Managing Intellectual Property Rights in Semi Custom Module Engineering
Module IP management requires defining baseline assets, acquiring raw CAD and containerized build packages, and securing clear derivative assignment.
Microvias
Meaning
High density interconnection involves laser drilled channels known as microvias that pass through dielectric layers to connect adjacent or nonadjacent conductive planes in multilayer printed circuit boards. These miniature holes typically feature diameters below one hundred and fifty micrometres and must be filled with copper or conductive paste during sequential lamination cycles. The specification applies strictly to subsurface signal routing within high frequency boards and excludes traditional through hole plated barrels that traverse the entire thickness of the panel.
Laser Drilling
Ultraviolet and carbon dioxide laser sources ablate resin and glass fiber bundles to form blind or buried geometries without mechanical drill breakage. Beam energy density requires strict adjustment to prevent excessive inner layer copper damage while achieving proper wall taper angles for subsequent plating adhesion. Optical alignment systems verify target registration prior to firing pulses, ensuring that positional variance remains within tight tolerances specified by fabrication drawings.
Copper Plating
Acid copper electroplating baths deposit metal uniformly inside small diameter apertures without forming interior voids or surface depressions. Additive chemistry formulation controls throwing power to build sufficient thickness along barrel walls while minimizing overhang at the outer annular ring. Current density adjustments and periodic pulse reverse waveforms prevent premature sealing at the aperture mouth before complete vertical fill occurs.
Thermal Reliability
Interconnect endurance depends on matching the coefficient of thermal expansion between the cured resin and the deposited barrel metal during reflow soldering cycles. Z axis expansion stresses joints repeatedly, leading to barrel cracking or pad separation if resin cure is incomplete or plating elongation is insufficient. Destructive physical analysis on microsectioned coupons confirms that successful assemblies withstand thermal shock testing without exhibiting interfacial delamination or barrel fatigue.