Microwave Journal
www.microwavejournal.com/articles/2799-materials

MATERIALS

November 1, 1999

Materials

Chip Scale Package
The CSP family chip scale package with stacked die feature is available in a variety of body sizes and ball arrays (0.8 mm pitch), enabling adaptability to creative IC combinations in memory or logic configuration. The CSP package's small footprint allows OEM designers and engineers to integrate greater levels of functionality and features for shrinking communications and consumer electronics. The CSP package is most suited for shrinking products requiring a dense footprint for high performance applications. A family of CSP packages with input/output configurations ranging from 8 to 156 and respective substrates (packaging outline) sizes ranging from 4 mm x 4 mm to 13 mm x 13 mm in 1 mm increments is available.
Abpac Inc., 
Phoenix, AZ 
(602) 431-1200.

Fabric Gaskets
The Thermshield™ fabric gaskets are a low compression force material offering very high shielding results up to 105 dB at 10 MHz while providing environmental protection up to IP53. The gaskets become self-terminating when cut and reduce the risk of metal particles and sharp corners inherent in other types of gasket solutions. Several shapes and sizes are available including round, D-shaped, L-shaped and rectangular. The highly conductive fabric is available in nickel-copper, silver or tin-copper with a high strength adhesive.
Cambio International, 
Laconia, NH 
(603) 524-3714.

Photo-imageable Silver Conductor Composition
The new Fodel® photo-imageable silver conductor composition produces dense fired conductors on 951 Green Tape™conductors with smooth parallel edges on internal or surface layers. The conductor lines are patterned on the surface or unfired Green Tape using UV light and an aqueous development process. Offering a high conductivity, the composition is capable of patterning 50 mm lines and spaces on the internal or surface layers of complex interconnects. Photo-patterning of spiral inductors allows twice the number of spiral turns and twice the inductance in the same footprint as similar devices made using conventional screen printing, thus increasing the ability to integrate passive components within Green Tape multilayers.
DuPont Microcircuit, 
Wilmington, DE 
(800) 284-3382.

Gel Rope Gaskets
The dBseal™ gel rope gaskets utilize wire mesh impregnated with cured silicon gel to simultaneously provide EMI shielding, electrical grounding and environmental sealing in electronic and telecommunications equipment. The multifunctional gel rope gaskets provide a reliable, cost-effective alternative to two-piece rubber and metal mesh gaskets or one-piece metal-filled conductive elastomers for sealing and shielding designs. Shielding effectiveness is > 75 dB from 100 MHz to 1 GHz after salt spray testing. The gaskets effectively withstand exposure to hydraulic and cleaning fluids and lubricating oils and are well suited for use in electronic equipment exposed to moist environments and the threat of EMI. Six standard diameters ranging from 0.063" to 0.250" as well as custom diameters of up to 0.500" are available. Price: as low as 50¢ per foot, depending on size and volume. Delivery: two to four weeks (ARO).
Raychem Corp., Electronics OEM Components Division, 
Menlo Park, CA 
(800) 926-2425.