Buried Waveguide Taper for III-V to Silicon Mode Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Challenges exist in integrating III-V semiconductor technology with silicon-based platforms to leverage the beneficial characteristics of both, particularly in optoelectronic applications.
Innovation Solution
A waveguide structure comprising a semi-insulating buried heterostructure (SIBH) with a non-tapered and tapered section, buried in a thermally conductive cladding and separated by a dielectric layer, allowing for efficient optical signal transition between waveguides.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If III-V semiconductor waveguide is integrated with silicon-based platform, then optoelectronic performance is improved, but thermal management and optical mode matching become problematic
Solution Approach 1:
The patent introduces a tapered section as an intermediary transition region between the III-V semiconductor waveguide and the silicon-based waveguide. This tapered section gradually transforms the optical mode from the III-V waveguide to match the silicon waveguide mode, serving as a mediator that facilitates efficient optical coupling while managing the complexity of hetero-integration.
Solution Approach 2:
The patent applies different structural characteristics to different sections of the waveguide: the non-tapered section maintains the original III-V semiconductor properties for optimal optoelectronic performance, while the tapered section provides gradual geometric transformation for mode matching. This local differentiation resolves the contradiction by optimizing each region for its specific function.
2Productivity
If tapered section is added for optical mode transition, then optical coupling efficiency is improved, but back reflection increases
Solution Approach 1:
The patent incorporates an anti-reflection coating on the tapered section before optical coupling occurs. This preliminary action prevents back reflection from being generated in the first place, allowing the tapered section to maintain high optical coupling efficiency without suffering from the harmful back reflection effect.
3Temperature
If thermally conductive cladding is used, then thermal diffusion is improved, but optical loss increases due to refractive index mismatch
Solution Approach 1:
The patent applies the thermally conductive cladding selectively to specific regions of the waveguide structure rather than uniformly across all sections. This localized application ensures that thermal management is optimized where needed while minimizing the impact on optical propagation, thereby reducing optical loss caused by refractive index mismatch in the optical active regions.
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
Enhances thermal conductivity and reduces back reflection, enabling efficient optical mode transfer and improved thermal diffusion, suitable for semiconductor optical amplifiers, lasers, photodiodes, and modulators.
Implementation Method 1
the non-tapered section and the tapered section are at least partially buried in the thermally conductive cladding
Implementation Method 2
the dielectric layer has a lower refractive index than the second waveguide
Data Source
Figure 1A
Figure 1B
Figure 1C
AI summary
There is provided a waveguide structure and a method of manufacturing a waveguide structure. The waveguide structure comprises a first waveguide 102 arranged on a substrate 104 and comprises a non-tapered section 150 and a tapered section 152. The waveguide structure comprises a second waveguide 110. The second waveguide is under the first waveguide in the substrate and arranged for transition of an optical signal from/to the first waveguide to/from the second waveguide. The non-tapered section and the tapered section of the first waveguide are at least partially buried in a thermally conductive cladding 112. A dielectric layer 114 is arranged between the tapered section and the thermally conductive cladding and has a lower refractive index than the second waveguide.