METHOD OF MAKING LIGHT EMITTING DEVICE AND LIGHT EMITTING DEVICE MADE THEREOF
This disclosure discloses a method of making a light-emitting device. The method comprises forming a plurality of light-emitting chips, each of the light-emitting chips comprising an epitaxial structure and an electrode formed on the epitaxial structure; forming a protection layer on the electrode in each of the light-emitting chips; forming a plurality of light-emitting groups by collecting the light-emitting chips, wherein each of the light-emitting groups having substantially the same opto-electrical characteristics; forming a wavelength converted layer in each of the light-emitting groups to cover the epitaxial structure and the protection layer; and removing the wavelength converted layer on the protection layer to expose the protection layer.
1 .- 11 . (canceled)
12 . A light-emitting device comprising:
a substrate;
a light-emitting stack formed on the substrate and having a top region;
a wavelength converted layer formed on the light-emitting stack and has a first portion covering the top region of the light-emitting stack and a second portion protruding from the first portion with a first distance.
13 . The light-emitting device of claim 12 , wherein the first distance ranges from 10 μm to 70 μm.
14 . The light-emitting device of claim 12 , wherein the second portion has a width less than that of the first portion.
15 . The light-emitting device of claim 12 , wherein each of the substrate and the light-emitting stack has a side region, and the wavelength converted layer covering and the side region of the substrate and the light-emitting stack.
16 . The light-emitting device of claim 15 , wherein the wavelength converted layer on the side region has a width smaller than a thickness of the wavelength converted layer on the top region.
17 . The light-emitting device of claim 13 , wherein the wavelength converted layer covering the top region of the light-emitting stack is spaced apart from the electrode with a second distance ranging from 1 to 10 μm.
18 . The light-emitting device of claim 13 , further comprising an electrode and a metal bump, wherein the metal bump is formed on a top surface of the electrode and has a sidewall and a top surface, and wherein the wavelength converted layer surrounds the sidewall without covering the top surface.
19 . The light-emitting device of claim 18 , further comprising a wire electrically connecting with the metal bump, and wherein the wavelength converted layer does not cover the wire.
20 . A light-emitting device comprising:
a substrate having a top surface, a bottom surface, and four side regions between the top and bottom surfaces;
a light-emitting stack on the top surface of the substrate and having a top region;
a metal bump electrically coupled to the light-emitting stack; and
a wavelength converted layer formed on the four side regions and the top region of the light-emitting stack without covering the metal bump.
21 . A method of making a light-emitting diode, comprising:
preparing a plurality of light-emitting chips, one of the plurality of light-emitting chips comprising an electrode and a protection layer covering the electrode;
forming a wavelength conversion layer on the protection layer after covering the electrode; and
exposing the electrode after forming the wavelength conversion layer.
22 . The method of claim 21 , wherein the plurality of light-emitting chips have an emission wavelength difference smaller than 10 nm.
23 . The method of claim 21 , wherein the plurality of light-emitting chips have a forward voltage difference less than 0.4V.
24 . The method of claim 21 , wherein the preparing step comprises separating a plurality of light-emitting units after the protection layer is formed on the electrode.
25 . The method of claim 24 , wherein the plurality of light-emitting units are commonly formed on a wafer.
26 . The method of claim 24 , wherein the plurality of light-emitting units comprises a first light-emitting unit formed on a first wafer, and a second light-emitting unit formed on a second wafer.
27 . The method of claim 21 , wherein the exposing step comprises partially removing the wavelength conversion layer.
28 . The method of claim 21 , wherein the exposing step comprises substantially removing the protection layer.
29 . The method of claim 21 , wherein the exposing step comprises exposing the protection layer.
30 . The method of claim 21 , further comprising a step of removing a part of the protection layer before forming the wavelength conversion layer.
31 . The method of claim 21 , wherein the electrode is surrounded by the wavelength conversion layer.
32 . The method of claim 21 , wherein the electrode has a top surface which is entirely exposed at the exposing step.
33 . The method of claim 21 , wherein the one of the plurality of light-emitting chips further comprises an epitaxial structure which is not covered by the protection layer before forming the wavelength conversion layer.
34 . A method of making a light-emitting diode, comprising:
preparing a plurality of light-emitting units which are connected with each other, one of the plurality of light-emitting units comprising an epitaxial structure and an electrode;
forming a protection layer on the electrode;
disconnecting the plurality of light-emitting units from each other; and
removing the protection layer to substantially expose the electrode.
35 . The method of claim 34 , further comprising a step of forming a wavelength conversion layer on the protection layer.
36 . The method of claim 34 , wherein the electrode has a top surface which is entirely exposed after the removing step.
37 . The method of claim 34 , wherein the removing step comprises using a solvent of N-methyl-2-pyrrolidone.
38 . The method of claim 34 , wherein the removing step is conducted after the disconnecting step.
39 . The method of claim 34 , wherein the epitaxial structure is substantially not covered by the protection layer.
40 . The method of claim 34 , further comprising a step of grouping a part of the plurality of light-emitting units into a light-emitting group before the removing step.