Corrugated Buried Heterostructure Laser With Single-Run MOCVD
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fabrication processes for corrugated buried heterostructure lasers are complex, lengthy, and result in poor quality blocking layers, hindering successful monolithic integration with photonic or optoelectronic components.
Innovation Solution
A method combining selective area growth (SAG), in situ MOCVD p-dopant diffusion, and etching techniques in a single MOCVD run to fabricate a corrugated buried heterostructure laser with lateral npnp blocking layers, reducing complexity and improving layer quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional fabrication processes with three or four epitaxial growth steps are used, then the laser structure can be formed, but the fabrication process becomes complex and lengthy
Solution Approach 1:
The patent combines multiple fabrication steps (epitaxial growth, doping, and etching) into a single integrated MOCVD process. The hollow corrugated structure serves as a template that enables simultaneous formation of the laser cavity, doping regions, and blocking layers through sequential in-situ operations, eliminating the need for separate processing steps and reducing overall process complexity
Solution Approach 2:
The dielectric layer is patterned into a hollow corrugated structure before the epitaxial growth begins. This pre-formed template defines the future laser cavity geometry and guides subsequent material deposition, allowing the active region and blocking layers to self-align during the epitaxial process without requiring additional alignment steps
2Reliability
If conventional fabrication processes with multiple epitaxial growth steps are used, then the laser structure can be formed, but the process becomes lengthy
Solution Approach 1:
The fabrication process maintains continuous in-situ operations within the MOCVD reactor. After the hollow corrugated structure is formed, the same reactor continuously performs epitaxial growth of the active region, in-situ doping with Zn, formation of blocking layers, and capping without requiring chamber evacuation or sample removal, thereby eliminating idle time between steps
Solution Approach 2:
Multiple functions (growth, doping, etching) are merged into a single continuous process flow. The patent integrates Zn diffusion doping and etching operations within the epitaxial growth sequence, allowing these traditionally separate steps to occur sequentially without interrupting the overall process continuity
3Reliability
If conventional fabrication processes are used, then the laser can be fabricated, but poor quality blocking layers are obtained
Solution Approach 1:
The hollow corrugated structure creates localized regions where blocking layers are formed only in specific areas (the ridges between corrugations). This spatially selective growth ensures that blocking layers are deposited with controlled thickness and composition exactly where needed, improving their quality for current confinement while leaving other regions unaffected
Solution Approach 2:
The hollow corrugated dielectric structure is formed in advance to serve as a mask and template. This pre-formed structure defines precise locations for blocking layer formation and ensures uniform deposition by guiding the epitaxial growth front, resulting in high-quality blocking layers with consistent properties
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 method simplifies the fabrication process and enhances the quality of blocking layers, enabling effective lateral current confinement and improved performance of corrugated buried heterostructure lasers.
Implementation Method 1
diffusing, in situ, a p-dopant in the substrate to obtain a p-dopant distribution in a portion of the substrate, the p-dopant distribution having a distribution profile being provided by the angles formed at the corresponding edges of the hollow corrugated structure
Implementation Method 2
metalorganic chemical vapour deposition (MOCVD) growth steps
Data Source
AI summary
There is provided a method for fabricating a corrugated buried heterostructure laser, including patterning a dielectric layer coating a substrate having a <0-11> direction to obtain a hollow corrugated structure. The hollow corrugated structure includes a central portion and regularly spaced-apart tabs laterally extending from the central portion and aligned with the <0-11> direction. The method also includes, in a single metal organic chemical vapour deposition run, forming an active region in the hollow corrugated structure to obtain the corrugated buried heterostructure laser. The single run combines selective area growth, p-dopant diffusion and etching techniques. There is also provided a corrugated buried heterostructure laser including a substrate having a <0-11> direction, a corrugated structure defined in the substrate and including a central portion and regularly spaced-apart tabs laterally extending from the central portion and aligned with the <0-11> direction, and an active region grown in the corrugated structure.