20-Layer Multilayer PCB with Blind Vias

A 20-layer multilayer PCB with blind vias, board thickness 2.7mm. Blind vias connect an outer layer to one or more inner layers without going through the entire board, freeing the opposite face for dense component placement and shortening high-speed signal paths. Combined with 20 functional layers, this gives the layout team enough room to separate power, ground and signal planes cleanly, place multiple controlled-impedance reference planes, and break out fine-pitch BGAs that a pure through-hole stackup could not handle. The 2.7mm thickness provides backplane-class mechanical rigidity while still supporting blind-via aspect ratios within standard process windows. Used in telecom backplane modules, datacenter switch and storage boards, AI server modules, industrial controllers and aerospace electronics.