Terahertz Rectangular Waveguides by UV-LIGA with Megasonic Agitation

Area of Science:

• Terahertz technology
• Microwave engineering
• Materials science

Background:

• Rectangular waveguides are crucial components in terahertz systems.
• Fabrication challenges include achieving high precision and smooth internal surfaces.
• UV-LIGA offers a potential solution for micro-scale waveguide manufacturing.

Purpose of the Study:

• To research and develop a WR2.8 terahertz rectangular waveguide using UV-LIGA technology.
• To optimize fabrication parameters for dimensional accuracy and surface quality.
• To demonstrate a reliable method for removing sacrificial layers without damaging the waveguide structure.

Main Methods:

• Fabrication via UV-lithography, electroplating, and molding (UV-LIGA).
• Application of megasonic agitation to enhance mechanical properties and reduce internal surface roughness.
• Optimization of process parameters for precise geometry control.
• Development of a synthesis method for damage-free removal of SU-8 photoresist.

Main Results:

• Achieved dimensional accuracy of 5 µm for height and 2 µm for width.
• Measured internal surface roughness of 79.6 nm.
• Successfully demonstrated the fabrication of a WR2.8 waveguide operating from 260 GHz to 400 GHz.
• Validated results through experimental measurements and numerical simulations.

Conclusions:

• UV-LIGA technology, with optimized parameters and megasonic agitation, is effective for fabricating high-precision WR2.8 terahertz waveguides.
• The developed SU-8 removal method ensures structural integrity.
• The fabricated waveguides exhibit excellent dimensional accuracy and surface quality suitable for terahertz applications.