Abstract:
A semiconductor structure is provided, which includes multiple sections arranged along a longitudinal axis. Preferably, the semiconductor structure comprises a middle section and two terminal sections located at opposite ends of the middle section. A semiconductor core having a first dopant concentration preferably extends along the longitudinal axis through the middle section and the two terminal sections. A semiconductor shell having a second, higher dopant concentration preferably encircles a portion of the semiconductor core at the two terminal sections, but not at the middle section, of the semiconductor structure. It is particularly preferred that the semiconductor structure is a nanostructure having a cross-sectional dimension of not more than 100 nm.
Abstract:
A method for forming carbon nanotube field effect transistors, arrays of carbon nanotube field effect transistors, and device structures and arrays of device structures formed by the methods. The methods include forming a stacked structure including a gate electrode layer and catalyst pads each coupled electrically with a source/drain contact. The gate electrode layer is divided into multiple gate electrodes and at least one semiconducting carbon nanotube is synthesized by a chemical vapor deposition process on each of the catalyst pads. The completed device structure includes a gate electrode with a sidewall covered by a gate dielectric and at least one semiconducting carbon nanotube adjacent to the sidewall of the gate electrode. Source/drain contacts are electrically coupled with opposite ends of the semiconducting carbon nanotube to complete the device structure. Multiple device structures may be configured either as a memory circuit or as a logic circuit.
Abstract:
An electronic device and method of manufacturing the device. The device includes a semiconducting region, which can be a nanowire, a first contact electrically coupled to the semiconducting region, and at least one second contact capacitively coupled to the semiconducting region. At least a portion of the semiconducting region between the first contact and the second contact is covered with a dipole layer. The dipole layer can act as a local gate on the semiconducting region to enhance the electric properties of the device.
Abstract:
A well-structure anti-punch-through microwire device and associated fabrication method are provided. The method initially forms a microwire with alternating highly and lightly doped cylindrical regions. A channel ring is formed external to the microwire outer shell and surrounding a first dopant well-structure region in the microwire, between source and drain (S/D) regions of the microwire. The S/D regions are doped with a second dopant, opposite to the first dopant. A gate dielectric ring is formed surrounding the channel ring, and a gate electrode ring is formed surrounding the gate dielectric ring. The well-structure, in contrast to conventional micro or nanowire transistors, helps prevent the punch-through phenomena.
Abstract:
The present invention is directed to methods to produce, process, and exploit nanomaterials, and particularly elongated nanowire materials. The invention provides a method for producing nanowires that includes providing a thin film of a catalyst material with varying thickness on a substrate, heating the substrate and thin film, such that the thin film disassociates at the relatively thinner regions and vapor depositing a semiconductor onto the substrate to produce nanowires. A method is also provided in which two or more thin films of different materials are overlayed over a substrate, selectively etching the first underlying thin film to create a plurality of islands of the second thin film that mask portions of the first thin film and expose other portions and growing nanowires on the first thin film. Additional methods for producing nanowires are provided.
Abstract:
The present invention relates generally to sub-microelectronic circuitry, and more particularly to nanometer-scale articles, including nanoscale wires which can be selectively doped at various locations and at various levels. In some cases, the articles may be single crystals. The nanoscale wires can be doped, for example, differentially along their length, or radially, and either in terms of identity of dopant, concentration of dopant, or both. This may be used to provide both n-type and p-type conductivity in a single item, or in different items in close proximity to each other, such as in a crossbar array. The fabrication and growth of such articles is described, and the arrangement of such articles to fabricate electronic, optoelectronic, or spintronic devices and components. For example, semiconductor materials can be doped to form n-type and p-type semiconductor regions for making a variety of devices such as field effect transistors, bipolar transistors, complementary inverters, tunnel diodes, light emitting diodes, sensors, and the like.
Abstract:
The present invention relates generally to sub-microelectronic circuitry, and more particularly to nanometer-scale articles, including nanoscale wires which can be selectively doped at various locations and at various levels. In some cases, the articles may be single crystals. The nanoscale wires can be doped, for example, differentially along their length, or radially, and either in terms of identity of dopant, concentration of dopant, or both. This may be used to provide both n-type and p-type conductivity in a single item, or in different items in close proximity to each other, such as in a crossbar array. The fabrication and growth of such articles is described, and the arrangement of such articles to fabricate electronic, optoelectronic, or spintronic devices and components. For example, semiconductor materials can be doped to form n-type and p-type semiconductor regions for making a variety of devices such as field effect transistors, bipolar transistors, complementary inverters, tunnel diodes, light emitting diodes, sensors, and the like.
Abstract:
In the method, semiconductor substrates are etched to provide nanowires, said substrates comprising a first layer of a first material and a second layer of a second material with a mutual interface, which first and second materials are different. They may be different in the doping type. Alternatively, the main constituent of the material may be different, for example SiGe or SiC versus Si, or InP versus InAs. In the resulting nanowires, the interface is atomically sharp. The electronic devices having nanowires between a first and second electrode accordingly have very good electroluminescent and optoelectronic properties.
Abstract:
A method is described for forming an element of a microelectronic circuit. A sacrificial layer is formed on an upper surface of a support layer. The sacrificial layer is extremely thin and uniform. A height-defining layer is then formed on the sacrificial layer, whereafter the sacrificial layer is etched away so that a well-defined gap is left between an upper surface of the support layer and a lower surface of the height-defining layer. A monocrystalline semiconductor material is then selectively grown from a nucleation silicon site through the gap. The monocrystalline semiconductor material forms a monocrystalline layer having a thickness corresponding to the thickness of the original sacrificial layer.
Abstract:
In the method, semiconductor substrates are etched to provide nanowires, said substrates comprising a first layer of a first material and a second layer of a second material with a mutual interface, which first and second materials are different. They may be different in the doping type. Alternatively, the main constituent of the material may be different, for example SiGe or SiC versus Si, or InP versus InAs. In the resulting nanowires, the interface is atomically sharp. The electronic devices having nanowires between a first and second electrode accordingly have very good electroluminescent and optoelectronic properties.