LED ARRAYS
A method of producing a light emitting diode (LED) array comprises: forming a semiconductor layer ( 100 ) of group III nitride material; forming a dielectric mask layer ( 104 ) over the semiconductor layer, the dielectric mask layer having an array of holes through it each exposing an area of the semiconductor layer; and growing an LED structure ( 108 ) in each of the holes.
1 . A method of producing a light emitting diode (LED) array, the method comprising: forming a semiconductor layer of group III nitride material; forming a dielectric mask layer over the semiconductor layer, the dielectric mask layer having an array of holes through it each exposing a respective area of the semiconductor layer; and growing an LED structure in each of the holes.
2 . The method according to claim 1 wherein the growing an LED structure in each of the holes comprises growing an n-type layer, at least one active layer, and a p-type layer in each of the holes.
3 . The method according to claim 2 wherein the dielectric mask layer has a top, and the at least one active layer has an upper surface which is below the top of the dielectric mask layer.
4 . The method according to claim 1 wherein the step of forming the dielectric mask layer comprises growing a layer of dielectric material, and etching the array of holes into the layer of dielectric material.
5 . The method according to claim 1 further comprising etching each of the exposed areas of the semiconductor layer before the growing an LED structure in each of the holes.
6 . The method according to claim 1 wherein the semiconductor layer provides a common contact to all of the LED structures.
7 . The method according to claim 1 wherein the semiconductor layer is doped.
8 . The method according to claim 1 wherein the semiconductor layer comprises a first sub-layer and a second sub-layer with a hetero-interface between the sublayers, wherein the hetero-interface is arranged to form a two dimensional charge carrier gas.
9 . The method according to claim 1 wherein the LED structures are micro-LED structures and the array is a regular array having a pitch of from 10 μm to 500 μm.
10 . The method according to claim 1 wherein the LED structures comprise a plurality of groups, the method further comprising forming a plurality of contact layer areas over the LED structures, wherein each of the contact layer areas makes electrical contact with a respective one of the groups of the LED structures.
11 . A method of producing an LED display comprising: forming a semiconductor layer of group III nitride material; forming a dielectric mask layer over the semiconductor layer, the dielectric mask layer having an array of holes through it each exposing a respective area of the semiconductor layer; and growing an LED structure in each of the holes thereby to form an LED array, and producing the LED display including the LED array.
12 . An LED array comprising a semiconductor layer, a dielectric layer extending over the semiconductor layer and having an array of holes through it, and an LED device formed in each of the holes.
13 . The LED array according to claim 12 wherein each of the LED devices comprises an n-type layer, at least one active layer, and a p-type layer.
14 . The LED array according to claim 12 wherein the dielectric layer has a top and the at least one active layer has an upper surface which is below the top of the dielectric layer.
15 . The LED array according to claim 12 wherein the semiconductor layer provides a common contact to all of the LED devices.
16 . The LED array according to claim 12 wherein the semiconductor layer is doped.
17 . The LED array according to claim 12 wherein the semiconductor layer comprises a first sub-layer and a second sub-layer with a hetero-interface between the sublayers, wherein the hetero-interface is arranged to form a two dimensional charge carrier gas.
18 . The LED array according to claim 12 wherein the LED devices are micro-LED structures and the array is a regular array having a pitch of from 10 μm to 500 μm.
19 . The LED array according to claim 12 wherein the LED devices comprise a plurality of groups and the LED array further comprises a plurality of contact layer areas extending over the LED devices, wherein each of the contact layer areas is in electrical contact with a respective one of the groups of the LED devices.
20 . An LED display comprising the LED array according to claim 12 .