Laser Drilled Materials
The most cost-effective path for the fabrication of densely populated circuit boards is the design of multi-depth blind microvias in-pad technology. It has been proven for some time now that blind microvias within SMD Pads can substantially reduce the number of layers for a dense circuit board design and in addition allow for denser component placement.
Arlon’s 85NT polyimide resin and 55NT multifunctional epoxy resin system on non-woven aramid reinforcement provides excellent via quality, speed of laser processing, and exceptional dimensional stability for alignment of stacked microvias.
85NT is a pure polyimide laminate and prepreg system with a glass transition temperature of 250°C, with a non-woven aramid reinforcement. 85NT combines the high-reliability features of polyimide, improved PTH reliability and temperature stability with the low in-plane (X,Y) expansion of 7-9 ppm/°C and outstanding dimensional stability of the aramid reinforcement. 85NT meets the requirements of IPC-4101E/53.
55NT is a multifunctional epoxy resin laminate and prepreg system, with a Non-woven aramid reinforcement. This system combines compatibility with leadfree processing, using a high glass transition temperature multifunctional epoxy resin of 170°C with the low in-plane (X,Y) expansion of 6-9 ppm/°C and outstanding dimensional stability of non-woven aramid reinforcement. 55NT meets the requirements of IPC 4101E/55.
Another option is the 85HP laminate and prepreg system. This material utilizes square and spread glass fabric reinforcements to minimize high glass densities and resin rich areas to provide more uniform via quality. The ceramic filler in the resin contributes to making the composite more homogeneous as seen by the laser beam.
Arlon 85HP’s unique blend of pure polyimide resin and micro-fine proprietary fillers results in superior performance for demanding applications. Compared to conventional polyimide systems, 85HP has a lower Z-axis expansion and twice the thermal conductivity. 85HP reduces resin cracking and wicking in designs with high density plated through holes and vias. 85HP prepreg has resin flow characteristics and pressed thickness matching standard polyimides. 85HP meets the requirements of IPC-4101E/40, /41 and /43.