LED Hole Injection Structure With Mg Balls for Phosphor-Free Color Emission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional light emitting diodes (LEDs) face challenges in achieving efficient hole injection into the active layer, particularly for white LEDs without phosphors, which affects their efficiency and color implementation.
Innovation Solution
A light emitting diode with a novel hole injection structure featuring a second conductivity type semiconductor region with Mg balls, Al content, and varying doping concentrations, along with an electron blocking layer and contact layers, to enhance hole injection efficiency and enable the emission of various colors without phosphors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional active layer structure is used, then the device structure is simple, but hole injection efficiency into the active layer is insufficient
Solution Approach 1:
The second conductivity type semiconductor region is segmented into multiple functional layers: electron blocking layer, high-concentration doping layer, low-concentration doping layer, and contact layer. Each layer serves a specific function in hole injection and carrier management, resolving the contradiction by breaking down the complex hole injection function into manageable segments that can be optimized independently.
Solution Approach 2:
Different regions of the second conductivity type semiconductor region are assigned different doping concentrations and material compositions. The electron blocking layer has high Al content to block electrons, while the contact layer has optimized doping for electrical contact. This local differentiation of properties enables efficient hole injection without requiring complex overall restructuring.
2Adaptability or versatility
If multiple well layers are included to implement various colors without phosphor, then color implementation capability is improved, but carrier dynamics control becomes more difficult
Solution Approach 1:
The hole injection structure is designed and optimized in advance to ensure proper carrier dynamics before the multi-well layer active region operates. By pre-configuring the electron blocking layer, doping profiles, and contact structures, the system ensures that holes are efficiently injected and distributed across all well layers, enabling color versatility without requiring complex real-time control of carrier dynamics.
Solution Approach 2:
The low-concentration doping layer acts as an intermediary between the high-concentration doping layer and the active region. It facilitates smooth carrier transition and distribution across the multiple well layers, enabling efficient hole injection into all active regions while maintaining simple control architecture.
3Reliability
If the second conductivity type semiconductor region uses uniform doping, then manufacturing is simple, but hole injection efficiency is insufficient
Solution Approach 1:
The doping concentration parameter is varied across different layers of the second conductivity type semiconductor region. The electron blocking layer has high Al content with specific doping, the high-concentration doping layer has elevated Mg doping, and the low-concentration doping layer has reduced doping. This parameter variation optimizes hole injection efficiency at each interface and region, overcoming the limitations of uniform doping while maintaining manufacturability through systematic parameter control.
Data Source
AI summary
A light emitting device according to an embodiment of the present disclosure includes a first conductivity type semiconductor region; a second conductivity type semiconductor region; and a light emitting region disposed between the first conductivity type semiconductor region and the second conductivity type semiconductor region, in which the second conductivity type semiconductor region includes a plurality of regions including Mg balls.