Ultraviolet emitting device with shaped encapsulant

• US 10,062,817 B1
• Filed: 01/10/2017
• Issued: 08/28/2018
• Est. Priority Date: 01/10/2017
• Status: Active Grant

• Current Assignee: Rayvio Corporation
• Original Assignee: Rayvio Corporation
• Inventors: Sudradjat, Faisal, Liu, Saijin, Collins, Douglas A.
• Primary Examiner(s): Bachner, Robert
• Assistant Examiner(s): Reida, Molly
• Application Number:
  US15/402,621
• Time in Patent Office: 595 Days
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/52 Encapsulations
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

Embodiments of the invention include a light emitting diode (UVLED), the UVLED including a semiconductor structure with an active layer disposed between an n-type region and a p-type region. The active layer emits UV radiation. The UVLED is disposed on a mount. A transparent encapsulant is disposed over the UVLED. The transparent encapsulant has an angled sidewall.

Claims

1. A device comprising:

a light emitting diode (UVLED) comprising a semiconductor structure comprising an active layer disposed between an n-type region and a p-type region, wherein the active layer emits UV radiation;

a mount, wherein the UVLED is disposed on the mount; and

a transparent encapsulant disposed over the UVLED, the transparent encapsulant having an angled sidewall, wherein the angled sidewall is freestanding and not in contact with any structure, and wherein the angled sidewall is no more than 1 mm from an edge of the UVLED.

2. The device of claim 1 further comprising a feature formed on a top surface of the encapsulant.

3. The device of claim 2 wherein the feature is a trench disposed between the UVLED and the angled sidewall.

4. The device of claim 2 wherein the feature is a trench with angled sidewalls.

5. The device of claim 2 wherein the feature is a trench that surrounds the UVLED.

6. The device of claim 2 wherein the feature is a trench between 40% and 60% of a thickness of the encapsulant.

7. The device of claim 2 wherein the feature comprises a plurality of holes.

8. The device of claim 2 wherein the feature is formed in a first region of the top surface, wherein a second region of the top surface does not include a feature.

9. The device of claim 2 wherein the feature comprises roughening.

10. The device of claim 1 further comprising a reflector cup formed on a top surface of the mount, wherein the UVLED is disposed within the reflector cup.

11. The device of claim 1 wherein an index of refraction varies across a thickness of the encapsulant.

12. The device of claim 11 wherein the encapsulant comprises a transparent material mixed with one of bubbles and beads.

13. The device of claim 1 further comprising an electrostatic discharge protection chip disposed outside the encapsulant.

14. The device of claim 1 wherein angled sidewall is corrugated.