產品規格

Peelable S/M 2Layers Lead Free HASL FR4

Product Description

Damage from additional thermal deviation

Coplanarity issues due to pad-to-pad coating thickness variations

Potential coplanarity issues with HASL finishes

Stencil spacer issues are related to differences in coating thickness and mushroom cap profile (coating) on small pads.

The difference in solder coating thickness for lead-free HASL coatings is typically about half the thickness of tin-lead HASL coatings. In this finish, coplanarity is also good. Modern HASL lines are designed to provide operating conditions consistent with other equipment in modern cardboard workshops to avoid heat and smoke problems.

Due to the higher surface tension of lead-free solder, the coating formed in the HASL process is thin and uniform compared to tin-lead solder formed under similar conditions.

The coating thickness can be checked by XRF (X-ray Fluorescence Spectroscopy) technology.

Compressive stress is the driving force for whiskers (filaments protruding from the surface of a board with tin as the final finish).

Lead Free HASL offers a corrosion-resistant finish that ensures long-term solderability.

For more details about PCB Design, please contact us.