Abstract: An active matrix LED array precursor forming a precursor to a micro LED array is provided. The active matrix LED array precursor comprises a common first semiconducting layer comprising a substantially undoped Group III-nitride, a plurality of transistor-driven LED precursors, and a common source contact. Each transistor-driven LED precursor comprises a monolithic light emitting diode (LED) structure comprising a plurality of III-nitride semiconducting layers, a barrier semiconducting layer, and a gate contact. Each monolithic LED structure is formed on a portion of the common semiconducting layer. The barrier semiconducting is layer formed on a portion of the common semiconducting layer encircling the LED structure and configured to induce a two-dimensional electron channel layer at the interface between the common semiconducting layer and the barrier semiconducting layer. The gate contact is formed over a portion of the two-dimensional electron channel layer, the gate contact encircling the LED structure.

Abstract: An LED backlight for use with a display panel, the backlight comprising a monolithic LED array having a surface and comprising a plurality of LEDs for emitting light from the surface of the array; a monolithic collimator array comprising a plurality of collimating channels, and being aligned so that each of the collimating channels is aligned with one or more of the plurality of LEDs, wherein the collimating channels are configured to collimate emitted light emitted from the LEDs to angles in the range of about +/?50° from a line substantially normal to the surface of the LED array; a microlens array for focusing the collimated light to infinity, the microlens array comprising a plurality of lenslets, each lenslet aligned with a collimating channel of the monolithic collimator array; and a relay lens for focusing the light from the microlens array on a display panel.

Abstract: According to the first aspect of the disclosure, a method of forming a light emitting device array precursor is provided. The method comprises forming a first light emitting layer on a first substrate, forming an array of first light emitting devices from the first light emitting layer, each first light emitting device configured to emit light having a first wavelength. A first bonding layer is formed on the first light emitting layer. A second light emitting layer is formed on a second substrate, the second light emitting layer configured to emit light having a second wavelength different to the first wavelength. A second bonding layer is formed on the second light emitting layer. The second bonding layer is bonded to a handling substrate, followed by removing the second substrate from the second light emitting layer. A third bonding layer is formed on the second light emitting layer on an opposite side of the second light emitting layer to the handling layer.

Abstract: A pixel comprising a first sub-pixel. The first sub-pixel comprises an LED layer comprising a light-emitting material configured to emit pump light having a pump wavelength. A container layer has a container surface comprising a first container aperture that defines a first container volume extending through the container layer. A first colour converting layer provided in the first container volume is configured to receive pump light from the LED layer and emit first converted light of a first converted wavelength. A first lens is provided on the container layer over the first container aperture, having an outer side that comprises a first convex surface. A first reflector conforming to the first convex surface comprises a first reflector configured to reflect light at the pump wavelength and transmit light at the first converted wavelength; and a second reflector configured to reflect light at both the pump wavelength and the first converted wavelength.

Abstract: A method of manufacturing a LED precursor and a LED precursor is provided. The LED precursor is manufactured by forming a monolithic growth stack having a growth surface and forming a monolithic LED stack on the growth surface. The monolithic growth stack comprises a first semiconducting layer comprising a Group III-nitride, a second semiconducting layer, and third semi-conducting layer. The second semiconducting layer comprises a first Group III-nitride including a donor dopant such that the second semiconducting layer has a donor density of at least 5×1018 cm-3. The second semiconducting layer has an areal porosity of at least 15% and a first in-plane lattice constant. The third semiconducting layer comprises a second Group III-nitride different to the first Group-III-nitride.

Abstract: A light emitting device array is provided. The light emitting device array comprises a light emitting stack, a first electrical contact layer, an array of second electrical contacts, and an anti-reflection layer. The light emitting stack has a light emitting surface and a contact surface. The light emitting surface and the contact surface define opposing sides of the light emitting stack. The light emitting stack comprises a plurality of Group III-nitride layers including a first semiconducting layer provided towards the light emitting surface of the light emitting stack, a second semiconducting layer provided towards the contact surface, and an active layer arranged between the first semiconducting layer and the second semiconducting layer, the active layer configured to generate light having a first wavelength. The light emitting surface and the contact surface are parallel to each other and aligned with the plurality of Group III-nitride layers.

Abstract: A method for fabricating a frusto-conical micro-lightguide for collimation of light emitted from micro-LEDs. The method comprises depositing a layer of UV-curable material onto a substrate. A first part of the layer is selectively cured using UV light having a conical irradiation profile to define a shape of the frusto-conical micro-lightguide. The UV-curable material is developed to remove one of the first part of the layer and a second part of the layer, wherein the second part of the layer is uncured.

Abstract: A micro-LED of improved emission efficiency and collimation is provided. The micro-LED (100) comprises: a mesa substrate (110) including a recess (111); and a semiconductor material (120) provided on the recess, comprising a first surface (121) adjacent the mesa substrate, a second surface (122) opposite the first surface, and a light emission region (126) configured to emit light in response to application of an electrical current. The second surface comprises a convex surface (127). Light emitted by the light emission region incident on the convex surface is transmitted through the convex surface if an angle of incidence to the normal of the convex surface is smaller than a critical angle, and is refracted upon transmission through the convex surface. The light emission region (126) is located proximate the focal plane of the convex surface (127). An area of the light emission region is smaller than a cross-sectional area of the convex surface in a plane parallel to the light emission region.

Abstract: A method of forming a plurality of monolithic light emitting diode (LED) pixels (1) for a LED display is provided. The method comprises forming a common (102) semiconducting layer comprising a Group III-nitride on a sacrificial substrate and forming n array of light emitting diode (LED) subpixels on a surface of the common semiconducting layer. The method further includes forming a planarising dielectric layer on the array of LED subpixels. The array of the LED subpixels is divided into a plurality of monolithic LED pixels by etching a grid of pixel defining trenches to the sacrificial substrate, wherein each monolithic LED pixel comprises at least two LED subpixels. A sacrificial dielectric layer is formed on the pixel trenches to form a bonding surface. A handling substrate is bonded to the bonding surface, wherein first portions of the sacrificial substrate are selectively removed for separating each of the monolithic LED pixels.

Abstract: The present invention provides a monolithic LED array precursor comprising a plurality of LED structures, an LED device comprising the monolithic LED array, and a method of manufacture thereof. In particular, the present disclosure provides a monolithic LED array having improved light emission.

Abstract: A method of forming and testing a plurality of monolithic electronic devices is provided. As part of the method a monolithic device array comprising Group III-nitrides is formed on a sacrificial substrate. A test substrate comprising electrical contacts is aligned with electrical contacts of the monolithic device array and bonded to the monolithic device array via bonding dielectric layers. Power is supplied from the test substrate to test the monolithic devices of the monolithic device array. Portions of the sacrificial substrate are then selectively removed to separate each of the monolithic electronic devices, wherein a sacrificial dielectric layer is removed to separate each monolithic electronic device from the test substrate.

Abstract: A method of forming a Light Emitting Diode (LED) precursor is provided. The method comprises forming a LED stack comprising a plurality of Group III-nitride layers on a substrate, the LED stack comprising a LED stack surface formed on an opposite side of the LED stack to the substrate, and masking a first portion of the LED stack surface, leaving a second portion of the LED stack surface exposed. The second portion of the LED stack surface is subjected to a resistivity changing process such that a second region of the LED stack below the second portion of the LED stack surface comprising at least one of the Group III-nitride layers of the LED stack has a relatively higher resistivity than a resistivity of the respective Group-III nitride layer in a first region of the LED stack below the first portion of the LED stack surface.

Abstract: A method of forming a monolithic LED precursor is provided. The method comprises: providing a substrate having a top surface; forming a first semiconductor layer comprising a Group III-nitride on the top surface of the substrate; selectively masking the first semiconductor layer with a LED mask layer, the LED mask layer comprising an aperture defining a LED well through a thickness of the LED mask layer to an unmasked portion of the first semiconductor layer, the LED well comprising LED well sidewalls extending from a top surface of the first semiconductor layer to a top surface of the LED mask layer; and selectively forming a monolithic LED stack within the LED well on the unmasked portion of the first semiconductor layer.

Abstract: A method of preparing a substrate for substrate bonding is provided. The method comprises: forming a recess in a substrate surface of the substrate, and forming a bondable dielectric layer on the substrate surface of the substrate. The bondable dielectric layer has a bonding surface on an opposite side of the bondable dielectric layer to the substrate surface, wherein the recess and the bondable dielectric layer define a dielectric cavity having a dielectric cavity volume. A plug is formed configured to make electrical contact to the substrate in the dielectric cavity volume. The plug has a plug volume which is less than the dielectric cavity volume, wherein the plug extends from the dielectric cavity beyond the bonding surface in a direction generally normal to the bonding surface. The plug is coined by compressing the substrate between opposing planar surfaces such that a contact surface of the plug is made co-planar with the bonding surface.

Abstract: A Light Emitting Diode (LED) precursor and a method of forming a LED precursor is provided. The LED precursor comprises a first semiconducting layer and a monolithic LED structure provided on a growth surface of the first semiconducting layer. The first semiconducting layer comprises Group III-nitrides. The first semiconducting layer includes a mesa structure extending from a major surface of the first semiconducting layer to define a growth surface including a bulk semiconductor surface and a mesa surface. The first semiconducting layer comprises a first semiconducting sublayer comprising a Group III nitride having a first in-plane lattice constant, and a strain-relaxed sublayer. The strain relaxed sublayer comprises a Group III-nitride provided across the first semiconducting sublayer, wherein the strain relaxed sublayer provides the mesa surface of the mesa structure, such that the mesa surface has a second in-plane lattice constant which is larger than the first in-plane lattice constant.

Abstract: A Light Emitting Diode (LED) array precursor is provided. The LED array precursor comprises a substrate having a substrate surface, a first LED stack, a p++ layer, a n++ layer and a second LED stack. The first LED stack is provided on a first portion of the substrate surface. The first LED stack comprises a plurality of first Group III-nitride layers defining a first semiconductor junction configured to output light having a first wavelength wherein a n-type side of the first semiconductor junction is orientated towards the substrate surface. The p++ layer is provided on the first LED stack, the p++ layer comprising a Group III-nitride. The n++ layer has a first portion covering the p++ layer of the first LED stack and a second portion covering a second portion of the substrate surface, wherein a tunnel junction is formed at an interface between the n++ layer and the p++ layer, the n++ layer comprising a Group III-nitride.

Abstract: A method of forming a Light Emitting Diode (LED) precursor comprising: forming a first semiconducting layer comprising a Group III-nitride on a substrate, selectively removing a portion of the first semiconducting layer to form a mesa structure, and forming a monolithic LED structure. According to the method, the first semiconducting layer has a growth surface on an opposite side of the first semiconducting layer to the substrate. According to the method, the first semiconducting layer is selectively removed to form the mesa structure such that the growth surface of the first semiconducting layer comprises a mesa surface and a bulk semiconducting surface.

Abstract: A light emitting diode is provided having a LED layer configured to emit pump light having a pump light wavelength from a light emitting surface, the LED layer comprising a plurality of Group III-nitride layers. A container layer is provided on the light emitting surface of the LED layer, the container surface including an opening defining a container volume through the container layer to the light emitting surface of the LED layer. A colour converting layer is provided in the container volume, the colour converting Got layer configured to absorb pump light and emit converted light of a converted light wavelength longer than the pump light wavelength. A lens is provided on the container surface over the opening, the lens having a convex surface on an opposite side of the lens to the colour converting layer. A pump light reflector laminate provided over the convex surface of the lens the pump light reflector laminate having a stop-band configured to reflect the pump light centred on a first wavelength.

Abstract: A light emitting diode (LED) precursor is provided. The LED precursor comprises a substrate (10), an LED structure (30) comprising a plurality of Group III-nitride layers, and a passivation layer (40). The LED structure comprises a p-type semiconductor layer (36), an n-type semiconductor layer (32), and an active layer (34) between the p-type and n-type semiconductor layers. Each of the plurality of Group III-nitride layers comprises a crystalline Group III-nitride. The LED structure has a sidewall (37) which extends in a plane orthogonal to a (0001) crystal plane of the Group III-nitride layers. The passivation layer is provided on the sidewall of the LED structure such that the passivation layer covers the active layer. The passivation layer comprises a crystalline Group III-nitride with a bandgap higher than a bandgap of the active layer.

Abstract: An active matrix LED array precursor forming a precursor to a micro LED array is provided. The active matrix LED array precursor comprises a common first semiconducting layer comprising a substantially undoped Group III-nitride, a plurality of transistor-driven LED precursors, and a common source contact. Each transistor-driven LED precursor comprises a monolithic light emitting diode (LED) structure comprising a plurality of III- nitride semiconducting layers, a barrier semiconducting layer, and a gate contact. Each monolithic LED structure is formed on a portion of the common semiconducting layer. The barrier semiconducting is layer formed on a portion of the common semiconducting layer encircling the LED structure and configured to induce a two-dimensional electron channel layer at the interface between the common semiconducting layer and the barrier semiconducting layer. The gate contact is formed over a portion of the two-dimensional electron channel layer, the gate contact encircling the LED structure.