Multi-Cell LED with Segmented Connectors and Insulation Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Light emitting diodes (LEDs) with multiple cells connected in series face issues such as connector disconnection, limited heat dissipation, and potential difference-induced insulation breakdown, leading to reliability and efficiency problems.
Innovation Solution
A flip-chip shaped LED with a chip-scale package design, where connectors are strategically placed to minimize weak points, bump pads are distributed over each cell for enhanced heat dissipation, and the potential difference between bump pads and cells is controlled to prevent insulation breakdown, using a structure that includes a substrate with multiple light emitting cells, ohmic reflection layers, insulation layers, and carefully positioned pad metal layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If connectors are placed to connect multiple light emitting cells in series, then electrical connection between cells is achieved, but connector disconnection and damage occur due to substrate morphology
Solution Approach 1:
The patent divides the connector structure into multiple segments: a first connector portion on the lower insulation layer and a second connector portion on the upper insulation layer. This segmentation allows each portion to independently adapt to substrate morphology while maintaining electrical connection, preventing disconnection caused by substrate deformation.
Solution Approach 2:
The patent introduces an upper insulation layer as an intermediary structure that provides a stable platform for the second connector portion. This intermediary layer isolates the upper connector from direct contact with the deforming lower substrate, reducing stress and preventing disconnection.
2Temperature
If bump pads are disposed over light emitting cells for heat dissipation, then heat dissipation is improved, but high potential difference causes insulation breakdown
Solution Approach 1:
The patent designs the upper insulation layer to provide electrical isolation between the bump pad and the light emitting cell, creating equipotential regions. This prevents high potential difference from causing insulation breakdown while allowing the bump pad to remain in contact with the cell for heat dissipation.
Solution Approach 2:
The patent applies different properties to different regions: the lower insulation layer provides electrical isolation at the cell level, while the upper insulation layer provides isolation at the bump pad level. This localized quality approach allows heat dissipation contact in some regions while maintaining insulation in others.
3Productivity
If chip-scale package design is used to reduce size and simplify packaging, then manufacturing efficiency is improved, but heat dissipation and electrical connection challenges increase
Solution Approach 1:
The patent transitions from planar connection to three-dimensional stacked connection by placing connector portions on different insulation layers at different heights. This vertical arrangement enables multiple electrical connections within a compact footprint, maintaining reliability in the chip-scale package format.
Solution Approach 2:
The patent implements a nested structure where the first connector portion is embedded in the lower insulation layer and the second connector portion is embedded in the upper insulation layer, with the upper layer containing the lower layer's connection path. This nesting allows compact integration of multiple connection functions.
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 solution improves the reliability and light extraction efficiency of LEDs by preventing connector damage, ensuring effective heat dissipation, and maintaining electrical integrity, thereby enhancing the overall performance and lifespan of the LED.
Implementation Method 1
an ohmic reflection layer disposed on the second conductivity type semiconductor layer of each of the light emitting cells to form ohmic contact therewith
Implementation Method 2
an ohmic reflection layer disposed on the second conductivity type semiconductor layer of each of the light emitting cells to form ohmic contact therewith
Implementation Method 3
bump pads to secure good heat dissipation
Implementation Method 4
Light emitting diodes are generally used in the form of a package fabricated through a packaging process
Data Source
AI summary
A light emitting diode having a plurality of light emitting cells is provided. The light emitting diode according to an exemplary embodiment includes a lower insulation layer covering an ohmic reflection layer, connectors disposed on the lower insulation layer to connect the light emitting cells, and an upper insulation layer covering the connectors and the lower insulation layer. An edge of the lower insulation layer is spaced apart farther from an edge of the upper insulation layer than an edge of the light emitting cell. The lower insulation layer susceptible to moisture may be protected and reliability of the light emitting diode may improve.