Abstract: A method of making an IGFET and a protected resistor includes providing a semiconductor substrate with an active region and a resistor region, forming a gate over the active region, forming a diffused resistor in the resistor region, forming an insulating layer over the gate and the diffused resistor, forming a masking layer over the insulating layer that covers the resistor region and includes an opening above the active region, applying an etch using the masking layer as an etch mask so that unetched portions of the insulating layer over the active region form spacers in close proximity to opposing sidewalls of the gate and an unetched portion of the insulating layer over the resistor region forms a resistor-protect insulator, and forming a source and a drain in the active region. In this manner, a single insulating layer provides both sidewall spacers for the gate and a resistor-protect insulator for the diffused resistor.

Abstract: A high density integrated circuit structure and method of making the same includes providing a first silicon substrate structure having semiconductor device formations in accordance with a first circuit implementation and metal interlevel lines disposed on a top surface thereof and a second silicon substrate structure having a second circuit implementation and metal interlevel lines disposed on a top surface thereof. The first substrate structure includes a planarized low-K dielectric disposed between the metal interlevel lines and a protective coating separating the metal interlevel lines from the low-K dielectric, the metal interlevel lines of the first silicon substrate structure have a melting temperature on the order of less than 500.degree. C. and the low-K dielectric having a dielectric K-value in the range of 2.0-3.8.

Abstract: A dual level transistor integrated circuit and a fabrication technique for making the integrated circuit. The dual level transistor is an integrated circuit in which a first transistor is formed on an upper surface of a global dielectric and a second transistor is formed on an upper surface of a first local substrate such that the second transistor is vertically displaced from the first transistor. The first local substrate is formed upon a first inter-substrate dielectric. By vertically displacing the first and second transistors, the lateral separation required to isolate first and second transistors in a typical single plane process is eliminated. The integrated circuit includes a semiconductor global substrate. The integrated circuit further includes a first transistor. The first transistor includes a first gate dielectric formed on an upper surface of the global substrate and a first conductive gate structure formed on an upper surface of the first dielectric.

Abstract: A high density integrated circuit structure and method of making the same includes providing a first silicon substrate structure having semiconductor device formations in accordance with a first circuit implementation and metal interlevel lines disposed on a top surface thereof and a second silicon substrate structure having a second circuit implementation and metal interlevel lines disposed on a top surface thereof. The first substrate structure includes a planarized low-K dielectric disposed between the metal interlevel lines and a protective coating separating the metal interlevel lines from is the low-K dielectric, the metal interlevel lines of the first silicon substrate structure have a melting temperature on the order of less than 500.degree. C. and the low-K dielectric having a dielectric K-value in the range of 2.0-3.8.

Abstract: An IGFET device isolation structure fabrication scheme includes the formation of electrically insulating isolation structures that extend into the substrate and extend above the surface of the substrate. The isolation structures are formed by providing a first mask to form trenches in the substrate. A layer of silicon dioxide is then deposited, filling the trenches and extending above the surface of the substrate. A second mask layer is formed. The second mask layer shadows the trench regions that were formed in the substrate. The silicon dioxide not shadowed by the second mask layer is removed, leaving isolation structures that extend both into the substrate and which rise above the substrate. A gate structure is formed in the region between two isolation structures, and, in the preferred embodiment, the gate structure extends above the substrate to the same height as the isolation structures. The isolation structures and the gate structure can be used to provide self-aligned doped source/drain regions.

Abstract: An asymmetrical IGFET including a lightly and heavily doped drain regions and an ultra-heavily doped source region is disclosed. Preferably, the lightly doped drain region and ultra-heavily doped source region provide channel junctions.

Abstract: A second transistor is formed a spaced distance above a first transistor. An interlevel dielectric is first deposited upon the upper surface of the first semiconductor substrate and the first transistor. A second semiconductor substrate, preferably comprising polysilicon, is then formed into the interlevel dielectric. A second transistor is then formed on the upper surface of the second semiconductor substrate. The second transistor is a spaced distance above the first transistor. The two transistors are a lateral distance apart which is smaller than the distance that can be achieved by conventional fabrication of transistors on the upper surface of the wafer. Transistors are more closely packed which results in an increase in the number of devices produced per wafer.

Abstract: A process is provided for producing active and passive devices on various levels of a semiconductor topography. As such, the present process can achieve device formation in three dimensions to enhance the overall density at which an integrated circuit is formed. The multi-level fabrication process not only adds the to the overall circuit density, but does so with emphasis placed on high performance interconnection between devices on separate levels. The interconnect configuration is made as short as possible between features within one transistor level to features within another transistor level. This interconnect scheme lowers resistivity by forming a gate conductor of an upper level transistor upon a gate conductor of lower level transistor. Alternatively, the gate conductors can be a single conductive entity. In order to abut the gate conductors together, or form a single gate conductor, the upper level transistor is inverted relative to the lower level transistor.

Abstract: A resistor is formed between devices in an integrated circuit by forming a patterned trench in an intralayer dielectric (ILD) deposited over the devices, filling the trench with polysilicon and planarizing the polysilicon. The resistance of the resistor is defined by determining and selecting the size and form of the trench including the width, length, depth and orientation of the trench. In some embodiments, the resistance of the resistor is also controlled by adding selected amounts and species of dopants to the polysilicon. In some embodiments, the resistance is controlled by directly saliciding the polysilicon in the trench.

Abstract: A process is provided for fabricating a transistor in which ion implantation of dopant into source/drain junctions is performed prior to defining the sidewall surfaces of a gate conductor. As such, the sidewall surfaces of the gate conductor are not subjected to damaging bombardment by ions. In one embodiment, a masking layer is patterned above a polysilicon layer dielectrically spaced above a semiconductor substrate. A S/D implant self-aligned to the sidewall surfaces of the masking layer is performed. Portions of the masking layer are removed to reduce the width of the masking layer and to form more closely spaced sidewalls. An LDD implant self-aligned to the new sidewalls of the masking layer is performed. Thereafter, the polysilicon layer is etched to define a gate conductor above and between LDD areas disposed within the substrate. In another embodiment, a sacrificial layer is patterned above a polysilicon layer dielectrically spaced above a semiconductor substrate.

Abstract: The formation of a graded passivation layer is disclosed. In one embodiment, a method includes four steps. In the first step, at least one transistor on a semiconductor substrate is provided. In the second step, at least one metallization layer is formed over the at least one transistor. In the third step, an oxide layer is deposited over the at least one metallization layer. Finally, in the fourth step, an ion implantation of a predetermined dopant is applied to create a graded passivation film over the at least one metallization layer.

Abstract: A method of making N-channel and P-channel IGFETs is disclosed.

Abstract: A semiconductor device having relatively low permittivity fluorine bearing oxide between conductive lines and a method for fabricating such a device is provided. At least two adjacent conductive lines are formed over a substrate. An oxide layer is formed between the adjacent conductive lines. A mask is formed over the oxide layer and selectively removed to expose a portion of the oxide layer between the adjacent conductive lines. A fluorine bearing species is implanted into the exposed portion of the oxide layer to reduce the permittivity of the oxide layer between the adjacent conductive lines. The permittivity or dielectric constant of the oxide layer between the adjacent conductive lines can, for example, be reduced from about 3.9 to 4.2 to about 3.0 to 3.5.

Abstract: A shallow junction MOS transistor comprising a semiconductor substrate having an upper region that includes a first and a second lightly doped region laterally displaced on either side of the channel region. The first and second lightly doped regions extend to a junction depth below the upper surface of the semiconductor substrate. A first and a second lightly doped impurity distribution are located within the first and second source/drain regions of the semiconductor substrate. The shallow junction transistor further includes a gate dielectric formed on an upper surface of the channel region of the semiconductor substrate. A conductive gate that includes a first and a second sidewall is formed on the gate dielectric. A gate insulator is formed in contact with the first and second sidewalls of the conductive gate. First and second source/drain structures are formed above the upper surface of the semiconductor substrate.

Abstract: An asymmetrical transistor, and a gate conductor used in forming that transistor, are provided. The gate conductor is formed by removing upper portions of the gate conductor along an elongated axis which the gate conductor extends. The removed portions presents a partially retained region of lesser thickness than the fully retained region immediately adjacent thereto. An implant is then forwarded to the substrate adjacent and partially below the gate conductor. Only the partially retained portions allow a subset of the originally forwarded ions to pass into the substrate to form a lightly doped drain (LDD) between the channel and the drain. The partially retained region occurs only near the drain and not adjacent the source so that the LDD area is self-aligned between the edge of the conductor and a line of demarcation separating the fully retained portion and the partially retained portion.

Abstract: An IGFET with a gate electrode in a transistor trench adjacent to an isolation trench is disclosed. The trenches are formed in a semiconductor substrate. A gate insulator is on a bottom surface of the transistor trench, insulative spacers are adjacent to opposing sidewalls of the transistor trench, and the gate electrode is on the gate insulator and spacers and is electrically isolated from the substrate. Substantially all of the gate electrode is within the transistor trench. A source and drain in the substrate are beneath and adjacent to the bottom surface of the transistor trench. The isolation trench is filled with an insulator and provides device isolation for the IGFET. Advantageously, the trenches are formed simultaneously using a single etch step.

Abstract: A wafer includes levels elevated above the wafer substrate or base substrate which includes separated substrates suitable for circuit device element formation. In one embodiment, a first level dielectric is formed over circuit devices having elements formed in the wafer substrate. Contacts from the circuit elements may extend to the surface of the first level dielectric. A second dielectric is formed on the first level dielectric and etched to create separated openings with some openings exposing contacts. The openings are filled with substrate material, thus forming elevated substrates and local interconnects where exposed contact top surfaces are present. The substrate material is suitable for circuit device fabrication. Additional levels of elevated substrates and concurrently formed local interconnects may be subsequently fabricated.

Abstract: A method of making an IGFET with a selectively doped channel region is disclosed. The method includes providing a semiconductor substrate with a device region, forming a gate over the device region, forming a masking layer that partially covers the gate and the device region, implanting a dopant into portions of the gate and the device region outside the gate that are not covered by the masking layer, transferring the dopant through the uncovered portion of the gate into a portion of an underlying channel region in the device region, thereby providing the channel region with a non-uniform lateral doping profile and adjusting a threshold voltage, and forming a source and a drain in the device region. The dopant can be implanted through the portion of the gate into the portion of the channel region, or alternatively, the dopant can be diffused from the portion of the gate into the portion of the channel region.

Abstract: A method of making an IGFET with a selectively doped gate in combination with a protected resistor includes the steps of providing a semiconductor substrate with an active region and a resistor region, forming a gate over the active region, forming a diffused resistor in the resistor region, forming an insulating layer over the active region and the resistor region, forming a masking layer over the insulating layer that includes an opening above a first portion of the gate and covers the resistor region and a second portion of the gate, applying an etch using the masking layer as an etch mask to remove the insulating layer above the first portion of the gate so that an unetched portion of the insulating layer forms a gate-protect insulator over the second portion of the gate and another unetched portion of the insulating layer forms a resistor-protect insulator over the diffused resistor, and forming a source and a drain in the active region including at least partially doping the source and the drain during

Abstract: A process is provided for producing active and passive devices on various levels of a semiconductor topography. As such, the present process can achieve device formation in three dimensions to enhance the overall density at which an integrated circuit is formed. The multi-level fabrication process not only adds to the overall circuit density but does so with emphasis placed on interconnection between devices on separate levels. Thus, high performance interconnect is introduced whereby the interconnect is made as short as possible between features within one transistor level to features within another transistor level. The interconnect achieves lower resistivity and capacitance by forming a single gate conductor which is shared by an upper level transistor and a lower level transistor. The shared gate conductor is interposed between a pair of gate dielectrics and each gate dielectric is configured between the single gate conductor and a respective substrate.