Immersion gold multilayer board

Immersion gold multilayer board.  Material FR4 S1141. Board thickness 1.2mm. Surface treatment according to IPC-4552, Immersion gold, AU: 2-4U",NI: 118-236u".  Inner layer 1oz and outer layer 1oz. Min hole copper thickness according to IPC-II, average 20um. Green soldermask and white silkscreen.
Immersion gold is our most common surface treatment because its surface is smooth and easy to weld components. Customers will also give priority to their pcb products using ENIG. The thickness of the immersion gold board can be from 0.2mm to 5 mm. and the sizes can be from 5*5mm to 500*550mm. This kind of surface finished Suitable for both samples and batches.