RFID tag and manufacturing method thereof

• US 8,299,925 B2
• Filed: 07/25/2008
• Issued: 10/30/2012
• Est. Priority Date: 10/26/2007
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Kobayashi, Hiroshi, Kobae, Kenji
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): MORTELL, JOHN F
• Application Number:
  US12/180,117
• Publication Number:
  US 20090109000A1
• Time in Patent Office: 1,558 Days
• Field of Search: 340/572.8
• US Class Current: 340/572.1
• CPC Class Codes: G06K 19/072 the record carrier comprising a plurality of integrated circuit chips
• CPC Class Codes: G06K 19/07745 Mounting details of integrated circuit chips
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/0775 arrangements for connecting the integrated circuit to the antenna
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 24/81 using a bump connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: Y10T 29/49018 with other electrical component
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base

Abstract

The RFID tag has a base sheet having a recess, a first element provided on the base sheet astride the recess, a second element which is provided between the first element and the base sheet and which is electrically connected to the first element, and a communication antenna which is provided on the base sheet and which is connected to at least any of the first element and the second element.

Claims

1. A manufacturing method of an RFID tag comprising:

forming a conductive pattern and a communication antenna on a surface of a heat-softening base sheet;

mounting a second semiconductor element on the conductive pattern, with a thermosetting adhesive sandwiched therebetween;

heating the heat-softening base sheet mounted with the second semiconductor element, to harden the thermosetting adhesive and to form, by the heating to harden the thermosetting adhesive, a recess having a greater dimension than the second semiconductor element in a portion of the base sheet where the second semiconductor element is mounted;

mounting a first semiconductor element having a greater dimension than the recess astride the recess of the base sheet;

connecting the first semiconductor element to the conductive pattern; and

connecting at least any of the first semiconductor element and the second semiconductor element to the communication antenna on the base sheet.

2. The manufacturing method of the RFID tag according to claim 1, wherein a plurality of bumps of the first semiconductor element are located outside the recess.