OPTICALLY TRANSPARENT ADHESION LAYER TO CONNECT NOBLE METALS TO OXIDES
A reflective layer for use in lighting devices and methods of forming the reflective layer are provided. The reflective layer may include a dielectric layer including one or more insulating materials. An intermediate layer may be formed on the dielectric layer. The intermediate layer may include one or more materials having a higher enthalpy of reaction than the one or more insulating materials. Because of the higher enthalpy of reaction, atoms of the one or more materials in the intermediate layer may form bonds with atoms of the one or more insulating materials. A metal layer may be formed on the intermediate layer to reflect light emitted from an active region of a light emitting diode (LED).
1 . A conductive reflective layer comprising:
a dielectric layer on an underlying layer, a dielectric layer having a first enthalpy of reaction;
an intermediate layer on the dielectric layer; and
a metal layer on the intermediate layer, the metal layer and the intermediate layer electrically coupled to the underlying layer.
2 . The conductive reflective layer of claim 1 , wherein the underlying layer is electrically conductive.
3 . The conductive reflective layer of claim 1 , wherein the dielectric layer comprises silicon oxide.
4 . The reflective layer of claim 1 , wherein the dielectric layer has a thickness ranging from 5 angstroms to 50 angstroms.
5 . The conductive reflective layer of claim 1 , wherein the intermediate layer comprises aluminum.
6 . The conductive reflective layer of claim 1 , wherein a majority of atoms of the intermediate layer form bonds with atoms of the dielectric layer.
7 . The conductive reflective layer of claim 1 , wherein the metal layer comprises a noble metal.
8 . (canceled)
9 . (canceled)
10 . The conductive layer of claim 1 , wherein the metal layer has a thickness ranging from 50 nm to 1000 nm.
11 . A method of forming a reflective layer on a light emitting diode (LED) device, the method comprising:
forming a dielectric layer under a vacuum, the dielectric layer comprising one or more insulating materials;
forming an intermediate layer on the dielectric layer under the vacuum, the intermediate layer comprising one or more materials having a higher enthalpy of reaction than the one or more insulating materials, such that atoms of the one or more materials form bonds with atoms of the one or more insulating materials; and
forming a metal layer under the vacuum on the intermediate layer.
12 . The method of claim 11 , wherein the dielectric layer is formed on an emission layer of an LED device.
13 . The method of claim 11 , wherein the dielectric layer comprises silicon oxide.
14 . The method of claim 11 , wherein the intermediate layer comprises one or more metallic materials.
15 . The method of claim 11 , wherein the intermediate layer comprises Al.
16 . The method of claim 11 , wherein the bonds formed comprise O—Al bonds.
17 . The method of claim 11 , wherein the metal layer comprises Ag.
18 . The method of claim 11 , wherein the dielectric layer and the intermediate layer are substantially transparent to light emitted from an active region of the LED device.
19 . The method of claim 11 , wherein the intermediate layer has a thickness such that a majority of atoms of the one or more materials form bonds with atoms of the one or more insulating materials.
20 . The method of claim 11 , wherein the intermediate layer has a thickness ranging from approximately 5 angstroms to approximately 20 angstroms.
21 . The conductive reflective layer of claim 1 , wherein the intermediate layer has a second enthalpy of reaction that is greater than the first enthalpy of reaction.
22 . The conductive reflective layer of claim 1 , wherein the dielectric layer is on an emission layer.
23 . A light emitting diode (LED) device comprising:
a light emitting layer; and
a conductive reflective layer comprising:
a dielectric layer on an underlying layer, the dielectric layer having a first enthalpy of reaction;
an intermediate layer on the dielectric layer; and
a metal layer on the intermediate layer, the metal layer and the intermediate layer electrically coupled to the underlying layer.