Packaged semiconductor light emitting devices having multiple optical elements
View Patent ↗Methods of packaging a semiconductor light emitting device include providing a substrate having the semiconductor light emitting device on a front face thereof. A first optical element is formed from a first material on the front face proximate the semiconductor light emitting device but not covering the semiconductor light emitting device and a second optical element is formed from a second material, different from the first material, over the semiconductor light emitting device and the first optical element. Packaged semiconductor light emitting devices are also provided.
1. A packaged semiconductor light emitting device, comprising:
a substrate;
a semiconductor light emitting device on a front face of the substrate;
a first optical element on the front face of the substrate proximate the semiconductor light emitting device but not covering the semiconductor light emitting device, wherein the first optical element comprises a ring around the semiconductor light emitting device having a curved top and wherein the ring comprises a toroidal shape; and
a second optical element on the front face of the substrate over the semiconductor light emitting device and the first optical element, wherein the first and second optical elements comprise different materials to provide the first optical element and the second optical element different refractive indexes selected to provide a desired optical characteristic for the packaged semiconductor light emitting device.
2. The device of claim 1 , wherein the semiconductor light emitting device is flush on the front face of the substrate without a reflector cavity and wherein the second optical element extends from the front face of the substrate in a region surrounding the semiconductor light emitting device and extends over the semiconductor light emitting device.
3. The device of claim 1 , further comprising a wire bond that electrically couples the semiconductor light emitting device to a contact portion the substrate and wherein the second optical element is a compression molded optical element that directly contacts the wire bond.
4. The device of claim 3 , wherein the second optical element comprises a first material having an adhesion characteristic selected to facilitate adhesion of the first optical element to the substrate during compression molding and to limit stress applied to the light emitting device and/or a wire bond coupled thereto during thermal cycling of the packaged semiconductor light emitting device.
5. The device of claim 1 , wherein the desired optical characteristic comprises a selected viewing angle of the packaged semiconductor light emitting device.
6. The device of claim 1 , wherein the first optical element extends entirely around the light emitting device.
7. The device of claim 1 , wherein the first optical element comprises an additive.
8. The device of claim 1 , wherein the second optical element comprises an additive.
9. The device of claim 1 , wherein the first optical element comprises a first additive and the second optical element comprises a second additive different form the first additive.
10. The device of claim 1 , wherein the first optical element comprises an additive such that the first optical element provides greater efficiency in light extraction from the semiconductor light emitting device than a reflective cavity.
11. The device of claim 1 , wherein the ring is symmetrical along a vertical axis orthogonal to a radius of the ring at any point on the ring.
12. A packaged semiconductor light emitting device, comprising:
a substrate;
a semiconductor light emitting device on a front face of the substrate;
a first optical element on the front face of the substrate proximate the semiconductor light emitting device but not covering the semiconductor light emitting device, wherein the first optical element comprises a ring around the semiconductor light emitting device having a curved top; and
a second optical element on the front face of the substrate over the semiconductor light emitting device and the first optical element, wherein the second optical element directly contacts the semiconductor light emitting device, wherein the second optical element directly contacts an entire external surface of the first optical element that is not contacting the front face of the substrate and wherein the optical elements comprise a material different from a material of the substrate, and wherein at least one of the first and second optical elements comprises an additive to affect optical properties.
13. The device of claim 12 , wherein the first optical element extends entirely around the light emitting device.