Radio frequency IC tag and method for manufacturing the same

• US 20050275539A1
• Filed: 02/09/2005
• Published: 12/15/2005
• Est. Priority Date: 06/11/2004
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Sakama, Isao, Ashizawa, Minoru
• Granted Patent: US 7,405,664 B2
• Time in Patent Office: Days
• US Class Current: 340/572.700
• CPC Class Codes: G06K 19/07756 the connection being non-galvanic, e.g. capacitive
• CPC Class Codes: G06K 19/07786 the antenna being of the HF type, such as a dipole
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 19/00 Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic combination of horns with slotted waveguide array H01Q13/0233
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407
• CPC Class Codes: Y10T 156/1052 with cutting, punching, tearing or severing
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49156 with selective destruction of conductive paths

Abstract

A radio frequency IC tag and a manufacturing method for the same includes an IC chip on which information is stored, and an antenna for transmitting the information that is stored on the IC chip. In the antenna, a power-feeding part on which the IC chip is mounted extends along a direction in which an electric current flows. Radiation parts are formed so that the width of the radiation parts becomes wider than that of the power-feeding part with respect to the longitudinal axis of the power-feeding part. The radiation parts extend from the power-feeding part, at both sides thereof, along the direction in which the electric current flows.

Claims

1. A radio frequency IC tag comprising:

an IC chip having information stored thereon for transmission; and

an antenna serving to radiate by electromagnetic transmission the information that is stored on the IC chip;

wherein;

in said antenna, a power-feeding part equipped with the IC chip has a longitudinal axis along a direction in which an electric current flows, and radiation parts are formed so that a width of said radiation parts becomes wider than that of the power-feeding part with respect to the longitudinal axis of the power-feeding part, said radiation parts extending from the power-feeding part at both sides thereof along the direction in which the electric current flows.

2. A radio frequency IC tag according to claim 1, wherein said antenna has an H shape defined by the power-feeding part and the radiation parts.

3. A radio frequency IC tag according to claim 1, wherein:

in said antenna, each of the radiation parts extending from both sides of the power-feeding part is formed in a semicircular shape, and the power-feeding part and the radiation parts together form a circular shape.

4. A radio frequency IC tag according to claim 1, wherein:

an insulation material is provided between the power-feeding part and the radiation parts, and the power-feeding part and the radiation parts are coupled each other by means of electrostatic capacitive coupling.

5. A radio frequency IC tag according to claim 1, wherein said power-feeding part is provided at a position where the radiation parts are symmetric in the up and down direction and also in the right and left direction.

6. A radio frequency IC tag according to claim 1, wherein said power-feeding part is provided at a position where the radiation parts become asymmetric at least either in the up-and-down direction or in the right-and-left direction.

7. A radio frequency IC tag according to claim 5, wherein at least one radiation part is provided with at least one opening at an arbitrary position thereof.

8. A radio frequency IC tag according to claim 6, wherein at least one radiation part is provided with openings different in shape at arbitrary positions thereof.

9. A radio frequency IC tag according to claim 8, wherein the openings are a circle or a polygon in shape.

10. A radio frequency IC tag according to claim 9, wherein the power-feeding part is positioned in association with a position of one or more openings with which at least one of the radiation parts is provided.

11. A radio frequency IC tag according to claim 5, wherein at least one radiation part is provided with at least one notch at an arbitrary position on the outer periphery thereof.

12. A radio frequency IC tag according to claim 5, wherein at least one radiation part is provided with notches different in shape at arbitrary positions on the outer periphery thereof.

13. A radio frequency IC tag according to claim 11, wherein the at least one notch is a circle or a polygon in shape.

14. A radio frequency IC tag according to claim 11, wherein the power-feeding part is positioned in association with the position of the at least one notch with which the radiation part is provided on the outer circumference thereof.

15. A radio frequency IC tag according to claim 6, wherein:

at least one radiation part is provided with at least one opening at an arbitrary position thereof, and at least one radiation part is provided with at least one notch at an arbitrary position on the circumference thereof.

16. A radio frequency IC tag according to claim 15, wherein the opening has the same shape as that of the notch.

17. A radio frequency IC tag according to claim 15, wherein the opening has a shape different from that of the notch.

18. A manufacturing method for manufacturing a radio frequency IC tag, said radio frequency IC tag comprising an IC chip on which information is stored, and an antenna for transmitting the information that is stored to the IC chip, said manufacturing method comprising the steps of:

forming an antenna on a surface of an insulative substrate by subjecting a conductor to patterning to provide a power-feeding part, and subjecting radiation parts to patterning with the conductor so that a width of said radiation parts becomes wider than a width of the power-feeding part with respect to the longitudinal axis of the power-feeding part, said radiation parts extending from the power-feeding part at both sides thereof along the direction in which the electric current flows;

mounting an IC chip on the power-feeding part, and electrically connecting the IC chip to the conductor; and

coating, with an isolation cover, the IC chip and the conductor that forms the power-feeding part and the radiation parts.

19. A manufacturing method for manufacturing a radio frequency IC tag according to claim 18, further comprising the step of:

forming a slit in a part of the antenna on which said IC chip is mounted, wherein said IC chip is connected across the slit.

20. A manufacturing method for manufacturing a radio frequency IC tag, said radio frequency IC tag comprising an IC chip having stored information, and an antenna for transmitting the stored information, said manufacturing method comprising the steps of:

subjecting a conductor to patterning to form an antenna on a surface of an insulative substrate to act as a power-feeding part;

mounting the IC chip on the power-feeding part of the antenna, and electrically connecting the IC chip to the antenna;

coating an insulation material on a surface of the antenna;

locating, adjacent to the power feeding part, with the IC chip located therebetween, a first auxiliary antenna and a second auxiliary antenna having a width greater than a width of the power feeding part; and

coating, with an isolation cover, the first auxiliary antenna, the second auxiliary antenna, and the power-feeding part having the IC chip.