Metamaterial-Engineered Silicon Beam Splitter Fabricated with Deep UV Immersion Lithography

Area of Science:

• Photonics and Metamaterials
• Nanofabrication and Device Engineering

Background:

• Subwavelength grating (SWG) metamaterials offer unique light manipulation capabilities.
• Fabrication challenges, particularly minimum feature size and scalability, limit practical applications of SWG devices.
• Existing SWG realizations often depend on electron-beam lithography, hindering high-volume manufacturing.

Purpose of the Study:

• To experimentally demonstrate a high-performance SWG metamaterial beam splitter.
• To overcome fabrication limitations by utilizing deep-ultraviolet immersion lithography.
• To enable scalable silicon photonic circuits through flexible metamaterial engineering.

Main Methods:

• Fabrication of an SWG metamaterial beam splitter using 300-mm silicon-on-insulator (SOI) technology.
• Implementation of deep-ultraviolet (DUV) immersion lithography for precise patterning.
• Characterization of the beam splitter's performance across a broad optical bandwidth.

Main Results:

• Successful fabrication of an SWG metamaterial beam splitter using scalable DUV immersion lithography.
• Demonstration of high performance with a measured bandwidth exceeding 186 nm.
• Operation centered at a key telecommunication wavelength of 1550 nm.

Conclusions:

• Deep-ultraviolet immersion lithography enables scalable fabrication of advanced SWG metamaterials.
• The demonstrated SWG beam splitter achieves high performance and broad bandwidth.
• This work facilitates the development of scalable silicon photonic integrated circuits using metamaterial designs.