User-defined microstructures array fabricated by DMD based multistep lithography with dose modulation.

Area of Science:

• Microfabrication and Nanotechnology
• Optical Engineering
• Materials Science

Background:

• Fabricating user-defined microstructures with precise control over spatial distribution and shape is challenging.
• Existing lithography methods may lack flexibility or resolution for diverse microstructure arrays.

Purpose of the Study:

• To propose and demonstrate a flexible and efficient digital micromirror devices (DMD) based multistep lithography (DMSL) strategy.
• To enable the fabrication of user-defined microstructures with arbitrary shapes and customized distributions.
• To explore the application of DMSL in creating microlens arrays.

Main Methods:

• Utilizing digital micromirror devices (DMD) for flexible pattern generation.
• Implementing dose modulation and high-resolution step movement via a piezoelectrical stage (PZS).
• Combining DMSL with thermal reflowing for microlens array fabrication.

Main Results:

• Successful fabrication of 2D lattices with periodic/nonperiodic spatial distributions and arbitrary shapes.
• Achieved critical feature sizes down to 600 nm.
• Demonstrated the creation and characterization of square and hexagonal microlens arrays with customized distributions.

Conclusions:

• DMSL provides a versatile and efficient approach for microfabrication.
• The method allows for precise control over microstructure design and spatial arrangement.
• DMSL holds significant potential for manufacturing functional microstructures arrays, including microlens arrays.