High-level integration of three-dimensional microcoils array in fused silica

Area of Science:

• Micromachining and microfabrication technologies.
• Materials science and engineering.
• Microfluidics and lab-on-a-chip systems.

Background:

• Fabricating three-dimensional (3D) microcoil arrays on lab-on-a-chip platforms presents significant challenges in micromachining.
• Existing methods often lack the speed, precision, or integration required for practical applications.

Purpose of the Study:

• To develop a facile and rapid method for fabricating 3D microcoil arrays within fused silica.
• To demonstrate the fabrication of high-density and uniform microcoil arrays for potential device applications.

Main Methods:

• Utilized an improved femtosecond-laser wet-etch (FLWE) technology combined with a metal-microsolidifying process.
• Fabricated 3D microcoil arrays, including 3x3 O-shaped and 4x4 linear configurations, inside fused silica substrates.
• Employed a high-melting-point alloy for robust electrocircuit formation within the microcoils.

Main Results:

• Successfully fabricated 3D microcoil arrays with good uniformity and a high integration level.
• Demonstrated the ability to create complex microcoil structures (O-shaped and linear) using the developed method.
• Ensured the integrity of the electrocircuit by injecting a high-melting-point alloy, preventing disconnections.

Conclusions:

• The improved FLWE and metal-microsolidifying process offers an efficient route for 3D microcoil array fabrication.
• The fabricated microcoil arrays exhibit promising characteristics for real-world device applications in lab-on-a-chip systems.
• This technique addresses key challenges in micromachining for advanced microelectronic and microfluidic devices.