Lucent Technologies Venture Announces Electroplating Process That Gets the Lead Out of Solder Materials.

MURRAY HILL, N.J.--(BUSINESS WIRE)--April 28, 1999--

New Process Provides Unmatched Reliability And Stability For

Electronic Parts

Electroplating Chemicals & Services, a wholly owned venture of Lucent Technologies (NYSE: LU), has developed a new electroplating process for creating a special form of pure tin that can be used in lead-free soldering applications.

The lead-free process is called SnTech (pronounced "tin tech"), from the chemical symbol for tin, Sn. The patented process is easy to implement in electronics manufacturing and results in a coating that overcomes the traditional shortcomings of tin/lead solder alloys or pure tin.

Until now, the electronics industry was reluctant to use pure tin as a solder material or a final finish because as the tin aged, its small grain structure (about 0.1 microns, or about four ten-thousandths of an inch) would crystallize in response to internal stresses. These tiny tin single crystals, called "whiskers," could cause short circuits. SnTech products, sold in the form of water soluble salts used for electrochemical deposition, produce a tin coating with a relatively large grain structure (about 5 microns, or two hundredths of an inch), which inhibits whisker formation.

The SnTech products use a set of organic chemicals that are specially formulated so they are not incorporated in the resulting electroplated tin coating. In general, lower amounts of organic impurities in a solderable coating result in better physical stability of the material. Compared to the lead-free SnTech product, conventional tin/lead compositions contain high levels of organic impurities.

"Virtually all electronics products currently contain electroplated tin-lead solder. The U.S. electronics industry electroplates 10,000 metric tons of tin-lead each year," said Joe Abys, president of Electroplating Chemicals & Services.

Because the use of lead is not good for the environment, the SNTech product will help companies who want to sell electronics products in markets that increasingly are promoting the use of lead-free products. Some of these initiatives could eventually have the effect of restricting the importation of U.S. manufactured products. "Our objective", said Joe Abys, "is to develop environmentally benign products that can help U.S. electronics manufacturers meet these challenges."

"Like the ancient alchemists, we can't change lead to gold; but if our process helps get the lead out of electronics factories, I think we'll make a valuable environmental contribution," said Yun Zhang, the Bell Labs scientist who invented the new process.

The SnTech process produces a smooth, satin-bright tin deposit with excellent ductility -- the ability to extend the coating over a larger metal surface. Ductility is also a measure of how well the alloy maintains its integrity even after it is bent.

The new process also results in a material with superior solderability -- the ability to bond with two solderable materials. Finally, the lead-free electrodeposit has outstanding reflowability -- the ability to melt onto another material and maintain structural integrity after cooling.

Through their industry road-mapping efforts, the National Electronics Manufacturing Initiative (NEMI) has identified the reduction and/or elimination of materials of concern as one of the areas that electronics companies should focus on in the next few years. "We are working with industry to encourage the development and deployment of no-lead solder interconnect systems. Since soldering is such a critical part of the manufacturing process, there can be significant impact on packaging contact finishes, printed wiring board (PWB) finishes, assembly equipment, processes and materials" said Jim McElroy the executive director and CEO of NEMI. "We believe that the development of processes such as SnTech could be a significant step towards lead-free electronic products".

SnTech could have a major impact on the production and application of solder alloys. This tin electroplating process is particularly suited for reel-to-reel electronic parts assembly operations. It also works well with rack-and-barrel processes. SnTech has been used in plating coatings for connectors, solder bumps, PWB's, and components for semiconductor applications.

Lucent Technologies Power Systems, a leading supplier of power supplies and power systems, is using SnTech in its SMC/SMW-series DC-to-DC converter power modules. Fairchild Semiconductor and International Rectifier are both testing SnTech for use in semiconductor and transistor products.

EC&S (www.lucent.com/ecs) is the world's leading supplier of palladium plating products. Additional product lines include plating processes using gold and gold alloys, tin and tin alloys, nickel, and rhodium; as well as the PallaTech MLS system for semiconductor packaging applications.

The EC&S team includes developmental scientists, technical service engineers, and technical field representatives with experience in electrochemistry, analytical chemistry, chemical engineering and electroplating. The venture business has a worldwide distribution network, with representatives in Japan, Singapore, Korea, Hong Kong, Taiwan, the United Kingdom, India, France and Canada.

Lucent Technologies, headquartered in Murray Hill, N. J., designs, builds and delivers a wide range of public and private networks, communications systems and software, data networking systems, business telephone systems and microelectronic components. Bell Labs is the research and development arm for the company. For more information on Lucent Technologies, visit the web site at www.lucent.com

Editor's note: To obtain a color or B & W photo of the inventor, Yun Zhang, in her lab, with a display of the crystal structure of the new material, just call Rosemarie Amato at 908-582-4120.