Light Emitting Device Heat Dissipation Terminal Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Compact light emitting devices face challenges with heat dissipation and mounting stability, particularly in side-mount configurations, where accurate positioning and heat management are critical for effective operation.

Innovation Solution

A light emitting device design featuring a substrate with an insulating base material, connection terminals, a heat dissipation terminal exposed between the connection terminals, and a light blocking sealing member that forms the same plane as the substrate, enhancing heat dissipation and mounting accuracy through a solder resist that controls solder placement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If a compact light emitting device is used, then the device size is reduced, but heat dissipation performance deteriorates

Engineering Contradiction:
Improvedevice sizeVSAvoidheat dissipation performance
Core Design Contradiction:
Volume of moving objectVSTemperature

Solution Approach 1:

The patent extends the heat dissipation structure from a two-dimensional surface pattern to a three-dimensional protruding terminal structure. The heat dissipation terminal protrudes from the rear surface of the substrate, creating a vertical dimension for heat dissipation that does not increase the overall device footprint, thus resolving the contradiction between compact size and heat dissipation performance

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent separates the heat dissipation function from the connection function by providing distinct terminals: connection terminals for electrical connection and a dedicated heat dissipation terminal for thermal management. This segmentation allows each terminal to be optimized for its specific function without compromising the other, enabling compact design while maintaining effective heat dissipation

Inventive Principle:
Principle #1Segmentation

2Volume of moving object

If a compact light emitting device is used, then the device size is reduced, but mounting stability deteriorates

Engineering Contradiction:
Improvedevice sizeVSAvoidmounting stability
Core Design Contradiction:
Volume of moving objectVSStability of the object's composition

Solution Approach 1:

The patent utilizes the vertical dimension by providing protruding terminals that extend beyond the substrate surface. These protruding terminals engage with corresponding mounting holes in the circuit board, creating mechanical interlocking that enhances mounting stability without increasing the device's planar footprint

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent incorporates a solder resist pattern that defines precise mounting areas on the substrate surface. This preliminary preparation of the mounting interface ensures accurate positioning and reliable solder joint formation during the mounting process, thereby maintaining mounting stability in compact devices

Inventive Principle:
Principle #10Preliminary action

3Manufacturing precision

If solder resist is used to define heat dissipation terminal, then manufacturing precision is improved, but device complexity increases

Engineering Contradiction:
Improvemounting position accuracyVSAvoidstructure complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The solder resist layer serves multiple functions: it provides electrical insulation, defines the precise boundaries of the heat dissipation terminal, and creates mounting reference areas. By combining these functions into a single layer, the patent achieves high manufacturing precision without proportionally increasing device complexity

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent integrates the heat dissipation terminal definition directly into the solder resist pattern rather than requiring separate masking or etching steps. This merging of the terminal definition process with the existing solder resist application process simplifies manufacturing while maintaining precise terminal positioning

Inventive Principle:
Principle #5Merging (Combining)

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

The design achieves improved heat dissipation and mounting stability, ensuring reliable operation and increased production yield by preventing connection failures and stress-related issues, while maintaining a compact form factor.

Implementation Method 1

a solder resist disposed on the second main surface, and a metal film disposed on the second main surface, at least part of the metal film being covered by the solder resist such that an exposed part of the metal film is defined and serves as a heat dissipation terminal

Methodology Applied
Scientific EffectSolder resist masking:

Data Source

PatentEP3863073A1Light emitting device
Publication Date: 2021.08.11 NICHIA CORP
  • EP3863073A1 patent drawingFigure 1A~1B
  • EP3863073A1 patent drawingFigure 1C~2
  • EP3863073A1 patent drawingFigure 3A~3C

AI summary

A light emitting device includes a substrate having a first main surface that serves as the light extraction surface, a second main surface that is opposite the first main surface, and a mounting surface that is adjacent to at least the second main surface, and that is provided an insulating base material, a pair of connection terminals disposed on the second main surface, and a heat dissipation terminal disposed on the second main surface and between the pair of connection terminals; a light emitting element that is mounted on the first main surface of the substrate and; a sealing member that seals the light emitting element and is formed substantially in the same plane as the substrate on the mounting surface.