Abstract: The present application provides nitride semiconductor nanoparticles, for example nanocrystals, made from a new composition of matter in the form of a novel compound semiconductor family of the type group II-III-N, for example ZnGaN, ZnInN, ZnInGaN, ZnAlN, ZnAlGaN, ZnAlInN and ZnAlGaInN. This type of compound semiconductor nanocrystal is not previously known in the prior art. The invention also discloses II-N semiconductor nanocrystals, for example ZnN nanocrystals, which are a subgroup of the group II-III-N semiconductor nanocrystals. The composition and size of the new and novel II-III-N compound semiconductor nanocrystals can be controlled in order to tailor their band-gap and light emission properties. Efficient light emission in the ultraviolet-visible-infrared wavelength range is demonstrated.

Abstract: A method of producing nitride nanoparticles comprises reacting at least one organometallic compound, for example an alkyl metal, with at least one source of nitrogen. The reaction may involve one or more liquid phase organometallic compounds, or may involve one or more liquid phase organometallic compounds dissolved in a solvent or solvent mixture. The reaction constituents may be heated to a desired reaction temperature (for example in the range 40° C. to 300° C.).

Abstract: A method of producing nitride nanoparticles comprises reacting at least one organometallic compound, for example an alkyl metal, with at least one source of nitrogen. The reaction may involve one or more liquid phase organometallic compounds, or may involve one or more liquid phase organometallic compounds dissolved in a solvent or solvent mixture. The reaction constituents may be heated to a desired reaction temperature (for example in the range 40° C. to 300° C.).

Abstract: The present application provides nitride semiconductor nanoparticles, for example nanocrystals, made from a new composition of matter in the form of a novel compound semiconductor family of the type group II-III-N, for example ZnGaN, ZnInN, ZnInGaN, ZnAlN, ZnAlGaN, ZnAlInN and ZnAlGaInN. This type of compound semiconductor nanocrystal is not previously known in the prior art. The invention also discloses II-N semiconductor nanocrystals, for example ZnN nanocrystals, which are a subgroup of the group II-III-N semiconductor nanocrystals. The composition and size of the new and novel II-III-N compound semiconductor nanocrystals can be controlled in order to tailor their band-gap and light emission properties. Efficient light emission in the ultraviolet-visible-infrared wavelength range is demonstrated.

Abstract: The present application provides nitride semiconductor nanoparticles, for example nanocrystals, made from a new composition of matter in the form of a novel compound semiconductor family of the type group II-III-N, for example ZnGaN, ZnInN, ZnInGaN, ZnAlN, ZnAlGaN, ZnAlInN and ZnAlGaInN. This type of compound semiconductor nanocrystal is not previously known in the prior art. The invention also discloses II-N semiconductor nanocrystals, for example ZnN nanocrystals, which are a subgroup of the group II-III-N semiconductor nanocrystals. The composition and size of the new and novel II-III-N compound semiconductor nanocrystals can be controlled in order to tailor their band-gap and light emission properties. Efficient light emission in the ultraviolet-visible-infrared wavelength range is demonstrated.

Abstract: A light source is provided for use in a treatment device for treating a fluid, solid or surface. The light source includes a light emitting diode that emits a first component of ultraviolet (UV) light, and a UV laser light source that emits a second component of UV light having a peak wavelength different from a peak wavelength of the first component of UV light. The first component of UV light and the second component of UV light are applied to treat the fluid or surface. The UV laser light source may include a laser light source and a frequency doubling component that receives light from the laser light source and converts the light to the second component of UV light. A treatment device includes the described light source and a container containing the fluid, or a solid surface, to be treated.

Abstract: A system and method are disclosed for the simultaneous optical disinfection and detection of biological particles in a flowing fluid, such as air or water, medium. A light source for irradiating the flowing medium is a dual wavelength laser element simultaneously emitting a visible laser beam and an ultraviolet laser beam. In particular, a laser diode may generate a first visible laser light beam, and a second ultraviolet laser light beam may be generated by passing the first laser light beam through a frequency doubling crystal. Optical detectors measure scattering, fluorescence and/or transmission of the laser light beams from the air or water medium to determine the presence of biological particles in real-time.

Abstract: A method of manufacturing a semiconductor device comprises depositing a semiconductor layer over a semiconductor surface having at least one first region with a first (average surface lattice) parameter value and at least one second region having a second parameter value different from the first. The semiconductor layer is deposited to a thickness so self-organized islands form over both the first and second regions. The difference in the parameter value means the islands over the first region have a first average parameter value and the islands over the second region have a second average parameter value different from the first. A capping layer is deposited over islands and has a greater forbidden bandgap than the islands whereby the islands form quantum dots, which have different properties over the first and second regions due to difference(s) between the first and second region islands.

Abstract: A method for growing an In(x)Al(y)Ga(1?x?y)N layer (where x is greater than zero and less than or equal to one, y is greater than or equal to zero and less than or equal to one and the sum of x and y is less than or equal to one). The method includes supplying plasma-activated nitrogen atoms as a source of nitrogen for the In(x)Al(y)Ga(1?x?y)N layer to a growth surface, where a flux of the plasma-activated nitrogen atoms supplied to the growth surface is at least four times higher than a total flux of aluminium and gallium atoms also supplied to the growth surface, where either the aluminium or gallium flux may or may not be zero; and simultaneously supplying indium atoms and nitrogen-containing molecules to the growth surface.

Abstract: A laminated substrate system containing a metamorphic transition region (2) made from multiple and alternating layers of AlxGa1-xN (5) and the supporting substrate material (4) (or a material having the same general chemical composition thereto). A III-Nitrides semiconductor device (2) with a low dislocation density is formed on top of the laminated substrate system. The multiple layers (4,5) of the metamorphic transition region form a superlattice structure whose lattice constant and structure changes along its growth direction from that of the supporting substrate (1) (in the vicinity of the supporting substrate) to that of the device (3) (in the vicinity of the device).

Abstract: The present application provides nitride semiconductor nanoparticles, for example nanocrystals, made from a new composition of matter in the form of a novel compound semiconductor family of the type group II-III-N, for example ZnGaN, ZnInN, ZnInGaN, ZnAlN, ZnAlGaN, ZnAlInN and ZnAlGaInN. This type of compound semiconductor nanocrystal is not previously known in the prior art. The invention also discloses II-N semiconductor nanocrystals, for example ZnN nanocrystals, which are a subgroup of the group II-III-N semiconductor nanocrystals. The composition and size of the new and novel II-III-N compound semiconductor nanocrystals can be controlled in order to tailor their band-gap and light emission properties. Efficient light emission in the ultraviolet-visible-infrared wavelength range is demonstrated.

Abstract: The present application provides a new composition of matter in the form of a new compound semiconductor family of the type group Zn-(II)-III-N, where III denotes one or more elements in Group III of the periodic table and (II) denotes one or more optional further elements in Group II of the periodic table. Members of this family include for example, ZnGaN, ZnInN, ZnInGaN, ZnAlN, ZnAlGaN, ZnAlInN or ZnAlGaInN. This type of compound semiconductor material is not previously known in the prior art. The composition of the new Zn-(II)-III-N compound semiconductor material can be controlled in order to tailor its band-gap and light emission properties. Efficient light emission in the ultraviolet-visible-infrared wavelength range is demonstrated. The products of this invention are useful as constituents of optoelectronic devices such as solar cells, light emitting diodes, laser diodes and as a light emitting phosphor material for LEDs and emissive EL displays.

Abstract: An InGaAsN solar cell includes an InGaAsN structure having a bandgap between 1.0 eV to 1.05 eV, and a depletion region width of at least 1.0 ?m.

Abstract: A method of manufacturing a nitride semiconductor structure includes disposing a semiconductor substrate in a molecular beam epitaxy reactor; growing a wetting layer comprising AlxInyGa(1?(x+y))As(0?x+y?1) or AlxInyGa(1?(x+y))P(0?x+y?1) on the substrate; in-situ annealing the wetting layer; growing a first AlGaInN layer on the wetting layer using plasma activated nitrogen as the source of nitrogen with an additional flux of phosphorous or arsenic; and growing a second AlGaInN layer on the first AlGaInN layer using ammonia as a source of nitrogen.

Abstract: A nitride semiconductor device comprises: a layer structure including an active region (102) containing AlxGayIn1-x-yN quantum dots layers (102a), and means (104a,104b) for applying an electric field across the active region to modify the spin orientation of excitons in the quantum dots. The exciton spin lifetime at 300K is, for at least a range of values of the electric field applied across the active region, at least 1 ns, more preferably at least 10 ns, and particularly preferably at least 15 ns or 20 ns. These lifetimes may be obtained by configuring the device such that the exciton binding energy is, for at least a range of values of the electric field applied across the active region, 25 meV or greater.

Abstract: A semiconductor light-emitting device fabricated in the (Al,Ga,In)N materials system has an active region for light emission (3) comprising InGaN quantum dots or InGaN quantum wires. An AlGaN layer (6) is provided on a substrate side of the active region. This increases the optical output of the light-emitting device. This increased optical output is believed to result from the AlxGa1-xN layer serving, in use, to promote the injection of carriers into the active region.

Abstract: A photon source includes a substrate, an active region formed above the substrate, and a pair of electrodes configured to provide an injection current which passes through the active region. The active region includes a quantum dot layer including one or more AlyGaxIn1-x-yN quantum dots, where 0?x?1 and 0?y?<1, and an AlInN current confinement layer adjacent the quantum dot layer. The current confinement layer has an aperture which defines a low resistance path for the injection current to flow through the active region between the pair of electrodes. The quantum dot layer includes less than 50 quantum dots within the aperture as projected onto the quantum dot layer.

Abstract: A method of manufacturing a nitride semiconductor structure includes disposing a semiconductor substrate in a molecular beam epitaxy reactor; growing a wetting layer comprising AlxInyGa(1?(x/y))As(0?x+y?1) or AlxInyGa(1?(x/y))P(0?x+y?1) on the substrate; in-situ annealing the wetting layer; growing a first AlGaInN layer on the wetting layer using plasma activated nitrogen as the source of nitrogen with an additional flux of phosphorous or arsenic; and growing a second AlGaInN layer on the first AlGaInN layer using ammonia as a source of nitrogen.

Abstract: A semiconductor device includes an AlxGayIn1-x-yN layer and (Al,Ga,In)N quantum dots disposed on the AlxGayIn1-x-yN layer, wherein the indium fraction in the AlxGayIn1-x-yN layer is non-zero (1-x-y?0).

Abstract: A method of MBE growth of a semiconductor layer structure comprises growing a first (Al,Ga)N layer (step 13) over a substrate at the first substrate temperature (T1) using ammonia as the nitrogen precursor. The substrate is then cooled (step 14) to a second-substrate temperature (T2) which is lower than the first substrate temperature. An (In,Ga)N quantum well structure is then grown (step 15) over the first (Al,Ga)N layer by MBE using ammonia as the nitrogen precursor. The supply of ammonia to the substrate is maintained continuously during the first growth step, the cooling step, and the second growth step. After completion of the growth of the (In,Ga)N quantum well structure, the substrate may be heated to a third temperature (T3) which is greater than the second substrate temperature (T2). A second (Al,Ga)N layer is then grown over the (In,Ga)N quantum well structure (step 17).