Abstract: A nitrogen implanted region formed substantially below and substantially adjacent to a source/drain region of an IGFET forms a liner to retard the diffusion of the source/drain dopant atoms during a subsequent heat treatment operation such as an annealing step. The nitrogen liner may be formed by implantation of nitrogen to a given depth before the implantation of source/drain dopant to a lesser depth. Nitrogen may also be introduced into regions of the IGFET channel region beneath the gate electrode for retarding subsequent lateral diffusion of the source/drain dopant. Such nitrogen introduction may be accomplished using one or more angled implantation steps, or may be accomplished by annealing an implanted nitrogen layer formed using a perpendicular implant aligned to the gate electrode. The liner may be formed on the drain side of the IGFET or on both source and drain side, and may be formed under a lightly-doped region or under a heavily-doped region of the drain and/or source.

Abstract: A semiconductor device includes a substrate, a gate structure, a plurality of sidewall spacers, and a plurality of first silicide layers. The gate structure is positioned above the substrate. The plurality of sidewall spacers are positioned adjacent to the gate structure. The first silicide layers are positioned in the substrate and have first ends that extend underneath the sidewall spacers. A method for forming a semiconductor device includes forming a gate structure above a substrate. A plurality of sidewall spacers are formed adjacent the gate structure. An implant material is disposed into the substrate using a tilted implantation process that is adapted to form first implant regions in the substrate. The implant regions have first ends that extend underneath the sidewall spacers by a first distance.

Abstract: Methods of fabricating a silicide layer on a substrate or transistor structures thereon are provided. An exemplary method includes the steps of depositing a layer of metal on a substrate that has a pn junction. The metal layer and the substrate are heated to react the metal with the substrate and form the silicide layer. Any unreacted metal is removed. The substrate and the silicide layer are heated above the agglomeration threshold temperature of any filaments of the silicide layer penetrating the pn junction but below the agglomeration threshold temperature of the silicide layer. The method eliminates silicide filaments, particularly in cobalt silicide processing, that can otherwise penetrate the pn junction of a transistor source/drain region a lead to reverse-bias diode-leakage currents.

Abstract: In a plurality of series-coupled IGFET devices, wherein each pair of devices in the series shares a common source/drain terminal, only the source/drain regions acting as drain terminals are provided with a lightly-doped region. The presence of the lightly-doped source/drain regions in the portions of the source/drain regions acting as drain terminals provides protection against “hot-carrier” effects. By not having lightly-doped portions in portions of the source/drain regions acting as sources, the resistance resulting from the presence of the additional lightly-doped portions of the remaining source/drain regions in the series of IGFET devices results in lower resistance experienced by the conduction current. According to a second embodiment of the invention, only the non-shared source/drain terminal acting as drain terminal is provided with a lightly-doped region.

Abstract: An IGFET with a gate electrode and insulative spacers in a trench is disclosed. The IGFET includes a trench with opposing sidewalls and a bottom surface in a semiconductor substrate, a gate insulator on the bottom surface, a gate electrode on the gate insulator, and insulative spacers between the gate electrode and the sidewalls.

Abstract: An IGFET with elevated source and drain regions in close proximity to a gate with sloped sidewalls is disclosed. A method of making the IGFET includes forming a lower gate level over a semiconductor substrate, wherein the lower gate level includes a top surface, a bottom surface and sloped opposing sidewalls, and the top surface has a substantially greater length than the bottom surface, and depositing a semiconducting layer on the lower gate level and on underlying source and drain regions of the semiconductor substrate to form an upper gate level on the lower gate level, an elevated source region on the underlying source region, and an elevated drain region on the underlying drain region. The elevated source and drain regions are separated from the lower gate level due to a retrograde slope of the sidewalls of the lower gate level, and the elevated source and drain regions are separated from the upper gate level due to a lack of step coverage in the semiconducting layer.

Abstract: A transistor is provided having a gate conductor produced with ultra fine geometries. The gate conductor is metallic and is sized using deposition rather than photolithography. The deposition process can be closely controlled to achieve gate lengths less than a few tenths of a micron. The metallic gate conductor serves to source metal atoms during anneal of lightly doped drain regions. The metal atoms migrate to the gate dielectric directly beneath the gate conductor to convert the gate dielectric to a high K dielectric. The high K dielectric is substantially resistant to breakdown yet enjoys the benefits of high speed operation and low threshold turn-on.

Abstract: An IGFET with metal spacers is disclosed. The IGFET includes a gate electrode on a gate insulator on a semiconductor substrate. Sidewall insulators are adjacent to opposing vertical edges of the gate electrode, and metal spacers are formed on the substrate and adjacent to the sidewall insulators. The metal spacers are electrically isolated from the gate electrode but contact portions of the drain and the source. Preferably, the metal spacers are adjacent to edges of the gate insulator beneath the sidewall insulators. The metal spacers are formed by depositing a metal layer over the substrate then applying an anisotropic etch. In one embodiment, the metal spacers contact lightly and heavily doped drain and source regions, thereby increasing the conductivity between the heavily doped drain and source regions and the channel underlying the gate electrode. The metal spacers can also provide low resistance drain and source contacts.

Abstract: The present invention is directed to a transistor formed above a layer of a dielectric material and a method of making same. In one illustrative embodiment, the method comprises forming a layer of dielectric material, forming a plurality of source/drain regions comprised of polysilicon above said layer of dielectric material and between said source/drain regions. The method further comprises forming a gate dielectric above said layer of polysilicon and forming a gate conductor above said gate dielectric. The transistor structure is comprised of a layer of dielectric material, a plurality of source/drain regions positioned above the layer of dielectric material, and a layer of polysilicon positioned above said layer of dielectric material and between said source/drain regions. The structure further comprises a gate dielectric positioned above said layer of polysilicon and a gate conductor positioned above said gate dielectric.

Abstract: An optical monitoring of electrical characteristics of devices in a semiconductor is performed during an anneal step to detect the time annealing is complete and activation occurs. A surface photovoltage measurement is made during annealing to monitor the charge state on the surface of a substrate wafer to determine when the substrate is fully annealed. The surface photovoltage measurement is monitored, the time of annealing is detected, and a selected over-anneal is controlled. The surface photovoltage (SPV) measurement is performed to determine a point at which a dopant or impurity such as boron or phosphorus is annealed in a silicon lattice. In some embodiments, the point of detection is used as a feedback signal in an RTA annealing system to adjust a bank of annealing lamps for annealing and activation uniformity control. The point of detection is also used to terminate the annealing process to minimize D.sub.t.

Abstract: In the fabrication of an integrated circuit having both N MOSFETs and P MOSFETs in which the respective N-type species and P-type species have substantially different diffusivities, the source implant of the dopant species having a the higher diffusivity is advantageously delayed until a contact masking process step. By delaying the dopant species having the higher diffusivity, depletion of the dopant by subsequent annealing steps is avoided. P MOSFETs formed using a high diffusivity boron implant species in an integrated circuit including both P MOSFETs and N MOSFET are fabricated with no source implant in the source regions during formation of the gate electrodes and sidewall spaces.

Abstract: The present invention is directed to a transistor having a stacked silicide metal and method of making same. In general, the method comprises forming a layer of nitrogen-bearing silicon dioxide above the gate conductor and the source and drain regions of a transistor. In one illustrative embodiment, the method further comprises forming a layer of titanium above at least the surface of the gate conductor and the source and drain regions. Thereafter, a layer of cobalt is formed above the layer of titanium. The transistor is then subjected to a heat treating process such that at least the layer of cobalt forms a metal silicide. Also disclosed herein is a partially formed transistor comprised of a gate conductor, a source region and a gate region. In one illustrative embodiment, the transistor is further comprised of a layer of nitrogen-bearing silicon dioxide formed above the gate conductor and the source and drain regions.

Abstract: An interlevel interconnect is formed in a window opened through an isolation layer and through an etch barrier to expose an electrode surface and an adjacent isolation barrier. The interlevel interconnect may be disposed on substantially all of a portion of the underlying electrode such as an insulated gate field effect transistor (IGFET) source/drain region surface. The etch barrier provides controlled etching to allow for overlap of the interlevel interconnect onto the isolation barrier without increased parasitic capacitance relative to conventional contact misalignments. Furthermore, allaying concerns of overlapping allows for increased utilization of source/drain region surface area by the interlevel interconnect. Furthermore, the etch barrier allows the interlevel interconnect to strap electrodes of a plurality of circuit devices while exhibiting nominal if any substrate to interlevel interconnect leakage currents.

Abstract: An integrated circuit and a method of making the same are provided. The circuit includes a substrate that has a trench formed therein defining and isolating first and second active area and an upper surface. The circuit includes a capacitor that has a first insulating layer formed in the trench, a conductor layer formed on the first insulating layer, and a second insulating layer formed on the first insulating layer that fills the trench. The conductor layer is positioned substantially at or below the upper surface. The circuit integrates trench isolation structure with a capacitor that may be used as a filter between power and ground. The method integrates capacitor formation with trench isolation formation.

Abstract: A semiconductor topography for a transistor having an ultra-narrow gate conductor. A method for forming the semiconductor topography may include etching a patterning layer extending across a conductive gate layer to form an opening extending to an upper surface of the conductive gate layer. Subsequently, a masking layer is formed upon the exposed upper surface of the conductive gate layer. The patterning layer and portions of the conductive gate layer not shielded by the masking layer are then removed to form a gate conductor. Lightly doped drain impurity areas may then be formed in the semiconductor substrate aligned with sidewall surfaces of the gate conductor. In an embodiment, spacers may be formed adjacent sidewall surfaces of the gate conductor substantially simultaneously with removal of the masking layer and portions of a gate dielectric layer not shielded by the gate conductor.

Abstract: A method is presented for forming a transistor wherein a silicide layer is formed upon an impurity region of a semiconductor substrate. After forming the silicide layer, a gate structure is preferably formed upon an exposed portion of the semiconductor substrate; however, the silicide layer may be formed after forming the gate structure. In order to form the gate structure, a layer of sacrificial material is first formed above the semiconductor substrate. An opening is then patterned through the layer of sacrificial material such that a portion of the semiconductor substrate is exposed. The gate structure preferably includes a metal gate conductor and a metal oxide gate dielectric.

Abstract: Various methods of fabricating a silicide layer, and devices incorporating the same are provided. In one aspect, a method of fabricating a silicide layer on a substrate is provided. The method includes the steps of damaging the crystal structure of a portion of the substrate positioned beneath the spacer and depositing a layer of metal on the substrate. The metal layer and the substrate are heated to react the metal with the substrate and form the silicide layer, whereby a portion of the silicide layer extends laterally beneath the spacer. Any unreacted metal is removed. The method enables fabrication of silicide layers with substantial lateral encroachment into LDD structures, resulting in lower possible source-to-drain resistance and enhanced performance for transistors.

Abstract: The present invention is directed to a semiconductor device having a reduced feature size and a method of making same. The device is comprised of a gate dielectric positioned above a semiconducting substrate, and a gate conductor positioned above said gate dielectric. The width of the gate dielectric being less than the width of the gate conductor. The device further comprises a plurality of sidewall spacers adjacent said conductor. The method is comprised of forming a gate dielectric above the surface of a semiconducting substrate, forming a gate conductor above the gate dielectric, and wet etching the gate dielectric to a finished width that is less than the width of the gate conductor.

Abstract: The present invention is directed to a method of forming ultra shallow extensions in a transistor and a device incorporating same. The method comprises forming a gate dielectric and a gate conductor above a surface of a semiconducting substrate and forming a first plurality of sidewall spacers adjacent the gate dielectric and the gate conductor. The method continues with implanting the substrate with a dopant material to form a plurality of doped regions in the substrate, heating the substrate to drive the dopant material towards the gate dielectric, and removing the first plurality of sidewall spacers. The method further comprises forming a second plurality of sidewall spacers adjacent the gate dielectric and the gate conductor, and performing a second ion implantation process to complete the formation of source/drain regions in said substrate.

Abstract: An isolation structure and a method of making the same are provided. In one aspect, the method includes the steps of forming a trench in the substrate and a first insulating layer in the trench that has a bottom, a first sidewall and a second sidewall. Silicon nitride is deposited in the trench. Silicon nitride is removed from the bottom of the first insulating layer to establish a layer of silicon nitride on the first and second sidewalls by performing a first plasma etch of the deposited silicon nitride with an ambient containing He, SF.sub.6, and HBr, and a second plasma etch with an ambient containing He, SF.sub.6, and HBr. An insulating material is deposited in the trench. The method provides for reliable manufacture of nitride liners for trench isolation structures. Scaling is enhanced and the potential for parasitic leakage current due to liner oxide fracture or irregularity is reduced.