General Information

PCL-CF-400 is a high glass transition temperature (Tg), FR-4 epoxy resin coated foil designed for microvia and high-density applications. The epoxy resin is based on the same system used in Polyclad's high performance 370 laminates and prepregs. It consists of electro-deposited copper foil coated with two layers of epoxy resin. The first resin layer adjacent to the copper foil is a fully cured, C-stage layer providing consistent dielectric thickness control. The second resin layer is a B-staged layer, manufactured to precise rheological properties to provide optimal flow and fill during the lamination process. PCL-CF-400 is compatible with all Polyclad FR-4 laminate and prepreg grades. Because the resin is based on the 370 system of laminate and prepregs, processability and performance are consistent with other Polyclad FR-4 systems with the exception of a lower dielectric constant because there is no woven glass reinforcement. The 400 system is also laser fluorescing and UV blocking for maximum compatibility with automated optical inspection systems (AOI), optical positioning systems and photoimagable soldermask imaging.

AVAILABLITY
PCL-CF-400 resin coated foils are available with a variety of copper foil weights and thicknesses. 5 micron (1/8 ounce) with a copper carrier, 12-micron (3/8 ounce) and 18 micron (1/2 ounce) unsupported are standard copper thicknesses. High temperature elongation (HTE), low profile copper foils are standard. PCL-CF-400 with other copper foil types and thicknesses can be custom made to meet specific requirements. Standard total resin thickness from 50 microns to 100 microns are available. Other thicknesses may be available for specific applications.

PROCESSING AND STORAGE
Storage of PCL-CF-400 resin coated foils is the same as for FR-4 prepregs. TURBO Resin Coated Foils should be stored at 65±3° F (18±2°C) and 30-50% relative humidity. Temperatures and humidity above recommended conditions should be avoided during shipment and transport. Resin coated foils stored below recommended temperatures should be allowed to equilibrate to the above specified conditions for a minimum of eight hours prior to use. A variety of inner layer copper bonding treatments, including oxides, oxide alternative and double-treat coppers, can be used successfully with Polyclad materials. Polyclad does not recommend the use of Tin based innerlayer bonding treatments. More detailed storage recommendation technical bulletins are available from Polyclad.

APPLICABLE SPECIFICATIONS AND RECOGNITIONS
Polyclad's UL file number is E45456. PCL-CF-400 is UL listed under the generic designation PCL-CF-400. PCL-CF-400 resin coated foil and PWBs constructed using it are capable of achieving a UL 94-V0 flammability rating and the highest UL maximum continuous operating temperature for FR-4 grades of 130°C. Ratings for all Polyclad FR-4 laminate and prepreg grades under the generic PCL-FR- (a)(a) laminate and PCL-FRP- (a)(a) prepreg recognitions are interchangeable from a UL listing standpoint and are therefore interchangeable for use with PCL-CF-400. Certain other more specific parts of Polyclad's UL listing may be applicable in some cases. PCL-CF-400 can be certified to IPC/JPCA-4104, Specification for High Density Interconnect (HDI) and Microvia Materials, specification sheet IPC/JPCA-4104/12, Designation CI C 1 N 1 CF 1 Epoxy Coated Foil, and IPC-CF-148A, Resin Coated Foil for Printed Boards, specification sheet IPC-CF-148A/02. Other industry or customer specific specifications, recognitions or designations may be applicable or certifiable to in certain cases. If you need additional information or have questions, please contact Polyclad Technical Services.