Abstract:
A thin film vertical light emitting diode (VLED) structure and process are described. Features of the design include the following: bonding multiple smaller diameter LED wafers to a larger diameter carrier wafer, which reduces the per LED fabrication cost; using thin film techniques to metalize the anode and cathode and using respective annealing steps prior to photolithography patterning of LED structures; enabling the thin film process by semi-permanent bonding techniques which provide thermal and chemical stability, while allowing bond release at an opportune time by thermal, optical, or chemical means; using epitaxial substrate removal techniques to separate the entire LED film from its growth substrate; and patterning various vertical LED devices which can emit light from the n-type side (cathode), p-type side (anode), side wall, or a combination of the surfaces by using mirror layers and electrically conductive and optically transmissive layers.
Abstract:
Systems and methods for fabricating nanostructures using other nanostructures as templates. A method includes mixing a dispersion and a reagent solution. The dispersion includes nanostructures such as nanowires including a first element such as copper. The reagent solution includes a second element such as silver. The second element at least partially replaces the first element in the nanostructures. The nanostructures are optionally washed, filtered, and/or deoxidized.
Abstract:
Many thousands of micro-LEDs (e.g., 25 microns per side) are deposited on a substrate. Some of the LEDs are formed to emit a peak wavelength of 450 nm (blue), and some are formed to emit a peak wavelength of 490 nm (cyan). A YAG (yellow) phosphor is then deposited on the LEDs, or a remote YAG layer is used. YAG phosphor is most efficiently excited at 450 nm and has a very weak emission at 490 nm. The two types of LEDs are GaN based and can be driven at the same current. The ratio of the two types of LEDs is controlled to achieve the desired overall color emission of the LED lamp. The blue LEDs optimally excite the YAG phosphor to produce white light having blue and yellow components, and the cyan LEDs broaden the emission spectrum to increase the CRI of the lamp while improving luminous efficiency. Other embodiments are described.
Abstract:
An exemplary printable composition of a liquid or gel suspension of diodes comprises a plurality of diodes, a first solvent and/or a viscosity modifier. An exemplary diode comprises: a light emitting or absorbing region having a diameter between about 20 and 30 microns and a height between 2.5 to 7 microns; a plurality of first terminals spaced apart and coupled to the light emitting region peripherally on a first side, each first terminal of the plurality of first terminals having a height between about 0.5 to 2 microns; and one second terminal coupled centrally to a mesa region of the light emitting region on the first side, the second terminal having a height between 1 to 8 microns.
Abstract:
The present invention provides a method of manufacturing an electronic apparatus, such as a lighting device having light emitting diodes (LEDs) or a power generating device having photovoltaic diodes. The exemplary method includes forming at least one first conductor coupled to a base; coupling a plurality of substrate particles to the at least one first conductor; converting the plurality of substrate particles into a plurality of diodes; forming at least one second conductor coupled to the plurality of spherical diodes; and depositing or attaching a plurality of substantially spherical lenses suspended in a first polymer, with the lenses and the suspending polymer having different indices of refraction. In some embodiments, the lenses and diodes have a ratio of mean diameters or lengths between about 10:1 and 2:1. In various embodiments, the forming, coupling and converting steps are performed by or through a printing process.
Abstract:
An exemplary printable composition comprises a liquid or gel suspension of a plurality of metallic nanofibers or nanowires; a first solvent; and a viscosity modifier, resin, or binder. In various embodiments, the metallic nanofibers are between about 10 microns to about 100 microns in length, are between about 10 nm to about 120 nm in diameter, and are typically functionalized with a coating or partial coating of polyvinyl pyrrolidone or a similar compound. An exemplary metallic nanofiber ink which can be printed to produce a substantially transparent conductor comprises a plurality of metallic nanofibers; one or more solvents such as 1-butanol, ethanol, 1-pentanol, n-methylpyrrolidone, cyclohexanone, cyclopentanone, 1-hexanol, acetic acid, cyclohexanol, or mixtures thereof; and a viscosity modifier, resin, or binder such as polyvinyl pyrrolidone or a polyimide, for example.
Abstract:
An exemplary printable composition comprises a liquid or gel suspension of a plurality of metallic nanofibers; a first solvent; and a viscosity modifier, resin, or binder. In various embodiments, the metallic nanofibers are between about 10 microns to about 100 microns in length, are between about 10 nm to about 120 nm in diameter, and are typically functionalized with a coating or partial coating of polyvinyl pyrrolidone or a similar compound. An exemplary metallic nanofiber ink which can be printed to produce a substantially transparent conductor comprises a plurality of metallic nanofibers; one or more solvents such as 1-butanol, ethanol, 1-pentanol, n-methylpyrrolidone, cyclohexanone, cyclopentanone, 1-hexanol, acetic acid, cyclohexanol, or mixtures thereof; and a viscosity modifier, resin, or binder such as polyvinyl pyrrolidone or a polyimide, for example.
Abstract:
An exemplary printable composition of a liquid or gel suspension of diodes comprises a plurality of diodes, a first solvent and/or a viscosity modifier. An exemplary method of fabricating an electronic device comprises: depositing one or more first conductors; and depositing a plurality of diodes suspended in a mixture of a first solvent and a viscosity modifier. Various exemplary diodes have a lateral dimension between about 10 to 50 microns and about 5 to 25 microns in height. Other embodiments may also include a plurality of substantially chemically inert particles having a range of sizes between about 10 to about 50 microns.
Abstract:
An exemplary printable composition of a liquid or gel suspension of diodes comprises a plurality of diodes, a first solvent and/or a viscosity modifier. In other exemplary embodiments a second solvent is also included, and the composition has a viscosity substantially between about 100 cps and about 25,000 cps at about 25° C. In an exemplary embodiment, a composition comprises: a plurality of diodes or other two-terminal integrated circuits; one or more solvents comprising about 15% to 99.9% of any of N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, N-octanol, ethanol, tetrahydrofurfuryl alcohol, cyclohexanol, and mixtures thereof; a viscosity modifier comprising about 0.10% to 2.5% methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof; and about 0.01% to 2.5% of a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 50 microns.
Abstract:
The various embodiments of the invention provide an addressable or a static emissive display comprising a plurality of layers, including a first substrate layer, wherein each succeeding layer is formed by printing or coating the layer over preceding layers. Exemplary substrates include paper, plastic, rubber, fabric, glass, ceramic, or any other insulator or semiconductor. In an exemplary embodiment, the display includes a first conductive layer attached to the substrate and forming a first plurality of conductors; various dielectric layers; an emissive layer; a second, transmissive conductive layer forming a second plurality of conductors; a third conductive layer included in the second plurality of conductors and having a comparatively lower impedance; and optional color and masking layers. Pixels are defined by the corresponding display regions between the first and second plurality of conductors. Various embodiments are addressable, have a substantially flat form factor with a thickness of 1-3 mm, and are also scalable virtually limitlessly, from the size of a mobile telephone display to that of a billboard.