Introduction: substantial-density HDI PCBs for optical conversation call for precise 3 mil/3 mil trace/Place, Rogers or Panasonic M6 substrates, and electrolytic tricky gold end for trusted eight-layer, 3–five cm² https://thebookmarkfree.com/story21778063/choice-standards-for-high-density-hdi-pcb-boards-in-optical-communication