N-type Third Semiconductor Layer Electrode for Light Emitting Apparatus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor lasers with nano-structures suffer from light loss due to the high light absorption coefficient of traditional electrodes like ITO, which limits their efficiency in confining and propagating light.
Innovation Solution
A light emitting apparatus with a laminated structure that uses an n-type third semiconductor layer as an electrode, forming a tunnel junction with a p-type second semiconductor layer, reducing light absorption and enabling efficient current injection into light emitting layers without the need for a transparent electrode like ITO.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a transparent electrode made of ITO is used to cover the nano-columns, then the electrical connection is achieved, but the light propagating between the nano-columns is greatly lost due to the large light absorption coefficient of ITO
Solution Approach 1:
The patent changes the material parameter from ITO (high light absorption) to a semiconductor layer (low light absorption). The n-type third semiconductor layer is introduced with specifically controlled doping concentration (1×10^18 to 1×10^20 cm^-3) to achieve both electrical conductivity and low light absorption, directly resolving the contradiction between electrical connection and light loss.
2Productivity
If the light emitting layer and first semiconductor layer form a columnar section with nano-structure, then the light emission efficiency is improved based on photonic crystal effect, but the light propagating between the nano-columns leaks to the electrode and cannot be completely confined
Solution Approach 1:
The n-type third semiconductor layer acts as an intermediary between the light emitting layer and the electrode. It provides a low-absorption pathway for light propagation while maintaining electrical connection, preventing light from leaking directly to the high-absorption ITO electrode. This mediator resolves the contradiction between achieving electrical connection and preventing light leakage.
3Productivity
If a tunnel junction layer is introduced between the p-type second semiconductor layer and n-type third semiconductor layer, then the current injection efficiency is improved, but the device structure becomes more complex
Solution Approach 1:
The n-type third semiconductor layer serves multiple functions: it acts as part of the tunnel junction structure for efficient current injection, provides a low-absorption medium for light propagation, and maintains electrical connection. By combining multiple functions in one layer, the patent achieves high current injection efficiency while minimizing the increase in structural complexity.
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 minimizes light loss and maintains low electrical resistance, enhancing the efficiency and performance of the light emitting apparatus by using the n-type third semiconductor layer as an electrode with a small light absorption coefficient.
Implementation Method 1
the p-type second semiconductor layer is joined in the form of a tunnel junction to the n-type third semiconductor layer
Implementation Method 2
a light emitting layer
Data Source
AI summary
A light emitting apparatus includes an electrode and a laminated structure. The laminated structure includes an n-type first semiconductor layer, a light emitting layer, a p-type second semiconductor layer, a tunnel junction layer, and an n-type third semiconductor layer. The electrode is electrically connected to the first semiconductor layer. The first semiconductor layer, the light emitting layer, the second semiconductor layer, the tunnel junction layer, and the third semiconductor layer are arranged in a presented order. The light emitting layer and the first semiconductor layer form a columnar section.