Abstract:
A method includes a step of preparing a strap having a connecting metal pattern formed on a base, and mounted with the circuit chip, the pattern connecting a circuit chip to a metal antenna pattern. A substrate has a concave section which houses the circuit chip and is formed on a first face. The metal antenna pattern extends over a first face and a second face of the base so as to circle them except for the concave section and to have the both ends positioned across the concave section. The method includes a connection step of positioning and directing the strap and the substrate to house the circuit chip in the concave section and covering the strap and the substrate with a covering material so as to fix the strap and the substrate in a state where the connection metal pattern is connected to the metal antenna pattern.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under 35 U.S.C. Section 119, of Japanese Patent Application No. 2006-181815, filed Jun. 30, 2006, which is hereby incorporated by reference in its entirety into this application. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an RFID (Radio_Frequency_IDentification) tag for exchanging information with an external device in a noncontact manner. There are the cases where those in the art refer to the “RFID tag” used herein as an “RFID tag inlay” regarding it as an inlay for the “RFID tag.” There are also the cases where the “RFID tag” is referred to as a “Radio Frequency Identification.” The “RFID tag” also includes a noncontact IC card. 
     2. Description of the Related Art 
     In recent years, there have been proposed various kinds of RFID tags for exchanging information with an external device represented by a reader-writer in a noncontact manner via radio waves. There has been proposed a kind of the RFID tag having a configuration in which an antenna pattern for radio communication and an IC chip are mounted on a base sheet consisting of plastic or paper (see, for example, Japanese Patent Laid-Open No. 2000-311226, Japanese Patent Laid-Open No. 2000-200332, Japanese Patent Laid-Open No. 2001-351082). A conceivable form of use for such a type of the RFID tag is to attach it to an article or the like and exchange the information on the article with the external device to identify the article. 
       FIG. 1  is a plan view showing an example of the RFID tag. 
     An RFID tag  1  shown in this  FIG. 1  is configured by an antenna  12  provided on a base  13  consisting of a sheet-like PET film and the like and an IC chip  11  electrically connected to the antenna  12  by gold, solder or the like and firmly fixed to the base  13  by an adhesive. 
     The IC chip  11  configuring the RFID tag  1  can perform radio communication with the external device via the antenna  12  and exchange information. 
     Here,  FIG. 1  shows a looped antenna as the antenna  12  of the RFID tag  1 . As for the RFID tags in general, however, the antenna  12  is not limited to this form. It is possible to adopt the antennas in various forms such as the antenna in the form having the IC chip  11  at its center and linearly extending to both sides from the IC chip  11 . 
     The RFID tag as described above may have its communication performance significantly deteriorated by a piece of metal or the like if one exists in proximity thereto. To prevent this, an RFID tag called a metal tag is known. The metal tag is an RFID tag of a structure having a substrate surrounded by a metal pattern operating as the antenna, where the communication performance is maintained even if another piece of metal or the like approaches except for a portion in which the piece of metal becomes a shadow. 
     Here, a conventional manufacturing method of the metal tag will be described. 
       FIGS. 2A and 2B  are perspective views of parts used for manufacturing of the metal tag. 
     Here, the IC chip  11  ( FIG. 2A ) and a substrate  20  for the metal tag ( FIG. 2B ) are prepared. 
     As shown in  FIG. 2A , the IC chip  11  has a bump  11   a  of gold or the like formed on its connecting terminal. In  FIG. 2A , the IC chip  11  is shown upside down as compared to the IC chip  11  shown in  FIG. 1  in order to show a forming face of the bump  11   a . The IC chip  11  has a function of performing radio communication with an external device via the antenna (described later) and exchanging information (refer to  FIG. 1 ). 
     The substrate  20  has a metal antenna pattern  22 , which operates as the antenna after assembly, formed on a dielectric plate  21  and surrounding it except for a portion  23  on which the IC chip  11  is to be mounted. 
       FIGS. 3A ,  3 B and  3 C are process drawings showing an example of the manufacturing method of the metal tag. 
     Here, a liquid or sheet-like underfill  24  which is a thermosetting adhesive is supplied to the portion  23  of the substrate  20  on which the IC chip  11  is to be mounted ( FIG. 3A ). The IC chip  11  is put on the portion  23 , and the substrate  20  and the IC chip  11  are sandwiched by a heating stage  31  and a heating head  32  to be heated and pressed. Thus, the IC chip  11  and the metal antenna pattern  22  are electrically connected via the bump  11   a , and the IC chip  11  is fixed on the substrate  20  as the underfill  24  ( FIG. 3B ) hardens. 
     The RFID tag of the structure shown in  FIG. 3C  is manufactured by undergoing such a process flow. The RFID tag performs radio communication with the external device by means of the IC chip  11  via a loop antenna in the form surrounding and circling front and rear faces of the dielectric plate  21 . 
     This type of the RFID tag is referred to as a so-called metal tag, where the communication performance is sufficiently secured as to the front side of the substrate  20  on which the IC chip  11  is mounted even if another piece of metal approaches the rear side opposite to the front side on which the IC chip  11  is mounted. 
     However, the RFID tag formed by the manufacturing method described with reference to  FIGS. 2 and 3  has the IC chip  11  mounted on the substrate  20  projected from the front face of the substrate  20 , which is difficult to render flat and thin. To solve this, it is supposedly possible to render thickness of the substrate  20  thinner. However, a certain distance is required between the substrate front face portion and the substrate rear face portion of the metal antenna pattern  22  in order to secure expected performance of the metal antenna pattern  22  as the loop antenna. Therefore, there is a limit to rendering the substrate  20  thinner from the viewpoint of securing antenna performance. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in view of the circumstances, and provides a manufacturing method of an RFID tag rendered thinner and flatter and having performance as a metal tag, and the RFID tag manufactured by the manufacturing method. 
     The present invention provides a first manufacturing method of an RFID tag as the manufacturing method of an RFID tag including: 
     a preparation step of preparing a strap and a substrate, the strap having a connecting metal pattern formed on a base, the connecting metal pattern connecting a circuit chip performing radio communication via an antenna after assembly to a metal antenna pattern operating as the antenna after the assembly, the strap mounted with the circuit chip, the substrate having a concave section, which houses the circuit chip, formed on a first face constituting one of top and bottom faces, and the metal antenna pattern having both ends thereof positioned so as to sandwich the concave section, extending to the first face and a second face opposite to the first face and surrounding the first and second faces except for the concave section; and 
     a connection step of positioning and directing the strap and the substrate to house the circuit chip on the strap in the concave section formed on the substrate, fixing the strap and the substrate to each other in a state where the connecting metal pattern on the strap is connected to the metal antenna pattern on the substrate, by covering the strap and the substrate with a covering material. 
     According to the first manufacturing method of an RFID tag of the present invention, the circuit chip of the strap is housed in the concave section of the substrate so as to render the RFID tag thinner and flatter. 
     The first manufacturing method of an RFID tag of the present invention is preferably the one wherein the connection step includes: 
     a provisional connection step of placing the strap on the substrate at a position and in a direction to house the circuit chip on the strap in the concave section formed on the substrate and provisionally connecting the connecting metal pattern on the strap to the metal antenna pattern on the substrate; and 
     a fixing step of covering the strap and the substrate with the covering member with the strap placed on the substrate to fix the strap and the substrate mutually. 
     Manufacturing time of the RFID tag is shortened by adopting such a preferable connection step so that efficient manufacturing is realized. 
     Here, the fixing step may be the step of either: 
     covering the strap and the substrate with the heat softening covering material and attaching the covering member to the strap and the substrate by heating the covering member to fix the strap and the substrate mutually; or 
     covering the strap and the substrate with the covering member having an adhesion layer on its inner face and thereby attaching the covering member to the strap and the substrate to fix the strap and the substrate mutually. 
     An inexpensive PET and the like can be used as the covering member in the form of heating the covering member to fix the strap and the substrate mutually. Simple and quick fixing work is performed in the form of attaching the covering member having the adhesion layer on its inner face to fix the strap and the substrate mutually. 
     The provisional connection step may be the step of either: 
     putting the connecting metal pattern in physical contact with the metal antenna pattern to provisionally connect them; or 
     temporarily joining the connecting metal pattern to the metal antenna pattern to provisionally connect them. 
     The form of putting them in physical contact is a simple and easy form. The form of temporarily joining them can prevent displacement of the strap from after the provisional connection to before fixation. 
     Furthermore, it is a preferable form wherein: 
     the provisional connection step is a step of temporarily joining the connecting metal pattern to the metal antenna pattern with a conductive adhesive to be hardened by heat so as to make a provisional connection; and 
     the fixing step is a step of covering the strap and the substrate with the heat softening covering material and attaching the covering member to the strap and the substrate by heating the covering member and also fixing the strap and the substrate mutually by hardening the adhesive. 
     According to this preferable form, the temporarily joined portion is hardened by the heat applied in the fixing step so that endurance of the RFID tag is improved and the manufacturing time is reduced. 
     The first manufacturing method of an RFID tag of the present invention is preferably the one wherein the connection step includes: 
     a placement step of placing the strap on the adhesion layer of the covering member having the adhesion layer on its inner face when covering; and 
     a fixing step of positioning the substrate against the strap placed on the adhesion layer at the position and in the direction to house the circuit chip on the strap in the concave section formed on the substrate and covering the strap and the substrate with the covering member so as to fix the strap and the substrate mutually. 
     It is possible, by adopting such a preferable connection step, to avoid the displacement before fixing the strap and the substrate mutually so as to improve accuracy of manufacturing. 
     The present invention provides a first RFID tag including: 
     a strap having a connecting metal pattern formed on a base, the connecting metal pattern connecting a circuit chip performing radio communication via an antenna after assembly to a metal antenna pattern operating as the antenna after the assembly, the strap mounted with the circuit chip; 
     a substrate having a concave section, which houses the circuit chip, formed on a first face constituting one of top and bottom faces, and the metal antenna pattern having both ends thereof positioned so as to sandwich the concave section, extending to the first face and a second face opposite to the first face and surrounding the first and second faces except for the concave section; and 
     a covering member which covers and fixes the strap and the substrate to each other in a state where the strap is placed on the substrate at a position and in a direction to house the circuit chip on the strap in the concave section formed on the substrate and the connecting metal pattern on the strap is in physical contact with the metal antenna pattern on the substrate. 
     According to the first RFID tag of the present invention, it is a thin and flat RFID tag with the circuit chip of the strap housed in the concave section of the substrate. The strap and the substrate are mutually fixed by covering them with the covering member so as to contribute to reduction in manufacturing time. 
     The first RFID tag of the present invention is the one wherein the covering member may be either: 
     softened by heat and attached to the strap and the substrate; or attached to the strap and the substrate by an adhesion layer included on its inner face. 
     In the case of the covering member softened by heat and attached, a typical covering material such as a PET film is usable. In the case of the covering member attached by the adhesion layer, the process of adhesion is simple enough to contribute to reduction in manufacturing time. 
     The present invention provides a second manufacturing method of an RFID tag as the manufacturing method of an RFID tag including: 
     a preparation step of preparing a strap and a substrate, the strap having a connecting metal pattern formed on a base, the connecting metal pattern connecting a circuit chip performing radio communication via an antenna after assembly to a metal antenna pattern operating as the antenna after the assembly, the strap mounted with the circuit chip, the substrate having a concave section, which houses the circuit chip, formed on a first face constituting one of top and bottom faces, and the metal antenna pattern having both ends thereof positioned so as to sandwich the concave section, extending to the first face and a second face opposite to the first face and surrounding the first and second faces except for the concave section; and 
     a connection step of connecting metal pattern on the strap to the metal antenna pattern on the substrate, by placing the strap on the substrate at a position and in a direction to house the circuit chip on the strap in the concave section formed on the substrate and applying ultrasound to the strap. 
     According to the second manufacturing method of an RFID tag of the present invention, the circuit chip of the strap is housed in the concave section of the substrate so as to render the RFID tag thinner and flatter. The manufacturing time is short because the connection by the ultrasound is adopted. 
     The present invention provides a second RFID tag as the RFID tag including: 
     a strap having a connecting metal pattern formed on a base, the connecting metal pattern connecting a circuit chip performing radio communication via an antenna after assembly to a metal antenna pattern operating as the antenna after the assembly, the strap mounted with the circuit chip; and 
     a substrate having a concave section, which houses the circuit chip, formed on a first face constituting one of top and bottom faces, and the metal antenna pattern having both ends thereof positioned so as to sandwich the concave section, extending to the first face and a second face opposite to the first face and surrounding the first and second faces except for the concave section, 
     wherein the strap has ultrasound applied thereto by being placed on the substrate at a position and in a direction to house the circuit chip on the strap in the concave section formed on the substrate, and the connecting metal pattern on the strap is thereby connected to the metal antenna pattern on the substrate. 
     According to the second RFID tag of the present invention, it is a thin and flat RFID tag with the circuit chip of the strap housed in the concave section of the substrate. The manufacturing time is short because the connection by the ultrasound is adopted. 
     The present invention provides a third manufacturing method of an RFID tag as the manufacturing method of an RFID tag including: 
     a preparation step of preparing a strap and a substrate, the strap having a connecting metal pattern formed on a base, the connecting metal pattern connecting a circuit chip performing radio communication via an antenna after assembly to a metal antenna pattern operating as the antenna after the assembly, the strap mounted with the circuit chip, the substrate having a concave section, which houses the circuit chip, formed on a first face constituting one of top and bottom faces, and the metal antenna pattern having both ends thereof positioned so as to sandwich the concave section, extending to the first face and a second face opposite to the first face and surrounding the first and second faces except for the concave section; and 
     a connection step of connecting the connecting metal pattern on the strap to the metal antenna pattern on the substrate by placing and pinning the strap on the substrate at a position and in a direction to house the circuit chip on the strap in the concave section formed on the substrate. 
     According to the third manufacturing method of an RFID tag of the present invention, the RFID tag is rendered thinner and flatter by housing the circuit chip of the strap in the concave section of the substrate. The manufacturing time is short because the connection by pinning is adopted. 
     The present invention provides a third RFID tag as the RFID tag including: 
     a strap having a connecting metal pattern formed on a base, the connecting metal pattern connecting a circuit chip performing radio communication via an antenna after assembly to a metal antenna pattern operating as the antenna after the assembly, the strap mounted with the circuit chip; and 
     a substrate having a concave section, which houses the circuit chip, formed on a first face constituting one of top and bottom faces, and the metal antenna pattern having both ends thereof positioned so as to sandwich the concave section, extending to the first face and a second face opposite to the first face and surrounding the first and second faces except for the concave section, 
     wherein the strap is placed and pinned on the substrate at a position and in a direction to house the circuit chip on the strap in the concave section formed on the substrate, and thereby the connecting metal pattern on the strap is connected to the metal antenna pattern on the substrate. 
     According to the third RFID tag of the present invention, it is a thin and flat RFID tag with the circuit chip of the strap housed in the concave section of the substrate. The manufacturing time is short because the connection by pinning is adopted. 
     As described above, it is possible to obtain the RFID tag rendered thinner and flatter according to the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a plan view showing an example of an RFID tag; 
         FIGS. 2A and 2B  are perspective views of parts used for manufacturing of a metal tag; 
         FIGS. 3A ,  3 B and  3 C are process drawings showing an example of the manufacturing method of a metal tag; 
         FIGS. 4A and 4B  are perspective views showing the parts used in common in the manufacturing methods; 
         FIGS. 5A-1  through  5 E- 1  are process drawings showing a manufacturing method of a strap; 
         FIGS. 6A  through  FIG. 6D  are process drawings showing a first manufacturing method of an RFID tag; 
         FIGS. 7A ,  7 B and  7 C are process drawings showing a first half of a second manufacturing method of an RFID tag; 
         FIGS. 8A ,  8 B and  8 C are process drawings showing a second half of the second manufacturing method of an RFID tag; 
         FIGS. 9A ,  9 B and  9 C are process drawings showing a third manufacturing method of an RFID tag; 
         FIGS. 10A through 10E  are process drawings showing a fourth manufacturing method of an RFID tag; 
         FIGS. 11A through 11E  are process drawings showing a fifth manufacturing method of an RFID tag; and 
         FIGS. 12A through 12C  are process drawings showing a sixth manufacturing method of an RFID tag. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Embodiments of the present invention will be described hereunder with reference to the drawings. 
       FIGS. 4A and 4B  are perspective views showing parts used in common in manufacturing methods described hereunder. 
     A strap  120  shown in  FIG. 4A  and a substrate  130  shown in  FIG. 4B  are prepared in the embodiments described hereunder. 
     The strap  120  of  FIG. 4A  has a connecting metal pattern  122  formed on a base  121  of a PET film or the like, and further has an IC chip  11  electrically connected to the connecting metal pattern  122  mounted thereon. The IC chip  11  has a gold bumps formed thereon as with the IC chip shown in  FIG. 2A , and has a function of performing radio communication with outside via an antenna described later (refer to  FIG. 1 ). 
     A substrate  130  of  FIG. 4B  has a metal antenna pattern  132  formed on a dielectric plate  131  having a concave section  133  for housing the IC chip  11  formed thereon, the metal antenna pattern  132  circling front and rear faces except for the concave section  133 . 
     Next, a manufacturing method of the strap  120  shown in  FIG. 4A  will be described. 
       FIGS. 5A-1  through  5 E- 1  are process drawings showing the manufacturing method of the strap. 
     Here, a long strap sheet  120 A is prepared first. 
     As shown in  FIG. 5A-1 , the strap sheet  120 A has multiple connecting metal patterns  122  formed on the long base  121  consisting of the PET film or the like.  FIG. 5A-2  is a sectional view of a portion of the strap sheet  120 A equivalent to one connecting metal pattern. 
     The connecting metal pattern  122  is divided into two pieces, and an IC chip is mounted at the center thereof. 
     Next, a liquid or sheet-like underfill  123  which is a thermosetting adhesive is supplied to an IC chip mounting position of each of the connecting metal patterns  122  formed on the strap sheet  120 A (refer to  FIGS. 5B-1  and  5 B- 2 ). Here, the liquid underfill  123  is dropped by using a nozzle  33  as shown in  FIG. 5B-2 . 
     Next, the IC chip  11  is mounted over where the liquid underfill  123  was applied (refer to  FIGS. 5C-1  and  5 C- 2 ), and is sandwiched between a heating stage  31  and a heating head  32  (refer to  FIGS. 5D-1  and  5 D- 2 ) to be heated and pressed by the heating stage  31  and the heating head  32 . Thus, the IC chip  11  is electrically connected to the connecting metal pattern  122  via the bumps  11   a , and the IC chip  11  is fixed on the strap sheet  120 A as the underfill  123  hardens. 
     Furthermore, the strap sheet  120 A is rendered as a piece of the strap  120  (refer to  FIG. 4A ) including one IC chip and one connecting metal pattern  122  by punching, cutting or the like. 
     Next, a description will be given as to a manufacturing method of an RFID tag using the strap  120  shown in  FIG. 4A  thus manufactured and the substrate  130  manufactured separately therefrom shown in  FIG. 4B . Preparations for the strap  120  and the substrate  130  described in  FIG. 4  are equivalent to an example of the preparation step according to the present invention, and so a description of the preparation step will be omitted in the following. 
       FIGS. 6A through 6D  are process drawings showing a first manufacturing method of an RFID tag. 
     According to the first manufacturing method, the metal antenna pattern  132  and the concave section  133  on the substrate  130  are aligned with the IC chip  11  on the strap  120  ( FIG. 6A ) in order to place the strap  120  on the substrate  130  ( FIG. 6B ). In this case, the connecting metal pattern  122  on the strap  120  (refer to  FIG. 4 ) makes a physical contact with the metal antenna pattern  132  on the substrate  130  in a state where the IC chip  11  is housed in the concave section  133  of the substrate  130  so as to realize a provisional electric connection. 
     Next, the strap  120  and the substrate  130  in the state shown in  FIG. 6B  are sandwiched by covering sheets  140  consisting of a PET film or the like, and are sandwiched to be heated and pressed by the heating stage  34  and the heating head  35  (refer to  FIG. 6C ). The covering sheets  140  are thereby softened to cover and fix the strap  120  and the substrate  130  to each other ( FIG. 6D ). 
     An RFID tag  100  thus manufactured has a loop antenna formed thereon in the form of surrounding and circling front and rear faces of the dielectric plate  131  by the connecting metal pattern  122  on the strap  120  (refer to  FIG. 4 ) and the metal antenna pattern  132  on the substrate  130 . The IC chip  11  performs radio communication with an external device via the loop antenna. The RFID tag  100  thus manufactured has the IC chip  11  housed in the concave section  133  provided on the substrate  130  so as to be rendered thinner and flatter. 
     The first manufacturing method described above is a simple and low-cost manufacturing method since it adopts the method of simply placing the strap  120  on the substrate  130  as shown in  FIG. 6B  as an example of the provisional connection step according to the present invention. 
     Next, a second manufacturing method of an RFID tag will be described. 
       FIGS. 7A through 7C  are process drawings showing a first half of the second manufacturing method of an RFID tag.  FIGS. 8A through 8C  are process drawings showing a second half of the second manufacturing method of an RFID tag. 
     According to the second manufacturing method, first, a thermosetting silver paste  134  which is a kind of a conductive adhesive is supplied to the both ends of the metal antenna pattern  132  across the concave section  133  on the substrate  130  by a nozzle  36  of a dispenser ( FIG. 7A ). It is possible, instead of supplying the silver paste with the nozzle  36 , to print the silver paste on those portions. 
     Next, the silver paste  134  is semi-hardened by heating it for a short time ( FIG. 7B ), and the metal antenna pattern  132  and the concave section  133  on the substrate  130  are aligned with the IC chip  11  on the strap  120  ( FIG. 7C ) to place the strap  120  on the substrate  130  ( FIG. 8A ). Thus, in the state where the IC chip  11  is housed in the concave section  133  of the substrate  130 , the connecting metal pattern  122  on the strap  120  (refer to  FIGS. 4A and 4B ) and the metal antenna pattern  132  on the substrate  130  are temporarily joined to be provisionally connected electrically, and the strap  120  is temporarily fixed on the substrate  130 . 
     Next, the strap  120  and the substrate  130  in the state shown in  FIG. 8A  are sandwiched by covering sheets  140  consisting of the PET film or the like, and are heated and pressed by the heating stage  34  and heating head  35 , being sandwiched therebetween (refer to  FIG. 8B ). The covering sheets  140  are thereby softened to cover the strap  120  and the substrate  130 , and the semi-hardened silver paste becomes completely hardened to fix the strap  120  and the substrate  130  mutually ( FIG. 8C ). 
     An RFID tag  200  thus manufactured has a loop antenna formed thereon in the form of surrounding and circling the front and rear faces of the dielectric plate  131  by the connecting metal pattern  122  on the strap  120  (refer to  FIGS. 4A and 4B ) and the metal antenna pattern  132  on the substrate  130 . The IC chip  11  performs radio communication with an external device via the loop antenna. The RFID tag  200  also has the IC chip  11  housed in the concave section  133  provided on the substrate  130  so as to be rendered thinner and flatter. Furthermore, the RFID tag  200  has the strap  120  connected to the substrate  130  by the silver paste, and so it is more durable than the RFID tag  100  shown in  FIG. 6D . 
     The second manufacturing method described above adopts a method of provisionally fixing the strap  120  on the substrate  130  with the semi-hardened silver paste as shown in  FIGS. 7C and 8A  as an example of the provisional connection step according to the present invention. Therefore, the method avoids a possibility of displacement before the strap  120  is finally and completely fixed on the substrate  130  so that accuracy in manufacturing is high. The heating in the step of  FIG. 8B  realizes both the covering with the covering sheets  140  and hardening of the silver paste, so that manufacturing time is reduced. 
     Next, a third manufacturing method of an RFID tag will be described. The third manufacturing method undergoes the same steps as the first manufacturing method of an RFID tag up to the step of  FIG. 6B . Therefore, the subsequent steps after the step of  FIG. 6B  will be described. 
       FIGS. 9A through 9C  are process drawings showing the third manufacturing method of an RFID tag. 
     According to the third manufacturing method, the strap  120  and the substrate  130  in the state shown in  FIG. 6B  are sandwiched by covering sheets  150  consisting of a sheet base member  151  such as a PET film and an adhesive layer  152  ( FIG. 9A ), and are pressed by being sandwich between a pressing stage  37  and a pressing head  38  (refer to  FIG. 9B ). The covering sheets  150  are thereby attached to the strap  120  and the substrate  130  to be fixed mutually and cover the strap  120  and the substrate  130  ( FIG. 9C ). 
     An RFID tag  300  thus manufactured is rendered thinner and flatter as with the RFID tag  100  shown in  FIG. 6D . 
     The third manufacturing method described above is a low-cost and short-time manufacturing method which requires no heating since it adopts the method of attaching the covering sheets  150  including the adhesive layer  152  to the strap  120  and the substrate  130  to be fixed mutually as an example of the fixing step according to the present invention. 
     Next, a fourth manufacturing method of an RFID tag will be described. The fourth manufacturing method is a manufacturing method for manufacturing the same RFID tag as the RFID tag  300  shown in  FIG. 9C . 
       FIGS. 10A through 10E  are process drawings showing the fourth manufacturing method of an RFID tag. 
     According to the fourth manufacturing method, the strap  120  is placed and attached on the adhesive layer  152  of the covering sheets  150  consisting of the sheet base member  151  such as the PET film and adhesive layer  152  ( FIGS. 10A and 10B ). Next, the metal antenna pattern  132  and the concave section  133  on the substrate  130  are aligned with the IC chip  11  on the strap  120  ( FIG. 10C ) to place the substrate  130  on the strap  120 . The strap  120  and the substrate  130  are sandwiched by the covering sheets  150 , and are pressed by being sandwiched between the pressing stage  37  and pressing head  38  (refer to  FIG. 10D ). Thus, the same RFID tag  300  as the RFID tag  300  shown in  FIG. 9C  is manufactured. 
     Next, a fifth manufacturing method of an RFID tag will be described. The fifth manufacturing method undergoes the same steps as the first manufacturing method of an RFID tag up to the step of  FIG. 6B . Therefore, the following will describe the steps thereafter. 
       FIGS. 11A through 11E  are process drawings showing the fifth manufacturing method of an RFID tag. 
     According to the fifth manufacturing method, pins  40  are pushed from the strap  120  side into the strap  120  and the substrate  130  ( FIG. 11A ) in the same state as the state shown in  FIG. 6B  by a pinhead  39  ( FIG. 11B ) so that the strap  120  and the substrate  130  are fixed to each other ( FIG. 11C ). Accordingly, the connecting metal pattern  122  on the strap  120  (refer to  FIG. 4 ) and the metal antenna pattern  132  on the substrate  130  are put in physical contact and fixed by the pins  40  in the state where the IC chip  11  is housed in the concave section  133  of the substrate  130  so as to realize an electric connection. 
     Next, the strap  120  and the substrate  130  thus fixed to each other by the pins  40  are sandwiched by the covering sheets  140  consisting of the PET film or the like, and are heated and pressed by being sandwiched between the heating stage  34  and the heating head  35  (refer to  FIG. 11D ). The covering sheets  140  are thereby softened to cover the strap  120  and the substrate  130 , so that an RFID tag  400  is obtained. 
     The strap  120  and the substrate  130  are completely fixed to each other by the steps up to  FIG. 11C , and so the step of  FIG. 11D  is omissible. However, from the viewpoint of improving durability and the like, it is desirable to adopt the step of  FIG. 11D  and cover the strap  120  and the substrate  130  with the covering sheets  140 . 
     The RFID tag  400  thus manufactured has the IC chip  11  housed in the concave section  133  provided on the substrate  130  that is rendered thinner and flatter. 
     The fifth manufacturing method described above is a short-time manufacturing method of a small number of steps because the strap  120  and the substrate  130  are fixed to each other by the pins. 
     Lastly, a sixth manufacturing method of the RFID tag will be described. The sixth manufacturing method is performed through the same steps as the first manufacturing method of the RFID tag up to the step of  FIG. 6B . Therefore, the subsequent steps after the step shown in  FIG. 6B  will be described. 
       FIGS. 12A through 12C  are process drawings showing the sixth manufacturing method of an RFID tag. 
     According to the sixth manufacturing method, an ultrasonic vibration in a lateral direction of the drawing is applied from the strap  120  side to the strap  120  and the substrate  130  ( FIG. 12A ) in the same state as the state shown in  FIG. 6B  by an ultrasonic head  41  ( FIG. 12B ). A tip of the ultrasonic head  41  is sticking to and holding the strap  120 . As the ultrasonic vibration is applied, surfaces of both the connecting metal pattern  122  on the strap  120  (refer to  FIG. 4 ) and the metal antenna pattern  132  on the substrate  130  are vibrated to rub each other and melted instantaneously in the state where the IC chip  11  is housed in the concave section  133  of the substrate  130 . If application of the ultrasonic vibration is stopped thereafter, the melted surfaces are firmly fixed to each other to be electrically connected, and the strap  120  and the substrate  130  are fixed to each other. 
     Thereafter, the strap  120  and the substrate  130  are covered by the covering sheets  140  in the same step as the step of  FIG. 11D  so that an RFID tag  500  is obtained ( FIG. 12C ). 
     The strap  120  and the substrate  130  are completely fixed to each other through the steps up to  FIG. 12B , and so the covering by the covering sheets  140  is also omissible in the sixth manufacturing method. From the viewpoint of improving durability and the like, however, it is desirable to cover the strap  120  and the substrate  130  with the covering sheets  140 . 
     The RFID tag  500  thus manufactured also has the IC chip  11  housed in the concave section  133  provided on the substrate  130 , so that the RFID tag  500  is thinned and flattened. 
     The sixth manufacturing method described above is a short-time manufacturing method of a small number of steps because the strap  120  and the substrate  130  are fixed to each other by the ultrasonic vibration. 
     In the description above, the silver paste is used as an example of the conductive adhesive according to the present invention. However, the conductive adhesive according to the present invention may be other than the silver paste as long as the conductive adhesive is a thermosetting-type conductive adhesive. 
     In the description above, the covering sheets consisting of the PET film or the like is used as an example of the covering member according to the present invention. However, the covering member according to the present invention may be any material capable of covering and mutually fixing the strap and the substrate, for example, one which is a liquid before the covering. The covering member according to the present invention may also be the one having a cylindrical external form covering the strap and the substrate as a derivative one that is a little different from the object of the invention in terms of thinning. 
     In the description above, the example of adopting the silver paste which finally hardens completely is shown as an agent for temporarily joining the connecting metal pattern to the metal antenna pattern. However, according to the present invention, it is possible to adopt an adhesive working for the temporarily joining, which leaves final fixing to the covering member or the like without contributing to the final fixing.