Light emitting diode device with reconstituted LED components on substrate
Disclosed herein are technologies for forming a plurality of known good die (KGD)-light emitting diode (LED) components into a larger size optically coherent LED chips or devices. This Abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
1. A method of joining multiple light emitting diode (LED) components, the method comprising:
testing a wafer for a known good die (KGD)-LED component;
flip chip bonding multiple KGD-LED components onto a substrate, the substrate includes redistribution layers (RDLs) that facilitate electrical connections between the KGD-LED components and an operating device; and
under-filling a gap and spaces in between the KGD-LED components with a transparent material, wherein the transparent material is transparent to a light wavelength emitted by the LED components and has a refractive index close to a refractive index of the substrate that is transparent.
2. The method of claim 1 , wherein the KGD-LED component includes a thinned sapphire substrate, which has a rough upper surface and a patterned lower surface.
3. The method of claim 2 , wherein the rough upper surface is approximately 0.3 to 3 micrometers in roughness.
4. The method of claim 1 , wherein the electrical connections facilitated by the RDLs include series or parallel connections.
5. The method of claim 1 , wherein the gap dimension between the KGD-LED components, or shape of the KGD or pattern of the KGD or combination thereof are configured to facilitate free flowing of the transparent under-filling material.
6. The method of claim 1 , wherein the gap is equal to or less than 100 micrometers.
7. The method of claim 1 , wherein the transparent material has a roughened surface that is formed after curing of the under-filling.
8. A plurality of joined known good die (KGD)-light emitting diode (LED) components comprising:
a stack of LED layers that include a transparent substrate with a roughened upper surface and a patterned lower surface;
a reflective electrode coupled to the stack of LED layers, wherein the reflective electrode includes a diffusive reflection at one side and a rough interface to the stack of LED layers at an other side;
a probe pad that is connected to the reflective electrode, wherein the stack of LED layers, the reflective electrode and the probe pad form a single KGD-LED component; and
a mounting substrate with a redistribution layer (RDL) that connects multiple probe pads of multiple KGD-LED components to an operating device, wherein a transparent under-filling material is formed in a gap and spaces in between the KGD-LED components that are mounted unto the mounting substrate, wherein the transparent material is transparent to a light wavelength emitted by the LED components.
9. The plurality of joined KGD-LED components of claim 8 , wherein the RDL facilitates series or parallel connection between the KGD-LED components and the operating device.
10. The plurality of joined KGD-LED components of claim 8 , wherein the stack of LED layers include a thinned sapphire substrate.
11. The plurality of joined KGD-LED components of claim 8 , wherein the gap dimension between the KGD-LED components, or shape of the KGD, or pattern of the KGD, or combination thereof are configured to facilitate free flowing of the transparent under-filling material.
12. The plurality of joined KGD-LED components of claim 8 , wherein the gap is equal to or less than 100 micrometers.
13. The plurality of joined KGD-LED components of claim 8 further comprising a dielectric that at least partially surround the stack of LED layers.
14. The plurality of joined KGD-LED components of claim 8 , wherein the transparent under-filling material has a refractive index close to a refractive index of the transparent substrate.
15. A device comprising:
a power source; and
a plurality of joined known good die (KGD)-light emitting diode (LED) components that further comprises:
a stack of LED layers that include a transparent substrate with a roughened upper surface and a patterned lower surface;
a reflective electrode coupled to the stack of LED layers, wherein the reflective electrode includes a diffusive reflection at one side and a rough interface to the stack of LED layers at another side;
a probe pad that is connected to the reflective electrode, wherein the stack of LED layers, the reflective electrode and the probe pad form one KGD-LED component; and
a mounting substrate with a redistributive layer (RDL) that connects multiple probe pads of the plurality of KGD-LED components to the power source, wherein a transparent under-filling material is formed in a gap and spaces in between the KGD-LED components, the transparent under-filling material has a refractive index close to a refractive index of the transparent substrate and is transparent to a light wavelength emitted by the LED components.
16. The device of claim 15 , wherein the RDL facilitates series or in parallel connection between the KGD-LED components and the power source.
17. The device of claim 15 , wherein the stack of LED layers include a thinned sapphire substrate.