2199 results about "Charge carrier mobility" patented technology

In electronic displays or imaging units, the control of pixels is achieved by an array of transistors. These transistors are in a thin film form and arranged in a two-dimensional configuration to form switching circuits, driving circuits or even read-out circuits. In this invention, thin film transistors and circuits with indium oxide-based channel layers are provided. These thin film transistors and circuits may be fabricated at low temperatures on various substrates and with high charge carrier mobilities. In addition to conventional rigid substrates, the present thin film transistors and circuits are particularly suited for the fabrication on flexible and transparent substrates for electronic display and imaging applications. Methods for the fabrication of the thin film transistors with indium oxide-based channels are provided.

A thin film transistor, which is capable of improving carrier mobility, and a display device and an electronic device, each of which uses the thin film transistor, are provided. The thin film transistor includes: a gate electrode; an oxide semiconductor layer including a multilayer film including a carrier travel layer configuring a channel and a carrier supply layer for supplying carriers to the carrier travel layer; a gate insulating film provided between the gate electrode and the oxide semiconductor layer; and a pair of electrodes as a source and a drain. A conduction band minimum level or a valence band maximum level corresponding to a carrier supply source of the carrier supply layer is higher in energy than a conduction band minimum level or a valence band maximum level corresponding to a carrier supply destination of the carrier travel layer.

A graphene layer is formed on a surface of a silicon carbide substrate. A dummy gate structure is formed over the fin, in the trench, or on a portion of the planar graphene layer to implant dopants into source and drain regions. The dummy gate structure is thereafter removed to provide an opening over the channel of the transistor. Threshold voltage adjustment implantation may be performed to form a threshold voltage implant region directly beneath the channel, which comprises the graphene layer. A gate dielectric is deposited over a channel portion of the graphene layer. After an optional spacer formation, a gate conductor is formed by deposition and planarization. The resulting graphene-based field effect transistor has a high carrier mobility due to the graphene layer in the channel, low contact resistance to the source and drain region, and optimized threshold voltage and leakage due to the threshold voltage implant region.

An electronic device, and SRAM and a method of forming the electronic device and SRAM. The semiconductor device including: a pass gate transistor having a fin body having opposing sidewalls aligned in a first direction and having a first majority carrier mobility and a gate adjacent to both sidewalls of the fin body; a pull down latch transistor having a fin body having opposing sidewalls aligned in a second direction and having a second majority carrier mobility and a gate adjacent to both sidewalls of thc fin body; a pull up latch transistor having a fin body having opposing sidewalls aligned in a third direction and having a third majority carrier mobility and a gate adjacent to both sidewalls of the fin body; and CMOS chevron logic circuits, wherein crystal planes of each fin body and of CMOS transistor of the chevron logic are co-aligned.

The present invention provides a device design and method for forming the same that results in Fin Field Effect Transistors having different gains without negatively impacting device density. The present invention forms relatively low gain FinFET transistors in a low carrier mobility plane and relatively high gain FinFET transistors in a high carrier mobility plane. Thus formed, the FinFETs formed in the high mobility plane have a relatively higher gain than the FinFETs formed in the low mobility plane. The embodiments are of particular application to the design and fabrication of a Static Random Access Memory (SRAM) cell. In this application, the bodies of the n-type FinFETs used as transfer devices are formed along the {110} plane. The bodies of the n-type FinFETs and p-type FinFETs used as the storage latch are formed along the {100}. Thus formed, the transfer devices will have a gain approximately half that of the n-type storage latch devices, facilitating proper SRAM operation

In producing complementary sets of metal-oxide-semiconductor (CMOS) field effect transistors, including nMOS and pMOS transistors), carrier mobility is enhanced or otherwise regulated through the use of layering various stressed films over either the nMOS or pMOS transistor (or both), depending on the properties of the layer and isolating stressed layers from each other and other structures with an additional layer in a selected location. Thus both types of transistors on a single chip or substrate can achieve an enhanced carrier mobility, thereby improving the performance of CMOS devices and integrated circuits.

MOS transistors having localized stressors for improving carrier mobility are provided. Embodiments of the invention comprise a gate electrode formed over a substrate, a carrier channel region in the substrate under the gate electrode, and source/drain regions on either side of the carrier channel region. The source/drain regions include an embedded stressor having a lattice spacing different from the substrate. In a preferred embodiment, the substrate is silicon and the embedded stressor is SiGe or SiC. An epitaxy process that includes using HCl gas selectively forms a stressor layer within the crystalline source/drain regions and not on polycrystalline regions of the structure. A preferred epitaxy process dispenses with the source/drain hard mask required of conventional methods. The embedded SiGe stressor applies a compressive strain to a transistor channel region. In another embodiment, the embedded stressor comprises SiC, and it applies a tensile strain to the transistor channel region.

The present invention provides structures and methods for a transistor formed on a V-shaped groove. The V-shaped groove contains two crystallographic facets joined by a ridge. The facets have different crystallographic orientations than what a semiconductor substrate normally provides such as the substrate orientation or orientations orthogonal to the substrate orientation. Unlike the prior art, the V-shaped groove is formed self-aligned to the shallow trench isolation, eliminating the need to precisely align the V-shaped grooves with lithographic means. The electrical properties of the new facets, specifically, the enhanced carrier mobility, are utilized to enhance the performance of transistors. In a transistor with a channel on the facets that are joined to form a V-shaped profile, the current flows in the direction of the ridge joining the facets avoiding any inflection in the direction of the current.

A semiconductor structure having improved carrier mobility is provided. The semiconductor structures includes a hybrid oriented semiconductor substrate having at least two planar surfaces of different crystallographic orientation, and at least one CMOS device located on each of the planar surfaces of different crystallographic orientation, wherein each CMOS device has a stressed channel. The present invention also provides methods of fabricating the same. In general terms, the inventive method includes providing a hybrid oriented substrate having at least two planar surfaces of different crystallographic orientation, and forming at least one CMOS device on each of the planar surfaces of different crystallographic orientation, wherein each CMOS device has a stressed channel.

Enhanced carrier mobility in transistors of differing (e.g. complementary) conductivity types is achieved on a common chip by provision of two or more respective stressed layers, such as etch stop layers, overlying the transistors with stress being wholly or partially relieved in portions of the respective layers, preferably by implantations with heavy ions such as germanium, arsenic, xenon, indium, antimony, silicon, nitrogen oxygen or carbon in accordance with a block-out mask. The distribution and small size of individual areas of such stressed structures also prevents warping or curling of even very thin substrates.

The carrier mobility in transistor channel regions of Si—Ge devices is increased by employing a stressed liner. Embodiments include applying a high compressive or tensile stressed film overlying relaxed source/drain regions. Other embodiments include applying a high compressively or high tensilely stressed film, after post silicide spacer removal, over gate electrodes and strained Si source/drain regions of P-channel or N-channel transistors, respectively.

A method of manufacturing three-dimensional semiconductor device, comprising the steps of: forming a stack structure of a plurality of a first material layers and a second material layers on a substrate in the memory cell region; etching said stack structure to form a plurality of trenches; forming channel layers in said plurality of trenches; performing annealing treatment to at least one surface of the channel layers to reduce the surface roughness and the interface state. In accordance with the three-dimensional semiconductor device manufacturing method of the present invention, the formation of interface states is depressed by introducing a dummy channel sacrificial layer for the interface treatment on the channel surface and back surface, and/or the channel surface roughness is reduced by introducing a buffer layer on the channel surface and back surface during the treatment, which can improve the channel carrier mobility, improve the channel current as well as the reliability of the memory cell.

Embodiments of the invention provide structures and methods for forming a strained MOS transistor. A preferred embodiment includes creating a compressive strain in a PMOS transistor for improving carrier mobility without the need for source/drain recess formation and SiGe epitaxy. Embodiments comprise forming a gate electrode on a silicon substrate, and forming a lightly doped source/drain (LDS/LDD) region in the substrate by simultaneously implanting germanium and boron in the substrate using the gate electrode as a mask. Embodiments further comprise forming spacers on opposite sidewalls of the gate electrode and forming a heavily doped source/drain region in the substrate by simultaneously implanting germanium and boron using the gate electrode and the spacers as a mask. Embodiments may further include annealing the semiconductor device to recrystallize SiGe.

Channel depth in a field effect transistor is limited by an intra-layer structure including a discontinuous film or layer formed within a layer or substrate of semiconductor material. Channel depth can thus be controlled much in the manner of SOI or UT-SOI technology but with less expensive substrates and greater flexibility of channel depth control while avoiding floating body effects characteristic of SOI technology. The profile or cross-sectional shape of the discontinuous film may be controlled to an ogee or staircase shape to improve short channel effects and reduce source/drain and extension resistance without increase of capacitance. Materials for the discontinuous film may also be chosen to impose stress on the transistor channel from within the substrate or layer and provide increased levels of such stress to increase carrier mobility. Carrier mobility may be increased in combination with other meritorious effects.

A silicon-on-insulator (SOI) device and structure having locally strained regions in the silicon active layer formed by increasing the thickness of underlying regions of a buried insulating layer separating the silicon active layer from the substrate. The stress transferred from the underlying thickened regions of the insulating layer to the overlying strained regions increases carrier mobility in these confined regions of the active layer. Devices formed in and on the silicon active layer may benefit from the increased carrier mobility in the spaced-apart strained regions.

A strained channel MOSFET device with improved charge mobility and method for forming the same, the method including providing a first gate with a first semiconductor conductive type and second gate with a semiconductor conductive type on a substrate; forming a first strained layer with a first type of stress on said first gate; and, forming a second strained layer with a second type of stress on said second gate.