Thin radio frequency transponder with leadframe antenna structure

A radio frequency transponder comprising:

• a. a circuit chip having a surface, a radio frequency circuit, and one or more connectors electrically connected to the radio frequency circuit;
• b. a self-supporting leadframe antenna, said self-supporting leadframe antenna being an electrically conductive self-supporting foil of a material having a Young's Modulus on the order of 12.times.10.sup.11 dynes per square centimeter or greater, said self-supporting foil having no supporting substrate and having two or more ends, one or more of the ends being electrically attached to one of the connectors for the radio frequency circuit, the self-supporting foil itself forming an antenna for the radio frequency circuit, the leadframe having an off chip length and an overlapping length overlapping the surface, at least on of the ends being part of the overlapping length and being electrically and fixably attached to one of the connectors;
• and
• c. a protective coating covering the circuit chip surface and the ends overlapping the circuit chip surface.

A radio frequency circuit comprising:

• a. a circuit chip having a surface, a radio frequency circuit, and one or more connectors connected to the radio frequency circuit;
• b. a self-supporting leadframe antenna, said self-supporting leadframe antenna being an electrically conductive self-supporting foil of a material having a Young's Modulus on the order of 12.times.10.sup.11 dynes per square centimeter or greater, said self-supporting foil having no supporting substrate and having two or more ends, one or more of the ends being a connected end that is electrically and fixably attached to one of the connectors on the circuit chip, the self-supporting foil itself forming an antenna for the radio frequency circuit, the leadframe antenna having an off chip length and an overlapping length overlapping the surface, and at least one of the connected ends being part of the overlapping length;
• and
• c. a protective surrounding that envelops the circuit chip and the leadframe antenna.

A radio frequency transponder comprising:

• a. a circuit chip having a surface and a radio frequency circuit, and one or more connectors connected to the radio frequency circuit;
• b. a self-supporting leadframe antenna, said self-supporting leadframe antenna being an electrically conductive self-supporting foil of a material having a Young's Modulus on the order of 12.times.10.sup.11 dynes per square centimeter of greater, said self-supporting foil having no supporting substrate and having two or more ends, one or more of the ends being a connected end that is electrically and fixably attached to one of the connectors on the circuit chip, the self-supporting foil itself forming an antenna for the radio frequency circuit, the leadframe antenna having an off chip length and an overlapping length, the off chip length not overlapping the surface and the overlapping length overlapping the surface, at least one of the connected ends being part of the overlapping length;
• and
• c. a protective coating covering the connectors and at least a portion of the chip surface;
• and
• d. a protective surrounding that envelops the circuit chip, the protective coating, and the leadframe antenna.

A radio frequency transponder comprising:

• a. a circuit chip having a surface and one or more connectors on the circuit chip;
• b. a self-supporting leadframe antenna, said self-supporting leadframe antenna being an electrically conductive self-supporting foil of material having a Young's Modulus on the order of 12.times.10.sup.11 dynes per square centimeter or greater, said self-supporting foil having no supporting substrate and having two or more ends, one or more of the ends being a connected end that is electrically and fixably attached to one of the connectors on the circuit chip, the self-supporting foil itself forming an antenna for the radio frequency circuit, the leadframe antenna having an off chip length and an overlapping length, the off chip length not overlapping the surface and the overlapping length overlapping the surface, at least one of the connected ends being part of the overlapping length, the leadframe antenna being positioned by one or more positioners attached to the leadframe antenna at one or more locations along the off chip length;
• and
• c. a protective coating covering the connectors and at least a portion of the chip surface;
• and
• d. a protective surrounding that envelops the circuit chip, the protective coating, and the leadframe antenna.