This invention discloses the application of NBF (NBF film) on circuit boards, the circuit board itself, and its manufacturing method. It utilizes a
silicone-free, fiberglass-free integrated NBF film to replace traditional PP prepreg, leveraging its high
adhesive flow properties to achieve void-free, full filling of
copper thicknesses exceeding 30μm and fine-
pitch trenches within 20μm. The circuit board employs a differentiated stacking structure of a central rigid BT substrate and an outer ultra-thin
dielectric material layer, incorporating dummy
copper lines and trenches to effectively balance
copper density, offset
internal stress during stacking, reduce
dielectric thickness variation, and suppress board warping. This invention is complemented by rolling pre-attachment, bidirectional pressure application, and copper surface
browning processes, effectively improving interlayer
adhesion strength and board
surface flatness, controlling
dielectric thickness variation within 3.1μm. This invention solves the problems of voids, insufficient
adhesive, uneven thickness, easy deformation, and poor reliability inherent in traditional products, enabling stable
mass production of high-layer-count, ultra-thin, and highly reliable thick copper circuit boards.