Rapid fabrication of customizable periodic structures using DMD-Dammann interference lithography.

Area of Science:

• Photonics and Nanofabrication
• Optical Engineering
• Materials Science

Background:

• Direct digital micromirror device (DMD) lithography offers flexibility but can be limited by energy efficiency and resolution.
• Multi-beam interference techniques provide high resolution but often require complex setups and masks.
• Fabricating complex periodic structures for photonic devices demands efficient and scalable methods.

Purpose of the Study:

• To introduce a hybrid lithography approach integrating DMD projection with Dammann grating multi-beam interference.
• To demonstrate the rapid fabrication of complex two-dimensional periodic structures with reduced exposure dose.
• To explore the tunability and scalability of this novel lithography technique for photonic applications.

Main Methods:

• Hybrid lithography combining DMD projection and Dammann grating multi-beam interference.
• Utilizing DMD image modulation, grating angle adjustment, and exposure dose control for pattern tunability.
• Experimental fabrication and characterization of periodic structures and photonic crystal waveguides.

Main Results:

• Successful fabrication of periodic dot arrays, gradient-duty-ratio superlattices, and photonic crystal waveguides (beam splitters, bends, resonant rings).
• Achieved a 25-fold improvement in energy efficiency compared to conventional direct DMD lithography.
• Demonstrated tunability of patterned structures through key process parameters.

Conclusions:

• The DMD-Dammann interference lithography is a versatile and scalable method for fabricating complex photonic structures.
• This hybrid approach offers high energy efficiency and simplified design for high-throughput manufacturing.
• The technique shows significant potential for producing photonic crystal devices and optical microarrays.