FR3022697A1 - ELECTRICAL CONNECTION DEVICE WITH CONNECTING ELEMENTS COMPRISING DEFORMABLE MEMBRANES - Google Patents

Abstract

An electrical connection device (100) for hybridization to an electronic device, having one or more first electrical connection members (112) disposed on a front face (102) of the electrical connection device such that each first electrical connection member comprises at least a first electrically conductive membrane delimiting, with the front face of the electrical connection device, at least one first cavity, the first membrane being secured to the front face of the electrical connection device at least level of the periphery of the first cavity, - at least one electrically conductive element (116) disposed on the first membrane of said first electrical connection element and intended to be in contact with at least one contact pad of the electronic device.

Description

TECHNICAL FIELD AND PRIOR ART The invention relates to the field of permanent or temporary hybridization between electronic devices or circuits. The invention is advantageously applied for producing an electronic test circuit intended to be temporarily hybridized to an electronic device to be tested, or for producing an electronic circuit comprising two electronic devices hybridized to each other. permanently. In the field of so-called "3D" electronic circuits, that is to say electronic circuits comprising devices stacked on top of one another, low-pitch vertical electrical connections, or period, (less than or equal to about 100 μm). ) are often used to electrically connect the superimposed devices together. These connections are generally made on one side of one of the devices in the form of points, or inserts, these points being intended to be inserted into contact pads formed on one side of another of the devices. Several constraints are taken into account for the realization of these connections. First, the connections made must have good electrical conductivity. The materials of the tips must also have a certain hardness to allow their penetration into the contact pads. Finally, the circuit comprising the tips must have a certain mechanical flexibility to account for differences in thickness, geometry and materials with the contact pads.

Such connections are for example used to achieve a low-step test structure for 3D or photonic circuits. In this context, a component called "space transform", or interposer, is generally used to make the link, or the adaptation, between the pitch of the connection pads of the device under test (generally comprising a silicon wafer, the contact pads being made with a step of the order of 100 μm or less) and that of the connection elements of the test interface (generally made on an integrated circuit and which comprises connection elements made with a pitch greater than that studs of the device to be tested). This component can be made of silicon and incorporates test tips made with a small pitch corresponding to that of the contact pads of the device under test. A force is applied between the device under test and the component in order to have a mechanical penetration of the points in the contact pads of the device under test. A difficulty related to the achievement of these tips concerns their mechanical properties, each of the tips having to have a certain flexibility of vertical displacement (overdrive) despite their small pitch and the defects of uniformity of height of the test tips or studs. contact of the device tested. The penetration of the tips into the contact pads must be deep enough to achieve good ohmic contact, but not too deep to avoid damaging the contact pads and allow the tips to be detached from the contact pads after the test.

Another example of the need for such connections is the production of permanent and selective "3D" electrical connections. During the 3D assembly of microelectronic components, electrical connections are made between the opposite studs of the two components. One possibility is to place tips on one of the two components and contact pads on the other of the two components, and to insert the tips into the opposing studs during assembly of the two components by exerting pressure between them. . These tips form "micro-inserts" here. If the tips are present on the entire face of the component, by exerting said pressure, the tips facing insulating areas and not contact pads crash into the insulation of the other component without penetrating completely, and may damage it.

It is therefore useful to have tips having a certain tolerance and mechanical flexibility to avoid damaging the face of the component comprising the contact pads. Document US 2012/0249173 A1 describes an exemplary embodiment of a component comprising test points made with a small pitch. The tips are made by structuring a material (deposition and etching, or electrodeposition) on a silicon interposer. The disadvantage of this solution is that it offers no answer to the problems of mechanical flexibility and overdrive tolerance that are desired. Documents US 2002/0053734 A1 and US 2006/0006889 A1 describe the production of test tips in the form of mechanical structures that address the problem of mechanical flexibility and overdrive tolerance. However, these structures require either an insertion into the component or a mechanical attachment which prevents their realization with a small pitch, that is to say less than about 100 μm. US 7,868,636 B2, US 2010/0164526 A1 and US 2010/0308855 A1 disclose making test tips in the form of flexible rods. Although answering the problem of the mechanical flexibility and the overdrive tolerance, these rods have dimensions, in the plane of the substrate, which are important and which prevent their realization in the form of a matrix with a weak pitch .

SUMMARY OF THE INVENTION An object of the present invention is to propose a new electrical connection device intended to be hybridized to an electronic device, whose electrical connection elements have good mechanical flexibility and good tolerance in terms of vertical displacement. (Overdrive) while being compatible with one embodiment of the electrical connection elements with a small pitch, for example less than about 100 μm. For this, the present invention proposes an electrical connection device intended to be hybridized to an electronic device, comprising one or more first electrical connection elements disposed on a front face of the electrical connection device such that each first electrical connection element comprises: at least one first electrically conductive membrane delimiting, with the front face of the electrical connection device, at least one first cavity, the first membrane being secured to the front face of the electrical connection device at least at the periphery of the first cavity, 3022697 4 - at least one electrically conductive element disposed on the first membrane of said first electrical connection element and intended to be in contact with at least one contact pad of the electronic device. Thus, each first electrical connection element comprises a first electrically conductive membrane defining a cavity, advantageously closed, on which is disposed at least one electrically conductive element, the first membrane being anchored to a support corresponding to the front face of the connection device. electric. The cavity present under each electrically conductive element imparts good mechanical flexibility to the first 10 electrical connection elements. Thus, when the electrically conductive elements of the electrical connection device are arranged against the contact pads of the electronic device intended to be hybridized with the electrical connection device, a good electrical contact is obtained between the first electrical connection elements and the contact pads. thanks to the flexibility conferred by the cavities at each of the first 15 electrical connection elements, even in the presence of differences in thickness and / or height and / or geometry and / or materials at the contact pads and / or first electrically conductive elements. This flexibility also makes it possible, in the case where certain first electrical connection elements are not arranged opposite contact pads, not to damage the electronic device which is hybridized with the electrical connection device. The mechanical flexibility obtained also makes it possible to achieve penetration of the electrically conductive elements in the contact pads which is deep enough to achieve a good ohmic contact, but not too deep to avoid damaging the contact pads and to allow the first elements electrically 25 conductors to be detached from the contact pads in the case of an electrical connection device for forming a test circuit. Finally, compared with the test tips made with flexible rods, the structures formed by the first membranes do not require the creation of anchoring pillars necessary for the production of the flexible rods of the prior art, which makes it possible to to make the first electrical connection elements with a small pitch, for example less than about 100 μm. The connection between the membrane and the front face of the electrical connection device is advantageously continuous, but may, for reasons of implementation method, have one or more openings at this periphery which make this connection discontinuous or partially continuous. . For each first electrical connection element, the first membrane may be secured to the front face of the electrical connection device at the entire periphery of the first cavity.

The electrical connection device may comprise passive devices (capacitors, inductances, resistors) making it possible to improve the quality of the signals collected by the first electrical connection elements, and / or active elements (for example transistors) forming, for example protection devices such as ESD devices ("Electro-Static Discharge"), and / or multiplexing and / or signal processing analogically or numerically collected by the first electrical connection elements. The first electrical connection elements may be arranged in a matrix with a pitch less than about 100 μm. Each electrically conductive element may comprise at least one portion of electrically conductive material, one end of which forms one or more points, each point being of substantially convex or flat or pointed shape. Each electrically conductive element can advantageously form three points. A shape is said to be curved when it represents a portion of a sphere, such as a hemisphere, or is of rounded shape. Unlike a curved shape, a shape is said to be flat when it is defined in a plane. Each first membrane may form a cover of the first cavity which is delimited by said first membrane, the cover being of substantially flat or curved shape. The hood anchor at the base of the cavity may have a substantially circular shape (such as a circle or an ellipse) or a substantially polygonal or rectangular shape (such as a rectangle or a square or a rhombus, etc. .). Each tip or multi-tip or top of the portion of electrically conductive material may advantageously be placed on a central axis of the first membrane. Each first membrane may be connected to at least one electrically conductive pad formed in the electrical connection device and itself connected to at least one second electrical connection element disposed on a rear face of the electrical connection device.

The pitch of the first electrical connection elements may be different from the pitch of the second electrical connection elements. In this case, the electrical connection device can enable the steps of the contact pads of the device to be hybridized to be matched to the electrical connection device with that of contact pads of another device intended to be hybridized at the face 15. rear of the electrical connection device. In this case, each second electrical connection element may comprise at least one portion of electrically conductive material whose apex is substantially domed or flat or pointed. The electrical connection device may furthermore comprise at least: a substrate, one or more superposed dielectric layers and disposed on the substrate and forming the front face of the electrical connection device, at least one electrical interconnection layer; disposed beneath the dielectric layer or between the dielectric layers, each electrically conductive pad being connected to the electrical interconnection layer; one or more electrically conductive vias traversing at least the substrate and electrically connecting each second electrical connection element to the dielectric layer; electrical interconnection. The dielectric layer (s) may comprise at least one mineral or polymer dielectric material.

The electrical connection device may further comprise at least one second cavity formed through the substrate and such that at least a part of the dielectric layer or layers on which at least one first electrical connection element is formed forms at least a second membrane at the second cavity. This or these second cavities give the electrical connection device a degree of additional mechanical flexibility. Alternatively, the electrical connection device may further comprise a plurality of second cavities formed through the substrate and such that portions of the dielectric layer (s) on each of which is disposed a first electrical connection member form second membranes at the second cavities. The invention also relates to an electronic test circuit comprising at least one electrical connection device as described above, in which the electronic device is intended to be tested by the electronic test circuit, and in which the rear face of the The connection device is hybridized to an electronic test interface via the second electrical connection elements. In this case, the electrical connection device can form an interposer to adapt the pitch of the contact pads of the device tested with that of the pads of the electronic test interface.

The invention also relates to an electronic circuit comprising at least one electrical connection device as described above and hybridized to the electronic device such that the electrically conductive elements of the electrical connection device are anchored in the contact pads of the electronic device. Such an electronic circuit can correspond to a 3D circuit.

The invention also relates to a method for producing an electrical connection device intended to be hybridized to an electronic device, comprising the production of one or more first electrical connection elements on a front face of the electrical connection device at least by implementing, for each first electrical connection element, steps of: - producing at least a portion of sacrificial material on the front face of the electrical connection device; - Making at least a first electrically conductive membrane such that it covers at least the sacrificial material portion and is secured to the front face of the electrical connection device at least at the periphery of the portion of sacrificial material; - Making at least one release hole through the first membrane; removing the portion of sacrificial material through the release hole, forming at least a first cavity delimited by the first membrane and the front face of the electrical connection device; - Making at least one electrically conductive element on the first membrane such that it is intended to be in contact with at least one contact pad of the electronic device.

The method may further comprise, prior to the production of the first electrical connection element or elements, the implementation of the following steps: - production, through at least a portion of the thickness of a substrate, of a or more electrically conductive vias; - Making at least one electrical interconnection layer between the substrate and a dielectric layer or between several dielectric layers, - Making one or more electrically conductive pads in the electrical connection device and to which the first membrane or membranes are intended to be connected; And further comprising, after completion of the first one or more electrical connection elements, the implementation of the following steps: - making one or more second electrical connection elements on a rear face of the electrical connection device such as each The first membrane is connected to at least one of the second electrical connection elements via one or one of the electrically conductive pads, the electrical interconnection layer, and one or more electrically conductive vias. The method may furthermore comprise, between the production of the first electrical connection element or elements and the production of the second or fifth electrical connection elements, the production of at least a second cavity through the substrate and such that at least a part of the dielectric layer or layers on which at least one first electrical connection element is arranged forms at least one second membrane at the level of the second cavity. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood on reading the description of exemplary embodiments given purely by way of indication and in no way limiting, with reference to the appended drawings in which: FIG. 1 schematically represents a sectional view of profile of an electrical connection device, object of the present invention, according to a first embodiment; - Figure 2 schematically shows a top view of a first electrical connection element of the electrically connecting device according to the first embodiment; - Figure 3 schematically shows a sectional sectional view 20 of an electrical connection device, object of the present invention, according to a second embodiment; - Figure 4 shows schematically a sectional sectional view of a portion of an electrical connection device, object of the present invention, according to a third embodiment; Figure 5 schematically shows a sectional sectional view of a portion of an electrical connection device, object of the present invention, according to a fourth embodiment; FIG. 6 schematically represents a profile sectional view of an electrical connection device, object of the present invention, according to a fifth embodiment; - Figure 7 schematically shows a sectional sectional view 5 of a portion of an electrical connection device, object of the present invention, according to a sixth embodiment; - Figure 8 schematically shows a profile sectional view of an electronic test circuit, also object of the present invention, according to a particular embodiment; Figure 9 schematically shows a profile sectional view of an electronic circuit, also object of the present invention, according to a particular embodiment; FIGS. 10A to 10K schematically represent steps of a method for producing an electrical connection device, object of the present invention, according to a particular embodiment. Identical, similar or equivalent parts of the different figures described below bear the same numerical references so as to facilitate the passage from one figure to another. The different parts shown in the figures are not necessarily in a uniform scale, to make the figures more readable. The different possibilities (variants and embodiments) must be understood as not being exclusive of each other and can be combined with one another. DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS Referring first to FIG. 1, which schematically shows an electrical connection device 100 according to a first embodiment. In this first embodiment, the device 100 corresponds to an interposer comprising a front face 102 intended to be coupled to a device to be tested, and a rear face 104 intended to be coupled to a test interface. The device 100 is intended to electrically connect the device to be tested with the test interface, and advantageously makes it possible to adapt the pitch of contact pads of the device to be tested to that of contact pads of the test interface. The device 100 comprises a substrate 106 comprising, for example, a semiconductor such as silicon. One or more electrical interconnection layers 108 (BEOL, or "Back-end Of Line") are disposed on the substrate 106, on the side of the front face 102, and form, in several dielectric layers 110 comprising at least one mineral material such as SiO 2, SiON, SiN, etc., and deposited on the substrate 106, one or more levels of electrical interconnections interconnected by vias 111. Electrical access to the electrical interconnection layers 108 from the front face 102 is formed by electrically conductive pads 113 formed in the dielectric layers 110 and at the front face 102. First electrical connection elements 112 are arranged on the front face 102 and are electrically connected to the layers 108 by the Intermediate pads 113. Each element 112 comprises a first membrane 114 formed of at least one electrically conductive material such as doped silicon or silicide (for example SiNi or SiPt), and / or metal (eg copper, aluminum, tungsten or nickel) and / or graphite. The first membrane 114 may also be formed of at least one dielectric material such as SiO 2, the electrical conductivity of this membrane being in this case provided by an additional electrically conductive layer of the membrane. An electrically conductive element 116, corresponding to a test tip in this first embodiment, is disposed on each of the membranes 114. The elements 116 advantageously comprise metal such as copper, tungsten, aluminum, nickel or still rhodium, or a semiconductor coated with metal. These elements 116 are intended to be applied against the contact pads of the device under test with a force allowing mechanical penetration of the elements 116 in the contact pads of the device under test. The material or materials of the elements 116 are chosen in particular as a function of the desired hardness to form the contact with the contact pads of the device under test, and therefore in particular as a function of the fragility of these contact pads.

In FIG. 1, three first electrical connection elements 112 are shown. However, the device 100 generally comprises several hundreds, or several thousands or tens of thousands of elements 112. In order to obtain a certain mechanical flexibility in terms of vertical displacement of the elements 116 despite their small pitch and possible defects uniformity of height of the elements 116 and / or contact pads of the device under test, while having a penetration of the elements 116 in the contact pads of the device under test which is deep enough to achieve a good ohmic contact between the elements 116 and the contact pads, but not too deep to avoid damaging the contact pads and allowing the elements 116 to be detached from the contact pads after the test, each element 116 is disposed on a portion of the membrane 114 forming, between the front face 102 and a lower face of the membrane 114 located on the side of the front face 102, a cavity 118. On the example of the fi 1, each of the cavities 118 has a bottom wall formed by the front face 102, i.e., an upper face of the dielectric layers 110. The side walls and the top wall of each cavity 118 are formed by the membrane 114 which rests on the dielectric layers 110. The portions of the membranes 114 forming the walls of the cavities 118 have, with respect to the front face 102, a convex convex shape. The cavities 118 are here closed, and the portions of the membranes 114 defining the cavities 118 are anchored to the front face 102 over the entire periphery of the cavities 118. Thus, when the elements 116 are applied against the contact pads of the device under test, the membranes 114 which are subjected to a too great force, in the direction perpendicular to the front face 102, can deform in this direction and thus absorb a part of this force. These membranes 114 form support elements 116 having good mechanical flexibility (good overdrive). FIG. 2 represents a schematic view from above of one of the first connection elements 112. The elements 112 are arranged next to each other, for example in the form of a matrix, with a pitch for example between about 20.degree. um and 3022697 13 100 um, or even less than 20 um. The dimensions of the sides of the device 100 are, for example, between 1 mm and 10 mm. The device 100 comprises, at its rear face 104, second electrical connection elements 120 electrically connected to the layers 108 via conductive vias. 122 passing through the substrate 106 from its front face to its rear face. The conductive vias 122 also pass through another dielectric layer 123 disposed on the rear face of the substrate 106 and forming the rear face 104 of the device 100. The elements 120 each comprise a portion of electrically conductive material 121 disposed on a portion of a layer of Nucleation 125 and, at their apex, another portion of electrically conductive material 124, for example curved or flat, comprising for example a creep metal such as SnAg, NiAu or any other suitable alloy, and intended to be in contact with the contact pads of the test interface. Portion 124 may also include a harder metal such as tungsten. The thickness of the assembly formed of the substrate 106 and the layers 110, 123 is for example between about 200 μm and 400 μm. The compensation for the height distortion that can be achieved by the device 100, that is to say the maximum height position difference between two elements 112 of the device 100 may be a few tens of microns, for example between about 10 um and 200 μm. Between two adjacent elements 112, this difference may be of the order of one micron or less, for example between about 0.5 μm and 1 μm. In a variant of the example described with reference to FIGS. 1 and 2, the device 100 may comprise, on and / or in the substrate 106, passive devices (capacitors, inductances, resistors) making it possible to improve the quality of the signals 25 measured by the elements 116, and / or active devices comprising, for example, transistors and capable of forming devices for protecting the device to be tested, for example ESD devices ("Electro-Static Discharge"), and / or multiplexing devices. and / or digital or analog processing of the measured signals. In the previously described embodiment, the membranes 114 are doped silicon or silicide, or more generally a electrically conductive material allowing the membranes 114 to have a certain flexibility or flexibility. Alternatively, the membranes 114 may be formed by the superposition of several layers of material, for example a semiconductor coated with a metal layer.

Figure 3 schematically shows the device 100 according to a second embodiment. With respect to the first embodiment, each element 112 comprises, in place of the element 116 in the form of a tip, an element 116 forming a multi-point, here three points (only two points are visible in FIG. The third tip is outside the section plane). Such an element 116 is well adapted to make contact with contact pads of the tested device of curved and hard shape, corresponding for example to metal balls, because in this case, such contact pads can easily be inserted between the The elements 116 are thus well centered with respect to the contact pads of the device under test and avoid degrading such rounded and hard contact pads. The distance "a" between the peaks of two points of a multi-point element is, for example, less than about 15 μm. Figure 4 schematically shows a part of the device 100 according to a third embodiment. In this figure, although the device 100 has several elements 112, only one of these elements 112 is shown. With respect to the first embodiment, each element 112 comprises, in place of the element 116 in the form of a point, an element 116 comprising a portion 128 of electrically conductive material surmounted by a conductive portion 130 (which is curved on the FIG. 4, but which could be planar), for example similar to the portions 121 and 124 of the second members 120 on the rear face 104 of the device 100. The portion 130 forms a tip whose crown is curved. The conductive portion 130 comprises, for example, a creep metal such as SnAg or NiAu, the hardness of which is lower than the metal forming the elements 116 in the form of tips or multi-tips as in the first and second embodiments, or a harder metal such as tungsten. Such elements 112 are well suited to make electrical contact with contact pads of the device under test which are not suitable for contact with points, such as for example copper pads surrounded by insulation, forming a flat surface. for example intended to be carried on a chip by direct bonding. Such elements 116 make it possible to maintain the integrity of the contact pads of the device under test. In this third embodiment, the aspect ratio, or aspect ratio, of the tip 116 may be greater than 1 or even greater than 10 or 30. Such a high form factor is advantageous when a great deal of mechanical flexibility is required. or when the spacing between the test tip and the contact pad to be tested is variable or high. The form factor, called AR, of the tip 116 is defined by the following formula: AR = H / (4nA) 1n with H corresponding to the height of the tip 116 (dimension along the Z axis), and A corresponding to the surface of its projection in the plane of the substrate 15 (parallel to the plane (X, Y)). Figure 5 shows schematically a part of the device 100 according to a fourth embodiment. In this figure, although the device 100 has several elements 112, only one of these elements 112 is shown. With respect to the first embodiment in which the membranes 114 form cavities 118 of curved shape, the membranes 114 according to this fourth embodiment delimit flat cavities 118, the sectional view (as shown in Figure 5) is of rectangular or square shape, that is to say cavities 118 of substantially parallelepipedal shape, and advantageously parallelepiped rectangle. The shape of the anchoring zone at the base of the cavity is advantageously substantially rectangular (such as a rectangle or a square or a rhombus) but may also have a different shape, for example polygonal or other. Such an advantageous configuration makes it possible to give the membranes 114 more flexibility when they are subjected to a pressing force from the elements 116 in contact with the contact pads of the device under test.

As a variant of this fourth embodiment, the cavities 118 may have a shape other than rectangular. Further, the tip-shaped member 116 of each member 112 of the device 100 according to the fourth embodiment may be replaced by a multi-tip member 116 as previously described for the second embodiment, or by a element 116 having portions 128 and 130 as previously described for the third embodiment. Figure 6 shows schematically the connection device 100 according to a fifth embodiment. With respect to the first embodiment, one or more second cavities 132 are formed at the rear face 104 of the device 100, through the substrate 106 and the dielectric layer 123. The portions of the dielectric layers 110 and the layers of electrical interconnections 108 arranged at this or these cavities 132 form second membranes providing a greater flexibility to the device 100. Such a cavity 132 may be made such that several elements 112 15 are present on the second membrane formed by this cavity 132, for example, facing the center of the matrix formed by elements 112. In this fifth embodiment, the dielectric layer or layers 110 advantageously comprise an elastic material such as a polymer, so that the flexibility provided by the presence of the one or more cavities 132 is coupled to a second, less rigid membrane than in the case of dielectric layers s 110 having SiO 2 or SiN. The dielectric layers 110 may also be formed by one or more layers of inorganic material, and one or more layers of polymeric material. In a variant, a plurality of cavities 132 may be made in the device 100 such that only one connection element is present on the second membrane formed by this cavity 132, as in the example of FIG. several cavities 132 can also be applied to connection devices 100 previously described in connection with FIGS. 1 to 5. FIG. 8 represents an electronic test circuit 1000 comprising an electrical connection device 100 according to one of the embodiments 3022697 17 previously described. The circuit 1000 is arranged opposite an electronic device 1002 intended to be tested by the electronic test circuit 1000. The device 1002 comprises contact pads 1004 in which the elements 116 in the form of tips are intended to be inserted. The circuit 1000 is intended to be temporarily hybridized to the device 1002 during the test of the device 1002. The rear face 104 of the device 100 is hybridized to an electronic test interface 1006 via the second electrical connection elements 120. Thus, various electrical tests of the device 1002 can be performed by the electronic test interface 1006 via the electrical connections made between the device 1002 and the interface 1006 via the contact pads 1004 and the device 100. FIG. 9 represents an electronic circuit 1100 formed by a "3D" assembly between the electrical connection device 100 and an electronic device 1102. The device 100 is permanently hybridized to the device 1102 thanks to the elements 112 inserted into contact pads 1104 of the device 1102 , Thus forming the electrical connections between the device 100 and the device 110 2. Alternatively, the device 100 could be coupled, at its back side, to another electronic device and / or the device 1102 could be coupled to another electronic device. With reference to FIGS. 10A to 10K, a method 20 for producing the electrical connection device 100 according to the first embodiment, corresponding to that shown in FIG. 1, is described. In these figures, the production of a single first electrical connection element 112 is shown. The method is implemented from the substrate 106 having on its front face a first of the dielectric layers 110, for example of SiO 2 or SiN 25 (FIG. 10A). The conductive vias 122 are then made through at least a portion of the thickness of the substrate 106, at its front face (Figure 10B). For this, a deep etching is carried out through the front face of the substrate 106, forming holes through the portion of the thickness of the substrate 106 and at which the vias 122 will be formed. insulation, for example an SiO 2 layer, is then deposited on the walls of the holes, and then an adhesion and nucleation layer is deposited on the insulating dielectric layer, for example via an electrolytic deposition (layers not shown in FIG. Figure 10B). The conductive material vias 122, for example copper, is then deposited by filling the holes. The substrate 106 may for example have a thickness of 500 μm or 750 μm, and the vias 122 may be made to a height of about 100 μm. The interconnection layers 108, the vias 111, the dielectric layers 110 and the pads 113 are then made on the dielectric layer disposed on the front face of the substrate 106, for example via damascene-type deposits. These steps 10 further form the front face 102 of the device 100 (FIG. 10C). A sacrificial layer, comprising for example polymer or resin, is then deposited on the front face 102. This sacrificial layer is then structured by etching so that the remaining portions 134 of this layer correspond to the volumes of the cavities 118 intended to be made ( Figure 10D). In the case of a sacrificial polymer layer, a plasma-type etching 02 may be used to form convex-shaped polymer portions for producing cavities 118 as shown in FIG. Portions of sacrificial material may also be obtained by carrying out reflux.

The membranes 114 are then made by depositing an electrically conductive layer, for example metal such as Cu, AI, W, Rh, Rt, etc., and / or doped silicon or silicide , covering the remaining portions of the sacrificial layer. This or these electrically conductive layers are then etched so that the remaining portions of this or the layers form the first membranes 114, and form the covers of the future cavities 118 (FIG. 10E). Release holes are then made through these covers, and then the sacrificial material covered by the membranes 114 is then etched through these release holes, for example via dry and / or humic etching, forming the cavities 118 (FIG. 10F). .

The material or materials, for example a metal, intended to form the elements 116 are then deposited on the membranes 114 and structured by wet etching to form the elements 116 (FIG. 10G). It is possible that the elements 116 block the clearance holes previously made through the membranes 114.

These holes can be plugged or not, with the material or materials of the elements 116 or other materials (eg polymer). The structure obtained is then glued temporarily, at its front face 102, to a support forming a mechanical handle (not visible in Figures 10H to 10K). The rear face of the structure, that is to say the rear face of the substrate 106, is then thinned to obtain the desired thickness and in particular to reach the vias 122. A passivation of the rear face can then be performed via the deposition of a passivation layer 123, then openings are made through the layer 123 to make resumption of contact vias 122 (Figure 10H). An ECD electrochemical deposition, for example by electrolysis, of the nucleation layer 125 is then carried out at the rear face 104. An electrolytic growth then forms the portions 121. The portions 124 are then produced by depositing on the portions 121 ( Figure 101). The nucleation layer is then etched so as to keep only certain portions forming part of the connection elements 120 (FIG. 10J). A possible reflux may be implemented when the material of the portions 124 is a creep material such as SnAg, as shown in Figure 10K. Finally, the device 100 obtained is separated from the temporary handle secured to the front face 102 of the device 100. For the embodiment of the device 100 comprising one or more cavities 132 as previously described in connection with FIGS. 6 and 7, steps similar to those previously described for the realization of the device 100 according to the first embodiment are implemented. The cavity or cavities 132, however, are made by etching through the rear face of the structure, just after the step of securing the structure with the temporary mechanical handle.

In all the embodiments and examples previously described, the first membranes 114 are arranged directly on the first face 102 and the first cavities 118 are delimited by the first membranes 114 and the front face 102. In a variant, the first membranes 114 can be made not directly on the first face 102 but on supports which are arranged on the front face 102. Thus, the cavities 118 are in this case formed between the first membranes 114 and these supports. Such supports may correspond to simple mechanical supports, or may comprise other elements such as, for example, a piezoelectric material placed between two electrodes, which makes it possible to electrically control the position of the support by applying a suitable electrical voltage across the electrodes. .

Claims (16)

REVENDICATIONS1. An electrical connection device (100) for hybridization to an electronic device (1002, 1102), having one or more first electrical connection elements (112) disposed on a front face (102) of the electrical connection device (100) such as each first electrical connection element (112) comprises: - at least a first electrically conductive membrane (114) delimiting, with the front face (102) of the electrical connection device (100), at least a first cavity (118), the first membrane (114) being secured to the front face (102) of the electrical connection device (100) at least at the periphery of the first cavity (118), - at least one electrically conductive element (116) disposed on the first membrane (114) of said first electrical connection element (112) and intended to be in contact with at least one contact pad (1004, 1104) of the electronic device (1002, 1102). 2. Electrical connection device (100) according to claim 1, wherein, for each first electrical connection element (112), the first membrane (114) is secured to the front face (102) of the electrical connection device. (100) at the entire periphery of the first cavity (118). The electrical connection device (100) according to one of the preceding claims, wherein the first electrical connection elements (112) are arranged in a matrix with a pitch less than about 100 μm. 4. Electrical connection device (100) according to one of the preceding claims, wherein each electrically conductive element (116) comprises at least one portion of electrically conductive material one end of which forms one or more tips, each tip being substantially curved or flat or pointed shape. 5. Electrical connection device (100) according to one of the preceding claims, wherein each first membrane (114) forms a cover of the first cavity (118) which is delimited by said first membrane (114), the hood being of substantially flat or curved shape. 6. Electrical connection device (100) according to one of the preceding claims, wherein each first membrane (114) is connected to at least one electrically conductive pad (113) formed in the electrical connection device (100) and it - Even connected to at least one second electrical connection element (120) disposed on a rear face (104) of the electrical connection device (100). 15 7. Electrical connection device (100) according to claim 6, wherein each second electrical connection element (120) comprises at least one portion of electrically conductive material (121, 124) whose apex is substantially convex or flat or pointed. 8. Electrical connection device (100) according to one of claims 6 or 7, further comprising at least: - a substrate (106), - one or more dielectric layers (110) superimposed and arranged on the substrate (106) and forming the front face (102) of the electrical connection device (100), - at least one electrical interconnection layer (108) disposed under the dielectric layer (110) or between the dielectric layers (110), each electrically conductive pad (113) being connected to the electrical interconnection layer (108), one or more electrically conductive vias (122) passing through at least the substrate (106) and electrically connecting each second electrical connection element (120) to the electrical interconnect layer (108). 5 An electrical connection device (100) according to claim 8, wherein the one or more dielectric layers (110) comprise at least one mineral or polymeric dielectric material. The electrical connection device (100) according to one of claims 8 or 9, further comprising at least a second cavity (132) formed through the substrate (106) and such that at least a portion of the dielectric layers (110) on which at least one first electrical connection element (112) is arranged forms at least one second membrane at the second cavity (132). 15 The electrical connection device (100) according to one of claims 8 or 9, further comprising a plurality of second cavities (132) formed through the substrate (106) and such as portions of the dielectric layer (s) (110). each of which is provided with a first electrical connection element (112) form second membranes at the second cavities (132). 20 12. An electronic test circuit (1000) comprising at least one electrical connection device (100) according to one of claims 6 to 11, wherein the electronic device (1002) is intended to be tested by the electronic test circuit 25. (1000), and wherein the rear face (104) of the connecting device (100) is hybridized to an electronic test interface (1006) via the second electrical connection elements (120). 3022697 24 13. An electronic circuit (1100) comprising at least one electrical connection device (100) according to one of claims 1 to 11 hybridized to the electronic device (1102) such that the electrically conductive elements (116) of the electrical connection device (100). ) are anchored in the contact pads (1104) of the electronic device (1102). 14. A method of producing an electrical connection device (100) intended to be hybridized to an electronic device (1002, 1102), comprising the production of one or more first electrical connection elements (112) on a front face. (102) of the electrical connection device (100) at least by the implementation, for each first electrical connection element (112), of steps of: - producing at least a portion of sacrificial material (134) on the front face (102) of the electrical connection device (100); - Making at least a first electrically conductive membrane (114) such that it covers at least the portion of sacrificial material (134) and is secured to the front face (102) of the electrical connection device (100) at least at the periphery of the portion of sacrificial material (134); - providing at least one release hole through the first membrane (114); Removing the portion of sacrificial material (134) through the release hole, forming at least a first cavity (118) delimited by the first membrane (114) and the front face (102) of the electrical connection device (100). ); - Making at least one electrically conductive element (116) on the first membrane (114) such that it is intended to be in contact with at least one contact pad (1004, 1104) of the electronic device (1002, 1102). ). 15. The method of claim 14, further comprising, prior to the production of the first electrical connection elements (112), the implementation of the following steps: - realization, through at least a part of the a thickness of a substrate (106), one or more electrically conductive vias (122); - Making at least one electrical interconnection layer (108) between the substrate (106) and a dielectric layer (110) or between several dielectric layers (110), - Making one or more electrically conductive pads (113). ) in the electrical connection device (100) and to which the first membrane or membranes (114) are intended to be connected; and further comprising, after the making of the first 10 electrical connection elements (112), carrying out the following steps: - producing one or more second electrical connection elements (120) on a rear face (104); ) of the electrical connection device (100) such that each first membrane (114) is connected to at least one of the second electrical connection elements (120) via the or one of the electrically conductive pads (113), the electrical interconnect layer (108) and the one or more electrically conductive vias (122). 16. The method of claim 15, further comprising, between the production of the first electrical connection elements (112) and the production of the second or second electrical connection elements (120), the production of at least a second cavity (132) through the substrate (106) and such that at least a portion of the at least one dielectric layer (110) on which at least one first electrical connection element (112) is disposed forms at least one second level of the second cavity (132). 25