202 results about "Group ii" patented technology

Matrixes doped with semiconductor nanocrystals are provided. In certain embodiments, the semiconductor nanocrystals have a size and composition such that they absorb or emit light at particular wavelengths. The nanocrystals can comprise ligands that allow for mixing with various matrix materials, including polymers, such that a minimal portion of light is scattered by the matrixes. The matrixes of the present invention can also be utilized in refractive index matching applications. In other embodiments, semiconductor nanocrystals are embedded within matrixes to form a nanocrystal density gradient, thereby creating an effective refractive index gradient. The matrixes of the present invention can also be used as filters and antireflective coatings on optical devices and as down-converting layers. Processes for producing matrixes comprising semiconductor nanocrystals are also provided. Nanostructures having high quantum efficiency, small size, and/or a narrow size distribution are also described, as are methods of producing indium phosphide nanostructures and core-shell nanostructures with Group II-VI shells.

Disclosed herein is a graded core/shell semiconductor nanorod having at least a first segment of a core of a Group II-VI, Group III-V or a Group IV semiconductor, a graded shell overlying the core, wherein the graded shell comprises at least two monolayers, wherein the at least two monolayers each independently comprise a Group II-VI, Group III-V or a Group IV semiconductor.

A compound semiconductor material for forming an active layer of a thin film transistor device is disclosed, which has a group II-VI compound doped with a dopant ranging from 0.1 to 30 mol %, wherein the dopant is selected from a group consisting of alkaline-earth metals, group IIIA elements, group IVA elements, group VA elements, group VIA elements, and transitional metals. The method for forming an active layer of a thin film transistor device by using the compound semiconductor material of the present invention is disclosed therewith.

The present invention discloses thin film photovoltaic devices comprising Group II-VI semiconductor layers with a substrate configuration having an interface layer between the absorber layer and the window layer to create improved junctions.

The present invention also discloses methods for making and surface treatments for thin film photovoltaic devices comprising Group II-VI semiconductor layers with a substrate configuration to create devices with improved junctions.

This invention provides methods for fabricating substantially continuous layers of a group III nitride semiconductor material having low defect densities and optionally having a selected crystal polarity. The methods include epitaxial growth nucleating and/or seeding on the upper portions of a plurality of pillars/islands of a group III nitride material that are irregularly arranged on a template structure. The upper portions of the islands have low defect densities and optionally have a selected crystal polarity. The invention also includes template structures having a substantially continuous layer of a masking material through which emerge upper portions of the pillars/islands. The invention also includes such template structures. The invention can be applied to a wide range of semiconductor materials, both elemental semiconductors, e.g., combinations of Si (silicon) with strained Si (sSi) and/or Ge (germanium), and compound semiconductors, e.g., group II-VI and group III-V compound semiconductor materials.

A semiconductor nanocrystal composition that is stable and has high luminescent quantum yield. The semiconductor nanocrystal composition has a semiconductor nanocrystal core of a group II alloyed I-III-VI semiconductor nanocrystal material. A method of making a semiconductor nanocrystal composition is also provides which includes synthesizing a semiconductor nanocrystal core of a group II alloyed I-III-VI semiconductor material.

The present invention relates to a dissolvable article in the form of a porous dissolvable solid structure, comprising from about 10% to about 50% water soluble polymer; from about 1% to about 25% plasticizer; from about 23% to about 75% surfactant; wherein said surfactants comprise one or more surfactants from Group I, wherein Group I includes anionic surfactants, and one or more surfactants from Group II, wherein Group II includes a surfactant selected from the group consisting of amphoteric, zwitterionic and combinations thereof; wherein the ratio of Group I to Group II surfactants is from about 5:95 to about 30:70; and wherein said dissolvable article has a density of from about 0.05 g/cm3 to about 0.40 g/cm3.

The invention relates to methods for preparing 3-element semiconductor nanocrystals of the formula WY_xZ_(1-x), wherein W is a Group II element, Y and Z are different Group VI elements, and 0<X<1, comprising dissolving a Group II element, a first Group VI element, and a second Group VI element in a one or more solvents. The Group II, VI and VI elements are combined to provide a II:VI:VI SCN precursor solution, which is heated to a temperature sufficient to produce semiconductor nanocrystals of the formula WY_xZ_(1-x). The solvent used to dissolve the Group II element comprises octadecene and a fatty acid. The solvent used to dissolve the Group VI elements comprises octadecene. The invention also includes semiconductor nanocrystals prepared according to the disclosed methods, as well as methods of using the semiconductor nanocrystals.

A method of making a semiconductor comprises depositing a group II-group VI compound onto a substrate in the presence of nitrogen using sputtering to produce a nitrogen-doped semiconductor. This method can be used for making a photovoltaic cell using sputtering to apply a back contact layer of group II-group VI compound to a substrate in the presence of nitrogen, the back coating layer being doped with nitrogen. A semiconductor comprising a group II-group VI compound doped with nitrogen, and a photovoltaic cell comprising a substrate on which is deposited a layer of a group II-group VI compound doped with nitrogen, are also included.

Semiconductor devices containing group II-VI semiconductor materials are disclosed. The devices may include a p-n junction containing a p-type group II-VI semiconductor material and an n-type semiconductor material. The p-type group II-VI semiconductor includes a single crystal group II-VI semiconductor containing atoms of group II elements, atoms of group VI elements, and one or more p-type dopants. The p-type dopant concentration is greater than about 10¹⁶ atoms·cm⁻³, the semiconductor resistivity is less than about 0.5 ohm·cm, and the carrier mobility is greater than about 0.1 cm²/V·s. The semiconductor devices may include light emitting diodes, laser diodes, field effect transistors, and photodetectors.

The present invention provides nanoparticles having a core/shell structure consisting of a core comprising a Group III element and a Group V element at a molar ratio of the Group III element to the Group V element in the range of 1.25 to 3.0, and a shell comprising a Group II element and a Group VI element and having a thickness of 0.2 nm to 4 nm, the nanoparticles having a photoluminescence efficiency of 10% or more and a diameter of 2.5 to 10 nm; a method of producing the water-dispersible nanoparticles comprising bringing a dispersion of III-V semiconductor nanoparticles in an organic solvent into contact with an aqueous solution of a Group II element-containing compound and a Group VI element-containing compound to thereby transfer the III-V semiconductor nanoparticles of the organic solvent dispersion to the aqueous solution, and then irradiating the aqueous solution with light; and a method of producing a glass matrix having the nanoparticles dispersed therein.

The present invention provides III-V semiconductor nanoparticles having a high photoluminescence efficiency in an aqueous solution, and a method of producing the nanoparticles. The invention further provides a fluorescent material with high PL efficiency containing the III-V semiconductor nanoparticles retained in a glass matrix, a method of producing the fluorescent material, and a light-emitting device containing the fluorescent material.

A doping method for forming quantum dots is disclosed, which includes following steps: providing a first precursor solution for a group II element and a second precursor solution for a group VI element; heating and mixing the first precursor solution and the second precursor solution for forming a plurality of II-VI compound cores of the quantum dots dispersing in a melting mixed solution; and injecting a third precursor solution for a group VI element and a forth precursor solution with at least one dopant to the mixed solution in turn at a fixed time interval in order to form quantum dots with multi-shell dopant; wherein the dopant described here is selected from a group consisting of transitional metal and halogen elements. This method of the invention can dope the dopants in the inner quantum dot and enhance the emission intensity efficiently.

The present invention provides novel compounds of the formula Gei-x-ySixSny, wherein 0.01<y<0.11, and 0.26<x<0.35, and semiconductor structures comprising such compounds. The present invention also provides novel semiconductor structures comprising silicon substrates, an SiGe buffer layer, and a Group III-V or II-VI active layer. The present invention also provides novel semiconductor structures comprising silicon substrates, an SiGe buffer layer, an SiGeSn template layer, and an SiGe, Ge, Group III-V, or Group II-VI active layer.

A plurality of metal interconnects incorporating a Group II element alloy for protecting the metal interconnects and method to form and incorporate the Group II element alloy are described. In one embodiment, a Group II element alloy is used as a seed layer, or a portion thereof, which decreases the line resistance and increases the mechanical strength of a metal interconnect. In another embodiment, a Group II element alloy is used to form a barrier layer, which, in addition to decreasing the line resistance and increasing the mechanical integrity, also increases the chemical integrity of a metal interconnect.

This invention provides methods for fabricating substantially continuous layers of group III nitride semiconductor materials having low defect densities. The methods include epitaxial growth of nucleation layers on a base substrate, thermally treatment of said nucleation layer and epitaxial growth of a discontinuous masking layer. The methods outlined promote defect reduction through masking, annihilation and coalescence, therefore producing semiconductor structures with low defect densities. The invention can be applied to a wide range of semiconductor materials, both elemental semiconductors, e.g., combinations of Si (silicon) with strained Si (sSi) and/or Ge (germanium), and compound semiconductors, e.g., group II-VI and group III-V compound semiconductor materials.

Group II metal MOCVD precursor compositions are described having utility for MOCVD of the corresponding Group II metal-containing films. The complexes are Group II metal beta-diketonate adducts of the formula M(beta-diketonate)2(L)4 wherein M is the Group II metal and L is tetrahydrofuran. Such source reagent complexes of barium and strontium are usefully employed in the formation of barium strontium titanate and other Group II thin films on substrates for microelectronic device applications, such as integrated circuits, ferroelectric memories, switches, radiation detectors, thin-film capacitors, microelectromechanical structures (MEMS) and holographic storage media.

The invention provides an analgesic and refreshing herbal composition useful as dentrifrices, said composition comprising 50-60% Wt. of betle extract (from Piper betle leaves); 40-50% Wt. of one or more group I essential oil selected from Levender officinal, Dementholised oil (ex-Mentha arvensis), Fennel oil and Ocimum gratissimum; 3.5-6% Wt. of one or more group II essential oils and their isolates selected from Ocimum Sanctum, Pulegone (ex Mentha pulegonium), Carvone (ex. Dill seed) and Menthol (ex. Mentha arvensis); 1-5% Wt. of one or more group III essential oils selected from Camphor, turpentine oil, Cedarwood oil and Safrole oil, along with 0.5-2% Wt. of Thymol and 0.25-1% Wt. of preservative/antioxidant, and a process for preparing the composition.

Methods of forming a nanocrystal are provided. The nanocrystal may be a binary nanocrystal of general formula M1A or of general formula M1O, a ternary nanocrystal of general formula M1M2A, of general formula M1AB or of general formula M1M2O or a quaternary nanocrystal of general formula M1M2AB. M1 is a metal of Groups II-IV, Group VII or Group VIII of the PSE. A is an element of Group VI or Group V of the PSE. O is oxygen. A homogenous reaction mixture in a non-polar solvent of low boiling point is formed, that includes a metal precursor containing the metal M1 and, where applicable M2. For an oxygen containing nanocrystal the metal precursor contains an oxygen donor. Where applicable, A is also included in the homogenous reaction mixture. The homogenous reaction mixture is under elevated pressure brought to an elevated temperature that is suitable for forming a nanocrystal.

Commercially viable methods of manufacturing p-type group II–VI semiconductor materials are disclosed. A thin film of group II–VI semiconductor atoms is deposited on a self supporting substrate surface. The semiconductor material includes atoms of group II elements, group VI elements, and one or more p-type dopants. The semiconductor material may be deposited on the substrate surface under deposition conditions in which the group II atoms, group VI atoms, and p-type dopant atoms are in a gaseous phase prior to combining as the thin film. Alternatively, a liquid deposition process may be used to deposit the group II atoms, group VI atoms, and p-type dopant atoms in a predetermined orientation to result in the fabrication of the group II–VI semiconductor material. The resulting semiconductor thin film is a persistent p-type semiconductor, and the p-type dopant concentration is greater than about 10¹⁶ atoms·cm⁻³. The semiconductor resistivity is less than about 0.5 ohm·cm.

A persistent p-type group II-VI semiconductor material is disclosed. The group II-VI semiconductor includes atoms of group II elements, atoms of group VI elements, and one or more p-type dopants. The p-type dopant concentration is sufficient to render the group II-VI semiconductor material in a single crystal form. The semiconductor resistivity is less than about 0.5 ohm·cm, and the carrier mobility is greater than about 0.1 cm²/V·s. Group II elements include zinc, cadmium, the alkaline earth metals such as beryllium, magnesium calcium, strontium, and barium, and mixtures thereof. Group VI elements include oxygen, sulfur, selenium, tellurium, and mixtures thereof. P-type dopants include, but are not limited to, nitrogen, phosphorus, arsenic, antimony, bismuth, copper, chalcogenides of the foregoing, and mixtures thereof.

The present invention relates to a method of making non-spherical semiconductor nanocrystals. This method involves providing a reaction mixture containing a first precursor compound, a solvent, and a surfactant, where the first precursor compound has a Group II or a Group IV element and contacting the reaction mixture with a pure noble metal nanoparticle seed. The reaction mixture is heated. A second precursor compound having a Group VI element is added to the heated reaction mixture under conditions effective to produce non-spherical semiconductor nanocrystals. Non-spherical semiconductor nanocrystals and nanocrystal populations made by the above method are also disclosed.

The invention discloses a high-efficiency cluster type water pump system with constant pressure and variable flow and an operation control method. According to the high-efficiency cluster type water pump system, a water pump can be reasonably configured according to the constant pressure and water consumption continuous change rule of industrial and mining enterprises. The high-efficiency cluster type water pump system comprises a plurality of water pumps, a full-voltage bus, two frequency converting buses, two frequency converters and a plurality of normally-opened alternating current contactors, wherein one water pump is a speed regulating pump and other water pumps are constant speed pumps; each water pump is provided with a driving motor; the driving motors are divided into a group I and a group II; each driving motor in two groups is connected with the full-voltage bus, a frequency converting bus I and a frequency converting bus II through contacts of the two alternating current contactors; a frequency converter I and a frequency converter II are respectively connected between the full-voltage bus and the frequency converting bus II as between the frequency converting bus I and the frequency converting bus II through contacts of another two alternating current contactors; and one residual contact of the alternating current contactor is connected between the two frequency converting buses. The control process comprises a start process of the water pumps, the speed regulating operation process of a variable speed pump, a flexible switching process of the water pumps and the speed regulating operation process of the variable speed pump after the flexible switching process is ended.