Patent Publication Number: US-2022215998-A1

Title: Multilayer electronic component

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a multilayer electronic component including a stack and a shield covering a part of the surface of the stack. 
     2. Description of the Related Art 
     Recently, compact mobile communication apparatuses typified by cellular phones and smartphones have achieved greater functionality and further miniaturization, and the packing densities of electronic components have increased accordingly. As a result, spacings between the electronic components mounted on a mount substrate or distances from the electronic components to a shield case covering the electronic components have been reduced in the compact mobile communication apparatuses. 
     As the spacing between the electronic components is reduced, electromagnetic interference is more likely to occur between the electronic components. Further, as the distances between the shield case and the electronic components are reduced, the electronic components as packaged are more likely to have different characteristics than those as designed, due to capacitances formed by conductors inside the electronic components and the shield case. 
     To reduce electromagnetic interference between a plurality of electronic components and changes in the characteristics of the electronic components due to a shield case, electronic components such as the ones described in US 2018/0034436 A1 and US 2019/0198230 A1 have been known. US 2018/0034436 A1 describes a low-pass filter including a shield electrode formed on the side surfaces of a stack. US 2019/0198230 A1 describes a low-pass filter including a shield electrode disposed on the top surface and the side surfaces of a stack. 
     Compact mobile communication apparatuses are often configured to include an antenna that is used by both the system and a plurality of applications of different used frequency bands and use a branching filter to separate a plurality of signals for this antenna to transmit and receive. 
     A branching filter for separating a first signal of a frequency within a first frequency band and a second signal of a frequency within a second frequency band higher than the first frequency band from each other typically includes a common port, a first signal port, a second signal port, a first filter provided in a first signal path leading from the common port to the first signal port, and a second filter provided in a second signal path leading from the common port to the second signal port. 
     Suppose that a shield is formed on the surface of the branching filter. With the shield provided on the surface of the branching filter, the components of the filter can be capacitively coupled with the shield. The formation of capacitance by the capacitive coupling makes impedance matching difficult since the impedance of the filter becomes different from the designed one. The higher the passband of the filter is, the more likely that capacitive coupling will occur between the filter components and the shield. Thus, if the shield is formed on the surface of the foregoing branching filter that includes the first and second filters, the second filter is susceptible to the capacitive coupling and impedance matching will be difficult compared to the first filter. It has thus been difficult to achieve the desired characteristics. 
     The foregoing problem is not limited to branching filters and applies to multilayer electronic components in general that include a plurality of resonators and handle a plurality of signals of respective different frequencies. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a multilayer electronic component that can achieve desired characteristics while preventing the occurrence of an electromagnetic malfunction due to high density packaging. 
     A multilayer electronic component according to the present invention includes: a common port; a first signal port that selectively passes a first signal of a frequency within a first passband; a second signal port that selectively passes a second signal of a frequency within a second passband higher than the first passband; a first resonator provided between the common port and the first signal port in a circuit configuration; a second resonator provided between the common port and the second signal port in the circuit configuration; a stack for integrating the common port, the first signal port, the second signal port, the first resonator, and the second resonator, the stack including a plurality of dielectric layers and a plurality of conductor layers stacked together; and a shield that is formed of a conductor and covers a part of a surface of the stack. 
     The first and second resonators are formed using the plurality of conductor layers. The stack has a bottom surface and a top surface located at both ends in a stacking direction of the plurality of dielectric layers, and four side surfaces connecting the bottom surface and the top surface. The shield includes a specific portion opposed to both the first and second resonators. A distance between the second resonator and the specific portion is greater than a distance between the first resonator and the specific portion. 
     In the multilayer electronic component according to the present invention, the shield may include a side covering portion that covers one of the four side surfaces as at least a part of the specific portion. In such a case, a distance between the second resonator and the side covering portion may be greater than a distance between the first resonator and the side covering portion. 
     In the multilayer electronic component according to the present invention, the shield may include a top covering portion that covers the top surface as at least a part of the specific portion. In such a case, a distance between the second resonator and the top covering portion may be greater than a distance between the first resonator and the top covering portion. 
     In the multilayer electronic component according to the present invention, the first resonator may include at least one first inductor, and the second resonator may include at least one second inductor. In such a case, a distance between the at least one second inductor and the specific portion may be greater than a distance between the at least one first inductor and the specific portion. 
     In the multilayer electronic component according to the present invention, the first resonator may include at least one first capacitor, and the second resonator may include at least one second capacitor. In such a case, a distance between the at least one second capacitor and the specific portion may be greater than a distance between the at least one first capacitor and the specific portion. 
     The multilayer electronic component according to the present invention may further include a circuit that is provided between the common port and the first resonator in the circuit configuration and includes at least one element formed using the plurality of conductor layers. In such a case, the specific portion may be opposed to the circuit. A distance between the circuit and the specific portion may be greater than the distance between the first resonator and the specific portion. The element may be an inductor. 
     In the multilayer electronic component according to the present invention, the common port, the first signal port, and the second signal port may be provided on the bottom surface of the stack. In such a case, the shield may entirely cover the top surface and the four side surfaces. 
     The multilayer electronic component according to the present invention may further include a third signal port that selectively passes a third signal of a frequency within a third passband higher than the first passband and lower than the second passband, and a third resonator provided between the common port and the third signal port in the circuit configuration. The third resonator may be formed using the plurality of conductor layers. In such a case, the specific portion may be opposed to the third resonator. The distance between the second resonator and the specific portion may be greater than a distance between the third resonator and the specific portion. The distance between the third resonator and the specific portion may be greater than the distance between the first resonator and the specific portion. 
     In the multilayer electronic component according to the present invention, the first and second resonators are integrated with the stack. The shield covers a part of the surface of the stack. The shield includes the specific portion opposed to both the first and second resonators. The distance between the second resonator and the specific portion is greater than the distance between the first resonator and the specific portion. According to the present invention, a multilayer electronic component that can achieve desired characteristics can thus be implemented while preventing the occurrence of an electromagnetic malfunction due to high density packaging. 
     Other and further objects, features and advantages of the present invention will appear more fully from the following description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a circuit diagram showing a circuit configuration of a multilayer electronic component according to an embodiment of the invention. 
         FIG. 2  is an external perspective view showing the multilayer electronic component according to the embodiment of the invention. 
         FIG. 3  is a cross-sectional view of the multilayer electronic component of  FIG. 2 . 
         FIG. 4  is an internal perspective view showing a stack of the multilayer electronic component of  FIG. 2 . 
         FIG. 5  is an internal plan view showing the stack of the multilayer electronic component of  FIG. 2 . 
         FIG. 6A  to  FIG. 6C  are explanatory diagrams showing respective patterned surfaces of first to third dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 7A  to  FIG. 7C  are explanatory diagrams showing respective patterned surfaces of fourth to sixth dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 8A  to  FIG. 8C  are explanatory diagrams showing respective patterned surfaces of seventh to ninth dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 9A  to  FIG. 9C  are explanatory diagrams showing respective patterned surfaces of tenth to twelfth dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 10A  to  FIG. 10C  are explanatory diagrams showing respective patterned surfaces of thirteenth to fifteenth dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 11A  to  FIG. 11C  are explanatory diagrams showing respective patterned surfaces of sixteenth to eighteenth dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 12A  to  FIG. 12C  are explanatory diagrams showing respective patterned surfaces of nineteenth to twenty-first dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 13A  to  FIG. 13C  are explanatory diagrams showing respective patterned surfaces of twenty-second to twenty-fourth dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 14A  is an explanatory diagram showing a patterned surface of a twenty-fifth dielectric layer of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 14B  is an explanatory diagram showing a patterned surface of each of twenty-sixth to twenty-eighth dielectric layers of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 14C  is an explanatory diagram showing a patterned surface of a twenty-ninth dielectric layer of the stack shown in  FIG. 4  and  FIG. 5 . 
         FIG. 15  is a characteristic diagram showing an example of pass characteristic of the multilayer electronic component according to the embodiment of the invention. 
         FIG. 16  is a characteristic diagram showing an example of reflection characteristic of the multilayer electronic component according to the embodiment of the invention. 
         FIG. 17  is a characteristic diagram showing the insertion loss of a middle band filter determined by a simulation. 
         FIG. 18  is a characteristic diagram showing the return loss of the middle band filter determined by a simulation. 
         FIG. 19  is a characteristic diagram showing the insertion loss of a high band filter determined by a simulation. 
         FIG. 20  is a characteristic diagram showing the return loss of the high band filter determined by a simulation. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An embodiment of the present invention will now be described in detail with reference to the drawings. First, the configuration of a multilayer electronic component (hereinafter simply referred to as electronic component) according to the embodiment of the invention will be outlined with reference to  FIG. 1 . An electronic component  1  according to the present embodiment is a branching filter (triplexer) including a first filter, a second filter, and a third filter. The first filter selectively passes a first signal of a frequency within a first passband. The second filter selectively passes a second signal of a frequency within a second passband which is higher than the first passband. The third filter selectively passes a third signal of a frequency within a third passband which is higher than the first passband and lower than the second passband. 
     As shown in  FIG. 1 , the electronic component  1  includes a common port  2 , signal ports  3 ,  4 , and  5 , resonators  10 ,  20 , and  30 , and an LC circuit  40 . 
     The signal port  3  selectively passes the first signal of the frequency within the first passband. The resonator  10  is provided between the common port  2  and the signal port  3  in a circuit configuration. The resonator  10  constitutes the first filter. 
     The signal port  5  selectively passes the second signal of the frequency within the second passband. The resonator  30  is provided between the common port  2  and the signal port  5  in the circuit configuration. The resonator  30  constitutes the second filter. 
     The signal port  4  selectively passes the third signal of the frequency within the third passband. The resonator  20  is provided between the common port  2  and the signal port  4  in the circuit configuration. The resonator  20  constitutes the third filter. 
     The LC circuit  40  is provided between the common port  2  and the resonators  10  and  20  in the circuit configuration. In the present application, the expression of “in the(a) circuit configuration” is used to indicate not layout in physical configuration but layout in the circuit diagram. 
     The resonator  10  corresponds to “the first resonator” in the present invention. The resonator  20  corresponds to “the third resonator” of the present invention. The resonator  30  corresponds to “the second resonator” in the present invention. The signal port  3  corresponds to “the first signal port” in the present invention. The signal port  4  corresponds to “the third signal port” in the present invention. The signal port  5  corresponds to “the second signal port” in the present invention. 
     Next, an example of the configuration of the resonators  10 ,  20 , and  30  and the LC circuit  40  will be described with reference to  FIG. 1 . The resonators  10 ,  20 , and  30  each include at least one inductor and at least one capacitor. 
     The resonator  10  includes a port  11  connected to the LC circuit  40 , a port  12  connected to the signal port  3 , a path  13  connecting the ports  11  and  12 , inductors L 11  and L 12 , and capacitors C 11 , C 12 , and C 13 . The inductors L 11  and L 12  are provided in this order in series in the path  13  from the port  11  side. The capacitor C 11  is provided between a connection point of the inductors L 11  and L 12  and the ground. The capacitor C 12  is connected in parallel with the inductor L 12 . The capacitor C 13  is provided between the path  13  and the ground, between the inductor L 12  and the port  12 . 
     The resonator  20  includes a port  21  connected to the LC circuit  40 , a port  22  connected to the signal port  4 , a path  23  connecting the ports  21  and  22 , an inductor L 21 , and capacitors C 21 , C 22 , and C 23 . The capacitors C 21  and C 22  are provided in this order in series in the path  23  from the port  21  side. The capacitor C 23  is connected in parallel with the capacitors C 21  and C 22 . The inductor L 21  is provided between a connection point of the capacitors C 21  and C 22  and the ground. 
     The resonator  30  includes a port  31  connected to the common port  2 , a port  32  connected to the signal port  5 , a path  33  connecting the ports  31  and  32 , inductors L 31 , L 32 , L 33 , and L 34 , and capacitors C 31 , C 32 , C 33 , C 34 , C 35 , C 36 , and C 37 . The capacitors C 31  and C 32  and the inductors L 32  and L 34  are provided in this order in series in the path  33  from the port  31  side. The capacitor C 33  is connected in parallel with the capacitors C 31  and C 32 . The inductor L 31  is provided between a connection point of the capacitors C 31  and C 32  and the ground. The capacitor C 34  is connected in parallel with the inductor L 32 . The inductor L 33  is connected to a connection point of the inductors L 32  and L 34 . The capacitor C 35  is provided between the inductor L 33  and the ground. The capacitor C 36  is connected in parallel with the inductor L 34 . The capacitor C 37  is provided between the path  33  and the ground, between the inductor L 34  and the port  32 . 
     The LC circuit  40  includes a port  41  connected to the common port  2 , a port  42  connected to the port  11  of the resonator  10  and the port  21  of the resonator  20 , a path  43  connecting the ports  41  and  42 , inductors IA 1  and L 42 , and capacitors C 41  and C 42 . The inductors IA 1  and L 42  are provided in this order in series in the path  43  from the port  41  side. The capacitor C 41  is provided between a connection point of the inductors IA 1  and L 42  and the ground. The capacitor C 42  is connected in parallel with the inductor L 42 . 
     The first signal of the frequency within the first passband passes selectively through the path  43  of the LC circuit  40  and the path  13  of the resonator  10 . The second signal of the frequency within the second passband passes selectively through the path  33  of the resonator  30 . The third signal of the frequency within the third passband passes selectively through the path  43  of the LC circuit  40  and the path  23  of the resonator  20 . In such a manner, the electronic component  1  separates the first, second, and third signals. 
     Next, other configurations of the electronic component  1  will be described with reference to  FIGS. 2 to 5 .  FIG. 2  is a perspective view showing the appearance of the electronic component  1 .  FIG. 3  is a cross-sectional view of the electronic component  1 .  FIG. 4  is an internal perspective view of a stack of the electronic component  1 .  FIG. 5  is an internal plan view of the stack of the electronic component  1 . 
     The electronic component  1  further includes a stack  50  including a plurality of dielectric layers and a plurality of conductor layers stacked together, and a shield  80  that is formed of a conductor and covers a part of the surface of the stack  50 . The stack  50  is intended to integrate the common port  2 , the signal ports  3  to  5 , the resonators  10 ,  20 , and  30 , and the LC circuit  40 . The resonators  10 ,  20 , and  30  and the LC circuit  40  are formed using the plurality of conductor layers. 
     The stack  50  has a bottom surface  50 A and a top surface  50 B located at both ends in a stacking direction T of the plurality of dielectric layers, and four side surfaces  50 C to  50 F connecting the bottom surface  50 A and the top surface  50 B. The side surfaces  50 C and  50 D are opposite to each other. The side surfaces  50 E and  50 F are opposite to each other. The side surfaces  50 C to  50 F are perpendicular to the top surface  50 B and the bottom surface  50 A. 
     The electronic component  1  further includes terminals  111 ,  112 ,  113 ,  114 ,  115 ,  116 ,  117 ,  118 , and  119  provided on the bottom surface  50 A of the stack  50 . The terminal  111  is located at the center of the bottom surface  50 A. The terminal  112  is located near the corner where the bottom surface  50 A and the side surfaces  50 C and  50 F make contact. The terminal  113  is located near the corner where the bottom surface  50 A and the side surfaces  50 C and  50 E make contact. The terminal  114  is located near the corner where the bottom surface  50 A and the side surfaces  50 D and  50 E make contact. The terminal  115  is located near the corner where the bottom surface  50 A and the side surfaces  50 D and  50 F make contact. The terminal  116  is located between the terminals  112  and  113 . The terminal  117  is located between the terminals  113  and  114 . The terminal  118  is located between the terminals  114  and  115 . The terminal  119  is located between the terminals  112  and  115 . 
     The terminal  112  corresponds to the common port  2 , the terminal  113  to the signal port  3 , the terminal  114  to the signal port  4 , and the terminal  115  to the signal port  5 . The common port  2  and the signal ports  3  to  5  are thus provided on the bottom surface  50 A of the stack  50 . Each of the terminals  111 ,  116  to  119  is connected to the ground. The shield  80  is electrically connected to the terminals  111 ,  116  to  119 . 
     The shield  80  entirely covers the top surface  50 B and the four side surfaces  50 C to  50 F of the stack  50 . The shield  80  includes five portions: one covering the top surface  50 B of the stack  50 ; the other four covering the four side surfaces  50 C to  50 F of the stack  50 . Of the five portions of the shield  80 , the one portion covering the top surface  50 B of the stack  50  will be referred to as the top covering portion  80 B, and the four portions covering the side surfaces  50 C to  50 F of the stack  50  will be referred to as the side covering portions  80 C to  80 F. The shield  80  may include a plurality of metal layers stacked together. 
     Reference is now made to  FIG. 6A  to  FIG. 14  to describe an example of the dielectric layers constituting the stack  50  and the configuration of a plurality of conductor layers formed on the dielectric layers and a plurality of through holes formed in the dielectric layers. In this example, the stack  50  includes twenty-nine dielectric layers stacked together. The twenty-nine dielectric layers will be referred to as a first to a twenty-ninth dielectric layer in the order from bottom to top. The first to twenty-ninth dielectric layers are denoted by reference numerals  51  to  79 , respectively. 
     In  FIG. 6A  to  FIG. 13C , each circle represents a through hole. The dielectric layers  51  to  74  each have a plurality of through holes. Each of the plurality of through holes is connected to a conductor layer or another through hole. 
       FIG. 6A  shows the patterned surface of the first dielectric layer  51 . The terminals  111  to  119  are formed on the patterned surface of the dielectric layer  51 . 
       FIG. 6B  shows the patterned surface of the second dielectric layer  52 . Conductor layers  521 ,  522 ,  523 ,  524 ,  525 , and  526  are formed on the patterned surface of the dielectric layer  52 . The conductor layer  523  is connected to the conductor layer  521 . The conductor layer  525  is connected to the conductor layer  524 . The conductor layer  526  is connected to the conductor layer  525 . 
       FIG. 6C  shows the patterned surface of the third dielectric layer  53 . Conductor layers  531 ,  532 ,  533 ,  534 ,  535 ,  536 ,  537 , and  538  are formed on the patterned surface of the dielectric layer  53 . The conductor layer  532  is connected to the conductor layer  531 . 
       FIG. 7A  shows the patterned surface of the fourth dielectric layer  54 . Conductor layers  541 ,  542 ,  543 ,  544 ,  545 ,  546 ,  547 ,  548 , and  549  are formed on the patterned surface of the dielectric layer  54 . The conductor layer  545  is connected to the conductor layer  542 . The conductor layer  544  is connected to the conductor layer  543 . The conductor layer  547  is connected to the conductor layer  546 . 
       FIG. 7B  shows the patterned surface of the fifth dielectric layer  55 . Conductor layers  551 ,  552 ,  553 ,  554 , and  555  are formed on the patterned surface of the dielectric layer  55 . The conductor layer  552  is connected to the conductor layer  551 . 
       FIG. 7C  shows the patterned surface of the sixth dielectric layer  56 . Conductor layers  561 ,  562 ,  563 ,  564 ,  565 , and  566  are formed on the patterned surface of the dielectric layer  56 . The conductor layer  566  is connected to the conductor layer  565 . 
       FIG. 8A  shows the patterned surface of the seventh dielectric layer  57 . Conductor layers  571 ,  572 ,  573 ,  574 , and  575  are formed on the patterned surface of the dielectric layer  57 . The conductor layer  572  is connected to the conductor layer  571 . 
       FIG. 8B  shows the patterned surface of the eighth dielectric layer  58 . Conductor layers  581 ,  582 , and  583  are formed on the patterned surface of the dielectric layer  58 . 
       FIG. 8C  shows the patterned surface of the ninth dielectric layer  59 . Conductor layers  591 ,  592 ,  593 ,  594 , and  595  are formed on the patterned surface of the dielectric layer  59 . The conductor layer  593  is connected to the side covering portion  80 E of the shield  80 . The conductor layer  594  is connected to the side covering portion  80 C of the shield  80 . The conductor layer  595  is connected to the side covering portion  80 F of the shield  80 . 
       FIG. 9A  shows the patterned surface of the tenth dielectric layer  60 . Conductor layers  601  and  602  are formed on the patterned surface of the dielectric layer  60 . The conductor layer  602  is connected to the side covering portion  80 D of the shield  80 . 
       FIG. 9B  shows the patterned surface of the eleventh dielectric layer  61 . Conductor layers  611  and  612  are formed on the patterned surface of the dielectric layer  61 . 
       FIG. 9C  shows the patterned surface of the twelfth dielectric layer  62 . Conductor layers  621 ,  622 , and  623  are formed on the patterned surface of the dielectric layer  62 . 
       FIG. 10A  shows the patterned surface of the thirteenth dielectric layer  63 . Conductor layer  631  is formed on the patterned surface of the dielectric layer  63 . 
       FIG. 10B  shows the patterned surface of the fourteenth dielectric layer  64 . Conductor layers  641 ,  642 ,  643 , and  644  are formed on the patterned surface of the dielectric layer  64 . 
       FIG. 10C  shows the patterned surface of the fifteenth dielectric layer  65 . Conductor layers  651 ,  652 ,  653 , and  654  are formed on the patterned surface of the dielectric layer  65 . 
       FIG. 11A  shows the patterned surface of the sixteenth dielectric layer  66 . Conductor layers  661 ,  662 ,  663 ,  664 , and  665  are formed on the patterned surface of the dielectric layer  66 . 
       FIG. 11B  shows the patterned surface of the seventeenth dielectric layer  67 . Conductor layers  671 ,  672 ,  673 ,  674 , and  675  are formed on the patterned surface of the dielectric layer  67 . 
       FIG. 11C  shows the patterned surface of the eighteenth dielectric layer  68 . Conductor layers  681 ,  682 ,  683 ,  684 ,  685 , and  686  are formed on the patterned surface of the dielectric layer  68 . 
       FIG. 12A  shows the patterned surface of the nineteenth dielectric layer  69 . Conductor layers  691 ,  692 ,  693 ,  694 ,  695 , and  696  are formed on the patterned surface of the dielectric layer  69 . 
       FIG. 12B  shows the patterned surface of the twentieth dielectric layer  70 . Conductor layers  701 ,  702 ,  703 ,  704 ,  705 ,  706 , and  707  are formed on the patterned surface of the dielectric layer  70 . 
       FIG. 12C  shows the patterned surface of the twenty-first dielectric layer  71 . Conductor layers  711 ,  712 ,  713 ,  714 ,  715 ,  716 , and  717  are formed on the patterned surface of the dielectric layer  71 . 
       FIG. 13A  shows the patterned surface of the twenty-second dielectric layer  72 . Conductor layers  721 ,  722 ,  723 ,  724 ,  725 ,  726 , and  727  are formed on the patterned surface of the dielectric layer  72 . The conductor layer  727  is connected to the conductor layer  726 . 
       FIG. 13B  shows the patterned surface of the twenty-third dielectric layer  73 . Conductor layers  731 ,  732 ,  733 ,  734 ,  735 ,  736 , and  737  are formed on the patterned surface of the dielectric layer  73 . The conductor layer  737  is connected to the conductor layer  736 . 
       FIG. 13C  shows the patterned surface of the twenty-fourth dielectric layer  74 . Conductor layers  741  and  742  are formed on the patterned surface of the dielectric layer  74 . 
       FIG. 14A  shows the patterned surface of the twenty-fifth dielectric layer  75 . Conductor layers  751  and  752  are formed on the patterned surface of the dielectric layer  75 . 
       FIG. 14B  shows the patterned surface of each of the twenty-sixth to twenty-eighth dielectric layers  76  to  78 . No conductor layers or through holes are formed on/in each of the dielectric layers  76  to  78 . 
       FIG. 14C  shows the patterned surface of the twenty-ninth dielectric layer  79 . A mark  791  made of a conductor layer is formed on a marked surface of the dielectric layer  79  opposite to the patterned surface. 
     The stack  50  shown in  FIG. 2  to  FIG. 5  is formed by stacking the first to twenty-ninth dielectric layers  51  to  79  such that the patterned surface of the first dielectric layer  51  also serves as the bottom surface  50 A of the stack  50 , while the marked surface of the twenty-ninth dielectric layer  79  and the top surface of the mark  791  constitute the top surface  50 B of the stack  50 . 
     When the first to twenty-ninth dielectric layers  51  to  79  are stacked, each of the plurality of through holes shown in  FIGS. 6A to 13C  is connected to a conductor layer overlapping in the stacking direction T or to another through hole overlapping in the stacking direction T. Of the plurality of through holes shown in  FIGS. 6A to 13C , the ones located within a terminal or a conductor layer are connected to the terminal or conductor layer. 
     Correspondences between the circuit components of the electronic component  1  shown in  FIG. 1  and the internal components of the stack  50  shown in  FIG. 6A  to  FIG. 14C  will now be described. The components of the resonator  10  will initially be described. The inductor L 11  is composed of the conductor layers  641 ,  651 ,  661 ,  671 ,  681 ,  691 ,  701 ,  711 ,  721 ,  731 ,  741 , and  751  shown in  FIG. 10B  to  FIG. 14A  and the through holes connected to those conductor layers. 
     The inductor L 12  is composed of the conductor layers  683 ,  693 ,  703 ,  713 ,  723 , and  733  shown in  FIG. 11C  to  FIG. 13B  and the through holes connected to those conductor layers. 
     The capacitor C 11  is composed of the conductor layers  521 ,  531 ,  541 ,  551 ,  561 , and  571  shown in  FIG. 6B  to  FIG. 8A  and the dielectric layers  52  to  56  each interposed between two of those conductor layers. 
     The capacitor C 12  is composed of the conductor layers  522 ,  532 ,  542 ,  552 ,  562 ,  572 , and  581  shown in  FIG. 6B  to  FIG. 8B  and the dielectric layers  52  to  57  each interposed between two of those conductor layers. 
     The capacitor C 13  is composed of the conductor layers  523  and  543  shown in  FIG. 6B  and  FIG. 7A  and the dielectric layers  52  and  53  each interposed between two of those conductor layers. 
     Next, the components of the resonator  20  will be described. The inductor L 21  is composed of the conductor layers  642 ,  652 ,  662 ,  672 ,  682 ,  692 ,  702 ,  712 ,  722 ,  732 ,  742 , and  752  shown in  FIG. 10B  to  FIG. 14A  and the through holes connected to those conductor layers. 
     The capacitor C 21  is composed of the conductor layers  544  and  545  shown in  FIG. 7A  and  FIG. 7B  and the dielectric layer  54  interposed between two of those conductor layers. 
     The capacitor C 22  is composed of the conductor layers  553 ,  563 ,  573 , and  582  shown in  FIG. 7B  to  FIG. 8B  and the dielectric layers  55  to  57  each interposed between two of those conductor layers. 
     The capacitor C 23  is composed of the conductor layers  533  and  543  shown in  FIG. 6C  and  FIG. 7A  and the dielectric layer  53  interposed between two of those conductor layers. 
     Next, the components of the resonator  30  will be described. The inductor L 31  is composed of the conductor layers  664 ,  674 ,  684 ,  694 ,  704 ,  714 ,  724 , and  734  shown in  FIG. 11A  to  FIG. 13B  and the through holes connected to those conductor layers. 
     The inductor L 32  is composed of the conductor layers  591 ,  601 ,  611 , and  621  shown in  FIG. 8C  to  FIG. 9C  and the through holes connected to those conductor layers. 
     The inductor L 33  is composed of the conductor layers  644 ,  654 ,  665 ,  675 ,  685 ,  695 ,  705 ,  715 ,  725 , and  735  shown in  FIG. 10B  to  FIG. 13B  and the through holes connected to those conductor layers. 
     The inductor L 34  is composed of the conductor layers  564 ,  574 ,  583 , and  592  shown in  FIG. 7C  to  FIG. 8C  and the through holes connected to those conductor layers. 
     The capacitor C 31  is composed of the conductor layers  555  and  565  shown in  FIG. 7B  and  FIG. 7C  and the dielectric layer  55  interposed between two of those conductor layers. 
     The capacitor C 32  is composed of the conductor layers  546  and  566  shown in  FIG. 7A  and  FIG. 7C  and the dielectric layers  54  and  55  each interposed between two of those conductor layers. 
     The capacitor C 33  is composed of the conductor layers  535 ,  547 , and  555  shown in  FIG. 6C  to  FIG. 7B  and the dielectric layers  53  and  54  each interposed between two of those conductor layers. 
     The capacitor C 34  is composed of the conductor layers  536  and  546  shown in  FIG. 6C  and  FIG. 7A  and the dielectric layer  53  interposed between two of those conductor layers. 
     The capacitor C 35  is composed of the conductor layers  525 ,  537 , and  548  shown in  FIG. 6B  to  FIG. 7A  and the dielectric layers  52  and  53  each interposed between two of those conductor layers. 
     The capacitor C 36  is composed of the conductor layers  538  and  549  shown in  FIG. 6C  and  FIG. 7A  and the dielectric layer  53  interposed between two of those conductor layers. 
     The capacitor C 37  is composed of the conductor layers  526  and  538  shown in  FIG. 6B  and  FIG. 6C  and the dielectric layer  52  interposed between two of those conductor layers. 
     Next, the components of the LC circuit  40  will be described. The inductor L 41  is composed of the conductor layers  643 ,  653 ,  663 ,  673 ,  686 ,  696 ,  706 ,  716 ,  726 , and  736  shown in  FIG. 10B  to  FIG. 13B  and the through holes connected to those conductor layers. 
     The inductor L 42  is composed of the conductor layers  707 ,  701 ,  727 , and  737  shown in  FIG. 12B  to  FIG. 13B  and the through holes connected to those conductor layers. 
     The capacitor C 41  is composed of the conductor layers  524  and  534  shown in  FIG. 6B  and  FIG. 6C  and the dielectric layer  52  interposed between two of those conductor layers. 
     The capacitor C 42  is composed of the conductor layers  534  and  544  shown in  FIG. 6C  and  FIG. 7A  and the dielectric layer  53  interposed between two of those conductor layers. 
     Next, a connection relationship between the shield  80  and the internal components of the stack  50  will be described. The side covering portion  80 C of the shield  80  is connected to the terminals  116  and  117  via the conductor layers  521 ,  523 , and  594  and a plurality of through holes shown in  FIGS. 6A to 8C . The side covering portion  80 D of the shield  80  is connected to the terminals  111 ,  118 , and  119  via the conductor layers  524 ,  525 , and  602  and a plurality of through holes shown in  FIGS. 6A to 9A . The side covering portion  80 E of the shield  80  is connected to the terminals  116  and  117  via the conductor layers  521 ,  523 ,  561 , and  593  and a plurality of through holes shown in  FIGS. 6A to 8C . The side covering portion  80 F of the shield  80  is connected to the terminals  111 ,  118 , and  119  via the conductor layers  524 ,  525 , and  595  and a plurality of through holes shown in  FIGS. 6A to 8C . 
     Next, structural features of the electronic component  1  according to the present embodiment will be described with reference to  FIGS. 3 to 5 . The shield  80  includes a specific portion opposed to both the resonators  10  and  30 . The distance between the resonator  30  and the specific portion is greater than the distance between the resonator  10  and the specific portion. 
     The specific portion will now be described in concrete terms. The side covering portion  80 C of the shield  80  corresponds to the specific portion. The inductor L 12  and the capacitor C 12  of the resonator  10  are opposed to the side covering portion  80 C. In the present embodiment, in particular, the distances between the conductor layers  683 ,  693 ,  703 ,  713 ,  723 , and  733 , constituting the inductor L 12 , and the side covering portion  80 C are the same as those between the conductor layers  522 ,  542 ,  562 , and  581 , constituting the capacitor C 12 , and the side covering portion  80 C. The inductor L 31  and the capacitor C 33  of the resonator  30  are also opposed to the side covering portion  80 C. The distances between the conductor layers  664 ,  674 ,  704 , and  714 , constituting the inductor L 31 , and the side covering portion  80 C are greater than the distance between the conductor layer  535 , constituting the capacitor C 33 , and the side covering portion  80 C. 
     As shown in  FIG. 5 , the distance between the inductor L 31  (conductor layer  714 ) of the resonator  30  and the side covering portion  80 C is greater than the distance between the inductor L 12  (conductor layer  733 ) of the resonator  10  and the side covering portion  80 C. The distance between the resonator  30  and the side covering portion  80 C is thus greater than the distance between the resonator  10  and the side covering portion  80 C. As can be seen in  FIGS. 6B to 8B , the distance between the capacitor C 33  (conductor layer  535 ) of the resonator  30  and the side covering portion  80 C is greater than the distance between the capacitor C 12  (conductor layers  522 ,  542 ,  562 , and  581 ) of the resonator  10  and the side covering portion  80 C. 
     The top covering portion  80 B of the shield  80  also corresponds to the specific portion. The conductor layer  751 , constituting the inductor L 11  of the resonator  10 , is opposed to the top covering portion  80 B. The conductor layer  734 , constituting the inductor L 31  of the resonator  30 , and the conductor layer  735 , constituting the inductor L  33  of the resonator  30 , are opposed to the top covering portion  80 B. As shown in  FIG. 3 , the distance between the inductors L 31  and L 33  (conductor layers  734  and  735 ) of the resonator  30  and the top covering portion  80 B is greater than the distance between the inductor L 11  (conductor layer  751 ) of the resonator  10  and the top covering portion  80 B. The distance between the resonator  30  and the top covering portion  80 B is thus greater than the distance between the resonator  10  and the top covering portion  80 B. 
     The top covering portion  80 B of the shield  80  is also opposed to the resonator  20 . The conductor layer  752 , constituting the inductor L 21  of the resonator  20 , is opposed to the top covering portion  80 B. As shown in  FIG. 3 , the distance between the inductors L 31  and L 33  (conductor layers  734  and  735 ) of the resonator  30  and the top covering portion  80 B is greater than the distance between the inductor L 21  (conductor layer  752 ) of the resonator  20  and the top covering portion  80 B. The distance between the resonator  30  and the top covering portion  80 B is thus greater than the distance between the resonator  20  and the top covering portion  80 B. 
     The side covering portion  80 E of the shield  80  is opposed to both the resonators  10  and  20 . The inductor L 12  and the capacitors C 11  and C 12  of the resonator  10  are opposed to the side covering portion  80 E. In the present embodiment, in particular, the distances between the conductor layers  683 ,  693 ,  703 ,  713 ,  723 , and  733  constituting the inductor L 12  and the side covering portion  80 E, the distances between the conductor layers  531 ,  551 , and  571  constituting the capacitor C 11  and the side covering portion  80 E, and the distances between the conductor layers  522 ,  542 ,  562 , and  581  constituting the capacitor C 12  and the side covering portion  80 E are equal to each other. The inductor L 21  and the capacitors C 22  and C 23  of the resonator  20  are also opposed to the side covering portion  80 E. The distances between the conductor layers  642 ,  652 ,  662 ,  672 ,  682 ,  692 ,  722 ,  732 ,  742 , and  752 , constituting the inductor L 21 , and the side covering portion  80 E are greater than the distance between the conductor layers  533  and  553 , constituting the capacitors C 22  and C 23 , and the side covering portion  80 E. 
     As shown in  FIG. 5 , the distance between the inductor L 21  (conductor layer  752 ) of the resonator  20  and the side covering portion  80 E is greater than the distance between the inductor L 12  (conductor layer  733 ) of the resonator  10  and the side covering portion  80 E. As can be seen in  FIGS. 6B to 8B , the distance between the capacitors C 22  and C 23  (conductor layers  533  and  553 ) of the resonator  20  and the side covering portion  80 E is greater than the distance between the capacitors C 11  and C 12  (conductor layers  522 ,  531 ,  542 ,  551 ,  562 ,  571  and  581 ) of the resonator  10  and the side covering portion  80 C. The distance between the resonator  20  and the side covering portion  80 E is thus greater than the distance between the resonator  10  and the side covering portion  80 E. 
     The side covering portion  80 C and the top covering portion  80 B of the shield  80  is also opposed to the LC circuit  40 . The conductor layers  643 ,  653 ,  686 ,  696 ,  726 , and  736 , constituting the inductor L 41  of the LC circuit  40 , is opposed to the side covering portion  80 C. As shown in  FIG. 5 , the distance between the inductor L 41  (conductor layer  736 ) of the LC circuit  40  and the side covering portion  80 C is greater than the distance between the inductor L 12  (conductor layer  733 ) of the resonator  10  and the side covering portion  80 C. The distance between the LC circuit  40  and the side covering portion  80 C is thus greater than the distance between the resonator  10  and the side covering portion  80 C. 
     The conductor layer  736 , constituting the inductor L 41  of the LC circuit  40 , and the conductor layer  737 , constituting the inductor L 42  of the LC circuit  40 , are opposed to the top covering portion  80 B. As shown in  FIG. 3 , the distance between the inductors L 41  and L 42  (conductor layers  736  and  737 ) of the LC circuit  40  and the top covering portion  80 B is greater than the distance between the inductor L 11  (conductor layer  751 ) of the resonator  10  and the top covering portion  80 B. The distance between the LC circuit  40  and the top covering portion  80 B is thus greater than the distance between the resonator  10  and the top covering portion  80 B. 
     The specific portion is not limited to the foregoing examples. For example, a part of the top covering portion  80 B or a part of a side covering portion may serve as the specific portion. A plurality of side covering portions may be regarded as a specific portion. 
     Next, an example of the characteristics of the electronic component  1  according to the present embodiment will be described.  FIG. 15  is a characteristic chart showing an example of pass characteristics of the electronic component  1 .  FIG. 16  is a characteristic chart showing an example of reflection characteristics of the electronic component  1 . In  FIGS. 15 and 16 , the horizontal axis indicates the frequency, and the vertical axis indicates the attenuation. In  FIG. 15 , the curve denoted by the reference numeral  81  represents the pass characteristic of the first filter constituted by the resonator  10  provided between the common port  2  and the signal port  3 . The curve denoted by the reference numeral  82  represents the pass characteristic of the third filter constituted by the resonator  20  provided between the common port  2  and the signal port  4 . The curve denoted by the reference numeral  83  represents the pass characteristic of the second filter constituted by the resonator  30  provided between the common port  2  and the signal port  5 . 
     Next, the operation and effects of the electronic component  1  according to the present embodiment will be described. In the present embodiment, the shield  80  covers a part of the surface of the stack  50 . In the present embodiment, in particular, the shield  80  covers the top surface  50 B and the four side surfaces  50 C to  50 F of the stack  50 . Thus, according to the present embodiment, electromagnetic interference between a plurality of electronic components and changes in the characteristics of the electronic component due to a shield case can be prevented. 
     In the present embodiment, the resonators  10 ,  20 , and  30  are integrated with the stack  50 . The resonators  10 ,  20 , and  30  are formed using the plurality of conductor layers included in the stack  50 . The resonator  10  is provided in the signal path through which the first signal of the frequency within the first passband passes. The resonator  20  is provided in the signal path through which the third signal of the frequency within the third passband passes. The resonator  30  is provided in the signal path through which the second signal of the frequency within the second passband passes. 
     In the present embodiment, the shield  80  is provided on the surface of the stack  50 . The components of each of the resonators  10 ,  20 , and  30  can thus be capacitively coupled with the shield  80 . The resonators  10  and  30  will now be compared. The resonator  30  is provided in the signal path of a higher passband than the resonator  10 . The resonator  30  is thus susceptible to the capacitive coupling and impedance matching will be difficult compared to the resonator  10 . 
     As described above, in the present embodiment, the distance between the resonator  30  and the specific portion of the shield  80  is greater than the distance between the resonator  10  and the specific portion of the shield  80 . Therefore, according to the present embodiment, the effect of the capacitive coupling with the shield  80  on the resonator  30  can thereby be reduced to facilitate impedance matching. 
     Similarly, the resonator  20  is provided in the signal path of a higher passband than the resonator  10 . In the present embodiment, the distance between the resonator  20  and the specific portion of the shield  80  is greater than the distance between the resonator  10  and the specific portion of the shield  80 . Therefore, according to the present embodiment, the effect of the capacitive coupling with the shield  80  on the resonator  20  can thereby be reduced to facilitate impedance matching. 
     The resonators  20  and  30  will now be compared. The resonator  30  is provided in the signal path of a higher passband than the resonator  20 . As described above, in the present embodiment, the distance between the resonator  30  and the specific portion of the shield  80  is greater than the distance between the resonator  20  and the specific portion of the shield  80 . 
     Moreover, in the present embodiment, the LC circuit  40  is provided between the common port  2  and the resonators  10  and  20 . The LC circuit  40  includes at least one element formed by using a plurality of conductor layers included in the stack  50 . The at least one element of the LC circuit  40  can also be capacitively coupled with the shield  80 . Changes in the impedance of the LC circuit  40  have a higher impact on the resonator  30  than on the resonators  10  and  20 . As described above, in the present embodiment, the distance between the LC circuit  40  and the specific portion of the shield  80  is greater than the distance between the resonator  10  and the specific portion of the shield  80 . As a result, according to the present embodiment, the impact of changes in the impedance of the LC circuit  40  on the resonator  30  can thereby be reduced. 
     As described above, according to the present embodiment, desired characteristics can be achieved while preventing the occurrence of electromagnetic malfunctions due to high density packaging. 
     In the present embodiment, the distance between the inductor L 31  or L 33  of the resonator  30  and the specific portion (top covering portion  80 B or side covering portion  80 C) of the shield  80  is the distance between the resonator  30  and the specific portion of the shield  80 . However, not only the inductors and capacitors but the conductor layers and through holes constituting the path  33  of the resonator  30  can be capacitively coupled with the shield  80  as well. If a conductor layer or through hole constituting a part of the path  33  of the resonator  30  is closer to the specific portion of the shield  80  than the elements included in the resonator  30  such as the inductors L 31  and L 33 , the effect of the capacitive coupling with the shield  80  on the resonator  30  can be reduced by increasing the distance between the conductor layer or through hole and the specific portion of the shield  80 . 
     The foregoing description of the path  33  of the resonator  30  also applies to the path  23  of the resonator  20  and the path  43  of the LC circuit  40 . 
     In the present embodiment, the distance between the resonator  30  and the shield  80  is increased without increasing the distance between the resonator  10  and the shield  80 . Thus, according to the present embodiment, the electronic component  1  can be miniaturized compared to the case where the distance between the resonator  10  and the shield  80  is the same as the distance between the resonator  30  and the shield  80 . 
     Next, the result of a simulation examining the effect of the shield  80  on the characteristics of the electronic component  1  will be described. The simulation used a model of a practical example corresponding to the electronic component  1  according to the present embodiment and a model of a comparative example corresponding to an electronic component according to the comparative example. In the simulation, the model of the practical example was created so that the distance from each of the inductors L 32 , L 33 , and L 34  of the resonator  30  and the inductors L 41  and L 42  of the LC circuit  40  to the top covering portion  80 B of the shield  80  in the electronic component  1  fell within the range of 150 to 220 μm. 
     The electronic component of the comparative example had basically the same configuration as that of the electronic component  1  according to the present embodiment. In the simulation, the model of the comparative example was created so that the distance from each of the inductors L 32 , L 33 , and L 34  of the resonator  30  and the inductors L 41  and L 42  of the LC circuit  40  to the top covering portion  80 B of the shield  80  in the electronic component of the comparative example was 30 μm. 
     In the simulation, the passband of the second filter constituted by the resonator  30  was 3300 MHz or more and 5000 MHz or less. The passband of the third filter constituted by the resonator  20  was 1428 MHz or more and 2690 MHz or less. The second filter will hereinafter be referred to also as a high band filter, and the third filter as a middle band filter. 
       FIG. 17  is a characteristic chart showing the insertion loss of the middle band filter (third filter).  FIG. 18  is a characteristic chart showing the return loss of the middle band filter (third filter).  FIG. 19  is a characteristic chart showing the insertion loss of the high band filter (second filter).  FIG. 20  is a characteristic chart showing the return loss of the high band filter (second filter). In  FIGS. 17 to 20 , the horizontal axis indicates the frequency. In  FIGS. 17 and 19 , the vertical axis indicates the insertion loss. In  FIGS. 18 and 20 , the vertical axis indicates the return loss. 
     In  FIG. 17 , the curve denoted by the reference numeral  84  represents the insertion loss of the middle band filter in the model of the practical example. The curve denoted by the reference numeral  85  represents the insertion loss of the middle band filter in the model of the comparative example. In  FIG. 18 , the curve denoted by the reference numeral  86  represents the return loss of the middle band filter in the model of the practical example. The curve denoted by the reference numeral  87  represents the return loss of the middle band filter in the model of the comparative example. In  FIG. 19 , the curve denoted by the reference numeral  88  represents the insertion loss of the high band filter in the model of the practical example. The curve denoted by the reference numeral  89  represents the insertion loss of the high band filter in the model of the comparative example. In  FIG. 20 , the curve denoted by the reference numeral  90  represents the return loss of the high band filter in the model of the practical example. The curve denoted by the reference numeral  91  represents the return loss of the high band filter in the model of the comparative example. 
     As shown in  FIGS. 17 and 19 , both the middle band filter and the high band filter of the model of the comparative example had higher insertion loss than the model of the practical example in the respective passbands. As shown in  FIGS. 18 and 20 , both the middle band filter and the high band filter of the model of the comparative example had lower return loss than the model of the practical example in the respective passbands. The reason why the model of the comparative example had low return loss as described above is that the impedance of the filters in their respective passbands was too low to achieve impedance matching. As a result, the model of the comparative example had high insertion loss. 
     From the result of the simulation, it can be seen that worsening in the characteristics of the high band filter (second filter) can be prevented by locating the inductors L 32 , L 33 , and L 34  of the resonator  30  away from the top covering portion  80 B of the shield  80 . Similarly, it can be seen from the result of the simulation that worsening in the characteristics of the middle band filter (third filter) can be prevented by locating the inductors L 41  and L 42  of the LC circuit  40  away from the top covering portion  80 B of the shield  80 . 
     In the simulation, the distance from each of the resonator  30  and the LC circuit  40  to the top covering portion  80 B of the shield  80  was changed. However, the result of the simulation applies not only to the top covering portion  80 B of the shield  80 , but also to other portions of the shield  80 . More specifically, worsening in the characteristics of the high band filter (second filter) can also be prevented by locating the resonator  30  away from the portions of the shield  80  other than the top covering portion  80 B. Similarly, worsening in the characteristics of the middle band filter (third filter) can also be prevented by locating the LC circuit  40  away from the portions of the shield  80  other than the top covering portion  80 B. 
     The present invention is not limited to the foregoing embodiment, and various modifications may be made thereto. For example, the electronic component according to the present invention may be a diplexer for separating two signals of different frequency bands, or an electronic component that handles a plurality of signals of different frequencies other than a branching filter. 
     The electronic component  1  may include a circuit including one or more inductors instead of the LC circuit  40 . 
     Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. Thus, it is to be understood that, within the scope of the appended claims and equivalents thereof, the invention may be practiced in other embodiments than the foregoing most preferable embodiment.