Scientists develop hybrid laser technique to solve copper oxidation problem

Researchers from Zhejiang University, led by Prof. Kaichen Xu, have developed a new laser technique to solve the problem of copper oxidation in sensor systems.

The breakthrough could lead to safer, more durable equipment in industries such as aerospace, automotive, healthcare and transportation.

The team’s research, published in the International Journal of Extreme Manufacturing, introduces a hybrid direct laser recording method that enables the integration of copper and carbon sensors with thermoplastics.

These materials are used in many mission-critical devices, and this new technique enables real-time temperature monitoring, helping to ensure optimal performance and reliability over time.

Xu’s research group specializes in creating flexible electronic devices that can be used in extreme conditions or in wearable and implantable devices.

Their work focuses on developing new manufacturing techniques and multifunctional devices using hybrid laser platforms that can perform multiple tasks.

Copper Oxidation Problem

Copper (Cu) is an essential element in sensor systems due to its good conductivity and low cost.

However, it oxidizes easily during and after processing, which affects its durability. Copper oxidation can reduce the performance and life of sensors, making them less reliable in the long term.

To overcome this problem, Prof. Xu’s team developed a single-step photothermal treatment that makes copper resistant to oxidation, even at high temperatures of up to 170°C. The process ensures that the copper can last longer without degrading, making it ideal for use in extreme conditions.

Hybrid Laser Process

The researchers’ new method consists of two main steps:

1. Making Copper Connections: They used a continuous-wave (CW) laser to photothermally reduce and passivate copper oxide (CuO). This step helped create extremely durable copper connections that were resistant to oxidation.
2. Forming carbon sensors: The team used an infrared (IR) laser to create laser-induced carbon (LIC) sensors from a thermoplastic substrate. These sensors can monitor temperature and other environmental conditions in real time.

This process simultaneously reduced, sintered, and passivated the copper, making it more resistant to high temperatures. Sensors created by this process were tested for their ability to monitor temperature under a variety of conditions, proving durable and reliable.

Potential Applications

This new laser technique has potential applications in a wide range of industries, including aerospace, automotive, high-speed rail and medical equipment.

The integrated sensor system is a lightweight and durable solution that enables real-time monitoring of temperature and other environmental factors.

Prof. Xu’s team is also working to expand the system to enable monitoring of additional factors such as pressure, strain and humidity.

Their ultimate goal is to develop advanced techniques for manufacturing high-quality electronic devices that can be used on curved surfaces, enabling even more flexible and innovative applications.

This breakthrough brings us one step closer to creating better, more durable sensors that can operate in extreme conditions, delivering significant safety and performance benefits across a range of industries.

Source: KSR.