Abstract: A method of verifying consistency between a circuit schematic and a corresponding integrated circuit layout is disclosed. The method includes identifying a voltage condition associated with a portion of the circuit schematic, and assigning a pseudo diode to the portion of the circuit schematic that is uniquely associated with the identified voltage condition. The method further includes coding a pseudo layer associated with an integrated circuit layout of the circuit schematic in accordance with content of the assigned pseudo diode, and verifying consistency between the circuit schematic and the corresponding integrated circuit layout by extracting the pseudo layer from the integrated circuit layout and comparing information of the pseudo layer to the assigned pseudo diode in the circuit schematic.

Abstract: A semiconductor device is obtained, in which excellent characteristics are achieved, the reliability is improved, and an SiC wafer can also be used for the fabrication. A plurality of Schottky-barrier-diode units 10 is formed on an SiC chip 9, and each of the units 10 has an external output electrode 4 independently of each other. Bumps 11 (the diameter is from several tens to several hundreds of ?m) are formed only on the external output electrodes 4 of non-defective units among the units 10 formed on the SiC chip 9, meanwhile bumps are not formed on the external output electrodes 4 of defective units in which the withstand voltage is too low, or the leakage current is too much.

Abstract: A semiconductor device includes: a nitride semiconductor layer including a channel layer, a Schottky electrode that contacts the nitride semiconductor layer and contains indium, and an ohmic electrode that contacts the channel layer. The nitride semiconductor layer includes a layer that contacts the Schottky electrode and contains AlGaN, InAlGaN or GaN. The Schottky electrode that contains indium includes one of an indium oxide layer and an indium tin oxide layer.

Abstract: A method manufactures a vertical power MOS transistor on a semiconductor substrate comprising a first superficial semiconductor layer of a first conductivity type, comprising: forming trench regions in the first semiconductor layer, filling in said trench regions with a second semiconductor layer of a second conductivity type, to form semiconductor portions of the second conductivity type contained in the first semiconductor layer, carrying out an ion implantation of a first dopant type in the semiconductor portions for forming respective implanted body regions of said second conductivity type, carrying out an ion implantation of a second dopant type in one of the implanted body regions for forming an implanted source region of the first conductivity type inside one of the body regions, carrying out an activation thermal process of the first and second dopant types with low thermal budget suitable to complete said formation of the body and source regions.

Abstract: An anti-parallel diode structure and method of fabrication is presently disclosed. In some embodiments, an anti-parallel diode structure has a semiconductor region comprising a first insulator layer disposed between a first semiconductor layer and a second semiconductor layer. The semiconductor region can be bound on a first side by a first metal material and bound on a second side by a second metal material so that current below a predetermined value is prevented from passing through the semiconductor region and current above the predetermined value passes through the semiconductor region.

Abstract: A gallium nitride based semiconductor Schottky diode fabricated from a n+ doped GaN layer having a thickness between one and six microns disposed on a sapphire substrate; an n? doped GaN layer having a thickness greater than one micron disposed on said n+ GaN layer patterned into a plurality of elongated fingers and a metal layer disposed on the n? doped GaN layer and forming a Schottky junction therewith. The layer thicknesses and the length and width of the elongated fingers are optimized to achieve a device with breakdown voltage of greater than 500 volts, current capacity in excess of one ampere, and a forward voltage of less than three volts.

Abstract: A gate electrode is formed overlying a substrate. A first angled metal implant is performed at a first angle into the substrate followed by performing a second angled metal implant at a second angle. The first angled metal implant and the second angled metal implant form a first current electrode and a second current electrode. Each of the first current electrode and the second current electrode has at least two regions of differing metal composition. A metal layer is deposited overlying the gate electrode, the first current electrode and the second current electrode. The metal layer is annealed to form two Schottky junctions in each of the first current electrode and the second current electrode. The two Schottky junctions have differing barrier levels.

Abstract: Disclosed are semiconductor devices and methods of making semiconductor devices. An exemplary embodiment comprises a semiconductor layer of a first conductivity type having a first surface, a second surface, and a graded net doping concentration of the first conductivity type within a portion of the semiconductor layer. The graded portion is located adjacent to the top surface of the semiconductor layer, and the graded net doping concentration therein decreasing in value with distance from the top surface of the semiconductor layer. The exemplary device also comprises an electrode disposed at the first surface of the semiconductor layer and adjacent to the graded portion.

Abstract: In the diffusion region (3) of the second conductivity mode, a more highly doped region of the same conductivity mode (5) is introduced in such a manner that the region of the first conductivity mode (2) which is covered by the metal silicide (9) and of the second conductivity mode (3) are connected in a conductive manner. The region (3) of the second conductivity mode is diffused in such a manner that it reaches the more highly doped region (1) of the first doping type (1), with an outward diffusion of the doping from the more highly doped substrate layer (1) into the more weakly doped layer (2) of the same conductivity mode in the direction of the semiconductor surface taking place at the same time.

Abstract: A lateral passive device is disclosed including a dual annular electrode. The annular electrodes form an anode and a cathode. The annular electrodes allow anode and cathode series resistances to be optimized to the lowest values at a fixed device area. In addition, the parasitic capacitance to a bottom plate (substrate) is greatly reduced. In one embodiment, a device includes a first annular electrode surrounding a second annular electrode formed on a substrate, and the second annular electrode surrounds an insulator region. A related method is also disclosed.

Abstract: A Schottky diode capable of sustaining a voltage of greater than about 250 volts and a method for its manufacture. An epitaxial layer of N-type conductivity is disposed on a semiconductor substrate of N-type conductivity. A guard ring of P-type conductivity extends into the epitaxial layer from its surface. A stacked structure is formed on a portion of the guard ring and a portion of the epitaxial layer. The stacked structure includes a layer of semi-insulating semiconductor material disposed on a layer of dielectric material. A first metal layer is formed on the portion of the epitaxial layer adjacent a first side of the stacked structure and on a first portion of the stacked structure. A second metal layer is formed on the portion of the epitaxial layer adjacent a second side of the stacked structure and on a second portion of the stacked structure.

Abstract: A semiconductor device (10) comprises a substrate (11), a semiconductor layer (12), an insulation film (13), a protective film (15), a source electrode (21), a drain electrode (22), a gate electrode (23). The semiconductor device (10) comprises a protective film (15) formed so as to cover at least an upper surface of the insulation film (13). This enables preventing aluminum contained in the source electrode (21) and the drain electrode (22) from reacting with material contained in the insulation film (13). Accordingly, the increase of the resistance of the electrode and the increase of current collapse are prevented. Accordingly, the semiconductor device (10) has a satisfactory electric performance characteristics.

Abstract: A high-voltage Schottky diode including a deep P-well having a first width is formed on the semiconductor substrate. A doped P-well is disposed over the deep P-well and has a second width that is less than the width of the deep P-well. An M-type guard ring is formed around the upper surface of the second doped well, A Schottky metal is disposed on an upper surface of the second doped well and the N-type guard ring.

Abstract: A Schottky barrier diode includes an epitaxial growth layer disposed on a substrate and having a mesa portion, and a Schottky electrode disposed on the mesa portion, wherein a distance between an edge of the Schottky electrode and a top surface edge of the mesa portion is 2 ?m or less. Since the distance x is 2 ?m or less, a leakage current is significantly decreased, a breakdown voltage is improved, and a Schottky barrier diode having excellent reverse breakdown voltage characteristics is provide.

Abstract: An integrated circuit structure includes a semiconductor substrate; a well region of a first conductivity type over the semiconductor substrate; a metal-containing layer on the well region, wherein the metal-containing layer and the well region form a Schottky barrier; an isolation region encircling the metal-containing layer; and a deep-well region of a second conductivity type opposite the first conductivity type under the metal-containing layer. The deep-well region has at least a portion vertically overlapping a portion of the metal-containing layer. The deep-well region is vertically spaced apart from the isolation region and the metal-containing layer by the well region.

Abstract: The gate oxide in the trenches of a trench type Schottky device are formed by oxidizing a layer of polysilicon deposited in trenches of a silicon or silicon carbide substrate. A small amount of the substrate is also oxidized to create a good interface between the substrate and the oxide layer which is formed. The corners of the trench are rounded by the initial formation and removal of a sacrificial oxide layer.

Abstract: Provided is a method for fabricating a Schottky barrier tunnel transistor (SBTT) that can fundamentally prevent the generation of a gate leakage current caused by damage of spacers formed on both sidewalls of a gate electrode. The method for fabricating a Schottky barrier tunnel transistor, which includes: a) forming a silicon pattern and a sacrificial pattern on a buried oxide layer supported by a support substrate; b) forming a source/drain region on the buried oxide layer exposed on both sides of the silicon pattern, the source/drain region being formed of a metal layer and being in contact with both sidewalls of the silicon pattern; c) removing the sacrificial pattern to expose the top surface of the silicon pattern; and d) forming a gate insulating layer and a gate electrode on the exposed silicon pattern.

Abstract: A semiconductor device provided with a silicon carbide semiconductor substrate, and an ohmic metal layer joined to one surface of the silicon carbide semiconductor substrate in an ohmic contact and composed of a metal material whose silicide formation free energy and carbide formation free energy respectively take negative values. The ohmic metal layer is composed of, for example, a metal material such as molybdenum, titanium, chromium, manganese, zirconium, tantalum, or tungsten.

Abstract: A monolithically integrated trench FET and Schottky diode includes a plurality of trenches extending into a FET region and a Schottky region of a semiconductor layer. A trench in the Schottky region includes a dielectric layer lining the trench sidewalls, and a conductive electrode having a top surface that is substantially coplanar with a top surface of the semiconductor layer adjacent the trench. An interconnect layer electrically contacts the semiconductor layer in the Schottky region so as to form a Schottky contact with the semiconductor layer.

Abstract: An electrical generator includes a substrate, a semiconductor piezoelectric structure having a first end and an opposite second end disposed adjacent to the substrate, a first conductive contact and a second conductive contact. The structure bends when a force is applied adjacent to the first end, thereby causing an electrical potential difference to exist between a first side and a second side of the structure. The first conductive contact is in electrical communication with the first end and includes a material that creates a Schottky barrier between a portion of the first end of the structure and the first conductive contact. The first conductive contact is also disposed relative to the structure in a position so that the Schottky barrier is forward biased when the structure is deformed, thereby allowing current to flow from the first conductive contact into the first end.

Abstract: A method for manufacturing electronic devices on a semiconductor substrate with wide band gap that includes the steps of: forming a screening structure on the semiconductor substrate to include at least a dielectric layer that leaves a plurality of areas of the semiconductor substrate exposed, carrying out at least a ion implantation of a first type of dopant in the semiconductor substrate to form at least a first implanted region, carrying out at least a ion implantation of a second type of dopant in the semiconductor substrate to form at least a second implanted region inside the at least a first implanted region, carrying out an activation thermal process of the first type and second type of dopant with low thermal temperature suitable to complete the formation of the at least first and second implanted regions without diffusing the at least first and at least second type dopants in the substrate.

Abstract: A method for fabrication and a structure of a self-aligned (crosspoint) memory device comprises lines (wires) in a first direction and in a second direction. The wires in the first direction are formed using a hard mask material that is resistant to the pre-selected etch processes used for creation of the lines in both the first and the second direction. Consequently, the hard mask material for the lines in the first direction form part of the memory stack.

Abstract: A semiconductor component having a low resistance conduction path and a method for manufacturing the semiconductor component. When the semiconductor component is a Schottky diode, one or more trenches are formed in an epitaxial layer of a first conductivity type that is formed over a semiconductor substrate of the first conductivity type. The trenches may extend into the semiconductor material. Epitaxial semiconductor material of a second conductivity type is selectively grown along the sidewalls of the trenches. An anode contact is formed in contact with the epitaxial layer and the selectively grown epitaxial material and a cathode contact is formed in contact with the semiconductor substrate.

Abstract: Provided is a method of fabricating a Schottky barrier transistor. The method includes (a) forming a pair of cavities for forming a source forming portion and a drain forming portion having a predetermined depth and parallel to each other and a channel forming portion having a fin shape between the cavities in a substrate; (b) filling the pair of cavities with a metal; (c) forming a channel, a source, and a drain by patterning the channel forming portion, the source forming portion, and the drain forming portion in a direction perpendicular to a lengthwise direction of the channel forming portion; (d) sequentially forming a gate oxide layer and a gate metal layer that cover the channel, the source, and the drain on the substrate; and (e) forming a gate electrode corresponding to the channel by patterning the gate metal layer, wherein one of the operations (b) through (e) further comprises forming a Schottky barrier by annealing the substrate.

Abstract: A depletion mode (D-mode) field effect transistor (FET) is monolithically integrated with an enhancement mode (E-mode) FET in a multi-layer structure. The multi-layer structure includes a channel layer overlaid by a barrier layer overlaid by an ohmic contact layer. Source and drain contacts of the D-mode and E-mode FETs are coupled to the ohmic contact layer. A gate contact of the D-mode and E-mode FETs is coupled to the barrier layer. An amorphized region is provided beneath the E-mode gate contact within the barrier layer. The amorphized region forms a buried E-mode Schottky contact with the barrier layer. An alternative embodiment couples the gate contact of the D-mode transistor to a first layer that overlies the barrier layer, and provides a similar D-mode amorphized region within the first layer.

Abstract: A copper interconnect having a transition metal-silicon-nitride barrier (106). A transition metal-nitride is co-deposited with Si by reactive sputtering in a Si containing ambient to form barrier (106). The copper (110) is then deposited over the transition metal-silicon-nitride barrier (108) with good adhesion.

Abstract: A method for forming an ohmic contact and a zener zap diode in an integrated circuit includes forming a first contact opening in the insulating layer over a first diffusion region to expose the semiconductor substrate; forming a barrier metal layer on the insulating layer and in the first contact opening; forming a second contact opening in the barrier metal layer over a second diffusion region and the insulating layer to expose the semiconductor substrate; forming a third contact opening in the barrier metal layer and the insulating layer over a third diffusion region to expose the semiconductor substrate; forming an aluminum layer on the barrier metal layer and the insulating layer and in the first, second and third contact openings; and patterning the aluminum layer to form the ohmic contact over the first diffusion region and the zener zap diode over the second and third diffusion regions.

Abstract: The present invention provides a method for manufacturing a semiconductor device. In one embodiment, the method for manufacturing the semiconductor device includes a method for manufacturing a zener diode, including among others, forming a doped well (240) within a substrate (210) and forming a suppression implant (420) within the substrate (210). The method for manufacturing the zener diode may further include forming a cathode (620) and an anode (520) within the substrate (210), wherein the suppression implant (420) is located proximate the doped well (240) and configured to reduce threading dislocations.

Abstract: A semiconductor device according to some embodiments includes a semiconductor layer having a first conductivity type and a surface in which an active region of the semiconductor device is defined. A plurality of spaced apart first doped regions are arranged within the active region. The plurality of first doped regions have a second conductivity type that is opposite the first conductivity type, have a first dopant concentration, and define a plurality of exposed portions of the semiconductor layer within the active region. The plurality of first doped regions are arranged as islands in the semiconductor layer. A second doped region in the semiconductor layer has the second conductivity type and has a second dopant concentration that is greater than the first dopant concentration.

Abstract: First and second synthetic diamond regions are doped with boron. The second synthetic diamond region is doped with boron to a greater degree than the first synthetic diamond region, and in physical contact with the first synthetic diamond region. In a further example embodiment, the first and second synthetic diamond regions form a diamond semiconductor, such as a Schottky diode when attached to at least one metallic lead.

Abstract: A trenched semiconductor power device that includes a plurality of trenched gates surrounded by source regions near a top surface of a semiconductor substrate encompassed in body regions. Each of the body regions extended between two adjacent trenched gates further having a gap exposing a top surface above an epitaxial layer above said semiconductor substrate. The trenched semiconductor power device further includes a Schottky junction barrier layer covering the top surface above the epitaxial layer between the trenched gate thus forming embedded Schottky diodes between adjacent trenched gates.

Abstract: An integrated circuit structure in which a plurality of Schottky diodes and a capacitor are integrally formed. The integrated circuit structure includes a substrate including an N-type semiconductor doped with N-type impurities and a P-type semiconductor doped with P-type impurities; a first conductive layer laminated on the substrate so that the first conductive layer is electrically connected to the N-type semiconductor and the P-type semiconductor; a dielectric layer laminated on an upper surface of the first conductive layer; and a second conductive layer laminated on an upper surface of the dielectric layer so that the second conductive layer forms a capacitor together with the first conductive layer and the dielectric layer. Accordingly, when the integrated circuit structure is used in a rectification circuit, the size of an entire circuit can be reduced.

Abstract: A Schottky barrier silicon carbide device has a Re Schottky metal contact. The Re contact 27 is thicker than 250 Angstroms and may be between 2000 and 4000 Angstroms. A termination structure is provided by ion milling an annular region around the Schottky contact.

Abstract: Since VF and IR characteristics of a Schottky barrier diode are in a trade-off relationship, there has heretofore been a problem that an increase in a leak current is unavoidable in order to realize a low VF. Moreover, there has been a known structure which suppresses the leak current in such a manner that a depletion layer is spread by providing P+ regions and a pinch-off effect is utilized. However, in reality, it is difficult to completely pinch off the depletion layer. P+ type regions are provided, and a low VF Schottky metal layer is allowed to come into contact with the P+ type regions and depletion regions therearound. A low IR Schottky metal layer is allowed to come into contact with a surface of a N type substrate between the depletion regions. When a forward bias is applied, a current flows through the metal layer of low VF characteristic. When a reverse bias is applied, a current path narrowed by the depletion regions is formed only in the metal layer portion of low IR characteristic.

Abstract: A semiconductor device includes: a semiconductor element having a first surface and a second surface; a first electrode disposed on the first surface of the element; a second electrode disposed on the second surface of the element; and an insulation film covers a part of the first electrode, the first surface of the element and a part of a sidewall of the element. The above semiconductor device has small dimensions and a high breakdown voltage.

Abstract: Provided are a Schottky barrier tunnel single electron transistor and a method of manufacturing the same that use a Schottky barrier formed between metal and semiconductor by replacing a source and a drain with silicide as a reactant of silicon and metal, instead of a conventional method of manufacturing a single electron transistor (SET) that includes source and drain regions by implanting dopants such that an artificial quantum dot is formed in a channel region. As a result, it does not require a conventional PADOX process to form a quantum dot for a single electron transistor (SET), height and width of a tunneling barrier can be artificially adjusted by using silicide materials that have various Schottky junction barriers, and it is possible to improve current driving capability of the single electron transistor (SET).

Abstract: To reduce a reverse leakage current in a Schottky barrier diode with achieving a lower forward voltage Vf and a smaller capacitance than in the related art, a Schottky barrier diode includes a semiconductor layer of a first conductivity type, a first electrode which is a metal layer forming a Schottky contact with a main surface of the semiconductor layer, a second electrode forming an ohmic contact with an opposite main surface of the semiconductor layer, a buried layer of a second conductivity type formed within the semiconductor layer so as not to be in contact with the first electrode, where the second conductivity type has a different charge carrier from the first conductivity type, and a guard ring of the second conductivity type formed within the semiconductor layer so as to be in contact with the first electrode and also to surround the buried layer without contacting with the buried layer.

Abstract: A description is given of a semiconductor component comprising a drift zone of a first conduction type and at least one Schottky metal zone arranged in the drift zone, and of a method for producing a semiconductor component.

Abstract: Cobalt silicide (CoSi2) Schottky diodes fabricated per the current art suffer from excess leakage currents in reverse bias. In this invention, an floating p-type region encircles each anode of a CoSi2 Schottky diode comprising of one or more CoSi2 anodes. The resulting p-n junction forms a depletion region under the Schottky junction that reduces leakage current through the Schottky diodes in reverse bias operation.

Abstract: A variable-resistance material memory (VRMM) device includes a container conductor disposed over an epitaxial semiconductive prominence that is coupled to a VRMM. A VRMM device may also include a conductive plug in a recess that is coupled to a VRMM. A VRMM array may also include a conductive plug in a surrounding recess that is coupled to a VRMM. Apparatuses include the VRMM with one of the diode constructions.

Abstract: A process for integrating a Schottky contact inside the apertures of the elementary cells that constitute the integrated structure of the insulated gate power device in a totally self-alignment manner does not requires a dedicated masking step. This overcomes the limits to the possibility of increasing the packing density of the cellular structure of the integrated power device, while permitting improved performances of the co-integrated Schottky diode under inverse polarization of the device and producing other advantages. A planar integrated insulated gate power device with high packing density of the elementary cells that compose it, having a Schottky diode electrically in parallel to the co-integrated device, is also disclosed.

Abstract: Claimed and disclosed is a semiconductor device including a transistor having a gate insulating film structure containing nitrogen or fluorine in a compound, such as metal silicate, containing metal, silicon and oxygen, a gate insulating film structure having a laminated structure of an amorphous metal oxide film and metal silicate film, or a gate insulating film structure having a first gate insulating film including an oxide film of a first metal element and a second gate insulating film including a metal silicate film of a second metal element.

Abstract: A semiconductor diode includes a drift region of a first conductivity type and an anode region of a second conductivity type in the drift region such that the anode region and the drift region form a pn junction therebetween. A first highly doped silicon region of the first conductivity type extends in the drift region, and is laterally spaced from the anode region such that upon biasing the semiconductor power diode in a conducting state, a current flows laterally between the anode region and the first highly doped silicon region through the drift region. A plurality of trenches extends into the drift region perpendicular to the current flow. Each trench includes a dielectric layer lining at least a portion of the trench sidewalls and also includes at least one conductive.

Abstract: A semiconductor device including a schottky device and a trench type semiconductor switching device such as a MOSFET formed in a common die.

Abstract: A process for producing a Schottky junction type semiconductor device includes the steps of forming a Schottky electrode on a surface of a silicon carbide epitaxial layer, wherein a Schottky electrode made of molybdenum, tungsten, or an alloy thereof is formed on the surface of the silicon carbide epitaxial layer and is subjected to heat treatment so as to induce an alloying reaction at an interface of the silicon carbide epitaxial layer and the Schottky electrode, thereby forming an alloy layer at the interface, whereby the height of a Schottky barrier is controlled while maintaining an n-factor at a nearly constant low value.

Abstract: A semiconductor structure in which the contact resistance in the contact opening is reduced as well as a method of forming the same are provided. This is achieved in the present invention by replacing conventional contact metallurgy, such as tungsten, or a metal silicide, such as Ni silicide or Cu silicide, with a metal germanide-containing contact material. The term “metal germanide-containing” is used in the present application to denote a pure metal germanide (i.e., MGe alloy) or a metal germanide that includes Si (i.e., MSiGe alloy).

Abstract: A semiconductor structure. The structure includes (a) a semiconductor channel region, (b) a semiconductor source block in direct physical contact with the semiconductor channel region; (c) a source contact region in direct physical contact with the semiconductor source block, wherein the source contact region comprises a first electrically conducting material, and wherein the semiconductor source block physically isolates the source contact region from the semiconductor channel region, and (d) a drain contact region in direct physical contact with the semiconductor channel region, wherein the semiconductor channel region is disposed between the semiconductor source block and the drain contact region, and wherein the drain contact region comprises a second electrically conducting material; and (e) a gate stack in direct physical contact with the semiconductor channel region.

Abstract: A trench MOS Schottky barrier device has a metal oxide gate dielectric such as TiSi lining the trench wall to increase the efficiency of the elemental cell and to improve depletion in the mesa during reverse bias. A reduced mask process is used in which a single layer of titanium or other metal is deposited on an underlying gate oxide layer on the trench walls and directly atop the mesa between adjacent trenches. A common thermal treatment causes the Ti to diffuse into the SiO2 gate oxide to form the TiO2 gate and to form the TiSi Schottky barrier on the top surface of the mesa.

Abstract: In semiconductor devices and methods for their manufacture, the semiconductor devices are arranged as a trench-Schottky-barrier-Schottky diode having a pn diode as a clamping element (TSBS-pn), and having additional properties compared to usual TSBS elements which make possible adaptation of the electrical properties. The TSBS-pn diodes are produced using special manufacturing methods, are arranged in their physical properties such that they are suitable for use in a rectifier for a motor vehicle generator, and are also able to be operated as Z diodes.

Abstract: A Schottky diode is formed on an isolated well (e.g., a P-well formed in a buried N-well), and utilizes cobalt silicide (CoSi2) structures respectively formed on heavily doped and lightly doped regions of the isolated well to provide the Schottky barrier and backside (ohmic) contact structures of the Schottky diode. The surrounding buried N-well is coupled to a bias voltage. The Schottky barrier and backside contact structures are separated by isolation structures formed using polycrystalline silicon, which is used to form the gate structure of CMOS FETs, in order to minimize forward resistance. Heavily doped drain (HDD) diffusions and lightly doped drain (LDD) diffusions, which are used to form source and drain diffusions of the FET, are utilized to form a suitable contact diffusion under the backside contact silicide.