High-Performance Flexible Thermoelectric Power Generator Using Laser Multiscanning Lift-Off Process

Area of Science:

• Materials Science
• Energy Harvesting
• Nanotechnology

Background:

• Flexible thermoelectric generators (f-TEGs) are crucial for self-powered sensors in the Internet-of-Things (IoT) era.
• Developing robust and efficient f-TEGs is essential for next-generation smart network monitoring systems.

Purpose of the Study:

• To report a novel fabrication method for flexible thermoelectric generators (f-TEGs) using screen-printing and laser lift-off.
• To evaluate the flexibility and power output performance of the fabricated f-TEGs.

Main Methods:

• Screen-printing technique (SPT) for fabricating the thermoelectric generator (TEG) on a SiO2/a-Si/quartz substrate.
• Laser multiscanning (LMS) lift-off process using a XeCl excimer laser to separate the TEG from the quartz substrate via selective reaction with the a-Si exfoliation layer.

Main Results:

• Fabrication of a prototype f-TEG with an array of 72 TE couples.
• Demonstrated high flexibility across various bending radii.
• Achieved excellent output performance: 4.78 mW/cm² and 20.8 mW/g at ΔT = 25 °C.
• Exhibited no significant performance degradation after 8000 bending cycles.

Conclusions:

• The developed SPT and LMS techniques provide an effective method for producing high-performance, flexible thermoelectric generators.
• The fabricated f-TEGs show great potential for applications in self-powered sensors and IoT devices.
• The durability and consistent performance under repeated bending highlight the robustness of the fabrication process.