Superlattice Semiconductor Layer for Smoother Active-Layer Stress Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor devices experience surface roughness of the semiconductor layer, leading to excessive stress on the active layer, which deteriorates electrical and optical characteristics.
Innovation Solution
A semiconductor device is designed with a first conductive semiconductor layer that includes a first superlattice layer with alternately disposed sub-layers, emitting ions of indium, aluminum, and dopants when primary ions are irradiated, thereby improving surface roughness and stress relief on the active layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional semiconductor layer structure is used, then the device structure is simple, but the surface roughness increases causing excessive stress on the active layer
Solution Approach 1:
The semiconductor layer is segmented into multiple sub-layers (first sub-layer, second sub-layer, third sub-layer) with different compositions and thicknesses. This segmentation allows each sub-layer to serve specific functions: the first sub-layer provides a smooth surface, the second sub-layer controls stress, and the third sub-layer enables doping, thereby resolving the contradiction between surface roughness and structural simplicity.
Solution Approach 2:
Different regions of the semiconductor layer are assigned different local qualities through varying composition ratios of group III elements and nitrogen content. The first sub-layer has a composition optimized for surface smoothness, the second for stress management, and the third for electrical doping, allowing each region to optimize its local function rather than using a uniform structure.
2Stress or pressure
If the semiconductor layer is made thicker to reduce stress, then stress relief improves, but the surface roughness increases
Solution Approach 1:
The thick semiconductor layer is divided into multiple thin sub-layers, each with controlled thickness. This segmentation allows the total thickness to be sufficient for stress relief while maintaining individual sub-layer thicknesses that prevent surface roughness accumulation, effectively decoupling the stress relief function from the surface quality issue.
Solution Approach 2:
The composition ratio of group III elements and nitrogen content are varied across different sub-layers to independently control stress and surface morphology. By adjusting these parameters locally in each sub-layer, the patent achieves both stress relief and surface smoothness simultaneously.
3Reliability
If dopant concentration is increased to improve electrical characteristics, then conductivity improves, but surface roughness and stress increase
Solution Approach 1:
The doped region is segmented into a separate third sub-layer distinct from the surface-forming first sub-layer and stress-controlling second sub-layer. This segmentation confines the dopant concentration effects to a specific region, allowing high doping for electrical performance without compromising the surface roughness of the first sub-layer.
Solution Approach 2:
High dopant concentration is applied locally in the third sub-layer where electrical conductivity is needed, while the first and second sub-layers maintain their respective optimizations for surface smoothness and stress control. This local quality differentiation resolves the contradiction between electrical performance and surface quality.
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 improved surface roughness and stress relief enhance optical power and current spreading efficiency in the semiconductor device.
Implementation Method 1
the semiconductor structure emits ions of indium, aluminum, a first dopant, and a second dopant when primary ions are irradiated thereon
Data Source
AI summary
A semiconductor device includes a semiconductor structure including a first conductive semiconductor layer, a second conductive semiconductor layer disposed on the first conductive semiconductor layer, and an active layer disposed between the first conductive semiconductor layer and the second conductive semiconductor layer. The first conductive semiconductor layer includes a first superlattice layer including a plurality of first sub layers and a plurality of second sub layers, and a first sub layer of the plurality of first sub layers and a second sub layer of the plurality of second sub layers are alternately disposed. The semiconductor structure includes a composition of a first dopant which is a n-type dopant.