistors.

Abstract: A method of fabricating an integrated circuit (IC) includes etching a trench in a semiconductor layer on a substrate having an aspect ratio (AR)?5 and a trench depth?10 ?m. A dielectric liner is formed along the walls of the trench. An in-situ doped polysilicon layer having a first thickness is deposited into the trench to form a dielectric lined partially filled trench. An un-doped polysilicon layer having a second thickness greater than the first thickness is deposited on the in-situ doped polysilicon layer to complete a filling of the trench to provide a polysilicon filled trench. The doped polysilicon filler after completion of fabricating the IC is essentially polysilicon void-free and has a 25° C. sheet resistance?60 ohms/sq. The method can include etching an opening at a bottom of the dielectric liner before depositing the polysilicon to provide ohmic contact to the semiconductor layer.

Abstract: An integrated circuit which includes a field-plated FET is formed by forming a first opening in a layer of oxide mask, exposing an area for a drift region. Dopants are implanted into the substrate under the first opening. Subsequently, dielectric sidewalls are formed along a lateral boundary of the first opening. A field relief oxide is formed by thermal oxidation in the area of the first opening exposed by the dielectric sidewalls. The implanted dopants are diffused into the substrate to form the drift region, extending laterally past the layer of field relief oxide. The dielectric sidewalls and layer of oxide mask are removed after the layer of field relief oxide is formed. A gate is formed over a body of the field-plated FET and over the adjacent drift region. A field plate is formed immediately over the field relief oxide adjacent to the gate.

Abstract: An integrated circuit which includes a field-plated FET is formed by forming a first opening in a layer of oxide mask, exposing an area for a drift region. Dopants are implanted into the substrate under the first opening. Subsequently, dielectric sidewalls are formed along a lateral boundary of the first opening. A field relief oxide is formed by thermal oxidation in the area of the first opening exposed by the dielectric sidewalls. The implanted dopants are diffused into the substrate to form the drift region, extending laterally past the layer of field relief oxide. The dielectric sidewalls and layer of oxide mask are removed after the layer of field relief oxide is formed. A gate is formed over a body of the field-plated FET and over the adjacent drift region. A field plate is formed immediately over the field relief oxide adjacent to the gate.

Abstract: A laterally diffused metal oxide semiconductor (LDMOS) device includes a substrate having a p-epi layer thereon, a p-body region in the p-epi layer and an ndrift (NDRIFT) region within the p-body to provide a drain extension region. A gate stack includes a gate dielectric layer over a channel region in the p-body region adjacent to and on respective sides of a junction with the NDRIFT region. A patterned gate electrode is on the gate dielectric. A DWELL region is within the p-body region. A source region is within the DWELL region, and a drain region is within the NDRIFT region. An effective channel length (Leff) for the LDMOS device is 75 nm to 150 nm which evidences a DWELL implant that utilized an edge of the gate electrode to delineate an edge of a DWELL ion implant so that the DWELL region is self-aligned to the gate electrode.

Abstract: A semiconductor device has an n-type buried layer formed by implanting antimony and/or arsenic into the p-type first epitaxial layer at a high dose and low energy, and implanting phosphorus at a low dose and high energy. A thermal drive process diffuses and activates both the heavy dopants and the phosphorus. The antimony and arsenic do not diffuse significantly, maintaining a narrow profile for a main layer of the buried layer. The phosphorus diffuses to provide a lightly-doped layer several microns thick below the main layer. An epitaxial p-type layer is grown over the buried layer.

Abstract: A semiconductor device is formed by forming a deep trench in a substrate and a dielectric liner on sidewalls of the deep trench. A first undoped polysilicon layer is formed on the semiconductor device, extending into the deep trench on the dielectric liner, but not filling the deep trench. Dopants are implanted into the first polysilicon layer. A second layer of polysilicon is formed on the first layer of polysilicon. A thermal drive anneal activates and diffuses the dopants. In one version, the dielectric liner is removed at the bottom of the deep trench before the first polysilicon layer is formed, so that the polysilicon in the deep trench provides a contact to the substrate. In another version, the polysilicon in the deep trench is isolated from the substrate by the dielectric liner.