LED Substrate Recess Structure for Stronger Board Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Light-emitting devices face challenges in maintaining mechanical strength of the base member while enhancing bonding strength to a mounting board, as existing methods often compromise mechanical integrity for improved bonding.
Innovation Solution
The design includes a substrate with a base member featuring depressed portions on its back and bottom surfaces, where the depth of these portions is greater on the bottom surface side than on the upper surface side, allowing for increased volume of bonding material and improved bonding strength without compromising mechanical strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If depressions are formed on the mounting surfaces of supporting members to improve bonding strength, then bonding strength to mounting board is improved, but mechanical strength of base member decreases
Solution Approach 1:
The patent transitions from two-dimensional surface depressions to three-dimensional recesses with varying depths. The recesses extend deeper into the base member at certain locations, creating a stepped or tapered structure that increases bonding volume and surface area without uniformly compromising the base member's mechanical strength throughout.
Solution Approach 2:
The patent applies different depression depths at different locations within the mounting surface. Some areas have deeper recesses to enhance bonding strength where needed, while other areas maintain shallower depths to preserve mechanical strength, creating a non-uniform structure optimized for both bonding and structural integrity.
2Strength
If uniform depressions are formed across the base member, then bonding strength is improved, but mechanical strength decreases significantly
Solution Approach 1:
The patent implements non-uniform depression depths across the base member, with some regions having deeper recesses and others having shallower recesses. This localized variation allows bonding material to be concentrated where most needed for bonding strength while preserving mechanical strength in regions where deep recesses are not necessary.
Solution Approach 2:
The patent applies the depression structure partially rather than uniformly across the entire base member. By concentrating deeper recesses in specific areas where bonding enhancement is most critical, the design achieves improved bonding strength without the excessive mechanical strength loss that would result from uniform deep depressions across the entire structure.
Data Source
AI summary
A light-emitting device includes a substrate comprising a base member, a first wiring, a second wiring, and a via hole; at least one light-emitting element electrically connected to and disposed on the first wiring; and a covering member having light reflectivity and covering a lateral surface of the light-emitting element and a front surface of the substrate. The base member defines a plurality of depressed portions separated from the via hole in a front view and opening on a back surface and a bottom surface of the base member. The substrate includes a third wiring covering at least one of inner walls of the plurality of depressed portions and electrically connected to the second wiring. A depth of each of the plurality of depressed portions defined from the back surface toward the front surface is larger on a bottom surface side than on an upper surface side of the base member.