Semiconductor light emitting device substrate strips and packaged semiconductor light emitting devices
View Patent ↗Semiconductor light emitting device packaging methods include fabricating a substrate configured to mount a semiconductor light emitting device thereon. The substrate may include a cavity configured to mount the semiconductor light emitting device therein. The semiconductor light emitting device is mounted on the substrate and electrically connected to a contact portion of the substrate. The substrate is liquid injection molded to form an optical element bonded to the substrate over the semiconductor light emitting device. Liquid injection molding may be preceded by applying a soft resin on the electrically connected semiconductor light emitting device in the cavity. Semiconductor light emitting device substrate strips are also provided.
1. A packaged semiconductor light emitting device comprising:
a substrate member including a metal base structure having a mounting portion;
a semiconductor light emitting device mounted on the mounting portion; and
an optical element disposed over the semiconductor light emitting device and bonded directly to the metal base structure;
wherein:
the semiconductor light emitting device is mounted on a substantially planar mounting surface of the mounting portion; and
the optical element is directly bonded to a contact surface of the metal base structure that is substantially coplanar with the mounting surface.
2. The packaged semiconductor light emitting device of claim 1 wherein the metal base structure is a lead frame.
3. The packaged semiconductor light emitting device of claim 1 wherein the substrate member includes the metal base structure overmolded with a substrate formed of a plastic material.
4. The packaged semiconductor light emitting device of claim 3 wherein the plastic material is a high temperature plastic material that is a harder material than a material of the optical element and has a lower optical transmissivity than the material of the optical element.
5. The packaged semiconductor light emitting device of claim 4 wherein the high temperature plastic material includes a reflective material additive.
6. The packaged semiconductor light emitting device of claim 4 wherein the high temperature plastic material comprises a polyphthalamide (PPA) and/or a liquid crystal polymer (LCP) and wherein the optical element comprises a thermoset resin.
7. The packaged semiconductor light emitting device of claim 3 wherein:
a receiving cavity is defined in the substrate; and
the semiconductor light emitting device is electrically connected to a lead defined by the metal base structure that extends through the substrate to the receiving cavity.
8. The packaged semiconductor light emitting device of claim 7 wherein the metal base structure is a lead frame.
9. The packaged semiconductor light emitting device of claim 1 wherein the optical element bonded to the substrate member is liquid injection molded to the substrate member over the semiconductor light emitting device.
10. The packaged semiconductor light emitting device of claim 9 wherein the optical element bonded to the substrate member is liquid injection molded directly onto the substrate member over the semiconductor light emitting device.
11. The packaged semiconductor light emitting device of claim 1 wherein the substrate member includes a receiving cavity within which the semiconductor light emitting device is mounted, and including a soft resin on the electrically connected semiconductor light emitting device in the cavity.
12. The packaged semiconductor light emitting device of claim 11 wherein the semiconductor light emitting device is electrically connected to a contact portion of the metal base structure by a bond wire, and the soft resin is disposed between the optical element and the semiconductor light emitting device.
13. The packaged semiconductor light emitting device of claim 12 wherein the optical element comprises a higher durometer material than the soft resin, has a refractive index substantially similar to a refractive index of the soft resin to limit total internal reflection of the semiconductor light emitting device, and has a coefficient of thermal expansion substantially similar to a coefficient of thermal expansion of the soft resin.
14. The substrate strip of claim 11 , wherein the soft resin comprises silicone.
15. The packaged semiconductor light emitting device of claim 1 wherein the optical element has a dome-shaped outer surface.
16. A packaged semiconductor light emitting device comprising:
a substrate member including a metal base structure having a mounting portion;
a semiconductor light emitting device mounted on the mounting portion; and
an optical element disposed over the semiconductor light emitting device and bonded directly to the metal base structure;
wherein the substrate member includes the metal base structure overmolded with a substrate formed of a plastic material.
17. The packaged semiconductor light emitting device of claim 16 wherein the plastic material is a high temperature plastic material that is a harder material than a material of the optical element and has a lower optical transmissivity than the material of the optical element.
18. The packaged semiconductor light emitting device of claim 17 wherein the high temperature plastic material includes a reflective material additive.
19. The packaged semiconductor light emitting device of claim 17 wherein the high temperature plastic material comprises a polyphthalamide (PPA) and/or a liquid crystal polymer (LCP) and wherein the optical element comprises a thermoset resin.
20. The packaged semiconductor light emitting device of claim 16 wherein:
a receiving cavity is defined in the substrate; and
the semiconductor light emitting device is electrically connected to a lead defined by the metal base structure that extends through the substrate to the receiving cavity.
21. The packaged semiconductor light emitting device of claim 20 wherein the metal base structure is a lead frame.
22. The packaged semiconductor light emitting device of claim 16 wherein the optical element has a dome-shaped outer surface.
23. A packaged semiconductor light emitting device comprising:
a substrate member including a mounting portion having a substantially planar mounting surface;
a semiconductor light emitting device mounted on the mounting surface; and
an optical element disposed over the semiconductor light emitting device and bonded directly to a contact surface of the substrate member that is substantially coplanar with the mounting surface;
wherein the substrate member includes a metal base structure; and
wherein the substrate member includes the metal base structure overmolded with a substrate formed of a plastic material.
24. The packaged semiconductor light emitting device of claim 23 wherein the optical element has a dome-shaped outer surface.