RFID integrated circuits with electrical bridges

A method of forming a Radio-Frequency Identification (RFID) tag structure including an RFID integrated circuit (IC) and a two-turn planar antenna loop, the method comprising:

• providing the RFID IC, the IC comprising:
• a semiconductor substrate including circuitry;
• a nonconductive repassivation layer disposed on the substrate and over the circuitry, wherein the nonconductive repassivation layer is confined within a perimeter of and forms a substantial portion of a surface of the substrate;
• a first contact pad:
• at least partly disposed on the nonconductive repassivation layer,
• confined within the perimeter of the surface,
• disposed near a periphery of the surface, and
• configured to couple the circuitry to an antenna terminal;
• a second contact pad:
• at least partly disposed on the nonconductive repassivation layer,
• confined within the perimeter of the surface,
• disposed near a periphery of the surface diametrically opposite the first contact pad, and
• configured to couple the circuitry to another antenna terminal;
• and
• a conductive bridge:
• disposed between the first and second contact pads,
• substantially spanning a diameter of the surface,
• disposed substantially on the nonconductive repassivation layer, and
• electrically isolated from the first contact pad, the second contact pad, and the circuitry;
• providing first and second concentric loops of the two-turn antenna loop, wherein:
• the first loop has a first discontinuity forming the first antenna terminal and a third antenna terminal;
• the second loop has a second discontinuity forming the second antenna terminal and a fourth antenna terminal;
• and
• the first and second discontinuities are at substantially the same azimuth;
• and
• attaching the IC to the first and second concentric loops such that the first contact pad connects to the first antenna terminal, the second contact pad connects to the second antenna terminal, and the bridge electrically couples the third and fourth antenna terminals together and forms a multi-loop antenna from the two-turn antenna loop.

A method of forming a Radio-Frequency Identification (RFID) tag including an RFID integrated circuit (IC), and a two-turn planar antenna loop, and a radiating antenna structure, the method comprising:

• providing the RFID IC, the IC comprising:
• a semiconductor substrate including circuitry;
• a nonconductive repassivation layer disposed on the substrate and over the circuitry, wherein the nonconductive repassivation layer is confined within a perimeter of and forms a substantial portion of a surface of the substrate;
• a first contact pad:
• at least partly disposed on the nonconductive repassivation layer,
• confined within the perimeter of the surface,
• disposed near a periphery of the surface, and
• configured to couple the circuitry to an antenna terminal;
• a second contact pad:
• at least partly disposed on the nonconductive repassivation layer,
• confined within the perimeter of the surface,
• disposed near a periphery of the surface diametrically opposite the first contact pad, and
• configured to couple the circuitry to another antenna terminal;
• and
• a conductive bridge:
• disposed between the first and second contact pads,
• substantially spanning a diameter of the surface,
• disposed substantially on the nonconductive repassivation layer, and
• electrically isolated from the first contact pad, the second contact pad, and the circuitry;
• providing first and second concentric loops of the two-turn antenna loop, wherein:
• the first loop has a first discontinuity forming the first antenna terminal and a third antenna terminal;
• the second loop has a second discontinuity forming the second antenna terminal and a fourth antenna terminal;
• and
• the first and second discontinuities are at substantially the same azimuth;
• and
• attaching the IC to the first and second concentric loops such that the first contact pad connects to the first antenna terminal, the second contact pad connects to the second antenna terminal, and the bridge electrically couples the third and fourth antenna terminals together, thereby forming an antenna segment;
• and
• coupling the antenna segment to the radiating antenna structure.