Circuits Assembly Online Magazine - Current Issue

Products

Photo Stencil announces the results of Universal SMT Laboratories’ independent, extensive study, conducted in February 2006. The print-process study isolated the stencil alone to determine performance differences among a group of stencils manufactured by other stencil suppliers. Photo Stencil’s AMTX E-FABstencil performed the best out of 12 stencils tested, provided by five different stencil manufacturers. The Xerox-authorized stencil manufacturer usse the AMTX Electroform stencil technology, licensed under U. S. Patents owned by Xerox and acquired by Photo Stencil in 1998.

The study included five electroform stencils and seven laser stencils, including Photo Stencil’s proprietary NicAlloy stencil. The report contains extensive data on the solder volume data for a range of SMT devices and aperture designs. Solder paste deposit heights, area and volume were measured for over 154,000 solder paste bricks. Solder paste volume and paste volume repeatability were measured for 16 SMT components in all 12 stencils. Both Pb-free and SnPb solder paste were used in the study. Stencils were ranked in paste volume delivery performance as well as paste volume repeatability. Photo Stencil’s E-FAB stencil provided the best paste transfer for both solder pastes among all stencils tested. NicAlloy was in second place for paste transfer.

The yield analysis program was used to determine the yield loss due to open defects of BGA and microBGA packages directly attributed to the stencil. The results show that compared to the best stencil, the increase in repair costs vary from an additional $658 for the second best to an additional $10,122 for the last place stencil. E-FAB provided the lowest rework cost for both solder pastes among all 12 stencils tested, with NicAlloy again coming in second.

For a copy of the full report, contact Dr. Coleman at 719-535-8528 or bcoleman@photostencil.com.

BEST Inc. has developed a simpler process for reworking or hand-placing high lead count connectors. The StencilQuik polyimide stay-in-place stencil helps rework high-density connectors by preventing bridging of neighboring solder joints while allowing technicians to “fit” connector contacts into the stencil.

The process of placing or reworking the connector has been simplified. After preparing the site, the stencil is peeled from its release liner. It is then aligned on the circuit board. Solder paste is then squeegeed into the apertures of the stencil with the remaining material wiped away with a lint-free cloth. The connector is “fitted” into the loaded apertures and then reflowed. Any mask damage ensuing from device removal is repaired by placing the device onto the board.

“Repair depots and rework operations of electronic assemblers are raving about the time that they save and the quality of the rework using StencilQuik™ on hard to rework 50 plus pin connectors. In addition, hardware developers like the fact that to can easily place the more complex connectors on their development board on their own.” said Bob Wettermann of BEST Inc.

Available in both 4 and 8 mil (0.10 to 0.20 mm) thickness. The stay-in-place feature means no compromising in solder paste volume. Each stencil is custom engineered to the application at hand. Deliveries are five business days with 24 to 48 hr. expedites available.

Business Electronics Soldering Technologies (BEST), www.solder.net

ENDICOTT, NY— Endicott Interconnect Technologies has been awarded several new contracts for fabrication of wire bond PBGA substrates resulting from alliances with Silicon Valley-based companies Singulated Technology and CORWIL Technology Corp.

EI will provide wire bond PBGA substrates per Singulated Technology’s design specifications and CORWIL will provide the module assembly. End customers for these semiconductor modules use them in military, commercial and wireless electronics applications.

“This unique approach aligns best-in-class suppliers of substrate design, fabrication and assembly to produce superior finished products for low to mid volume applications where time-to-market is a critical factor in winning the business,” said James J. McNamara Jr., president and CEO of EI. “The EI team is very excited about the opportunity to partner with industry innovators, Singulated and CORWIL, and to provide substrates that add differentiating value.”