Abstract: A lateral-diffused-metal-oxide-semiconductor device having improved safe-operating-area is provided. The LDMOS device includes spaced-apart source and drain, separated by a first insulated gate structure, and spaced-apart source and body contact The spaced-apart source and BC are part of the emitter-base circuit of a parasitic bipolar transistor that can turn on prematurely, thereby degrading the SOA of prior art four-terminal LDMOS devices. Rather than separating the source and BC with a shallow-trench-isolation region as in the prior art, the semiconductor surface in the gap between the spaced-apart source and BC has there-over a second insulated gate structure, with its gate conductor electrically tied to the BC. When biased, the second insulated gate structure couples the source and BC lowering the parasitic resistance in the emitter-base circuit, thereby delaying turn-on of the parasitic transistor and improving the SOA of such 4-T LDMOS devices.

Abstract: A higher breakdown voltage transistor has separated emitter, base contact, and collector contact. Underlying the emitter and the base contact are, respectively, first and second base portions of a first conductivity type. Underlying and coupled to the collector contact is a collector region of a second, opposite, conductivity type, having a central portion extending laterally toward, underneath, or beyond the base contact and separated therefrom by the second base portion. A floating collector region of the same conductivity type as the collector region underlies and is separated from the emitter by the first base portion. The collector and floating collector regions are separated by a part of the semiconductor (SC) region in which the base is formed. A further part of the SC region in which the base is formed, laterally bounds or encloses the collector region.

Abstract: A multi-region (81, 83) lateral-diffused-metal-oxide-semiconductor (LDMOS) device (40) has a semiconductor-on-insulator (SOI) support structure (21) on or over which are formed a substantially symmetrical, laterally internal, first LDMOS region (81) and a substantially asymmetric, laterally edge-proximate, second LDMOS region (83). A deep-trench isolation (DTI) wall (60) substantially laterally terminates the laterally edge-proximate second LDMOS region (83). Electric field enhancement and lower source-drain breakdown voltages (BVDSS) exhibited by the laterally edge-proximate second LDMOS region (83) associated with the DTI wall (60) are avoided by providing a doped SC buried layer region (86) in the SOI support structure (21) proximate the DTI wall (60), underlying a portion of the laterally edge-proximate second LDMOS region (83) and of opposite conductivity type than a drain region (31) of the laterally edge-proximate second LDMOS region (83).

Abstract: A method of fabricating a reduced surface field (RESURF) transistor includes forming a first well in a substrate, the first well having a first conductivity type, doping a RESURF region of the first well to have a second conductivity type, doping a portion of the first well to form a drain region of the RESURF transistor, the drain region having the first conductivity type, and forming a second well in the substrate, the second well having the second conductivity type. A plug region is formed in the substrate, the plug region extending to the RESURF region.

Abstract: A device includes a semiconductor substrate, source and drain regions in the semiconductor substrate, a channel region in the semiconductor substrate between the source and drain regions through which charge carriers flow during operation from the source region to the drain region, and a drift region in the semiconductor substrate, on which the drain region is disposed, and through which the charge carriers drift under an electric field arising from application of a bias voltage between the source and drain regions. A PN junction along the drift region includes a first section at the drain region and a second section not at the drain region. The drift region has a lateral profile that varies such that the first section of the PN junction is shallower than the second section of the PN junction.

Abstract: Adverse tradeoff between BVDSS and Rdson in LDMOS devices employing a drift space (52, 152) adjacent the drain (56, 156), is avoided by providing a lightly doped region (511, 1511) of a first conductivity type (CT) separating the first CT drift space (52, 152) from an opposite CT WELL region (53, 153) in which the first CT source (57, 157) is located, and a further region (60, 160) of the opposite CT (e.g., formed by an angled implant) extending through part of the WELL region (53, 153) under an edge (591, 1591) of the gate (59, 159) located near a boundary (531, 1531) of the WELL region (53, 153) into the lightly doped region (511, 1511), and a shallow still further region (66, 166) of the first CT Ohmically coupled to the source (57, 157) and ending near the gate edge (591, 159) whereby the effective channel length (61, 161) in the further region (60, 160) is reduced to near zero.

Abstract: Metal-insulator metal (MIM) capacitors are formed by providing a substrate having a first surface, forming thereon a first electrode having conductive and insulating regions wherein the conductive regions desirably have an area density DA less than 100%. A first dielectric is formed over the first electrode. A cavity is formed in the first dielectric, having a sidewall extending to the first electrode and exposing thereon some of the first electrode conductive and insulating regions. An electrically conductive barrier layer is formed covering the sidewall and the some of the first electrode conductive and insulating regions. A capacitor dielectric layer is formed in the cavity covering the barrier layer. A counter electrode is formed in the cavity covering the capacitor dielectric layer. External connections are formed to a portion of the first electrode laterally outside the cavity and to the counter electrode within the cavity.

Abstract: Insufficient gain in bipolar transistors (20) is improved by providing an alloyed (e.g., silicided) emitter contact (452) smaller than the overall emitter (42) area. The improved emitter (42) has a first emitter (FE) portion (42-1) of a first dopant concentration CFE, and a second emitter (SE) portion (42-2) of a second dopant concentration CSE. Preferably CSE?CFE. The SE portion (42-2) desirably comprises multiple sub-regions (45i, 45j, 45k) mixed with multiple sub-regions (47m, 47n, 47p) of the FE portion (42-1). A semiconductor-metal alloy or compound (e.g., a silicide) is desirably used for Ohmic contact (452) to the SE portion (42-2) but substantially not to the FE portion (42-1). Including the FE portion (42-1) electrically coupled to the SE portion (42-2) but not substantially contacting the emitter contact (452) on the SE portion (42-2) provides gain increases of as much as ˜278.

Abstract: A device includes a semiconductor substrate including a surface, a drain region in the semiconductor substrate having a first conductivity type, a well region in the semiconductor substrate on which the drain region is disposed, the well region having the first conductivity type, a buried isolation layer in the semiconductor substrate extending across the well region, the buried isolation layer having the first conductivity type, a reduced surface field (RESURF) region disposed between the well region and the buried isolation layer, the RESURF region having a second conductivity type, and a plug region in the semiconductor substrate extending from the surface of the substrate to the RESURF region, the plug region having the second conductivity type.

Abstract: A device includes a semiconductor substrate, a channel region in the semiconductor substrate having a first conductivity type, and a composite drift region in the semiconductor substrate, having a second conductivity type. The composite drift region includes a first drift region and a second drift region spaced from the channel region by the first drift region. The device further includes a drain region in the semiconductor substrate, spaced from the channel region by the composite drain region, and having the second conductivity type. The first drift region has a dopant concentration profile with a first concentration level where adjacent the channel region and a second concentration level where adjacent the second drift region, the first concentration level being higher than the second concentration level. In some embodiments, the first and second drift regions are stacked vertically, with the first drift region being shallower than the second drift region.

Abstract: A capacitor suitable for inclusion in a semiconductor device includes a substrate, a first metallization level, a capacitor dielectric, a capacitor plate, an interlevel dielectric layer, and a second metallization level. The first metallization level overlies the substrate and includes a first metallization plate overlying a capacitor region of the substrate. The capacitor dielectric overlies the first metallization plate and includes a dielectric material such as a silicon oxide or silicon nitride compound. The capacitor plate is an electrically conductive structure that overlies the capacitor dielectric. The interlevel dielectric overlies the capacitor plate. The second metallization layer overlies the interlevel dielectric layer and may include a second metallization plate and a routing element. The routing element may be electrically connected to the capacitor plate. The metallization plates may include a fingered structure that includes a plurality of elongated elements extending from a cross bar.

Abstract: A disclosed power transistor, suitable for use in a switch mode converter that is operable with a switching frequency exceeding, for example, 5 MHz or more, includes a gate dielectric layer overlying an upper surface of a semiconductor substrate and first and second gate electrodes overlying the gate dielectric layer. The first gate electrode is laterally positioned overlying a first region of the substrate. The first substrate region has a first type of doping, which may be either n-type or p-type. A second gate electrode of the power transistor overlies the gate dielectric and is laterally positioned over a second region of the substrate. The second substrate region has a second doping type that is different than the first type. The transistor further includes a drift region located within the substrate in close proximity to an upper surface of the substrate and laterally positioned between the first and second substrate regions.

Abstract: A semiconductor device includes an isolated p-type well, wherein the isolated p-type well is a first electrode of a capacitor device; a capacitor dielectric on the isolated p-type well; a p-type polysilicon electrode over the capacitor dielectric, wherein the p-type polysilicon electrode is a second electrode of the capacitor device; a first p-type contact region in the isolated p-type well, laterally extending from a first sidewall of the p-type polysilicon electrode; a second p-type contact region in the isolated p-type well, laterally extending from a second sidewall of the p-type polysilicon electrode, opposite the first sidewall of the p-type polysilicon electrode, wherein a portion of the isolated p-type well between the first and second p-type contact regions is under the p-type polysilicon electrode and the capacitor dielectric; and an n-type isolation region surrounding the isolated p-type well. This device may be conveniently coupled to a fringe capacitor.

Abstract: Breakdown voltage BVdss is enhanced and ON-resistance reduced in RESURF devices, e.g., LDMOS transistors, by careful charge balancing, even when body and drift region charge balance is not ideal, by: (i) providing a plug or sinker near the drain and of the same conductivity type extending through the drift region at least into the underlying body region, and/or (ii) applying bias Viso to a surrounding lateral doped isolation wall coupled to the device buried layer, and/or (iii) providing a variable resistance bridge between the isolation wall and the drift region. The bridge may be a FET whose source-drain couple the isolation wall and drift region and whose gate receives control voltage Vc, or a resistor whose cross-section (X, Y, Z) affects its resistance and pinch-off, to set the percentage of drain voltage coupled to the buried layer via the isolation wall.

Abstract: Insufficient gain in bipolar transistors (20) is improved by providing an alloyed (e.g., silicided) emitter contact (452) smaller than the overall emitter (42) area. The improved emitter (42) has a first emitter (FE) portion (42-1) of a first dopant concentration CFE, and a second emitter (SE) portion (42-2) of a second dopant concentration CSE. Preferably CSE?CFE. The SE portion (42-2) desirably comprises multiple sub-regions (45i, 45j, 45k) mixed with multiple sub-regions (47m, 47n, 47p) of the FE portion (42-1). A semiconductor-metal alloy or compound (e.g., a silicide) is desirably used for Ohmic contact (452) to the SE portion (42-2) but substantially not to the FE portion (42-1). Including the FE portion (42-1) electrically coupled to the SE portion (42-2) but not substantially contacting the emitter contact (452) on the SE portion (42-2) provides gain increases of as much as ˜278.

Abstract: A device includes a semiconductor substrate including a surface, a drain region in the semiconductor substrate having a first conductivity type, a well region in the semiconductor substrate on which the drain region is disposed, the well region having the first conductivity type, a buried isolation layer in the semiconductor substrate extending across the well region, the buried isolation layer having the first conductivity type, a reduced surface field (RESURF) region disposed between the well region and the buried isolation layer, the RESURF region having a second conductivity type, and a plug region in the semiconductor substrate extending from the surface of the substrate to the RESURF region, the plug region having the second conductivity type.

Abstract: Breakdown voltage BVdss is enhanced and ON-resistance reduced in RESURF devices (40, 60, 80, 80?, 80?), e.g., LDMOS transistors, by careful charge balancing, even when body (44, 44?, 84, 84?) and drift (50, 50?, 90, 90?) region charge balance is not ideal, by: (i) providing a plug or sinker (57) near the drain (52, 92) and of the same conductivity type extending through the drift region (50, 50?, 90, 90?) at least into the underlying body region (44, 44? 84, 84?), and/or (ii) applying bias Viso to a surrounding lateral doped isolation wall (102) coupled to the device buried layer (42, 82), and/or (iii) providing a variable resistance bridge (104) between the isolation wall (102) and the drift region (50, 50?, 90, 90?).

Abstract: Insufficient gain in bipolar transistors (20) is improved by providing an alloyed (e.g., silicided) emitter contact (452) smaller than the overall emitter (42) area. The improved emitter (42) has a first emitter (FE) portion (42-1) of a first dopant concentration CFE, and a second emitter (SE) portion (42-2) of a second dopant concentration CSE. Preferably CSE?CFE. The SE portion (42-2) desirably comprises multiple sub-regions (45i, 45j, 45k) mixed with multiple sub-regions (47m, 47n, 47p) of the FE portion (42-1). A semiconductor-metal alloy or compound (e.g., a silicide) is desirably used for Ohmic contact (452) to the SE portion (42-2) but substantially not to the FE portion (42-1). Including the FE portion (42-1) electrically coupled to the SE portion (42-2) but not substantially contacting the emitter contact (452) on the SE portion (42-2) provides gain increases of as much as ˜278.

Abstract: By providing a novel bipolar device design implementation, a standard CMOS process can be used unchanged to fabricate useful bipolar transistors and other bipolar devices having adjustable properties by partially blocking the P or N well doping used for the transistor base. This provides a hump-shaped base region with an adjustable base width, thereby achieving, for example, higher gain than can be obtained with the unmodified CMOS process alone. By further partially blocking the source/drain doping step used to form the emitter of the bipolar transistor, the emitter shape and effective base width can be further varied to provide additional control over the bipolar device properties. The embodiments thus include prescribed modifications to the masks associated with the bipolar device that are configured to obtain desired device properties. The CMOS process steps and flow are otherwise unaltered and no additional process steps are required.

Abstract: Methods are disclosed for forming an antifuse that includes first and second conductive regions having spaced-apart curved portions, with a first dielectric region therebetween, forming in combination with the curved portions a curved breakdown region adapted to switch from a substantially non-conductive initial state to a substantially conductive final state in response to a predetermined programming voltage. A sense voltage less than the programming voltage is used to determine the state of the antifuse as either OFF (high impedance) or ON (low impedance). A shallow trench isolation (STI) region is desirably provided adjacent the breakdown region to inhibit heat loss from the breakdown region during programming. Lower programming voltages and currents are observed compared to antifuses using substantially planar dielectric regions. In a further embodiment, a resistive region is inserted in one lead of the antifuse with either planar or curved breakdown regions to improve post-programming sense reliability.