Power surface mount light emitting die package

• US 7,976,186 B2
• Filed: 08/13/2010
• Issued: 07/12/2011
• Est. Priority Date: 05/27/2003
• Status: Expired due to Term

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Loh, Ban P.
• Primary Examiner(s): Alavi; Ali
• Application Number:
  US12/856,320
• Publication Number:
  US 20100301372A1
• Time in Patent Office: 333 Days
• Field of Search: 362/294, 362/245, 362/246, 257 98-100
• US Class Current: 362/245
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/641 characterized by the materials
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A light emitting die package includes a substrate, a reflector plate, and a lens. The substrate has traces for connecting an external electrical power source to a light emitting diode (LED) at a mounting pad. The reflector plate is coupled to the substrate and substantially surrounds the mounting pad, and includes a reflective surface to direct light from the LED in a desired direction. The lens is free to move relative to the reflector plate and is capable of being raised or lowered by the encapsulant that wets and adheres to it and is placed at an optimal distance from the LED chip(s). Heat generated by the LED during operation is drawn away from the LED by both the substrate (acting as a bottom heat sink) and the reflector plate (acting as a top heat sink).

Claims

1. A semiconductor die package, comprising:

a substrate,

a light emitting diode (LED) mounted on the substrate via a mounting pad so that the LED is electrically connected to a top surface of the substrate,

a reflector plate coupled to the substrate and substantially surrounding the mounting pad and LED, the reflector plate having an opening there through,

a lens placed in the opening to substantially cover the mounting pad, LED and opening, and

an encapsulant covering the LED within at least part of the opening, wherein the lens adheres to the encapsulant so that the lens floats on the encapsulant within the opening.

2. The semiconductor die package of claim 1, wherein the reflector plate further defines a reflection surface.

3. The semiconductor die package of claim 1, wherein the reflector plate and substrate serve as corresponding top and bottom heat sinks for removing heat away from the LED during package operation.

4. An apparatus comprising:

a substrate having a top surface and a bottom surface, a portion of the top surface defining a mounting pad;

a plurality of conductive traces on the top surface of said substrate, said conductive traces extending from the mounting pad to a side edge of said substrate and said conductive traces comprising electrically conductive material;

a reflector attached to the top surface of said substrate, said reflector surrounding the mounting pad while leaving other portions of the top surface of said substrate and portions of the conductive traces exposed, said reflector partially defining an optical cavity;

at least one photonic device attached to at least one conductive trace at the mounting pad; and

a heat sink coupled to the bottom surface of said substrate.