Research on Efficient Charging and Highly Reliable Non-Contact Welding Sealing Technology for Ultra-Thin Silicon-Based Vapor Chambers

In recent years, with the trend towards miniaturization and integration of integrated circuits (IC), the emergence of high-temperature hotspots has become a key challenge restricting the enhancement of chip performance, urgently requiring effective thermal management solutions. Directly integrating Vapor Chambers (VC) onto electronic devices is an effective means to address hotspot issues. However, the thermal mismatch between traditional metal-made VC and semiconductor materials lead to suboptimal performance. Although the use of Thermal Interface Materials (TIM) can alleviate the effects of thermal mismatch, this approach introduces additional thermal resistance, affecting thermal management efficiency. Therefore, silicon-based VC, with their similar thermal expansion coefficients to semiconductor materials, demonstrate significant advantages and broad prospects. This paper designs and manufactures silicon-based VC with Ni pads and establishes a Charging system that uses steam to remove non-condensable gases and deionized water as the working fluid. After Charging, the Ni pads are heated by induction to melt Sn95Ag5 alloy solder, sealing the Charging port. The results show that the VC sample successfully Charged with 80 μl of deionized water, with an error range controlled within ±5 μl. Under the condition of 100°C, after continuous operation for 96 h, there were no issues of working fluid leakage from the VC sample. This study proposes an effective method for Charging and sealing silicon-based VC, avoiding the need to weld Charging tubes at the VC Charging port, thereby simplifying the testing process. This is significant for promoting the practical application of silicon-based VC cooling technology.