Light emitter with a voltage dependent resistor layer
View Patent ↗A light emitter includes an emitting stack, a first electrode, a second electrode and a voltage dependent resistor layer. The emitter stack has a first surface area and a second surface area. The first electrode is formed on the first surface area of the emitting stack. The second electrode is formed on the second surface area of the emitting stack. The voltage dependent resistor layer is connected to the first and second electrodes, and is formed during the formation of the light emitter thus improving the yield of the light emitter.
1. A light emitter comprising:
an emitting stack having a first surface area and a second surface area;
a first electrode formed on the first surface area of the emitting stack;
a second electrode formed on the second surface area of the emitting stack; and
a voltage dependent resistor layer formed on the emitting stack and connected to the first and second electrodes.
2. The light emitter of claim 1 wherein the first and second surface areas are on the same side of the emitting stack.
3. The light emitter of claim 1 wherein the first and second surface areas are on different sides of the emitting stack.
4. The light emitter of claim 1 further comprising a substrate,
wherein the emitting stack comprises: a first contad layer formed on the substrate; a first cladding layer formed on a first surface area of the first contact layer; an emitting layer formed on the first cladding layer; a second cladding layer formed on the emitting layer; and a second contact layer formed on the second cladding layer;
wherein the first electrode is formed on a second surface area of the first contact layer, and the second electrode is formed on the second contact layer.
5. The light emitter of claim 4 wherein the substrate comprises at least one material selected from a group consisting of Si, GaAs, SiC, GaP, AlGaAs, GaAsP, Al2O3, and glass materials.
6. The light emitter of claim 4 wherein each of the contact layers comprises at least one material selected from a group consisting of GaP, GaAs, GaAsP, InGaP, AlGaInP, AlGaAs, GaN, InGaN, AlGaN, and AlGaInN.
7. The light emitter of claim 4 wherein each of the cladding layers comprises at least one material selected from a group consisting of AlGaInP, AlN, GaN, AlGaN, InGaN, and AlGaInN.
8. The light emitter of claim 4 wherein the emitting layer comprises at least one material selected from a group consisting of AlGaInP, GaN, InGaN, and AlGaInN.
9. The light emitter of claim 4 further comprising a first transparent oxide conductive layer formed between the first electrode and the second surface area of the first contact layer, and a second transparent oxide conductive layer formed between the second electrode and the second contact layer, each of the transparent oxide conductive layers comprising at least one material selected from a group consisting of indium tin oxide, cadmium tin oxide, antimony tin oxide, zincoxide, and zinc tin oxide.
10. The light emitter of claim 1 wherein the voltage dependent resistor layer comprises at least one material selected from a group consisting of ZnO, CaF 2 , ZnS, TiO 2 , Al—Al 2 O 3 —Au, Co—NiO, polymethyl-methylacrylate, and SrTiO 3 .
11. The light emitter of claim 4 wherein the voltage dependent resistor layer is formed on the second contact layer and on a side of the emitting stack for respectively connecting to the second electrode and the first electrode.
12. The light emitter of claim 11 wherein the voltage dependent resistor layer is formed on the second contact layer beside the second electrode for connecting to the second electrode.
13. The light emitter of claim 1 wherein the voltage dependent resistor layer is formed directly on the emitting stack.