摘要:
Disclosed is an integrated circuit with multiple semiconductor fins having different widths and variable spacing on the same substrate. The method of forming the circuit incorporates a sidewall image transfer process using different types of mandrels. Fin thickness and fin-to-fin spacing are controlled by an oxidation process used to form oxide sidewalls on the mandrels, and more particularly, by the processing time and the use of intrinsic, oxidation-enhancing and/or oxidation-inhibiting mandrels. Fin thickness is also controlled by using sidewalls spacers combined with or instead of the oxide sidewalls. Specifically, images of the oxide sidewalls alone, images of sidewall spacers alone, and/or combined images of sidewall spacers and oxide sidewalls are transferred into a semiconductor layer to form the fins. The fins with different thicknesses and variable spacing can be used to form a single multiple-fin FET or, alternatively, various single-fin and/or multiple-fin FETs.
摘要:
Disclosed are a silicon control rectifier, a method of making the silicon control rectifier and the use of the silicon control rectifier as an electrostatic discharge protection device of an integrated circuit. The silicon control rectifier includes a silicon body formed in a silicon layer in direct physical contact with a buried oxide layer of a silicon-on-insulator substrate, a top surface of the silicon layer defining a horizontal plane; and an anode of the silicon control rectifier formed in a first region of the silicon body and a cathode of the silicon control rectifier formed in an opposite second region of the silicon body, wherein a path of current flow between the anode and the cathode is only in a single horizontal direction parallel to the horizontal plane.
摘要:
A method of forming a self-aligned SOI diode, the method comprising depositing a protective structure over a substrate; implanting a plurality of diffusion regions of variable dopant types in an area between at least one pair of isolation regions in the substrate, the plurality of diffusion regions separated by a diode junction, wherein the implanting aligns an upper surface of the diode junction with the protective structure; and removing the protective structure. The method further comprises forming a silicide layer over the diffusion regions and aligned with the protective structure. The protective structure comprises a hard mask, wherein the hard mask comprises a silicon nitride layer. Alternatively, the protective structure comprises a polysilicon gate and insulating spacers on opposite sides of the gate. Furthermore, in the removing step, the spacers remain on the substrate.
摘要:
A semiconductor structure, and associated method of fabrication, comprising a substrate having a continuous buried oxide layer and having a plurality of trench isolation structures. The buried oxide layer may be located at more than one depth within the substrate. The geometry of the trench isolation structure may vary with depth. The trench isolation structure may touch or not touch the buried oxide layer. Two trench isolation structures may penetrate the substrate to the same depth or to different depths. The trench isolation structures provide insulative separation between regions within the substrate and the separated regions may contain semiconductor devices. The semiconductor structure facilitates the providing of digital and analog devices on a common wafer. A dual-depth buried oxide layer facilitates an asymmetric semiconductor structure.
摘要:
A semiconductor memory device comprising: an SOI substrate having a thin silicon layer on top of a buried insulator; and an SRAM comprising four NFETs and two PFETs located in the thin silicon layer, each the NFET and PFET having a body region between a source region and a drain region, wherein the bodies of two of the NFETs are electrically connected to ground. Additionally, the bodies of the two PFETs are electrically connected to VDD.
摘要:
A process for forming heterogeneous silicide structures on a semiconductor substrate (10) includes implanting molybdenum ions into selective areas of the semiconductor substrate (10) to form molybdenum regions (73, 74, 75, 76). Titanium is then deposited over the semiconductor substrate (10). The semiconductor substrate (10) is annealed at a temperature between approximately 600° C. and approximately 700° C. During the annealing process, the titanium deposited in areas outside the molybdenum regions (73, 74, 75, 76) interacts with silicon on the substrate to form titanium silicide in a high resistivity C49 crystal phase. The titanium deposited in areas within the molybdenum regions (73, 74, 75, 76) interacts with silicon to form titanium silicide in a low resistivity C54 crystal phase because the presence of molybdenum ions in silicon lowers the energy barrier for crystal phase transformation between the C49 phase and the C54 phase.
摘要:
A domino logic circuit having a clocked precharge is disclosed. The domino logic circuit includes a precharge transistor, an isolation transistor, and multiple evaluate transistors. Connected to a power supply, the precharge transistor receives a clock input. The isolation transistor is connected to ground and also receives the clock input. Each of the input transistors, which are coupled between the precharge transistor and the isolation transistor, receives a signal input. The gate dielectric thickness of the evaluate transistors is less than the gate dielectric thickness of the precharge transistor.
摘要:
Silicon is formed at selected locations on a substrate during fabrication of selected electronic components. A dielectric separation region is formed within the top silicon layer, and filled with a thermally conductive material. A liner material may be optionally deposited prior to depositing the thermally conductive material. In a second embodiment, a horizontal layer of thermally conductive material is also deposited in an oxide layer or bulk silicon layer below the top layer of silicon.
摘要:
A high voltage tolerant diode structure for mixed-voltage, and mixed signal and analog/digital applications. The preferred silicon diode includes a polysilicon gate structure on at least one dielectric film layer on a semiconductor (silicon) layer or body. A well or an implanted area is formed in a bulk semiconductor substrate or in a surface silicon layer on an SOI wafer. Voltage applied to the polysilicon gate film, electrically depletes it, reducing voltage stress across the dielectric film. An intrinsic polysilicon film may be counter-doped, implanted with a low doped implantation, implanted with a low doped source/drain implant, or with a low doped MOSFET LDD or extension implant. Alternatively, a block mask may be formed over the gate structure when defining the depleted-polysilicon gate silicon diode to form low series resistance diode implants, preventing over-doping the film. Optionally, a hybrid photoresist method may be used to form higher doped edge implants in the silicon to reduce diode series resistance without a block mask.
摘要:
A circuit element comprising a semiconductor substrate. A well region of a first conductivity type is formed in a surface of the substrate. A dielectric film is formed on the substrate. A gate conductor of the first conductivity type is formed on the dielectric film over the well region of the substrate. The gate conductor is formed of a polycrystalline silicon film. The gate conductor has an impurity concentration substantially lower than a standard impurity concentration for the gate conductor of an MOS device. A polycrystalline silicon edge spacer is formed on each side of the gate conductor. A first pair of first conductivity type impurity diffusion regions are formed adjacent to the polycrystalline silicon edge spacers. The polycrystalline silicon film and edge spacers lie on a portion of the substrate between the first pair of first conductivity type impurity diffusion regions. The first pair of first conductivity type impurity diffusion regions have an impurity concentration substantially lower than the standard impurity concentration for the gate conductor of an MOS device. The gate conductor and the first pair of first conductivity type impurity diffusion regions may be formed by a single implantation step. Applications include ESD protection, analog applications, peripheral input/output circuitry, decoupling capacitors, and resistor ballasting.