AVX has developed tiny low-pass filters and directional couplers using a thin-film process it developed for capacitor-related problems that result from using larger, thick-film hybrids.
The low-pass filters, which incorporate five passive components, fit into an 0402 surface mount package. The size is normally reserved for single resistors or capacitors.
Mark Chapman, product marketing manager for microwave and thin-film at AVX, said: "Typically, people have gone for thick-film. AVX took the thin-film route to solve some problems with capacitors. When you get to frequencies above 450MHz, there are problems with multi-layer techniques."
But thick-film devices have typically been cheaper in the past. Chapman says the ability to make thin-film devices both smaller and cheaper came from a combination of better design tools and IC-style manufacturing techniques.
"It is chip making applied to passives. If you get the process right the costs come down," he said.
For the couplers, AVX has introduced inductors to the process, and the company has also developed a way of creating resistors on the alumina substrate using nichrome to help build splitters.
For design, the company uses Agilent Technologies' ADS Momentum RF design tools:
"Opening up this capability for thin-film comes from being able to model the parasitics," said Chapman. "We have taken the design cycle from weeks or months to a day."