Group III Nitride Semiconductor Light Emitting Element
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional group III nitride semiconductor light emitting elements suffer from well layers with different emission wavelengths, leading to deterioration in color purity and reduced emission intensity due to varying piezooptical effects and carrier concentrations.
Innovation Solution
The light emitting layer is designed with multiple well layers formed to coincide in emission wavelength, with varying InGaN composition ratios, doping amounts, or thicknesses, ensuring uniformity and alignment with p- and n-semiconductor layers to enhance emission characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If well layers are designed with different composition ratios to achieve broader emission coverage, then emission intensity increases, but color purity deteriorates due to different emission wavelengths
Solution Approach 1:
The patent applies parameter changes by systematically varying the InGaN composition ratio, well layer thickness, and Si doping amount across different well layers. Specifically, the In composition ratio decreases from 0.26 to 0.14 in steps, while thickness decreases from 42Å to 21Å and Si doping increases from 1×10^18 to 7×10^18 atoms/cm³. These coordinated parameter changes compensate for piezooptical effects and carrier concentration variations, ensuring all well layers emit at the same wavelength (460-463nm) despite structural differences, thereby maintaining color purity while achieving high emission intensity through multiple contributing layers.
2Adaptability or versatility
If well layers have different piezooptical effect levels and carrier concentrations, then emission wavelength varies between layers, but this causes deterioration in color purity
Solution Approach 1:
The patent applies local quality by creating spatially varying properties within the MQW structure. Each well layer has locally optimized characteristics: the first well layer (nearest n-semiconductor) has higher In content (0.26) and lower Si doping (1×10^18), while the fourth well layer (nearest p-semiconductor) has lower In content (0.14) and higher Si doping (7×10^18). This local differentiation compensates for the cumulative piezooptical effects and carrier concentration gradients that increase from n- to p-side, ensuring uniform emission wavelength (460-463nm) across all layers despite their different local conditions.
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 approach achieves excellent color purity and increased emission intensity by ensuring all well layers emit at the same wavelength, resulting in a sharper emission spectrum and enhanced light output.
Implementation Method 1
a light emitting layer comprising a multiquantum well structure comprising a group III nitride semiconductor
Implementation Method 2
the screening effect is different between the well layers due to a difference in piezooptical effect level and in carrier concentration therebetween
Data Source
AI summary
A group III nitride semiconductor light emitting element, comprising having a light emitting layer with a multiquantum well structure formed of a group III nitride semiconductor. The light emitting layer has plural well layers, and the plural well layers are formed to coincide in emission wavelength with each other.