Silver Flex Circuits
Silver flex membrane switches represent the most popular electronic interface solutions due to their affordability. Thin
flexible layers preserve a low profile without compromising versatility in design options.
Conductive silver inks are screen printed directly onto a flexible film substrate. This process is more cost-effective than the chemically etched copper, and poses less potential threat to the environment.
Silver flex switches are considered the most popular for custom membrane switches and keypads.
In its simplest form, a flexible circuit is a vast cumulation of conductors bonded to a thin dielectric, or insulating, film.
Silver or copper may be used as an electric conductor. Silver Flex Circuits are a popular alternative to Copper Flex Circuits. Silver ink conductors are added to the flexible film substrate using a screen-printing process, making it the more popular and cost-effective choice. In a Copper Flex Circuit, a very thin sheet of copper is first laminated to the flexible film substrate then chemically etched away, leaving copper traces. The etching process is not as environmentally friendly and more expensive than screen-printing silver traces.
Silver flex circuit options include:
- Single-sided
- Double-sided (thru-hole)
- Heat stabilized polyester
- Embedded SMD (LEDs)
- Carbon overcoat
- Printed resistors
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Comparison Chart |
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Characteristic |
Silver Ink |
Copper |
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Printing vs. Etching |
Conductive silver ink traces are screen printed onto the film substrate. |
Copper is chemically etched away, leaving conductive traces. More expensive than screen-printing. |
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Pliability/Weight |
Silver traces are lightweight and more flexible than solid copper traces. |
Solid copper traces are heavier and more durable than softer printed silver traces. |
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Conductivity |
Resistivity approx 50 mOhms/sq |
Lower electrical resistance and higher conductivity. |
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Price |
Low to Moderate |
Expensive to very expensive |
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Soldering |
No. Components are attached with conductive adhesive. |
Ability to solder active and passive components into the switch design. |
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Pitch |
Minimum of 1.00mm. |
Possible pitch 0.5mm and 0.3mm for ZIF connector |