Monolithic integrated circuit and antenna coil structure comprising a peripheral protective ring

• US 6,127,989 A
• Filed: 03/10/1998
• Issued: 10/03/2000
• Est. Priority Date: 03/24/1997
• Status: Expired due to Fees

• Current Assignee: EM Microelectronic - Marin SA (The Swatch Group AG)
• Original Assignee: EM Microelectronic - Marin SA (The Swatch Group AG)
• Inventors: Kunz, Pascal
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): VANNUCCI, JAMES
• Application Number:
  US09/037,715
• Time in Patent Office: 938 Days
• Field of Search: 235/449, 340/572, 343/700 MS, 343/895, 343/702, 343/732, 343/833, 343/837, 343/842, 343/867, 343/870, 343/878
• US Class Current: 343/895
• 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: 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 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• 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 7/04 Screened antennas H01Q7/02, H01Q7/06 take precedence

Abstract

The present invention concerns an integrated circuit structure (1) formed in a substrate (2) and including at least one integrated circuit element (3, 4), an antenna coil (5) capable of transmitting and/or receiving data, and associated with said integrated circuit element(s) (3, 4); and a metal protective ring (20) situated at the periphery of the integrated circuit structure (1). The present invention is characterised in that said protective ring (20) comprises at least one ohmic interruption, so that it does not form a closed circuit on itself. The integrated circuit structure (1) according to the invention is improved in that the operation of the antenna coil (5) is made insensitive to the presence of the protective ring (20).

Claims

1. An integrated circuit structure formed in a semiconductor substrate and including:

at least one electronic integrated circuit element;

an antenna coil arranged to receive data and energy to supply said electronic integrated circuit element; and

a metal protective ring situated at the periphery of said electronic integrated circuit structure to protect elements of said electronic integrated circuit structure from mechanical stress or corrosion;

wherein said protective ring is arranged with at least one ohmic interruption, so that it does not form a closed circuit on itself, in order that the antenna coil is insensitive to the presence of the protective ring, thereby enabling operation of said electronic integrated circuit element.

2. The integrated circuit structure of claim 1, wherein said antenna coil and said electronic integrated circuit element together define a transponder.

3. The integrated circuit structure of claim 1, wherein said protective ring is arranged with four ohmic interruptions.

4. A method for manufacturing an integrated circuit structure formed in a semiconductor substrate, said method comprising the steps:

manufacturing at least one electronic integrated circuit element in a semiconductor substrate;

manufacturing an antenna coil arranged to receive data and energy to supply said electronic integrated circuit element; and

manufacturing a metal protective ring situated at the periphery of said integrated circuit structure, said protective ring being arranged with at least one ohmic interruption, so that it does not form a closed circuit on itself, in order that the antenna coil is insensitive to the presence of the protective ring, thereby enabling operation of said integrated circuit structure.

5. The method of claim 4, wherein said protective ring is arranged with four ohmic interruptions.

6. A method for manufacturing an integrated circuit structure formed in a semiconductor substrate, said method comprising the steps:

manufacturing at least one electronic integrated circuit element in a semiconductor substrate;

manufacturing an antenna coil arranged to receive data and energy to supply said electronic integrated circuit element; and

manufacturing a metal protective ring situated at the periphery of said integrated circuit structure to protect elements of said integrated circuit structure against mechanical stress or corrosion, said protective ring being arranged with at least one ohmic interruption, so that it does not form a closed circuit on itself, in order that the antenna coil is insensitive to the presence of the protective ring, thereby enabling operation of said integrated circuit structure.

7. The method of claim 6, wherein said protective ring is arranged with four ohmic interruptions.