Communication—A self-contained temperature sensing approach for ultrafast microwelding

Temperatures during ultrafast microwelding processes are very difficult to be measured timely and accurately. Here, we develop a self-contained temperature sensing approach using thermoelectric voltages between dissimilar welded materials. This approach can offer response speeds ranging from kilohertz to megahertz (temporal resolution of sub-millisecond scales) without requiring external thermocouples. Thus, it was successfully used to monitor temperature profiles for the resistance microwelding processes accomplished within 1 millisecond. This approach provides a promising tool for micro/nanoscale ultrafast welding methods to control the welding quality as well as explore the welding mechanism in micro/nanosystem integration and packaging.