Vertically coupled microring resonators using one epitaxial growth step and single-side lithography

Area of Science:

• Photonics and Optical Engineering
• Materials Science and Engineering

Background:

• Integrated photonic devices like microring resonators are crucial for optical communication and sensing.
• Existing fabrication methods for vertical microrings are often complex and multi-step.

Purpose of the Study:

• To propose a novel, simplified fabrication scheme for vertical microring resonators.
• To enable the integration of active and passive functionalities within microring structures.

Main Methods:

• Development of a fabrication process involving a single epitaxial growth and two single-side lithographic steps.
• Theoretical analysis of the impact of bus waveguide, coupling region, and ring structure parameters.
• Numerical calculations to predict device performance.

Main Results:

• The proposed scheme is the simplest reported fabrication method for vertical microrings to date.
• Numerical predictions indicate high-performance devices with quality factors exceeding 10000.
• The fabrication scheme supports integration of both active and passive regions.

Conclusions:

• The novel fabrication concept significantly simplifies the production of vertical microring resonators.
• This simplified approach facilitates the development of advanced microring lasers and other integrated photonic devices.