Abstract:
PROBLEM TO BE SOLVED: To prevent dopant impurities in a gate electrode from diffusing through a gate insulator. SOLUTION: A multifaceted gate MOSFE device includes: a strained Si-based monocrystalline strip 510 which has a center part and two end parts and has multifaceted channel regions 511 and 512 in the center part and has a source and a drain 540 in the end parts; gate insulators 520 and 530 covering the channel regions; a gate 500 which overlays at least two faces of the channel regions 511 and 512 and interfaces with the gate insulators; supporting platforms 590 and 595 which are engaged with the strained Si-based monocrystalline strip by bonding means. The gate includes a first layer 500 disposed on top faces of the gate insulators, and the first layer comprises a Si:C or SiGe:C. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a field effect transistor (FET) with a channel formed by a semiconductor nanowire (semiconductor nanowire channel) and doped semiconductor source and drain regions. SOLUTION: A FET structure with a semiconductor nanowire forming the FET channel and doped source and drain regions formed by radial epitaxy from the semiconductor nanowire body is disclosed. A top gated and a bottom gated nanowire FET structures are discussed. The source and drain fabrication can use either selective or non-selective epitaxy. COPYRIGHT: (C)2008,JPO&INPIT
Abstract:
A strained crystalline layer having a tensilely strained SiGe portion and a compressively strained SiGe portion is disclosed. The strained crystalline layer is epitaxially bonded, or grown, on top of a SiGe relaxed buffer layer, in a way that the tensilely strained SiGe has a Ge concentration below that of the SiGe relaxed buffer, and the compressively strained SiGe has a Ge concentration above that of the SiGe relaxed buffer. The strained crystalline layer and the relaxed buffer can reside on top a semi-insulator substrate or on top of an insulating divider layer. In some embodiments the tensile SiGe layer is pure Si, and the compressive SiGe layer is pure Ge. The tensilely strained SiGe layer is suited for hosting electron conduction type devices and the compressively strained SiGe is suited for hosting hole conduction type devices. The strained crystalline layer is capable to seed an epitaxial insulator, or a compound semiconductor layer.
Abstract:
A structure and method of fabrication for PMOS devices in a compressively strained Ge layer is disclosed. The fabrication method of such devices is compatible with standard CMOS technology and it is fully scalable. The processing includes selective epitaxial depositions of an over 50% Ge content buffer layer, a pure Ge layer, and a SiGe top layer. Fabricated buried channel PMOS devices hosted in the compressively strained Ge layer show superior device characteristics relative to similar Si devices.
Abstract:
PROBLEM TO BE SOLVED: To provide a metal-insulator-semiconductor field effect transistor (MISFET) composed of a conductive channel in which no hetero-barrier exists in the flowing direction of currents and a heterojunction between the source/drain and main body (bulk) of the transistor. SOLUTION: The structures of the strained vertical channel of the field effect transistor in which a drain region, main body region, and source region are incorporated in the side wall of a vertical single-crystal semiconductor structure, the field effect transistor, and a CMOS circuit and the forming methods of the channel, transistor, and circuit are described. The heterojunction is formed between the source and main body of the field effect transistor and the source region and vertical channel independently form lattice strains to the main body region. The drain region contains a carbon-doped region to prevent the diffusion of a dopant (boron) into the main body region. When this invention is used, the problem about the leakage current from the source region due to the heterojunction and lattice strains is reduced. Apart from the leakage current, a lattice strain can be formed in a channel region for increasing mobility by selecting the semiconductor material. COPYRIGHT: (C)2005,JPO&NCIPI
Abstract:
PROBLEM TO BE SOLVED: To provide an insulated-gate semiconductor field effect transistor (MISFET) composed of a conductive channel in which no hetero-barrier exists in the flowing direction of currents and a heterojunction between the source/drain and main body (bulk) of the transistor. SOLUTION: The structures of the vertical channel 165 of the field effect transistor in which a drain region 162, main body region 163, and source region 164 are incorporated in the side wall of a vertical single-crystal semiconductor structure, the field effect transistor, and a CMOS circuit and the forming methods of the channel, transistor, and circuit are described. The heterojunction is formed between the source and main body of the transistor and the source region 164 and vertical channel 165 independently form lattice stains to the main body region 163. The drain region 162 contains a carbon-doped region to prevent the diffusion of dopants (namely, boron (B) and phosphorus (P)) into the main body region 163. COPYRIGHT: (C)2005,JPO&NCIPI
Abstract:
PROBLEM TO BE SOLVED: To provide a method of forming a SiGe bipolar transistor substantially excluding dislocation defects present between an emitter and collector region. SOLUTION: This forming method includes the steps of: (a) providing a structure including at least a bipolar device region, wherein the bipolar device region includes at least a first conductive type collector region 52 formed in a semiconductor substrate; (b) making a SiGe base region 54 deposit on the collector region, wherein carbon is continuously grown over the whole collector region and the whole SiGe base region during deposition; and (c) forming the emitter region 56 patterned on the SiGe base region. COPYRIGHT: (C)2008,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To form buried oxide regions below regions of a single crystal semiconductor layer, by selecting a single crystal Si substrate, and forming a first SiGe epitaxial layer having a const. or gradient and first oxidation rate on the top face of the substrate. SOLUTION: A single crystal Si or SiGe substrate is selected, a first Si1-x Gex or (Si1-x Gex )a C1-a epitaxial layer 16 having a const. or gradient is formed on the top face 15 of the substrate 14 and has a first oxidation rate at specified temp. and ambient condition. The ambient condition includes O, water vapor or HCl or both. The const. or gradient compsn. of the epitaxial layer 16 needs the epitaxial growth, even if the lattice consts. of the layers 14 and 16 differ, and is selected so as to have the first oxidation rate.
Abstract:
PROBLEM TO BE SOLVED: To provide a superconducting structure, having a gate conformed with the conventional Si technology which enables or invalidate the superconduction state by changing the gate voltage to change the electron-to-hole ratio. SOLUTION: A structure which allows superconducting current to flow comprises a substrate, a first epitaxial p-type semiconductor layer 24 subjected to a compression strain for transferring 12, 14, 20 holes, a second epitaxial barrier layer 30 on the first layer, and a third epitaxial n-type semiconductor layer 32 subjected to a tensile strain for transferring electrons. The barrier layer 30 has sufficient thickness to limit the recombination of electrons but is sufficiently thin to form electron-hole pairs, due to the attraction between the electron and hole. The first and second layers has SiGe, e.g. Si1-x Gex , where x=0.6-0.8 for the first layer and x=0.3-0.4 for the second layer and third layer has Si.
Abstract:
PROBLEM TO BE SOLVED: To provide an advanced FET device preventing dopant impurities from passing through a gate insulator and being diffused. SOLUTION: A layer structure of a MOSFET (metal oxide semiconductor field effect transistor) has a layer of Si:C or SiGe:C sandwiched between a gate insulator and a layer in which impurities are doped to have a preselected work function. Further, the present invention includes the above and an improvement of other FET devices, for example a drain and a source of protrusion shapes, a multi-facet gate-on insulator, and a MODFET (modulation dope FET). COPYRIGHT: (C)2005,JPO&NCIPI