FR4 epoxy fiberglass laminates have also been used but the Duroid laminates, polyimides, Teflons, and ceramic substrates typically have better electrical impedance, thermal, chemical, and mechanical properties than FR4 laminates. Antennas have been designed and built on substrate thicknesses from 5 thousandths to 60 thousandths (.127 MM to 1.52 MM) typically, with some antenna designers requesting thicknesses up to .250 inches (6.35 millimeters). These substrates are copper clad, single or double sided, with 1/4 oz., 1/2 oz., 1 oz., and 2 oz. copper typical. Double-sided substrates are typically used for microstrip antenna ground planes.
Once the photo etch process is completed, the etched antenna elements can then be electroplated with various metals or alloys such as tin nickel or gold plating. The plating process depends on the customer’s applications and antenna design requirements.
Flex Film Antennas
Flex-film polyimides, Kapton, and other polyimide flex substrates have also been used for a variety of photo etched antennas. E-FAB has built antennas using flex-films with thickness as thin as .001 inches (25 microns). See more information on E-FAB flex circuits.
Photo Etch vs. Printed Circuit Board Etching
The advantage of using E-FAB’s photo etch process compared to PCB manufacturers, is E-FAB can hold tighter tolerances than traditional printed circuit board shops. With E-FAB’s photo etch solution, we can etch a wide variety of metals and alloys. Circuit board shops are typically limited to the types of metals and substrates they will work with because of the PCB shops limited chemical etching solutions on hand. In fact, many PCB shops actually use E-FAB to build the parts for their customers when the design requirements dictate processes beyond that of the PCB shops’ abilities.
Antenna Fabrication Experience With E-FAB
Experience is another factor to consider when having reliable antennas manufactured. Most circuit board manufacturers have experience with FR4 but have very little if any experience at all when dealing with microstrip etched antennas. E-FAB has been building antennas since 1981 and is a preferred supplier for many industry leaders. E-FAB has built antennas for JPL, NASA, the military, and private sector companies and has antenna manufacturing experience with: cones, horns, helix, spirals, microstrips, patch, hybrid etched antenna arrays, phase array, fractals, micro, blade, miniature parabolics, rigid and flexible antennas.