Metal contactless smart card and method for fabricating the same

1. A smart card for financial transactions comprising:

a radio-frequency integrated circuit (RFIC) chip module ( 20 ) having a RFIC chip;

an inlay ( 40 ) having an antenna to enable contactless communication of the RFIC chip module ( 20 ) with an external reader;

a first metal layer ( 10 or 10 ′) having a through-hole ( 12 ) in which the RFIC chip module ( 20 ) is inserted and a recess ( 11 ) on which the inlay ( 40 ) is received;

a second layer ( 60 or 80 ) attached to a lower side of the first metal layer; and

a first slit ( 15 or 15 ′) formed in the first metal layer ( 10 or 10 ′) and disposed from the through-hole ( 12 ) to an outer edge of the first metal layer ( 10 r 10 ′),

wherein when a current is induced by an applied magnetic field, the current in the first metal layer ( 10 or 10 ′) is concentrated along the first slit ( 15 or 15 ′),

wherein the first slit ( 15 or 15 ′) enhances contactless communication of the RFIC chip module ( 20 ) with an external reader,

wherein the inlay ( 40 ) comprises a substrate, the antenna having a first wound coil ( 42 ) and a second wound coil ( 42 ′), and two inlay terminals ( 41 and 41 ′),

wherein he inlay terminals ( 41 and 41 ′) are formed to pass through the substrate of the inlay ( 40 ) as to be exposed on both sides of the inlay ( 40 ),

wherein the inlay terminals ( 41 and 41 ′) are formed at the ends of the first wound coil ( 42 ) and the second wound coil ( 42 ′),

wherein the first wound coil ( 42 ) is formed on a surface of the substrate of the inlay ( 40 ) and the second coil ( 42 ′) is formed on an opposite surface of the substrate of the inlay( 40 ),

wherein the two coils ( 42 and 42 ′) are connected by a via hole ( 43 ) formed through the substrate of the inlay ( 40 ),

wherein the inlay terminals ( 41 and 41 ′) are electrically connected to two RFIC chip module terminals ( 14 and 14 ′),

wherein one of the two coils ( 42 and 42 ′) further comprises a wide portion ( 42 a ) and the other of the two coils ( 42 and 42 ′) further comprises a plurality of islands ( 44 and 44 ′), wherein the overall capacitance of the inlay may be adjusted by

electrically insulating a number of islands ( 44 ′) and facilitate impedance matching.

2. The smart card of claim 1 , wherein the recess ( 11 ) surrounds the through-hole ( 12 ).

3. The smart card of claim 1 , wherein the first slit ( 15 or 15 ′) is at least 0.1 mm in width.

4. The smart card of claim 1 , wherein the cross-sectional profile of the first slit ( 15 ′) is wider on the lower side of the first metal layer ( 10 ′) than an upper side of the first metal layer ( 10 ′).

5. The smart card of claim 1 , wherein the second layer ( 60 ) is made of a synthetic resin.

6. The smart card of claim 1 , wherein the second layer ( 80 ) is metallic and comprises a second slit ( 85 ), wherein the second slit ( 85 ) is disposed from an interior portion of the second layer ( 80 ) to an edge of the second layer ( 80 ).

7. The smart card of claim 6 , wherein the second slit ( 85 ) is disposed to be substantially aligned with the first slit ( 15 ).

8. The smart card of claim 7 further comprising an insert ( 90 ) disposed in the slits ( 15 , 85 ), wherein the insert ( 90 ) has a shape corresponding to the stacked slits ( 15 , 85 ).

9. The smart card of claim 6 further comprising a connection layer ( 70 ) disposed between the first layer ( 10 ) and the second layer ( 80 ),

wherein the connection layer ( 70 ) is made of a nonconductive material.

10. The smart card f claim 1 further comprising a PVC thin film ( 50 ) received in the recess ( 11 ) and disposed between the second layer ( 60 ) and the inly ( 40 ).

11. A smart card for financial transactions comprising:

a radio-frequency integrated circuit (RFIC) chip module ( 20 ) having a RFIC chip;

an inlay ( 40 ) having an antenna to enable contactless communication of the RFIC chip module ( 20 ) with an external reader;

a first metal layer ( 10 or 10 ′) having a through-hole ( 12 ) in which the RFIC chip module ( 20 ) is inserted and a recess ( 11 ) on which the inlay ( 40 ) is received;

a second layer ( 60 or 80 ) attached to a lower side of the first metal layer; and

a first slit ( 15 or 15 ′) formed in the first metal layer ( 10 or 10 ′) and disposed from the through-hole ( 12 ) to an outer edge of the first metal layer ( 10 or 10 ′),

wherein when a current is induced by an applied magnetic field, the current in the first metal layer ( 10 or 10 ′) is concentrated alone the first slit ( 15 or 15 ′),

wherein the first slit ( 15 or 15 ′) enhances contactless communication of the RFIC chip module ( 20 ) with an external reader,

wherein the second layer ( 80 ) is metallic and comprises a second slit ( 85 ), wherein the second slit ( 85 ) is disposed from an interior portion of the second layer ( 80 ) to an edge of the second layer ( 80 ),

wherein the second slit ( 85 ) is disposed to be substantially aligned in a lengthwise direction with the first slit ( 15 ) and shifted in a widthwise direction with respect to the first slit ( 15 ) by less than the width of the first slit ( 15 ),

wherein the second slit and the first slit comprise a stacked slit having a s-shaped cross-section and an insert having a shape corresponding to the stacked slit is snugly fit in the stacked slit.

12. A smart card for financial transactions comprising:

a radio-frequency integrated circuit (RFIC) chip module ( 20 ) having a RFIC chip;

an inlay ( 40 ) having an antenna to enable contactless communication of the RFIC chip module ( 20 ) with an external reader;

a first metal Layer ( 10 or 10 ′) having a through-hole ( 12 ) in which the RFIC chip module ( 20 ) is inserted and a recess ( 11 ) on which the inlay ( 40 ) is received;

a second layer ( 60 or 80 ) attached to a lower side of the first metal layer;

a first slit ( 15 or 15 ′) formed in the first metal layer ( 10 or 10 ′) and disposed from the through-hole ( 12 ) to an outer edge of the first metal layer ( 10 or 10 ′),

wherein when current is induced by an applied magnetic field, the current in the first metal layer ( 10 or 10 ′) is concentrated along the first slit ( 15 or 15 ′),

wherein the first slit ( 15 or 15 ′) enhances contactless communication of the RFIC chip module ( 20 ) with an external reader; and

an insert ( 90 ) having a shape corresponding to the slit ( 15 ), wherein the insert( 90 ) is made of a nonconductive material,

wherein the insert ( 90 ′) comprises a rod-shaped body ( 90 a ), having a length dimension corresponding to a length extending from the through-hole to the outer edge of the first metal layer, with a left wing and a right wing ( 90 b ),

wherein the left wing and right wing ( 90 b ) are formed on opposite sides of the rod-shaped body ( 90 a ),

wherein the left wing and right wing ( 90 b ) are smaller than the rod-shaped body ( 90 a ).

13. The smart card of claim 12 further comprising a thin film ( 90 c ) formed on an end of the insert ( 90 ),

wherein the thin film ( 90 c ) is made of a nonconductive material and is received in the inlay groove ( 11 ) and disposed between the second layer ( 60 ) and the inlay ( 40 ).