Light emitting device package with reflective side coating
A light-emitting device is disclosed that includes a semiconductor structure having an active region disposed between an n-type layer and a p-type layer; a wavelength converter formed above the semiconductor structure; an insulating side coating formed around the semiconductor structure; and a reflective side coating formed around the wavelength converter above the insulating side coating, the reflective side coating having a top surface that is flush with a top surface of the wavelength converter.
1. A light-emitting device, comprising:
a substrate;
a semiconductor structure disposed on the substrate, the semiconductor structure having an active region disposed between an n-type layer and a p-type layer;
a wavelength converter formed above the substrate;
an insulating side coating formed around the semiconductor structure; and
a reflective side coating formed around the wavelength converter and the substrate, the reflective side coating being stacked over the insulating side coating, the reflective side coating having a top surface that is flush with a top surface of the wavelength converter, and the reflective side coating having a bottom surface that is disposed above a top surface of the insulating side coating.
2. The light-emitting device of claim 1 , wherein the reflective side coating is arranged to lead heat generated by the wavelength converter away from the wavelength converter.
3. The light-emitting device of claim 1 , wherein the reflective side coating has a thermal conductivity of at least 200 W/mK.
4. The light-emitting device of claim 1 , wherein:
the insulating side coating includes a first binder material filled with reflective particles, and
the reflective side coating includes a second binder material filled with a metal powder.
5. The light-emitting device of claim 1 , wherein:
the wavelength converter includes a plurality of sidewalls,
the wavelength converter is wider than the substrate, such that a portion of a bottom surface of the wavelength converter overhangs the substrate, and
the reflective side coating is thermally coupled with the plurality of sidewalls of the wavelength converter and the portion of the bottom surface of the wavelength converter that overhangs the substrate.
6. The light-emitting device of claim 1 , wherein the insulating side coating is arranged to insulate the semiconductor structure from the reflective side coating.
7. The light-emitting device of claim 1 , wherein the reflective side coating includes silver.
8. A light-emitting device, comprising:
a light-emitting diode (LED) die including a semiconductor structure and a wavelength converter formed above the semiconductor structure;
an insulating side coating formed around the LED die, the insulating side coating including a first binder material filled with reflective particles; and
a reflective side coating formed around the LED die, the reflective side coating being stacked over the insulating side coating, the reflective side coating including a second binder material filled with metal powder, the reflective side coating being thermally coupled to the wavelength converter, the reflective side coating having a top surface that is flush with a top surface of the wavelength converter, and the reflective side coating having a bottom surface that is disposed over a top surface of the insulating side coating.
9. The light-emitting device of claim 8 , wherein the reflective side coating includes a silver material, a binder, and at least one additive that is arranged to promote adhesion between the wavelength converter and the reflective side coating.
10. The light-emitting device of claim 8 , wherein the insulating side coating is arranged to surround the semiconductor structure and substantially cover one or more sides of the semiconductor structure.
11. The light-emitting device of claim 8 , wherein the insulating side coating is arranged to insulate the semiconductor structure from the reflective side coating.
12. The light-emitting device of claim 8 , wherein the reflective side coating is arranged to surround the wavelength converter and substantially cover one or more sides of the wavelength converter.
13. The light-emitting device of claim 8 , wherein the reflective side coating is arranged to lead heat generated by the wavelength converter away from the wavelength converter.
14. The light-emitting device of claim 8 , further comprising a substrate disposed between the wavelength converter and the semiconductor structure, wherein:
the wavelength converter includes a plurality of sidewalls,
the wavelength converter is wider than the substrate, such that a portion of a bottom surface of the wavelength converter overhangs the substrate, and
the reflective side coating is thermally coupled with the plurality of sidewalls of the wavelength converter and the portion of the bottom surface of the wavelength converter that overhangs the substrate.
15. A method for manufacturing a light-emitting device, comprising:
placing a light emitting diode (LED) die on a support, the LED die including:
a semiconductor structure having an active region disposed between an n-type layer and a p-type layer; and
a wavelength converter formed above the semiconductor structure;
forming an insulating side coating around the semiconductor structure; and
forming a reflective side coating around the wavelength converter by stacking the reflective side coating over the insulating side coating, the reflective side coating having a top surface that is flush with a top surface of the wavelength converter, and the reflective side coating having a bottom surface that is disposed over a top surface of the insulating side coating.
16. The method of claim 15 , wherein forming the insulating side coating comprises:
placing a stencil on the LED die, the stencil defining a trench around the LED die;
applying an insulating material into the trench; and
causing the insulating material to spread towards one or more sidewalls of the semiconductor structure by removing the stencil.
17. The method of claim 16 , wherein the trench is deeper than a height of the semiconductor structure, and the insulating material is applied in sufficient amounts to substantially cover one or more sidewalls of the semiconductor structure when the stencil is removed.
18. The method of claim 15 , wherein forming the reflective side coating comprises:
placing a stencil on the LED die, the stencil defining a trench around the LED die;
applying a reflective material into the trench; and
removing the stencil to allow the reflective material to spread towards one or more sidewalls of the wavelength converter.
19. The method of claim 18 , wherein the reflective material is applied in sufficient amounts to substantially cover one or more sidewalls of the wavelength converter when the stencil is removed without overflowing onto the top surface of the wavelength converter.
20. The method of claim 15 , wherein:
a substrate is disposed over the semiconductor structure,
the wavelength converter is disposed over the substrate,
the wavelength converter is wider than the substrate, such that a portion of a bottom surface of the wavelength converter overhangs the substrate, and
the reflective side coating is thermally coupled with a plurality of sidewalls of the wavelength converter and the portion of the bottom surface of the wavelength converter that overhangs the substrate.