How do companies manufacture the transponders?
It depends on the type of transponders to which you are referring. A passive ultrahigh-frequency (UHF) transponder contains a microchip made of silicon. Attached to the chip is an antenna that can be composed of copper, aluminum, silver ink or some other conductive material. The chip and antenna are mounted on a substrate, which can be paper, polyethylene terephthalate (PET) or some other type of plastic. This is usually inserted into a thermal transfer label.
Passive low-frequency (LF) and high-frequency (HF) transponders are similar, though the antenna is almost always etched copper for these types of tags. LF transponders are sometimes enclosed in a glass ampule that can be inserted under an animal’s skin. Active tags typically have a circuit board, a battery and an exterior plastic housing, in addition to the components of passive tags.
—Mark Roberti, Founder and Editor, RFID Journal
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