Semiconductor Light Emitting Device Electrode Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor light emitting devices face challenges in achieving high light extraction efficiency due to limitations in electrode design and reflectance, leading to inefficient light reflection and emission.
Innovation Solution
The semiconductor light emitting device incorporates a semiconductor layer with a light emitting layer between two surfaces, featuring a silver electrode on one surface with a large contact area and an insulating film between the electrode's end part and the surface, along with aluminum electrodes for enhanced reflectance and current distribution, improving light extraction efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the electrode with high light reflectance is spread with a large area on the one surface side, then the light extraction efficiency is improved, but the current distribution becomes non-uniform and concentrates at the edge portions
Solution Approach 1:
The patent applies local quality by creating different regions within the reflective electrode: a first electrode region with high reflectance for light extraction, and a second electrode region with lower reflectance for uniform current distribution. This spatial differentiation of electrode properties resolves the contradiction between maximizing light extraction and maintaining current uniformity.
Solution Approach 2:
The electrode is segmented into multiple functional regions: a first reflective electrode for light extraction and a second electrode for current distribution. This segmentation allows each region to optimize its specific function without compromising the other, addressing the technical contradiction between light extraction efficiency and current distribution uniformity.
2Productivity
If the electrode area is increased to improve light reflection, then more light can be extracted, but the manufacturing precision and alignment become more difficult
Solution Approach 1:
The patent introduces a third dimension (vertical stacking) by forming electrodes at different heights on the semiconductor layer. The first electrode is formed on a raised portion while the second electrode is formed on a lower level, connected via an insulating film. This dimensional separation allows both electrodes to have large areas without compromising alignment precision, as their positions are defined in multiple dimensions rather than competing in a single plane.
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 configuration enhances light extraction efficiency by utilizing high reflectance materials and optimizing current distribution, resulting in improved emission intensity uniformity and device reliability.
Implementation Method 1
a light of the light emitting layer can be reflected by the electrode and extracted from the other surface side
Data Source
AI summary
The semiconductor layer has a first surface, a second surface provided on opposite side from the first surface, and a third surface provided on the opposite side from the first surface with a step difference with respect to the second surface. The semiconductor layer includes a light emitting layer between the first surface and the third surface. The first electrode is in contact with the second surface. The second electrode is provided in a plane of the third surface. The second electrode includes a contact part in contact with the third surface and an end part not in contact with the third surface. The second electrode contains silver. The insulating film is provided between the end part of the second electrode and the third surface. A semiconductor light emitting device having a high light extraction efficiency is provided.