PCB Specification：
Type：High-density interconnection
14 Layer
Thickness: 2.5+/-0.2mm
Material: RO4350B,RO4450F, Isola PCL-370HR 
Via-in-pad and POFV design
Sequential board: 4X lamination with one ply RO4450F pre-pp between core and core
Surface finish: ENIG （0.5mmBGA pad pitch，0.8mm hole pitch）