Out in Front: May 23, 1996
The use of copper electrodes, rather than traditional palladium-silver alloys, results in a drastic reduction in equivalent series resistance (ESR) in a family of multilayer capacitors from AVX. The first formulation to use the new process is NP0 (negative-positive zero), or C0G, a low-dielectric-constant material that offers a ±30- ppm/8C maximum temperature coefficient.Measured data for ESR vs frequency yields the curves in Figure 1. The significantly lower ESR of the copper-based capacitors makes them appropriate for microwave and RF applications. Moreover, the low cost of copper vs that of precious metals promises lower manufacturing costs when the new process reaches full production.
The NP0 capacitors are available in 0805 and 0603 standard chip sizes and are rated at 50V. All EIA-standard values—to 100 pF in the 0805 size and to 47 pF in the 0603 size—are available. Typical price is $0.20 (100,000).
—by Bill Travis
AVX Ceramics, Myrtle Beach, SC. (803) 946-0484.