16-layer PCB with ENIG surface finish

16 layers
1.60mm thick
FR4 (370HR) material
Immersion gold
H OZ base copper on all layers
Min drill bit 0.20mm
Blue solder mask
All the small via holes are plugged with epoxy resin
Min. line width/space: 3.5/4.0mil
BGA pad size: 0.25mm
With impedance control