Abstract:
An insulated-gate field-effect transistor (100, 100V, 140, 150, 150V, 160, 170, 170V, 180, 180V, 190, 210, 210W, 220, 220U, 220V, 220W, 380, or 480) has a hypoabrupt vertical dopant profile below one (104 or 264) of its source/drain zones for reducing the parasitic capacitance along the pn junction between that source/drain zone and adjoining body material (108 or 268). In particular, the concentration of semiconductor dopant which defines the conductivity type of the body material increases by at least a factor of 10 in moving from that source/drain zone down to an underlying body-material location no more than 10 times deeper below the upper semiconductor surface than that source/drain zone. The body material preferably includes a more heavily doped pocket portion (120 or 280) situated along the other source/drain zone (102 or 262). The combination of the hypoabrupt vertical dopant profile below the first-mentioned source/drain zone, normally serving as the drain, and the pocket portion along the second-mentioned source/drain zone, normally serving as the source, enables the resultant asymmetric transistor to be especially suitable for high-speed analog applications.
Abstract:
A group of high-performance like-polarity insulated-gate field-effect transistors (100, 108, 112, 116, 120, and 124 or 102, 110, 114, 118, 122, and 126) have selectably different configurations of lateral source/drain extensions, halo pockets, and gate dielectric thicknesses suitable for a semiconductor fabrication platform that provides a wide variety of transistors for analog and/or digital applications. Each transistor has a pair of source/drain zones, a gate dielectric layer, and a gate electrode. Each source/drain zone includes a main portion and a more lightly doped lateral extension. The lateral extension of one of the source/drain zones of one of the transistors is more heavily doped or/and extends less deeply below the upper semiconductor surface than the lateral extension of one of the source/drain zones of another of the transistors.
Abstract:
An insulated-gate field-effect transistor (100W) has a source (980) and a drain (242) laterally separated by a channel zone (244) of body material (180) of a semiconductor body. A gate electrode (262) overlies a gate dielectric layer (260) above the channel zone. A more heavily doped pocket portion (250) of the body material normally extends largely along only the source so that the IGFET is an asymmetric device. The source has a main source portion (980M) and a more lightly doped lateral source extension (980E). The semiconductor dopant which defines the source reaches multiple local concentration maxima in defining the source extension. The procedure involved in defining the source extension with semiconductor dopant that reaches two such local concentration maxima enables source/drain extensions of mutually different characteristics for three insulated-gate field-effect transistors to be defined in only two source/drain-extension doping operations.
Abstract:
An insulated-gate field-effect transistor (100) provided along an upper surface of a semiconductor body contains a pair of source/drain zones (240 and 242) laterally separated by a channel zone (244). A gate electrode (262) overlies a gate dielectric layer (260) above the channel zone. Each source/drain zone includes a main portion (240M or 242M) and a more lightly doped lateral extension (240E or 242E) laterally continuous with the main portion and extending laterally under the gate electrode. The lateral extensions, which terminate the channel zone along the upper semiconductor surface, are respectively largely defined by a pair of semiconductor dopants of different atomic weights. With the transistor being an asymmetric device, the source/drain zones constitute a source and a drain. The lateral extension of the source is then more lightly doped than, and defined with dopant of higher atomic weight, than the lateral extension of the drain.
Abstract:
Each of a pair of like-polarity IGFETs (40 or 42 and 240 or 242) has a channel zone (64 or 84) situated in body material (50). Short-channel effects are alleviated by arranging for the net dopant concentration in the channel zone to longitudinally reach a local surface minimum at a location between the IGFET's source/drain zones (60 and 62 or 80 and 82) and by arranging for the net dopant concentration in the body material to reach a local subsurface maximum more than 0.1 μm deep into the body material but not more than 0.4 μm deep into the body material. A pocket portion (100/102 or 104) extends along both source drain zones of one of the IGFETs. A pocket portion (244 or 246) extends largely along only one of the source/drain zones of the other IGFET so that it is an asymmetrical device.
Abstract:
A semiconductor technology combines a normally off n-channel channel-junction insulated-gate field-effect transistor (“IGFET”) (104) and an n-channel surface-channel IGFET (100 or 160) to reduce low-frequency 1/f noise. The channel-junction IGFET is normally fabricated to be of materially greater gate dielectric thickness than the surface-channel IGFET so as to operate across a greater voltage range than the surface-channel IGFET. A p-channel surface-channel IGFET (102 or 162), which is typically fabricated to be of approximately the same gate-dielectric thickness as the n-channel surface-channel IGFET, is preferably combined with the two n-channel IGFETs to produce a complementary-IGFET structure. A further p-channel IGFET (106, 180, 184, or 192), which is typically fabricated to be of approximately the same gate dielectric thickness as the n-channel channel-junction IGFET, is also preferably included. The further p-channel IGFET can be a surface-channel or channel-junction device.
Abstract translation:半导体技术结合了正常n沟道沟道结绝缘栅场效应晶体管(“IGFET”)(104)和n沟道表面沟道IGFET(100或160),以降低低频1 / f 噪声。 沟道结IGFET通常被制造为具有比表面沟道IGFET大得多的栅介质厚度,以便在比表面沟道IGFET更大的电压范围内工作。 典型地制造为与n沟道表面沟道IGFET大致相同的栅介质厚度的p沟道表面沟道IGFET(102或162)优选地与两个n沟道IGFET组合以产生 互补IGFET结构。 还优选包括通常被制造为具有与n沟道沟道结IGFET大致相同的栅介质厚度的另外的p沟道IGFET(106,180,184或192)。 另外的p沟道IGFET可以是表面沟道或沟道结器件。
Abstract:
A semiconductor junction varactor utilizes gate enhancement for enabling the varactor to achieve a high ratio of maximum capacitance to minimum capacitance. The varactor has a gate region (131 or 181) divided into multiple portions of differing zero-point threshold voltages for enabling the varactor capacitance to vary relatively gradually with a control voltage applied to the varactor.
Abstract:
An insulated-gate field-effect transistor utilizes local threshold-adjust doping to control the voltage at which the transistor turns on. The local threshold-adjust doping is present along part, but not all, of the lateral extent of the channel. In the transistor structure, a channel zone laterally separates a pair of source/drain zones. The channel zone is formed with a main channel portion and a more heavily doped threshold channel portion that contains the local threshold-adjust doping. Gate dielectric material vertically separates the channel zone from an overlying gate electrode. The transistor is a long device in that the gate electrode is longer, preferably at least 50% longer, than the gate electrode of a minimum-sized transistor whose gate length is approximately the minimum feature size. The long-gate transistor is suitable for use in analog and high-voltage digital portions of a VLSI circuit.
Abstract:
An insulated gate semiconductor device contains a common drain and a plurality of cells, each having a body region and a source. In each cell, the body region contains a channel region extending between the common drain and the source. The body region further includes a special portion spaced apart from the channel region, more heavily doped than the portion of the body region below the source, extending no more than an electrically insignificant amount below the source, and not extending significantly deeper below the upper semiconductor surface than the portion of the body region underlying the source. The special portion of each body region provides improved ruggedness under drain avalanche conditions. The special portion of each body region normally reaches a peak net dopant concentration below the upper semiconductor surface. Instead of, or in addition to, having the special portion of each body region be subsurface-peaked, the portion of each body region below the source can extend deeper below the upper semiconductor surface than the portion of the body region underlying the special portion.
Abstract:
Power MOSFET apparatus, and method for its production, that suppresses voltage breakdown near the gate, using a polygon-shaped trench in which the gate is positioned, using a shaped deep body junction that partly lies below the trench bottom, and using special procedures for growth of gate oxide at various trench corners.