LED Package Cavity with Bottom Through Holes for Shrinkage Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Color scattering defects in light-emitting device packages occur due to non-uniform shrinking of the encapsulation material, leading to deviations in ejection amounts and form changes during the manufacturing process.
Innovation Solution
The design includes a structure with a cavity and through holes in the bottom, where the encapsulation material is filled in a gravitational direction, allowing it to shrink without altering the material's position, and the through holes are sized to maintain the material inside, preventing deformation and scattering.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the encapsulation material is ejected using a dispensing method, then the manufacturing process can be performed, but the ejection amount varies due to deviations between dispensing equipments and hardening degree, causing color scattering defects
Solution Approach 1:
The patent applies preliminary action by forming through holes in the cavity bottom before supplying the encapsulation material. This allows the material to be supplied in a gravitational direction through controlled openings, ensuring uniform ejection amount and preventing variation caused by dispensing equipment deviations. The through holes are positioned and sized in advance to control the material flow and hardening process uniformly.
2Shape
If the encapsulation material is ejected to form a flat upper surface, then the initial form is uniform, but the material shrinks during hardening causing form change to concave shape and color scattering
Solution Approach 1:
The patent applies preliminary anti-action by designing through holes in the cavity bottom that counteract the shrinking effect during hardening. The holes allow the encapsulation material to be supplied in excess in specific regions, and as the material hardens and shrinks, the gravitational supply through the holes compensates for the volume reduction, maintaining the flat upper surface form and preventing color scattering defects.
3Quantity of substance
If the encapsulation material shrinks during hardening, then the material density increases, but the non-uniform shrinking causes position change and form deformation
Solution Approach 1:
The patent uses the through holes as an intermediary mechanism between the encapsulation material supply system and the cavity. These holes control the material flow during hardening, allowing uniform gravitational supply that compensates for shrinking. The intermediary structure ensures that density increase from shrinking does not cause position changes or form deformation, maintaining manufacturing precision.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method ensures consistent encapsulation and prevents color scattering defects by compensating for material shrinkage during hardening, maintaining the encapsulation material's position and form within the package.
Implementation Method 1
the form of the encapsulation material after hardening may be changed to a concave form due to shrinking of the encapsulation material
Implementation Method 2
the encapsulation material is supplied while disposing the package main body on the fixed mold so that the encapsulation material is supplied in a gravitational direction
Data Source
AI summary
A light-emitting device package and method of manufacturing the same. The method includes: preparing a package main body comprising a plurality of cavities, wherein a light-emitting device chip is mounted in each of the cavities and a through hole is formed in a bottom of each of the cavities; preparing a fixed mold providing a first surface that blocks the cavity; coupling the package main body to the fixed mold such that an end portion of the cavity contacts the first surface; supplying an encapsulation material into the cavity through the through hole; hardening the encapsulation material; and separating the package main body from the fixed mold, and dicing the package main body into a plurality of light-emitting device packages using a singulation operation. The encapsulation material is supplied while disposing the package main body on the fixed mold so that the encapsulation material is supplied in a gravitational direction.