Light emitting device
A light emitting device includes a substrate, a plurality of micro light emitting chips and a plurality of conductive bumps. The substrate has a plurality of pads. The micro light emitting chips are disposed on the substrate in dispersion. Each of the micro light emitting chips includes an N-type semiconductor layer, an active layer and a P-type semiconductor layer. The conductive bumps are disposed corresponding to the micro light emitting chips and located between the micro light emitting chips and the substrate. The micro light emitting chips are electrically connected to the pads of the substrate by the conductive bumps. The orthogonal projection area of each of the conductive bumps on the substrate is 1.05 times to 1.5 times of the orthogonal projection area of each of the micro light emitting chips on the substrate.
1. A light emitting device, comprising:
a substrate, having a plurality of pads;
a plurality of micro light emitting chips, disposed on the pads of the substrate in dispersion, each of the micro light emitting chips comprises an N-type semiconductor layer, an active layer and a P-type semiconductor layer; and
a plurality of conductive bumps, disposed corresponding to the micro light emitting chips and located between the micro light emitting chips and the substrate, and the micro light emitting chips are electrically connected to the pads of the substrate by the conductive bumps, wherein an orthogonal projection area of each of the conductive bumps on the substrate is 1.05 times to 1.5 times of an orthogonal projection area of each of the micro light emitting chips on the substrate, wherein a width of each of the conductive bumps is respectively larger than a width of each of the micro light emitting chips and a width of each of the pads of the substrate.
2. The light emitting device as claimed in claim 1 , wherein each of the micro light emitting chips further includes a first electrode structurally and electrically connected to one of the conductive bumps, and a thickness of each of the conductive bumps is greater than a thickness of each of the first electrodes.
3. The light emitting device as claimed in claim 1 , wherein the active layers of the micro light emitting chips have similar height levels, and the N-type semiconductor layers of the micro light emitting chips have different thicknesses.
4. The light emitting device as claimed in claim 1 , wherein the conductive bumps have different thicknesses.
5. The light emitting device as claimed in claim 1 , wherein each of the conductive bumps comprises at least one gold layer and at least one alloy layer located on the gold layer, each of the pads at least comprises a copper layer and an indium layer located on the copper layer, and the gold layer of each of the conductive bumps directly contacts the indium layer of each of the pads.
6. A light emitting device, comprising:
a substrate, having a plurality of pads;
a plurality of micro light emitting chips, disposed on the pads of the substrate in dispersion, each of the micro light emitting chips comprises an N-type semiconductor layer, an active layer and a P-type semiconductor layer; and
a plurality of conductive bumps, disposed corresponding to the micro light emitting chips and located between the micro light emitting chips and the substrate, and the micro light emitting chips are electrically connected to the pads of the substrate by the conductive bumps, wherein an orthogonal projection area of each of the conductive bumps on the substrate is greater than an orthogonal projection area of each of the micro light emitting chips on the substrate, wherein a width of each of the conductive bumps is larger than a width of each of the micro light emitting chips, wherein a thickness of each of the conductive bumps is greater than a thickness of each of the micro light emitting chips.
7. The light emitting device as claimed in claim 6 , wherein the active layers of the micro light emitting chips have similar height levels, and the N-type semiconductor layers of the micro light emitting chips have different thicknesses.
8. The light emitting device as claimed in claim 6 , wherein the conductive bumps have different thicknesses.
9. The light emitting device as claimed in claim 6 , wherein a thickness of each of the conductive bumps is greater than a thickness of each of the pads.
10. The light emitting device as claimed in claim 6 , wherein each of the conductive bumps comprises at least one gold layer and at least one alloy layer located on the gold layer, each of the pads at least comprises a copper layer and an indium layer located on the copper layer, and the gold layer of each of the conductive bumps directly contacts the indium layer of each of the pads.
11. A light emitting device, comprising:
a substrate, having a plurality of pads;
a plurality of micro light emitting chips, disposed on the pads of the substrate in dispersion, each of the micro light emitting chips comprises a first electrode, an N-type semiconductor layer, an active layer and a P-type semiconductor layer; and
a plurality of conductive bumps, disposed corresponding to the micro light emitting chips in a one-to-one manner and located between the micro light emitting chips and the substrate, and the micro light emitting chips are electrically connected to the pads of the substrate by the conductive bumps, wherein the first electrode of each of the micro light emitting chips is structurally and electrically connected to one of conductive bumps, an orthogonal projection area of each of the conductive bumps on the substrate is respectively greater than an orthogonal projection area of the N-type semiconductor layer, an orthogonal projection area of the active layer and an orthogonal projection area of the P-type semiconductor layer on the substrate, wherein a width of each of the conductive bumps is respectively larger than a width of the N-type semiconductor layer, a width of the active layer and a width of the P-type semiconductor layer, wherein a thickness of each of the conductive bumps is greater than a sum of a thickness of the N-type semiconductor layer, a thickness of the active layer and a thickness of the P-type semiconductor layer.
12. The light emitting device as claimed in claim 11 , wherein a thickness of each of the conductive bumps is larger than a thickness of the first electrode.
13. The light emitting device as claimed in claim 11 , wherein a width of each of the conductive bumps is larger than a width of each of the micro light emitting chips.
14. The light emitting device as claimed in claim 11 , wherein the active layers of the micro light emitting chips have similar height levels, and the N-type semiconductor layers of the micro light emitting chips have different thicknesses.
15. The light emitting device as claimed in claim 11 , wherein the conductive bumps have different thicknesses.
16. The light emitting device as claimed in claim 11 , wherein a thickness of each of the conductive bumps is greater than a thickness of each of the pads.
17. The light emitting device as claimed in claim 11 , wherein an orthogonal projection area of each of the conductive bumps on the substrate is greater than an orthogonal projection area of each of the micro light emitting chips.
18. The light emitting device as claimed in claim 11 , wherein each of the conductive bumps comprises at least one gold layer and at least one alloy layer located on the gold layer, each of the pads at least comprises a copper layer and an indium layer located on the copper layer, and the gold layer of each of the conductive bumps directly contacts the indium layer of each of the pads.