Remtec has developed a proprietary process for manufacturing cost-effective ceramic circuits metalized with nickel-gold plated silver thick films. These metalized ceramic substrates are an economical substitute for currently used thick film materials containing platinum-palladium. They also are RoHS-compliant.
The Low Cost Metalized Ceramic (LCMC) substrates are manufactured by a proprietary process that combines thick film processing with Ni-Au plating. The new LCMC substrates also offer a number of significant performance advantages.
The key advantage of the new LCMC circuits is the significant reduction of solder leaching typical of conventional thick film substrates. Solder leaching is especially damaging when using lead free soldering processed at temperatures of 260°C or higher. The LCMC substrates assure more reliable solder connections required for RoHS compliance and can withstand multiple SMT reflow solder cycles and repairs without any noticeable solder leaching.
The tracks resistivity of these substrates (1 mΩ/square to 2 mΩ/square) is improved and the substrates can be used in thermally demanding applications up to 170°C continuous operation temperature. Pattern definition can be held to 0.004-in. lines and spaces. The ceramic panels can also be fabricated in a 5-in. × 7-in. format.
By combining various thick-film metals and selective gold plating techniques, different types of surface finish area achieved. Therefore, the same metalized ceramic substrate yields a 2 micro-inch to 4 micro-inch gold finish for SMT soldering and welding, a 30 micro-inch to 50 micro-inch gold finish, which is excellent for gold wire bonding and a 100 micro-inch of gold for brazing and eutectic die attach.
All the features of Remtec’s plated copper on thick-film technology, such as integrated resistors and plugged via holes, also are available with the new LCMC products. For pricing and availability, contact Remtec.