Abstract: Ternary CAM cells are provided that have extremely small layout footprint size and efficient layout aspect ratios that enhance scalability. The cells also have high degrees of symmetry that facilitate high yield interconnections to bit, data and match lines. A 16T ternary CAM cell includes first and second pairs of access transistors that extend adjacent a first side of the cell, and first and second pairs of cross-coupled inverters that extend adjacent a second side of the cell. First and second halves of a 4T compare circuit are also provided. The first half of the 4T compare circuit is positioned so that is extends between the first pair of access transistors and the first pair of cross-coupled inverters. Similarly, the second half of the 4T compare circuit is positioned so that it extends between the second pair of access transistors and the second pair of cross-coupled inverters.

Abstract: Ternary CAM cells are provided that have extremely small layout footprint size and efficient layout aspect ratios that enhance scalability. The cells also have high degrees of symmetry that facilitate high yield interconnections to bit, data and match lines. A 16T ternary CAM cell includes first and second pairs of access transistors that extend adjacent a first side of the cell, and first and second pairs of cross-coupled inverters that extend adjacent a second side of the cell. First and second halves of a 4T compare circuit are also provided. The first half of the 4T compare circuit is positioned so that is extends between the first pair of access transistors and the first pair of cross-coupled inverters. Similarly, the second half of the 4T compare circuit is positioned so that it extends between the second pair of access transistors and the second pair of cross-coupled inverters.

Abstract: A method of forming edge metal lines to interconnect features in a semiconductor device. One embodiment comprises the steps of: patterning a first insulating layer to form a first feature having a first sidewall; depositing a metal layer over the first feature; and etching the metal layer so that a first edge metal line is formed adjacent to the first sidewall. The edge metal line may be substantially anisotropically etched to form the edge metal line. The edge metal line may comprise a plurality of metal layers. The edge metal line may also interconnect features in a semiconductor device (e.g., contacts). The method may further comprise the step of forming a protective coating over a portion of the metal layer such that the etching step may form a metal interconnect line and the edge metal line from the same metal layer. The metal interconnect line may comprise a bus that may have more current carrying capacity than the edge metal line.

Abstract: An MOS transistor for use in an integrated circuit is fabricated with a self-aligning contact and interconnect structure which allows for higher packing density. Self-aligning source and drain contacts overlap the gate but are prevented from a short circuiting to the gate by oxide insulation between the source/drain contacts and the gate, and a layer of silicon nitride above the gate. Contacts to the gate are made on top of the gate over the active region of the transistor because the source and drain regions are protected by a hardened layer of photoresist during etching of insulation to expose the gate contact. Source, drain and gate contacts are protected by a layer of titanium silicide so that interconnects are not required to completely cover these areas. Low resistance interconnects are formed of doped polysilicon covered by titanium silicide encapsulated by a thin film of titanium nitride.

Abstract: An MOS transistor for use in an integrated circuit, particularly CMOS integrated circuits, is fabricated with a self-aligning contact and interconnect structure which allows for higher packing density. Self-aligning source and drain contacts overlap the gate but are prevented from short circuiting to the gate by oxide insulation between the source/drain contacts and the gate, and a layer of silicon nitride above the gate. Contacts to the gate are made on top of the gate over the active region of the transistor because the source and drain regions are protected by a hardened layer of photoresist during etching of insulation to expose the gate contact. Source, drain and gate contacts are protected by a layer of titanium silicide so that interconnects are not required to completely cover these areas. Low resistance interconnects are formed of titanium silicide encapulated by a thin film of titanium nitride.

Abstract: An MOS transistor for use in an integrated circuit is fabricated with a self-aligning contact and interconnect structure which allows for higher packing density. Self-aligning source and drain contacts overlap the gate but are prevented from a short circuiting to the gate by oxide insulation between the source/drain contacts and the gate, and a layer of silicon nitride above the gate. Contacts to the gate are made on top of the gate over the active region of the transistor because the source and drain regions are protected by a hardened layer of photoresist during etching of insulation to expose the gate contact. Source, drain and gate contacts are protected by a layer of titanium silicide so that interconnects are not required to completely cover these areas. Low resistance interconnects are formed of doped polysilicon covered by titanium silicide encapsulated by a thin film of titanium nitride.

Abstract: A CMOS integrated circuit uses self-aligned transistors combined with local planarization in the vicinity of the transistors so as allow local interconnects which are free of bridging, have good continuity over the planarized topography and are compatible with the self-alignment schemes, hence conserving chip real estate. After formation of self-aligned insulated transistor gates and active transistor regions, the integrated circuit structure is planarized by formation of an oxide layer and a reflowed overlying glass layer. The glass layer and underlying oxide layer are removed only in the area of the buried contact, while an overlying metal or polysilicon conductive layer contacts the upper surface of certain of the transistor gate structures, the topside insulating layer of which has been removed for this purpose.

Abstract: Transistor fabrication methods are provided which are suitable, for example, for transistors with current carrying elements above a semiconductor substrate. Only few mask alignments define critical dimensions such as the channel length of a MOS transistor. In one embodiment in which the channel region overlies the gate, a first mask is formed over the channel region, and then an LDD implant is carried out. A second mask is then formed over the LDD portion of the drain region. The second mask is allowed to extend over the first mask. A heavy doping implant is then carried out. Thus an LDD structure can be provided on the drain side but not on the source side with only one mask--the first mask--defining the channel length. In some embodiments, both masks include photoresist. The first photoresist mask is hardened to prevent its lifting during development of the resist of the second mask.

Abstract: A CMOS integrated circuit fabrication technique for forming self-aligned transistors combined with local planarization in the vicinity of the transistors so as to allow local interconnects which are free of bridging, have good continuity over the planarized topography and are compatible with the self-alignment schemes, hence conserving chip real estate. The technique is compatible with planarization schemes using BPSG, BPTEOS, SOG or CMP. After formation of self-aligned insulated transistor gates and active transistor regions, the integrated circuit structure is planarized by formation of an oxide layer and a reflowed overlying glass layer. The glass layer is etched back to planarize the surface. Using a buried contact mask the remaining portions of the glass layer and underlying oxide layer are removed in the area of the buried contact only.

Abstract: A load resistor for use in a semiconductor integrated circuit consists of two portions of conductive material, typically strips of either a silicide or a composite polycrystalline silicon layer and silicide layer formed thereon, formed on a semiconductor substrate and separated from each other by a selected distance. An electrically conductive dopant diffusion barrier is formed on the first and second portions of conductive material. A polycrystalline silicon material is then placed on the structure such that one portion of the polycrystalline silicon material is in ohmic contact through the diffusion barrier with the first portion of conductive material and the other portion of the polycrystalline silicon material is in ohmic contact through the diffusion barrier with the second portion of conductive material. Typically the polycrystalline silicon material is placed on an insulation layer formed on the semiconductor substrate in the portion of the substrate between the two portions of conductive material.

Abstract: A load resistor for use in a semiconductor integrated circuit consists of two portions of conductive material, typically strips of either a silicide or a composite polycrystalline silicon layer and silicide layer formed thereon, formed on a semiconductor substrate and separated from each other by a selected distance. An electrically conductive dopant diffusion barrier is formed on the first and second portions of conductive material. A polycrystalline silicon material is then placed on the structure such that one portion of the polycrystalline silicon material is in ohmic contact through the diffusion barrier with the first portion of conductive material and the other portion of the polycrystalline silicon material is in ohmic contact through the diffusion barrier with the second portion of conductive material. Typically the polycrystalline silicon material is placed on an insulation layer formed on the semiconductor substrate in the portion of the substrate between the two portions of conductive material.

Abstract: An MOS transistor for use in an integrated circuit, particularly CMOS integrated circuits, is fabricated with a self-aligning contact and interconnect structure which allows for higher packing density. Self-aligning source and drain contacts overlap the gate but are prevented from short circuiting to the gate by oxide insulation between source/drain contacts and the gate, and a layer of silicon nitride above the gate. Contacts to the gate are made on top of the gate over the active region of the transistor because the source and drain regions are protected by a hardened layer of photoresist during etching of insulation to expose the gate contact. Source, drain and gate contacts are protected by a layer of titanium silicide so that interconnects are not required to completely cover these areas. Low resistance interconnects are formed of titanium silicide encapsulated by a thin film of titanium nitride.

Abstract: A compact cell design for a static random access memory cell is achieved. The cell has two transistors with gates substantially parallel to each other. One interconnect connects the gate of one transistor to an electrode of the other transistor. Another interconnect connects the gate of the other transistor to an electrode of the first transistor. The two gates and the two interconnects form substantially a rectangle. A power supply circiut line is disposed outside the rectangle. This line and the two interconnects are formed from one conductive layer.