LED module production places extremely high demands on Solder Paste's wetting ability, thermal stability, and residue transparency. Especially on narrow-pitch QFN/DFN pads, insufficient activity of LED Solder Paste or uneven particle size distribution of alloy powder can easily lead to cold solder joints, tombstoning, and solder balls. On a certain 3528 strip light module production line, after replacing a certain Japanese T4 Solder Paste with 8MQP/5RQ, the first-pass yield increased from 92.7% to 99.1%. Its 0307 alloy powder T4 formulation and ROL1 halogen-free design ensure the Flux volatilizes fully at a peak temperature of 245°C, with transparent residue, fully meeting the optical cleanliness requirements of module solder paste.

For high thermal cycling scenarios such as automotive LED modules, the measured void rate of 8M9P/5RR zero-halogen module solder paste is stably controlled within 3.2%. Combined with the melting point consistency of 305 alloy powder T4 and reflow spreading tension, the thickness fluctuation of the solder joint IMC layer is less than ±0.8μm. On the same production line, after switching to 8MTSP/5RTS, the void rate rose to 6.7%, indicating that while halogen content below 500ppm can reduce corrosion risk, the ROL0 zero-halogen formulation provides better thermal stress relief, which is the key process window for Domestic Solder Paste to break through in high-end LED modules.

Lighting LED modules generally use larger pad pitches. In such cases, the SC07 and 00507BN dual alloy powder combination of the 8MA series LED solder paste demonstrates obvious cost advantages. The gradient distribution of 65% T3 powder and 35% T4 powder increases the printing release rate by 12%, and the post-solder residue has a light transmittance of over 91% at a 450nm wavelength, avoiding color temperature drift caused by flux yellowing after module SMT. After a certain outdoor street lamp factory switched in bulk, the rework rate decreased by 0.47 percentage points, and the production line no longer needs an additional plasma cleaning station.

Water-washable LED solder paste is irreplaceable in aluminum substrate LED modules. 8MW1P/5RW1 paired with 0307 alloy powder T4, under spray pressure of 0.25MPa and water temperature of 45°C, can reach an ionic contamination value of <0.78μg/cm² NaCl equivalent after three cleaning cycles. When 8MW1AP/5RW1A is used for the Sn42Bi58 low-temperature system, the wetting angle on nickel-plated aluminum fins can be reduced to 28°, with no white salt precipitation traces on the post-solder surface, which is crucial for the long-term thermal resistance stability of heat sink-integrated LED modules.

Laser soldering LED modules are rapidly gaining popularity. The 5RLJ series laser lead-free high-temperature solder paste is compatible with jet valve dispensing accuracy of ±25μm. The 00507B2N alloy powder T6 has a melting response time of only 0.83 seconds at a laser power density of 120W/cm², with a solder ball occurrence rate below 0.003%. When 5RLJB-4258 is used for soldering COB direct-insert LED brackets, forming can be completed at 160°C low-temperature reflow, while the solder joint shear force remains above 3.2N, indicating that Domestic Solder paste in the LED solder paste segment has already covered the full process chain from high temperature to ultra-low temperature, and from traditional printing to laser dispensing.