Scalable Fourier transform system for instantly structured illumination in lithography

Area of Science:

• Optics and Photonics
• Nanotechnology
• Materials Science

Background:

• Structured illumination is crucial for high-resolution patterning in lithography.
• Existing methods for generating complex interference patterns can be slow or lack scalability.
• The need for dynamic control over fringe characteristics (frequency, orientation, phase) is increasing for advanced material fabrication.

Purpose of the Study:

• To develop a unique, scalable Fourier transform 4-f system for instant structured illumination.
• To demonstrate the system's capability for dynamic generation of interference fringes with controllable parameters.
• To adapt this system for lithography to produce pixelated nano-fringe arrays with space-variant properties.

Main Methods:

• Utilized a Fourier transform 4-f optical system.
• Integrated a 1-D grating and a phase retarder to generate ±1st order diffracted light.
• Manipulated grating and phase retarder to control fringe frequency, orientation, and phase shifts.
• Applied the system in photolithography for direct patterning of photoresist.

Main Results:

• Achieved instant generation of interference patterns within a constant area.
• Demonstrated dynamic control over fringe frequencies, orientations, and phase shifts.
• Successfully produced pixelated nano-fringe arrays with arbitrary frequencies and orientations in photoresist.
• Attained high variation resolution in the patterned structures.

Conclusions:

• The developed scalable Fourier transform system offers instant and versatile structured illumination for lithography.
• The system enables dynamic fabrication of space-variant nanostructures with high precision.
• This technology holds significant promise for the large-area production of functional materials requiring tailored nanostructures.