Light emitting diode device and manufacturing method thereof
A light emitting diode device includes a light emitting diode chip, a wavelength conversion layer including a bottom surface facing a top surface of the light emitting diode chip, and an interlayer having a first portion between the light emitting diode chip and a part of the bottom surface of the wavelength conversion layer, and a second portion extending from the first portion and connected between a remaining part of the bottom surface of the wavelength conversion layer and a side surface of the light emitting diode chip. The second portion has a side surface including a linear surface substantially aligning with a side surface of the wavelength conversion layer, and a curved surface having a first end connected to the linear surface and a second end connected to the side surface of the light emitting diode chip. The linear surface and the curved surface define a chamfer angle.
1. A method of manufacturing a light emitting diode device, comprising:
providing a wavelength conversion layer;
forming an interlayer on the wavelength conversion layer, wherein the interlayer is adhesive;
disposing a plurality of light emitting diode chips on the interlayer at intervals;
heating and pressing the interlayer such that a portion of the interlayer flows to the intervals between the light emitting diode chips and side surfaces of the light emitting diode chips, wherein a surface of the interlayer on the intervals between the light emitting diode chips forms a curved surface, the heating and the pressing make a tan δ of the interlayer be in a range from about 0.7 to about 3.0, and the tan δ equals to G″/G′, in which G′ is a storage elastic modulus of the interlayer, and G″ is a loss elastic modulus of the interlayer;
making a first cut through the interlayer on the intervals between the light emitting diode chips and the underlying wavelength conversion layer to form a plurality of light emitting units, wherein the first cut allows the interlayer to have at least one side surface, the side surface and the curved surface after making the first cut form a chamfer angle; and
forming a reflective element to wrap a side surface of each of the light emitting units.
2. The method of claim 1 , further comprising performing a solidification process, wherein the solidification process is performed after the heating and the pressing such that the interlayer is solidified on the side surface of the light emitting diode chips.
3. The method of claim 1 , wherein the chamfer angle is in a range from about 90° to about 160°.
4. The method of claim 1 , wherein after making the first cut, a substrate is provided such that the light emitting units are disposed on the substrate, and the reflective element is formed on the substrate to wrap side surfaces of each of the light emitting units.
5. The method of claim 4 , further comprising making a second cut through the reflective element between the light emitting units to form the light emitting units wrapped by the reflective element.
6. The method of claim 5 , wherein the substrate is removed after making the second cut.
7. The method of claim 4 , wherein after providing the substrate, the light emitting units are upside down to allow the light emitting diode chips to be in contact with the substrate.
8. The method of claim 7 , further comprising making a second cut through the reflective element and the substrate between the light emitting units to form the light emitting units wrapped by the reflective element on the substrate.
9. The method of claim 8 , wherein the substrate is a wiring substrate, and the light emitting diode chip is flip chip mounted to the wiring substrate.