Patent Publication Number: US-2022238485-A1

Title: Packaged electronic system formed by electrically connected and galvanically isolated dice

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates to a packaged electronic system formed by electrically connected and galvanically isolated dice. 
     Description of the Related Art 
     Electronic systems where the dice are packaged in a package and integrate electronic devices (components and/or circuits) configured to work at very different voltages and to exchange signals with each other. For instance, the electronic systems may be a power-supply system, a digital isolator, a power transistor driving system, a DC-DC converter, or other system where at least one of the devices operates at high voltage (even higher than 10 kV) and/or high power. For these systems, it is known to include measures for maintaining an adequate isolation galvanic between the various devices. 
     In particular, packages dedicated to providing a high isolation level are mainly based upon two approaches:
         two-dice approach, where two dice integrate each a respective “functional” device and a respective (capacitive or inductive) isolation element and the two isolation elements are connected together; and   three-dice approach, comprising an isolation device integrated in a die connected to the two “functional” devices (e.g., two other die).       

     The two-dice approach is shown, for example, in  FIGS. 1 and 2  of the present disclosure. Here a package  5  of resin or other insulating material encloses a system comprising two dice  8 ,  9  integrating a respective electronic circuit  10  and a respective isolation element  11 . For instance, the circuits  10  may be ASICs (Application-Specific Integrated Circuits); alternatively, one or both circuits  10  may integrate individual electronic components and/or be formed by different circuits. 
     The circuits  10  are connected to the respective isolation elements  11  through buried or surface connections, not shown; the isolation elements  11  in the dice  8 ,  9  are connected by connection wires  12 . 
     The dice  8 ,  9  are each fixed to a respective supporting element  15  that is part of a leadframe for connecting different terminals of the circuits  10  to the outside, in a per se known manner. Bonding wires  16  connect the terminals of the circuits  10  to the respective leadframe  15 , and the package  5  embeds the dice  8 ,  9 , the wires  12 ,  16  and part of the leadframe  15  so as to electrically isolate them and protect them from the external environment. 
     The two-dice approach is intrinsically robust as regards parasitic elements, since the connection wires  12  are just a few, are short, and are arranged in a less critical position (downstream of the isolation elements  11 ), but, in some applications, may be far from flexible. In fact, the designer has only a few degrees of freedom in the design of the isolation elements, being constrained to the technologies and platforms for manufacturing the circuits  10 . In particular, with this approach, the designer is not always able to use the most advanced approaches and knowledge and frequently cannot use the same isolation elements when the circuits  10  of the dice  8 ,  9  are manufactured using different technologies. 
     The three-dice approach is shown, for example, in  FIGS. 3 and 4 . Here a package  25  of resin or other insulating material encloses a system formed by two “operative” dice (first and second die  28 ,  29 ). The dice  28 ,  29  integrate each an electronic circuit or component  26  and  27 , respectively, and are fixed to a respective leadframe  22 ,  23 , also here shown in a simplified way. The isolation element, designated by  31 , is integrated in a third die  32  fixed on one of the two leadframes, here on the leadframe  22  carrying the first die  28 . 
     The first circuit  26  is connected to the isolation element  31  through first connection wires  35 , and the second circuit  27  is connected to the isolation element  31  through second connection wires  36 , generally longer than the first connection wires  35 . 
     Bonding wires  38  connect the terminals of the circuits  26 ,  27  to the respective leadframes  22 ,  23 , and the package  25  embeds the dice  28 ,  29 ,  32 , the wires  35 ,  36 ,  38 , and part of the leadframes  22 ,  23 . 
     The three-dice approach is very flexible and enables use of isolation optimized platforms, irrespective of the technology used for the circuits  26 ,  27 . However, this approach has parasitic components due to the first connection wires  35  and, in particular, the second connection wires  36 , which can cause problems of cross-talk, i.e., interference between the signal-transmission channels. 
     Other possibilities for mutually insulating the devices arranged in a single package include arranging high-value capacitances within one or both devices. However, not even these approaches are altogether satisfactory and/or can be applied to all systems. In fact, the provision of shielding coatings cannot be used for wires of small dimensions and is subject to problems of repeatability, so that it is far from effective. The use of high capacitances is not moreover always possible since they cause an increase in power consumption of the system and can reduce the bandwidth usable for the communications. 
     BRIEF SUMMARY 
     The present disclosure provides a solution that overcomes the drawbacks of the conventional packages and structures as discussed above. 
     According to the present disclosure a packaged electronic system is provided. 
     For example, in at least one embodiment, a package electronic system includes a support, the support comprising an insulating organic substrate housing a buried conductive region, the buried conductive region being a floating region and having a first and a second portion mutually spaced; a connection pad on the support; a first die, fixed to the support, the first die having a first main surface carrying a first die contact region capacitively coupled to the first portion of the buried conductive region; a second die, fixed to the support, the second die having a first main surface carrying a second die contact region, capacitively coupled to the second portion of the buried conductive region; a first and second external connection regions mutually spaced; a connection line coupled to the connection pad and to at least one of the first and second external connection regions to couple at least one of the first and second die to at least one of the first and second external connection regions; and a packaging mass enclosing the first die, the second die, the first die contact region, the second die contact region, and, at least partially, the support 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       For a better understanding of the present disclosure, some embodiments thereof are now described, purely by way of non-limiting example, with reference to the attached drawings, wherein: 
         FIG. 1  is a top view, simplified and with the package shown in phantom, of a known system of devices; 
         FIG. 2  is a cross-sectional side view of the system of  FIG. 1 , with the package shown in phantom; 
         FIG. 3  is a top view, simplified and with the package shown in phantom, of another known system of devices; 
         FIG. 4  is a cross-sectional side view of the system of  FIG. 3 , with the package shown in phantom; 
         FIG. 5A  is a cross-sectional side view of an embodiment of the present system of devices, with the package shown in phantom; 
         FIG. 5B  shows an enlarged detail of  FIG. 5A ; 
         FIG. 6  is a cross-sectional side view of an implementation of a portion of the present system of devices, at an enlarged scale; 
         FIG. 7  is a perspective view of an implementation of a part of the present system of devices, at an enlarged scale; 
         FIG. 8  shows the layout of an implementation of a part of the present system of devices; 
         FIG. 9  is a cross-sectional side view of another embodiment of the present system of devices, with the package shown in phantom; 
         FIG. 10  is a cross-sectional side view of a different embodiment of the present system of devices, with the package shown in phantom; 
         FIG. 11  is a cross-sectional side view of yet another embodiment of the present system of devices, with the package shown in phantom; and 
         FIG. 12  is a cross-sectional side view of a different embodiment of the present system of devices, with the package shown in phantom. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, reference will be made to a system formed by two dice, integrating each an ASIC (Application-Specific Integrated Circuit), but the disclosure applies to electronic devices of any type, whether single components or more complex circuits, operating at different voltages, even having a very different value, in common mode. 
       FIG. 5A  shows a system  50  comprising two dice  51 ,  52  integrating each an own device  53 ,  54 . The devices  53 ,  54  are here both ASICs, as indicated above. The two dice are spaced apart from each other by a distance D 1  as shown in  FIG. 5A . The distance D 1  extends between respective sidewalls of the first die  51  and the second die  52 . 
     The dice  51 ,  52  are both fixed to a support  55 . The support  55  has, for example, a parallelepipedal shape having a first and a second main face  55 A,  55 B (see also the detail of  FIG. 5B ). The first and second main faces  55 A,  55 B may be referred to as surfaces (e.g., a first surface, a second surface, a first main surface, a second main surface, etc.). The first and second main faces  55 A,  55 B are opposite to each other such that the first main face  55 A faces away from the second main face  55   b  and vice versa. The first and second main faces  55 A,  55 B here extend parallel to a plane XY of a Cartesian coordinate system XYZ; the support  55  moreover has a height (parallel to a third axis Z of the Cartesian coordinate system XYZ) that is smaller than the width and length (parallel to a first axis X and a second axis Y, respectively, of the Cartesian coordinate system XYZ). The support  55  may be referred to as an electrical connection element, an electrical connection structure, a capacitive electrical connection element, a capacitive electrical connection structure, or some other reference to the support  55  being configured to provide electrical connections such as capacitive electrical connections within embodiments of the systems, packages, or devices of the present disclosure. 
     The support  55  is an organic support, generally of insulating material. The support may house inside a buried conductive region  56 , which may be readily seen in  FIGS. 5A and 5B  of the present disclosure. The buried conductive region  56  is completely surrounded by the insulating material of the support  55  so that there are no physical conductive connection paths with other parts of the system  50  (in other words, the buried conductive region  56  is floating). 
     For instance, the support  55  may be formed by a printed-circuit board (PCB). According to one embodiment, the support  55  is formed by a multilayer including a sequence of conductive layers, typically of metal, and by insulating layers, for example of organic plastic, and one of the conductive layers forms the buried conductive region  56 , as described more fully hereinafter with reference to  FIG. 6 . 
     The buried conductive region  56  extends for a majority of the length of the support  55  (parallel to the first axis X); in particular, in the embodiment shown, it extends as far as underneath the dice  51 ,  52 . In other words, the dice  51  overlap the buried conductive region  56  based on the orientation as shown in  FIG. 5A . 
     Contact structures  57 A- 57 D on the first face  55 A of support  55  extend from the support  55  to the dice  51 ,  52  to form electrical connections to the dice  51 ,  52 . For example, electrically conductive components within the dice  51 ,  52  are coupled to conductive components in the support  55  by the contact structures  57 A- 57 D, respectively. 
     The contact structures  57 A- 57 D are here formed by a bottom portion  65 , for example formed by a support pad region, arranged on the first face  55 A of the support  55 ; an intermediate portion  66 , forming a bump region, here arranged on the bottom portion  65 ; and a top portion  67 , for example formed by a die pad region, here arranged on the intermediate portion  66  and formed, from example, by respective top metal layers of the dice  51 ,  52 , in a per se known manner. The bottom portion  65  may be referred to as a lower portion or some other reference to the bottom portion  65  at the first face  55 A of the support  55 . The intermediate portion  66  may be referred to as a central portion, a middle portion, or some other reference to the intermediate portion  66  between the bottom portion  65  and the top portion  67 , respectively. The top portion  67  may be referred to as an upper portion or some other reference to the top portion  67  at a respective surface of one of the dice  51 ,  52  that faces towards the first face  55 A of the support  55 . The bottom portion  65 , the intermediate portion  66 , and the top portion  67  may be referred together as a standoff. 
     The top portions  67  of the contact structures  57 A- 57 D are electrically connected to the electrical components of the devices  53 ,  54 , in a known way. 
     Two contact structures, referred to hereinafter as first and second contact structures  57 A,  57 B, connect the first die  51  to the support  55 , and two other contact structures, designated hereinafter as third and fourth contact structures  57 C,  57 D, connect the second die  52  to the support  55 . 
     In particular, here, the bottom portions  65  of the second and third contact structures  57 B,  57 C extend vertically on a respective longitudinal end of the buried conductive region  56  and are thus capacitively coupled thereto. Consequently, in this embodiment the bottom portions  65  of the second and third contact structures  57 B,  57 C form first plates of capacitive elements having a common counterplate formed by the buried conductive region  56 . In this embodiment, then, the bottom portions  65  are also referred to as first plates  65 , and the buried conductive region  56  is also referred to as common floating plate  56 . 
     In other words, a first capacitor  70  is formed between the second contact structure  57 B and the buried conductive region  56 , and a second capacitor  71  is formed between the third contact structure  57 C and the buried conductive region  56 . The first and second capacitors  70 ,  71  are arranged in series to each other through the buried conductive region  56 , thereby providing a galvanic-coupling structure  73  between the first and second dice  51 ,  52 , as discussed in detail hereinafter. 
     The first and fourth contact structures  57 A,  57 D, (as well as other possible contact structures, not shown) connect the respective dice  51 ,  52  electrically to further support pad regions on the support  55 , in a way not shown but known to the person skilled in the art. 
     In  FIG. 5A , a first and a second external connection region  60 ,  61  are fixed to the second main face  55 B of the support  55 . The first and second external connection regions  60 ,  61  may be referred to as external contact regions. 
     The external connection regions  60 ,  61  here implement an LGA (Land Grid Array) connection scheme and form part, in a known way, of a leadframe formed by distinct external connection regions, electrically isolated from each other, which enable electrical connection of the system  50  to the outside (e.g., external to the system  50 ). In particular, the shown external connection regions  60 ,  61  are configured so as to be able to work at voltages very different from each other and/or from operating voltages of one or both of the devices  53 ,  54 , even up to 10 kV. To this end, the external connection regions  60 ,  61  are spaced apart by a distance D 2  that extends between respective sidewalls of the external connection regions  60 ,  61 , and, in this embodiment, the external connection regions  60 ,  61  are fixed to the support  55  so as not to vertically overlap the buried conductive region  56 . 
     In  FIG. 5A , a further pad region  75  extends on the first face  55 A of the support  55 . The further pad region  75  may be provided in the same layer as the first plates  65 , in a way known to the person skilled in the art, and is connected to the second external connection region  61  by an electrical connection wire  76 . The first plates  65  may be coupled to the pad region  75 . 
     A packaging mass  77 , of resin or other insulating material, encloses the dice  51 ,  52 , the support  55 , the electrical connection wire  76 , and a most of the external connection regions  60 ,  61 . The packaging mass  77  may be an encapsulant, a molding compound, a epoxy, a resin, or some other type of material for encasing the various components of the systems, packages, or devices of the present disclosure. 
     In practice, in the system  50  of  FIG. 5A , the capacitors  70 ,  71  provide a galvanic transmission channel between the devices  53 ,  54  enabling transmission of common mode signals between (e.g., to and from) the devices  53 ,  54 . 
     This channel can be used as single transmission channel, according to the devices  53 ,  54 , the specific exchanged signals, and the design choices. Alternatively, the system  50  may include a plurality of such channels, each for a respective signal to be exchanged and/or a transmission direction, as discussed in detail hereinafter. 
     In the system  50  of  FIG. 5A , to obtain the isolation, and according to the specific operating voltages, some distance ratios are important, as discussed hereinafter, based on the first die  51  may operate at a much higher voltage than the first external connection region  60 . 
     In particular, with reference to  FIGS. 5A and 5B , the distance D 2  between the external connection regions  60 ,  61  is chosen to be greater than the distance D 1  between the dice  51 ,  52 . 
     Furthermore, a distance T 1  ( FIG. 5B ) between the second contact structure  57 B and the buried conductive region  56  and a distance T 2  between the buried conductive region  56  and the first external connection region  60  are chosen, to take into account the isolation characteristics of the material of the support  55  and other possible criteria known to the designer. For instance, if the material of the insulating layers forming the support  55  is the same, with the same dielectric strength, the distances T 1  and T 2  may be equal (T 1 =T 2 ). Vice versa, if the bottom portion (in  FIG. 5B ) of the support  55  is of a material able to withstand higher electrical fields than the material interposed between the buried conductive region  56  and the first plate  65  (bottom portion of the second contact structure  57 B), T 1  may be higher than T 2  (T 1 &gt;T 2 ). 
     Similar considerations may be applied to the distance between the third contact structures  57 C and the buried conductive region  56  and to the distance between the buried conductive region  56  and the second external connection region  61 , in case of large voltage differences. 
       FIG. 6  shows a possible implementation of the support  55 . 
     In detail, the support  55  of  FIG. 6  is manufactured starting from a board of a commercially available type, formed by a multilayer. In particular, here the support  55  comprises a bottom insulating layer  80 ; a bottom conductive layer  81 , overlying the bottom insulating layer  80 ; an intermediate insulating layer  82 , the so called core, overlying the bottom insulating layer  80  and the bottom conductive layer  81 ; a top conductive layer  83 , overlying the intermediate insulating layer  82 ; a top insulating layer  84 , overlying the intermediate insulating layer  82  and the top conductive layer  83 ; and a top conductive layer  85 , overlying the top insulating layer  84 . These various layers of the support  55  may be referred to as a first layer, a second layer, a third layer, a fourth layer, a fifth layer, and so forth. 
     The insulating layers  80 ,  82 ,  84  may be of organic material, for example plastic, such as so-called insulating prepeg; the conductive layers  81 ,  83  and  85  may be of metal, such as copper. Possibly, the top conductive layer  83  may further comprise a layer with very low contact resistance, for example a gold-based layer, overlying the copper layer. 
     The conductive layers  81 ,  83  and  85  are shaped to form, respectively, the buried conductive region  56 , the top plate regions  88  of the capacitors  70 ,  71 , and the bottom portions  65  of the second and third contact structures  57 B,  57 C. 
     In a way not shown, the support  55  may comprise a bottom conductive layer, arranged underneath the bottom insulating layer  80  and also of metal, such as copper, possibly coated with a gold-based layer (see also the description of  FIG. 12 ). 
     In practice, here the capacitors  70 ,  71  are formed by the bottom conductive layer  81  (buried conductive region  56 ), the intermediate insulating layer  82 , and the top conductive layer  83  (top plate regions  88 ). Consequently, in this embodiment, the bottom portions  65  of the contact structures  57 A- 57 D no longer form plates of the capacitors  70 ,  71 , but are connected to the top plate regions  88  by respective vias  90  extending through the top insulating layer  84 . 
     In this embodiment, the critical distance T 1 , to be compared with the distance T 2  between the buried conductive region  56  and the first external connection region  60 , is the one between the bottom portion  65  of the second contact structures  57 B and the top plate region  88  facing it. 
       FIG. 7  shows a possible embodiment of the galvanic-coupling structures  73 . 
     In detail, here, a first and a second disk-shaped plate  92 ,  93  form the bottom portions  65  of  FIG. 5A  or the top plate regions  88  of  FIG. 6  of the first capacitor  70  and second capacitor  71 , respectively. A third and a fourth disk-shaped plate  94 ,  95  form the ends of the buried conductive region  56  of the first and second capacitors  70 ,  71 . 
     The third and fourth disk-shaped plates  94 ,  95  are here vertically aligned to the first disk-shaped plate  92  and the second disk-shaped plate  93 , respectively. In other words, as shown in  FIG. 7 , the first disk-shaped plate  92  is aligned with and overlaps the third disk-shaped plate  94 , and, as shown in  FIG. 7 , the second disk-shaped plate  93  is aligned with and overlaps the fourth disk-shaped plate  95 . 
     A conductive line  96  forms the buried conductive region  56  and directly connects or couples the third and fourth disk-shaped plates  94 ,  95  together. The conductive line  96  electrically couples the third and fourth disk-shaped plates  95 ,  96  together. The conductive line  96  may be referred to as a connection line, an electrical connection line, or some other type of line that electrically couples the third and fourth disk-shaped plates  95 ,  96  together. The conductive line  96  is integral the first and second disk-shaped plates  95 ,  96 . 
     The size and shape of the disk-shaped plates  92 - 95  and of the conductive line  96  may be decided by the designer on the basis of the isolation voltages and of the materials used to prevent electrical field accumulation areas (tip effect) and in general to minimize the maximum electrical field at the specific operating voltage. In particular, in a way known to the person skilled in the art, the geometrical characteristics are studied to provide values for the active capacitance and for the active capacitance/parasitic capacitance ratio and to minimize peeling or failure risks during thermal cycles to which the device may be subjected during manufacture or normal use. 
     For instance, the system  50  may be configured to allow one of the devices  53 ,  54  or both (but not simultaneously) to operate at a high voltage (e.g., 10 kV or higher). In this case, the disk-shaped plates  92 - 95  may have a diameter comprised between 100 μm and 1 mm, in particular 400 μm, and the conductive line  96  may have a length comprised between 500 μm and 3 mm, in particular 1 mm, and a width comprised between 5 and 100 μm, in particular 30 μm. The diameter may be equal the upper and lower limits as set forth directly above. 
     The system  50  may comprise a number of galvanic-coupling structures  73 , according to the needs. 
     For instance,  FIG. 8  shows a system  100  comprising four galvanic-coupling structures  73  forming two transmission channels  101 ,  102 , each having a respective pair of capacitances for differential transmission of the signals. In each transmission channel, the signals are, for example, transmitted by the first die  51  as potential difference between two first disk-shaped plates  92  and received by the second die  52  as potential difference between two second disk-shaped plates  93 , in case of transmission from the first die  51  to the second die  52 , and vice versa in the transmission of signals from the second die  52  to the first die  51 . 
       FIG. 9  shows a system  150  similar to the system  50  of  FIG. 5A . Consequently, the system  150  will be described only with reference to the differences, using the same reference numbers for same parts. 
     The system  150  of  FIG. 9  again comprises two dice  51 ,  52  fixed to a support  55  housing a buried conductive region  56 , but the latter overlies in part the external connection regions  60 ,  61 , so that the capacitors  70 ,  71  are arranged vertically aligned above the external connection regions  60 ,  61 . In this case, for example, the distance between the external connection regions  60 ,  61  may be 500 μm, but the thickness of the support  55  is to be chosen with a sufficient value, higher than for the system  50  of  FIG. 5A . 
     In the system  200  of  FIG. 10 , the support  55  is arranged on the dice  51 ,  52 . 
     In detail, here the dice  51 ,  52  are fixed directly to a respective external connection region  60 ,  61 , a first contact structure  257 A extends between the first die  51  and the support  55 , and a second contact structure  257 B extends between the first die  51  and the support  55 . In practice, the dice  51 ,  52  are fixed to the respective external connection regions  60 ,  61 , on a first main surface thereof and to the support  55 , on a second main surface thereof, opposite to the first main surface. 
     The contact structures  257 A,  257 B may be formed in a similar way to the contact structures  57 A- 57 D described above, and thus here comprise each a bottom portion  267 , for example formed by a die pad, metal region; an intermediate portion  266 , forming a bump region, here arranged on the bottom portion  267 ; and a top portion  265 , for example formed by a support pad region, of metal, here arranged on the intermediate portion  266 . 
     The top portions  265  of the contact structures  257 A,  257 B face respective ends, of the buried conductive region  56 ; the ends may be disk-shaped (as shown in  FIG. 7 ). Here, then, the top portions  265  of the contact structures  257 A,  257 B form plate regions, capacitively coupled to the buried conductive region  56 , to form the capacitors  70 ,  71 . 
     Alternatively, in a way similar to what shown in  FIG. 6  for the system  50 , the contact structures  257 A,  257 B may be connected by vias to respective conductive regions (not shown) formed in the support  55  and facing the ends of the buried conductive region  56 . 
     In the system  200  of  FIG. 10 , the length of the buried conductive region  56  may be comprised between 0.5 and 3 mm in the case of a distance between the external connection regions  60 ,  61  of 0.5 mm. 
     The system  200  of  FIG. 10  has the advantage that, to obtain the isolation, is sufficient to satisfy the sealing constraint for the distance T 1  between the second contact structure  57 B and the buried conductive region  56  (and/or the third contact structure  57 C and the buried conductive region  56 ), since the condition on the distance T 2  (i.e., floating with respect to the external connection regions  60 ,  61 ) is automatically satisfied. 
     According to a different embodiment, shown in  FIG. 11 , a substrate  58  of semiconductor material extends on the support  55  of the system  200  of  FIG. 10  and forms a die  59  with the support  55 . In this case, the support  55  may be formed by insulating layers of polyimide and/or oxide housing metals to form the buried conductive region  56  and the top portions  265  of the contact structures  257 A,  257 B. 
     In this way, the system  200  may be obtained using techniques of the semiconductor industry, with consequent advantages in terms of resolution, spatial dimensions control and alignment. 
       FIG. 12  shows a system  250  similar to the system  50  of  FIG. 5A . 
     In the system  250 , the external connection regions  60 ,  61  are missing, and a bottom metal layer  86  of the support  55  extends underneath the bottom insulating layer  80 . The bottom metal layer  86  is here shaped so as to form leads (of which two leads  260 ,  261  are shown, similar to the external connection regions  60 ,  61 ) for external connection of the devices  53 ,  54 . 
     The system  250  of  FIG. 12  may have a finishing of the BGA (Ball Grid Array) type with the balls of solder paste  262  (shown dashed) remolten on the leads  260 ,  261 . 
     The systems  50 ,  100 ,  150 ,  200  and  250  described herein have a high isolation level between the devices even operating at very different, high voltages. These systems moreover give rise to parasitic elements of very low value. 
     They ma be manufactured in a simple way, using machines and steps ordinary in the production of power devices. 
     Finally, it is clear that modifications and variations may be made to the system described and shown herein, without departing from the scope of the present disclosure, as defined in the attached claims. For instance, the different described embodiments may be combined so as to provide further solutions. 
     Moreover, even though the shown systems comprise only two devices, the same solution may be applied in the case of a plurality of devices, possibly with adequate spacing of the buried conductive regions  56 . 
     A packaged electronic system may be summarized as including a support ( 55 ), the support comprising an insulating organic substrate housing a buried conductive region ( 56 ), the buried conductive region being a floating region and having a first and a second portion ( 94 ;  95 ) mutually spaced; a first die ( 51 ), fixed to the support, the first die having a first main surface carrying a first die contact region ( 67 ;  267 ) capacitively coupled to the first portion of the buried conductive region; a second die ( 52 ), fixed to the support, the second die having a first main surface carrying a second die contact region ( 67 ;  267 ), capacitively coupled to the second portion of the buried conductive region; and a packaging mass ( 77 ) enclosing the first die ( 51 ), the second die ( 52 ), the first die contact region, the second die contact region, and, at least partially, the support ( 55 ). 
     The buried conductive region ( 56 ) may have an elongated shape with a first end and a second end, wherein the first portion ( 94 ) of the buried conductive region is arranged at the first end and the second portion ( 95 ) of the buried conductive region is arranged at the second end of the buried conductive region. 
     The first and second ends ( 94 ;  95 ) of the buried conductive region ( 56 ) may be disk-shaped. 
     The first and second die contact regions ( 67 ;  267 ) may face the first and, respectively, the second portions ( 94 ;  95 ), of the buried conductive region ( 56 ). 
     The support ( 55 ) may have a first and a second face ( 55 A,  55 B), the first and second dice ( 51 ,  52 ) being fixed to the first face ( 55 A) of the support. 
     The system may include a first and a second external connection region ( 60 ,  61 ) of metallic material, the first and second external connection regions extending on the second face ( 55 B) of the support ( 55 ) at a first mutual distance (D 2 ), the external connection regions being electrically connected by connection lines ( 76 ) to the first and second dice ( 51 ,  52 ). 
     The first and second dice ( 51 ,  52 ) may be arranged at a second mutual distance (D 1 ), wherein the first distance (D 2 ) is greater than the second distance. 
     The first and second dice ( 51 ,  52 ) may be arranged at a second mutual distance (D 1 ), wherein the first distance (D 2 ) is smaller than the second distance. 
     The system may further include a first and a second contact structure ( 57 B,  57 C), wherein: the first contact structure ( 57 B,  57 C) comprises a first plate region ( 65 ), capacitively coupled to the first portion ( 94 ) of the buried conductive region ( 56 ) and arranged on the first face ( 55 A) of the support ( 55 ); and a first bump region ( 66 ), contiguous to the first plate region and to the first die contact region, and the second contact structure comprises a second plate region ( 65 ), capacitively coupled to the second portion ( 95 ) of the buried conductive region ( 56 ) and arranged on the first face ( 55 A) of the support ( 55 ); and a second bump region ( 66 ), contiguous to the second plate region and to the second die contact region. 
     The distance (T 1 ) between the buried conductive region ( 56 ) and the first face ( 55 A) of the support ( 55 ) may be equal to or smaller than the distance (T 2 ) between the buried conductive region ( 56 ) and the first external connection region ( 57 B). 
     The first and second dice may have a respective second main surface, the first and second dice ( 51 ,  52 ) being fixed to the support ( 55 ) on the respective first main surface and to a respective external connection region ( 60 ,  61 ), of metal, on the respective second main surface. 
     The support ( 55 ) may be a multilayer formed by a plurality of conductive layers including at least a first, a second and a third conductive layer ( 81 ,  83 ,  85 ) spaced apart by respective insulating layers ( 82 ,  84 ), the buried conductive region ( 56 ) may be formed in the first conductive layer ( 81 ) of the plurality of conductive layers, a first and a second capacitive plate region ( 88 ) may be formed in the second conductive layer ( 83 ) and directly face the first and, respectively, the second portions ( 94 ,  95 ) of the buried conductive region ( 56 ), and a first and a second support contact region ( 65 ;  265 ) may be formed in the third conductive layer ( 85 ) and may be electrically connected to the first and, respectively, the second capacitive plate regions ( 88 ), through vias ( 90 ) extending across a respective insulating layer ( 84 ). 
     The first and second support contact regions ( 65 ;  265 ) may be part of a first and, respectively, a second contact structure ( 57 B,  57 C;  257 A,  257 B), the first contact structure ( 57 B;  257 A) may further include a first bump region ( 66 ;  266 ) contiguous to the first support contact region ( 65 ;  265 ) and to the first die contact region ( 67 ;  267 ), and the second contact structure ( 57 C;  257 B) may further include a second bump region ( 66 ;  266 ) contiguous to the second support contact region ( 65 ;  265 ) and to the second die contact region ( 67 ;  267 ). 
     The distance (T 2 ) between the buried conductive region ( 56 ) and the first external connection region ( 57 B) may be approximately equal to the distance (T 1 ) between the buried conductive region ( 56 ) and the first capacitive plate region ( 88 ). 
     The various embodiments described above can be combined to provide further embodiments. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications to provide yet further embodiments. 
     These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.