In high-frequency technology fields such as 5G communication and millimeter-wave radar, printed circuit boards serve as the core carrier, and their performance directly determines the operational accuracy of the equipment. These scenarios place stringent requirements on the consistency of the dielectric constant of PCBs. Flux residue-induced electromagnetic property variations become a key bottleneck restricting performance, making ultrasonic residue-free soldering technology a core industry solution.
High-frequency signal transmission is extremely sensitive to the stability of the dielectric properties of PCBs. In the millimeter-wave band at 20kHz and above, even small fluctuations in the dielectric constant can lead to signal impedance mismatch, increasing transmission loss and even signal distortion. Data shows that high-frequency substrates need to control the dielectric constant deviation within ±0.05 to meet the accuracy requirements of 60kHz automotive radar. In traditional soldering, residual polymerized rosin and reactive salts from the flux directly alter the local dielectric environment, causing shifts in capacitance and inductance parameters, resulting in communication frequency drift or shortened radar detection range. More seriously, residues, after absorbing moisture, can lower insulation resistance and accelerate electrochemical migration, posing safety hazards to equipment operation.
Ultrasonic residue-free soldering technology overcomes this challenge through physical principles. Its core utilizes high-frequency mechanical vibration (20kHz-60kHz) to generate molecular frictional heat at the soldering interface under pressure, achieving solid-state bonding of materials. The entire process requires no flux or solder, avoiding chemical residues from the outset. Compared to traditional soldering, this "consumable-free" process not only eliminates the interference of residues on dielectric properties but also controls the soldering time to within 0.05-1.5 seconds, with a minimal heat-affected zone, effectively protecting the physical stability of the high-frequency substrate.
As high-frequency technology develops towards wider frequency bands and higher integration levels, the requirements for cleanliness and precision in printed circuit board manufacturing continue to escalate. Ultrasonic residue-free soldering, with its pollution-free, high-precision, and high-efficiency characteristics, not only solves the problem of dielectric constant consistency but also aligns with the trend of green manufacturing. This "silent welding" technology is becoming a standard feature in high-end manufacturing fields such as 5G communication and autonomous driving, providing a solid guarantee for the performance breakthrough of high-frequency electronic equipment.
