Michael Casper, president and CEO of UltraSource Inc., a thin film ceramic microchip manufacturer is pleased to announce that they have developed a high density (HD) thin film based ENEPIG process that now combines low cost sputtering, traditional thin film photolithography and etching, and plating with ENEPIG. 

In order to improve reliability of RoHS compatible solder joints, the PCB industry has been exploring new metal finishes for the final finish on Copper PCB metalization. One new finish, known as “ENEPIG”, is a highly engineered film that is compatible with both Gold and Aluminum wirebonding and eliminates the SAC solder joint strength and reliability issues related to Gold embrittlement. This finish is applied to the entire circuit after thin film sputtering and patterning, offering the ultimate flexibility in assembly techniques while maintaining quality and reliability of a traditional thin film.

ENEPIG, acronym for Electroless Nickel (EN) Electroless Palladium (EP) Immersion Gold (IG), is defined in IPC-4556*, and has been adopted as a standard plating scheme for applications including soldering, wirebonding and as a contact finish. *Note:  IPC is the Institute of Interconnection and Packaging Electronic Circuits.

Casper explains that “this process is well suited to volume applications and is less expensive than traditional thin film choices because the ENEPIG finish is plated and contains very small amounts of precious metals.”

In the ENEPIG metalization scheme, the Palladium inhibits Nickel diffusion into the Gold layer, promoting long term shelf life (before assembly) benefits. During SAC soldering, the Eelctroless Palladium provides excellent solderability and can withstand multiple rework cycles. The solder strength of SAC solders to ENEPIG is very high. Both Gold and Aluminum wire bonding can be performed on ENEPIG.

Contact UltraSource for further information to discuss your specific applications needs or to discuss how ENEPIG can help your new application.