Modern electronic designs are becoming more and more slim and portable. The use of more complex components with very high Input /Output (I/O) count have pushed PCB fabricators to evolve to use new techniques for creating smaller vias and have also pushed them to develop new processes, or re-tool old ones. These processes include revised methods of producing holes from the conventional drill, to processes such as laser drilling. Reduction of the via hole size will allow the designer to significantly increase the routing density through the use of vias in  surface-mount technology(SMT pads), which will in-turn minimize the size and weight of the product to improve the electrical performance of  the system. These types of boards are generically called High-Density Interconnects(HDI).

Multilayer technology allows the designer to sequentially add additional pairs of layers to form a multilayer core. For designs with a dielectric element which has copper foil both on the top and bottom we use our laser drill machine to produce holes on the inner layers which then go on to the imaging and etching process. This added approach for HDI design typically is called the Sequential Build-up (SBU) .

SBU printed circuit boards are commonly described as 1+N+1,2+N+2..etc.Where N is the number of layers that constitutes the formed inner core. One and two, etc. are the number of added layers. At Imagineering we can currently produce boards that are 4+N+4.

Fabricating with solid metal vias is our method of metallization on Interconnect Via holes(IVHs). It not only provides the stacked vias a stronger interconnection but also helps in obtaining better thermal management as well, which in-turn significantly increases the board reliability under severe operational circumstances.