ENCAPSULATION ARRANGEMENTS IN LIGHT-EMITTING DIODE PACKAGES
Light-emitting diode (LED) packages and more particularly encapsulation arrangements in LED packages that provide reduced internal stresses are disclosed. LED packages may include housings that form a recess with one or more LED chips provided within the recess. Encapsulation arrangements include multiple encapsulation layers where a first encapsulation layer covers portions of a recess floor and sidewalls of the one or more LED chips, and a second encapsulation layer that covers the first encapsulation layer. In this manner, the first encapsulation layer is configured to buffer internal encapsulation stresses during operation that could lead to delamination of the LED chips.
1 . A light-emitting diode (LED) package comprising:
a housing that forms a recess with a recess floor and one or more recess sidewalls;
a lead frame structure extending through the housing, wherein a portion of the lead frame structure is arranged along the recess floor;
at least one LED chip arranged within the recess and electrically coupled with the lead frame structure;
a first encapsulation layer arranged on the recess floor, on the portion of the lead frame structure that is arranged along the recess floor, and on one or more sidewalls of the at least one LED chip; and
a second encapsulation layer arranged within the recess on the first encapsulation layer, wherein a weight percentage of the first encapsulation layer is less than 50% of a total encapsulation weight that is a sum of weights of the first encapsulation layer and the second encapsulation layer.
2 . The LED package of claim 1 , wherein the weight percentage of the first encapsulation layer is less than 25% of the total encapsulation weight.
3 . The LED package of claim 1 , wherein the weight percentage of the first encapsulation layer is in a range from 3% to 10% of the total encapsulation weight.
4 . The LED package of claim 1 , wherein the at least one LED chip is electrically connected to a portion of the lead frame structure with a wire bond, and a portion of the wire bond extends from the first encapsulation layer into the second encapsulation layer.
5 . The LED package of claim 1 , wherein the at least one LED chip is electrically connected to a portion of the lead frame structure with a wire bond, and a top surface of the first encapsulation layer forms an upward protrusion that is registered with the wire bond.
6 . The LED package of claim 1 , wherein the at least one LED chip comprises a plurality of LED chips and a first LED chip of the plurality of LED chips includes a top surface that resides within the second encapsulation layer.
7 . The LED package of claim 1 , wherein a top surface of the first encapsulation layer forms an upward protrusion that is registered with the at least one LED chip.
8 . The LED package of claim 1 , wherein the at least one LED chip comprises a first LED chip and a second LED chip, and a top surface of the first encapsulation layer between the first LED chip and the second LED chip is positioned at a height above the recess floor that is less than a height of the first LED chip and the second LED chip above the recess floor.
9 . The LED package of claim 1 , wherein the at least one LED chip comprises a first LED chip and a second LED chip, and the first encapsulation layer is on one or more sidewalls of the first LED chip without covering one or more sidewalls of the second LED chip.
10 . The LED package of claim 1 , wherein the first encapsulation layer and the second encapsulation layer comprise a same material.
11 . The LED package of claim 1 , wherein the first encapsulation layer covers a top surface of the at least one LED chip, and the top surface is positioned opposite the recess floor.
12 . The LED package of claim 1 , further comprising a curved lens on the second encapsulation layer.
13 . The LED package of claim 1 , wherein the second encapsulation layer forms a lens shape that is positioned above the recess.
14 . A light-emitting diode (LED) package comprising:
a housing that forms a recess with a recess floor and one or more recess sidewalls;
a lead frame structure extending through the housing, wherein a portion of the lead frame structure is arranged along the recess floor;
at least one LED chip arranged within the recess and electrically coupled with the lead frame structure;
a first encapsulation layer arranged on the recess floor, on the portion of the lead frame structure that is arranged along the recess floor, and on one or more sidewalls of the at least one LED chip, wherein the first encapsulation layer is conformal along the at least one LED chip such that a top surface of the first encapsulation layer forms an upward protrusion that is registered with the at least one LED chip; and
a second encapsulation layer arranged within the recess on the first encapsulation layer.
15 . The LED package of claim 14 , wherein the first encapsulation layer and the second encapsulation layer comprise a same material.
16 . The LED package of claim 14 , wherein the first encapsulation layer covers a top surface of the at least one LED chip, and the top surface is positioned opposite the recess floor.
17 . The LED package of claim 14 , wherein the at least one LED chip is electrically connected to a portion of the lead frame structure with a wire bond, and a portion of the wire bond extends from the first encapsulation layer into the second encapsulation layer.
18 . The LED package of claim 14 , wherein the at least one LED chip is electrically connected to a portion of the lead frame structure with a wire bond and the upward protrusion is registered with the wire bond.
19 . The LED package of claim 14 , wherein the at least one LED chip comprises a first LED chip and a second LED chip, and a top surface of the first encapsulation layer between the first LED chip and the second LED chip is positioned at a height above the recess floor that is less than a height of the first LED chip and the second LED chip above the recess floor.
20 . The LED package of claim 14 , further comprising a curved lens on the second encapsulation layer.
21 . The LED package of claim 14 , wherein the second encapsulation layer forms a lens shape that is positioned above the recess.