Abstract: Quantum dots and methods of making quantum dots are described. A method begins with forming quantum dots having a core-shell structure with a plurality of ligands on the shell structure. The method includes exchanging the plurality of ligands with a plurality of second ligands. The plurality of second ligands have a weaker binding affinity to the shell structure than the plurality of first ligands. The plurality of second ligands are then exchanged with hydrolyzed alkoxysilane to form a monolayer of hydrolyzed alkoxysilane on a surface of the shell structure. The method includes forming a barrier layer around the shell structure by using the hydrolyzed alkoxysilane as a nucleation center.

Abstract: Doped semiconductor ink formulations, methods of making doped semiconductor ink formulations, methods of coating or printing thin films, methods of forming electronic devices and/or structures from the thin films, and methods for modifying and controlling the threshold voltage of a thin film transistor using the films are disclosed. A desired dopant may be added to an ink formulation comprising a Group IVA compound and a solvent, and then the ink may be printed on a substrate to form thin films and conductive structures/devices, such as thin film transistors. By adding a customized amount of the dopant to the ink prior to printing, the threshold voltage of a thin film transistor made from the doped semiconductor ink may be independently controlled upon activation of the dopant.

Abstract: Highly luminescent nanostructures, particularly highly luminescent quantum dots, are provided. The nanostructures have high photoluminescence quantum yields and in certain embodiments emit light at particular wavelengths and have a narrow size distribution. The nanostructures can comprise ligands, including C5-C8 carboxylic acid ligands employed during shell formation and/or dicarboxylic or polycarboxylic acid ligands provided after synthesis. Processes for producing such highly luminescent nanostructures are also provided, including methods for enriching nanostructure cores with indium and techniques for shell synthesis.

Abstract: Printable dopant formulations, methods of making such dopant formulations, and methods of using such dopant formulations are disclosed. The dopant formulations provide a printable dopant ink with a viscosity sufficient to prevent ink spreading when deposited in a pattern on a substrate. Furthermore, an ion exchange purification process provides the dopant formulation with a reduced metal ion concentration, and thus a relatively high purity level. Consequently, the dopant residue remaining on the substrate after curing and/or dopant activation process is relatively uniform, and therefore can be easily removed.

Abstract: In one aspect, the present invention provides undoped and doped siloxanes, germoxanes, and silagermoxanes that are substantially free from carbon and other undesired contaminants. In a second aspect, the present invention provides methods for making such undoped and doped siloxanes, germoxanes, and silagermoxanes. In still another aspect, the present invention provides compositions comprising undoped and/or doped siloxanes, germoxanes, and silagermoxanes and a solvent, and methods for forming undoped and doped dielectric films from such compositions. Undoped and/or doped siloxane compositions as described advantageously provide undoped and/or doped dielectric precursor inks that may be employed in forming substantially carbon-free undoped and/or doped dielectric films.

Abstract: Highly luminescent nanostructures, particularly highly luminescent quantum dots, are provided. The nanostructures have high photoluminescence quantum yields and in certain embodiments emit light at particular wavelengths and have a narrow size distribution. The nanostructures can comprise ligands, including C5-C8 carboxylic acid ligands employed during shell formation and/or dicarboxylic or polycarboxylic acid ligands provided after synthesis. Processes for producing such highly luminescent nanostructures are also provided, including methods for enriching nanostructure cores with indium and techniques for shell synthesis.

Abstract: Highly luminescent nanostructures, particularly highly luminescent quantum dots, are provided. The nanostructures have high photoluminescence quantum yields and in certain embodiments emit light at particular wavelengths and have a narrow size distribution. The nanostructures can comprise ligands, including C5-C8 carboxylic acid ligands employed during shell formation and/or dicarboxylic or polycarboxylic acid ligands provided after synthesis. Processes for producing such highly luminescent nanostructures are also provided, including methods for enriching nanostructure cores with indium and techniques for shell synthesis.

Abstract: Highly luminescent nanostructures, particularly highly luminescent quantum dots, are provided. The nanostructures have high photoluminescence quantum yields and in certain embodiments emit light at particular wavelengths and have a narrow size distribution. The nanostructures can comprise ligands, including C5-C8 carboxylic acid ligands employed during shell formation and/or dicarboxylic or polycarboxylic acid ligands provided after synthesis. Processes for producing such highly luminescent nanostructures are also provided, including methods for enriching nanostructure cores with indium and techniques for shell synthesis.

Abstract: Highly luminescent nanostructures, particularly highly luminescent quantum dots, are provided. The nanostructures have high photoluminescence quantum yields and in certain embodiments emit light at particular wavelengths and have a narrow size distribution. The nanostructures can comprise ligands, including C5-C8 carboxylic acid ligands employed during shell formation and/or dicarboxylic or polycarboxylic acid ligands provided after synthesis. Processes for producing such highly luminescent nanostructures are also provided, including methods for enriching nanostructure cores with indium and techniques for shell synthesis.

Abstract: Embodiments relate to printing features from an ink containing a material precursor. In some embodiments, the material includes an electrically active material, such as a semiconductor, a metal, or a combination thereof. In another embodiment, the material includes a dielectric. The embodiments provide improved printing process conditions that allow for more precise control of the shape, profile and dimensions of a printed line or other feature. The composition(s) and/or method(s) improve control of pinning by increasing the viscosity and mass loading of components in the ink. An exemplary method thus includes printing an ink comprising a material precursor and a solvent in a pattern on the substrate; precipitating the precursor in the pattern to form a pinning line; substantially evaporating the solvent to form a feature of the material precursor defined by the pinning line; and converting the material precursor to the patterned material.

Abstract: Compositions and methods for controlled polymerization and/or oligomerization of silane (and optionally cyclosilane) compounds, including those of the general formulae SinH2n and SinH2n+2, as well as halosilanes and arylsilanes, to produce soluble polysilanes, polygermanes and/or polysilagermanes having low levels of carbon and metal contaminants, high molecular weights, low volatility, high purity, high solubility and/or high viscosity. The polysilanes, polygermanes and/or polysilagermanes are useful as a precursor to silicon- and/or germanium-containing conductor, semiconductor and dielectric films.

Abstract: Heterocyclosilane compounds and methods for making the same. Such compounds (and/or ink compositions containing the same) are useful for printing or spin coating a doped silane film onto a substrate that can easily be converted into a doped amorphous silicon film (that may also be hydrogenated to some extent) or doped polycrystalline semiconductor film suitable for electronic devices. Thus, the present invention advantageously provides commercial qualities and quantities of doped semiconductor films from a “doped liquid silicon” composition.

Abstract: Dopant-group substituted (cyclo)silane compounds, liquid-phase compositions containing such compounds, and methods for making the same. Such compounds (and/or ink compositions containing the same) are useful for printing or spin coating a doped silane film onto a substrate that can easily be converted into a doped amorphous or polycrystalline silicon film suitable for electronic devices. Thus, the present invention advantageously provides commercial qualities and quantities of doped semiconductor films from a doped “liquid silicon” composition.

Abstract: Highly luminescent nanostructures, particularly highly luminescent quantum dots, are provided. The nanostructures have high photoluminescence quantum yields and in certain embodiments emit light at particular wavelengths and have a narrow size distribution. The nanostructures can comprise ligands, including C5-C8 carboxylic acid ligands employed during shell formation and/or dicarboxylic or polycarboxylic acid ligands provided after synthesis. Processes for producing such highly luminescent nanostructures are also provided, including methods for enriching nanostructure cores with indium and techniques for shell synthesis.

Abstract: Embodiments relate to printing features from an ink containing a material precursor. In some embodiments, the material includes an electrically active material, such as a semiconductor, a metal, or a combination thereof. In another embodiment, the material includes a dielectric. The embodiments provide improved printing process conditions that allow for more precise control of the shape, profile and dimensions of a printed line or other feature. The composition(s) and/or method(s) improve control of pinning by increasing the viscosity and mass loading of components in the ink. An exemplary method thus includes printing an ink comprising a material precursor and a solvent in a pattern on the substrate; precipitating the precursor in the pattern to form a pinning line; substantially evaporating the solvent to form a feature of the material precursor defined by the pinning line; and converting the material precursor to the patterned material.

Abstract: A method of making hydrogenated Group IVA compounds having reduced metal-based impurities, compositions and inks including such Group IVA compounds, and methods for forming a semiconductor thin film. Thin semiconducting films prepared according to the present invention generally exhibit improved conductivity, film morphology and/or carrier mobility relative to an otherwise identical structure made by an identical process, but without the washing step. In addition, the properties of the present thin film are generally more predictable than those of films produced from similarly prepared (cyclo)silanes that have not been washed according to the present invention.

Abstract: Doped semiconductor ink formulations, methods of making doped semiconductor ink formulations, methods of coating or printing thin films, methods of forming electronic devices and/or structures from the thin films, and methods for modifying and controlling the threshold voltage of a thin film transistor using the films are disclosed. A desired dopant may be added to an ink formulation comprising a Group IVA compound and a solvent, and then the ink may be printed on a substrate to form thin films and conductive structures/devices, such as thin film transistors. By adding a customized amount of the dopant to the ink prior to printing, the threshold voltage of a thin film transistor made from the doped semiconductor ink may be independently controlled upon activation of the dopant.

Abstract: Polysilanes, inks containing the same, and methods for their preparation are disclosed. The polysilane may have the formula H-[(AHR)n(c-AmHpm-2)q]—H, where A is independently Si or Ge; R is H, -AaHa+1Ra, halogen, aryl or substituted aryl; (n+a)?10 if q=0, q?3 if n=0, and (n+q)?6 if both n and q?0; p is 1 or 2; and m is from 3 to 12. The method may include combining a silane compound of the formula AHaR14-a, AkHgR1?h and/or c-AmHpmR1rm with a catalyst of the formula R4xR5yMXz (or an immobilized derivative thereof) to form a poly(aryl)silane; then washing the poly(aryl)silane with an aqueous washing composition and contacting the poly(aryl)silane with an adsorbent to remove the metal M. Alternatively, the method may include halogenating a polyarylsilane and reducing the halopolysilane with a metal hydride to form the polysilane.

Abstract: Methods for forming doped silane and/or semiconductor thin films, doped liquid phase silane compositions useful in such methods, and doped semiconductor thin films and structures. The composition is generally liquid at ambient temperatures and includes a Group IVA atom source and a dopant source. By irradiating a doped liquid silane during at least part of its deposition, a thin, substantially uniform doped oligomerized/polymerized silane film may be formed on a substrate. Such irradiation is believed to convert the doped silane film into a relatively high-molecular weight species with relatively high viscosity and relatively low volatility, typically by cross-linking, isomerization, oligomerization and/or polymerization. A film formed by the irradiation of doped liquid silanes can later be converted (generally by heating and annealing/recrystallization) into a doped, hydrogenated, amorphous silicon film or a doped, at least partially polycrystalline silicon film suitable for electronic devices.

Abstract: A method of making hydrogenated Group IVA compounds having reduced metal-based impurities, compositions and inks including such Group IVA compounds, and methods for forming a semiconductor thin film. Thin semiconducting films prepared according to the present invention generally exhibit improved conductivity, film morphology and/or carrier mobility relative to an otherwise identical structure made by an identical process, but without the washing step. In addition, the properties of the present thin film are generally more predictable than those of films produced from similarly prepared (cyclo)silanes that have not been washed according to the present invention.