EA010269B1 - Contact assembly on opposed contacts with capillary connecting element and method for manufacturing thereof - Google Patents

Abstract

The invention relates to electronic technology, more particular to permanent solded links widely used in manufacturing of articles for use in micro-electronics and semi-conducting devices. A contact assembly is proposed on opposed contacts consisting of two flat contacts connected therebetween by a linking element designed as a crosspiece made from an electroconductive material, wherein each of said contacts is arranged on the surface of one of two coplanar carriers, the - contacts oriented to each other, and clearance between coplanar carriers of the opposed contacts and around the linking element is filled by dielectric material, according to the invention the linking element is made as a capillary with end flanges and filled with electroconducting binding material drawn in said capillary from opposed contacts under the action capillary forces arising at transition binding electroconductive material into liquid state forming mechanically-stable electroconductive connection between the opposed contacts, wherein said capillary is made as an orifice coated by wet electroconductive binding material in plane-parallel plate from dielectric material. There proposed a method of manufacturing contact assembly, in which the height of solder rise in the capillary linking element is determined by the formula:where ρ=8540 kg/m; α = 21×10°C;h – height of molten solder in capillary linking element;γ - coefficient of solder surface tention;θ - angle of solder wettability;α - linear expansion coefficient of solder;ρ– solder density at normal conditions;T– solder temperature in Kelvin degrees at normal conditions;T– temperature of molten solder in Kelvin degrees.

Description

The invention relates to electronic engineering - the design and manufacture of permanent solder joints, widely used in the manufacture of equipment based on microelectronics and semiconductor devices, and specifically to contact nodes on opposite contacts, through which the equipment is assembled from coreless components, including the installation of crystals BIS (chips) in the case, as well as in the composition of multichip modules (MKM).

Prior art

The tendency of development of this area of microelectronic technology is the search for physical and constructive-technological principles that would allow to obtain contact nodes that eliminate the existing obstacles associated with the problems of the formation of a large number (several thousand) identical in their characteristics and reliable contact nodes that connect contacts on LSI crystals with either wiring conductors to external contacts of the LSI housing, or with conductors from different layers of a multilayer switching structure urs m.

Thus, the problems of forming a large number of identical contact nodes are particularly relevant in such areas of the assembly as the installation of LSI crystals in the housing;

installation of LSI crystals in the composition of multichip modules (MKM - electronic unit of unpackaged components - LSI crystals).

Modern LSI crystals as components for assembly are distinguished by a large area of crystals (> 1 cm ² );

a large number of pads (~ 1 thousand);

the location of the contact pads or on the periphery of the crystal (for assembly by the welding method νίτο Vopy assembly technology), or in the form of a matrix over the entire area of the crystal (for assembly by the method of soldering through projections from solder on the contact pads - Ρΐίρ CHE - flip-chip assembly technology) .

Certain perspectives were associated with the technology of contact nodes, in which contacts were connected by extended connecting elements (ESS) in the form of beam ESSs (A. Mazur et al. "Welding and soldering processes in the production of semiconductor devices", Moscow: Radio and Communications, 1991 ., pp. 38-39), pre-formed (by group technological processes) on a thin polyimide (PI) film, in the form of metallized tracks - from contacts on a chip to response contacts on a switching substrate. The ends of the mentioned tracks are designed in such a way that they can be connected by welding with one end to the corresponding contact on the chip, and the other to the contact on the substrate (such a PI-structure is called a "spider"). After the tracks are attached to the contacts and the auxiliary fragments are removed, the pairs of contacts are connected by parallel conductors (beam form - hence the name of the beam ESS) fixed on the surface of the PI structure. Those. in contrast to the classical method of assembly by welding with wires, the SCs in the “spider” cannot be closed together. In addition, all the spider EOLs of future KUs are formed before assembly in the group process in advance, rather than being unwound (from the coil), measured and formed sequentially, one after the other, as is the case with a conventional welding assembly.

Nevertheless, the technology of mounting crystals with the help of PI spiders, representing a variant of the development of the method of assembly by welding wires (ίνίτο Vopy), inherits the main drawbacks of this method:

all contacts on the chip must be located at the edges of the chip (this limits the number of I / O contacts on the chip to linear growth of the chip size);

sequential (non-group) nature of the assembly by welding (this determines the duration of the assembly process, i.e. the probability of assembly machine failure and% rejection);

the possibility of latent defect formation in the chip during welding (this determines the probability of failure in operation, that is, the operational reliability of the equipment containing such chips).

To overcome these drawbacks, the company 1ВМ at the beginning of the 60s of the XX century proposed a method of forming and a device of a contact node (KU) for flip-chip assembly technology (mounting) of an IC chip (chip) on a switching substrate.

The KU flip chip consists of two flat contacts of the same shape and area, one of which is placed on the working surface of the IC chip facing the surface of the switching substrate, and the other contact of the two mentioned flat contacts is placed on the surface of the switching substrate facing the working surface of the crystal, Moreover, the above-mentioned surfaces of the crystal and the switching substrate are plane-parallel, the axes and orthogonal projections of the contours of both contacts are aligned, and the contacts themselves are rigidly interconnected by a jumper from solder in such a way that between the mentioned surfaces of the crystal and the switching substrate, after forming all the contact nodes, a plane-parallel gap is formed, which is usually filled with a hydrophobic elastic insulating material (underderfill), designed to compensate for significant thermomechanical stresses between the crystal and the switching substrate

- 1 010269 during technological impacts and during operation.

Thus, in this method of assembling, the IC chip (CHI is a chip) is turned (turned over) by the working surface to the switching substrate, for which the method itself is called ESr-CHY (flip chip is an inverted chip).

Contact node flip-chip connecting two opposite contacts can be classified as “contact node on opposite contacts” (KU VK).

Components for the flip-chip assembly technology (collection “E1T1ToolsLkketYu 111η 111e No.х1 MSChpsht.” Article “Ιηηοναΐίοη ίη ZigGas Moip1Tespopode”, translation and adaptation by A. Kalmykov) deservedly gained their place on the assembly market due to their obvious advantages, their obvious advantages, their obvious advantages, their translation into the assembly, and their adaptation to A. Kalmykov’s won their place in the assembly thanks to their obvious advantages, their translation, and the adaptation of A. Kalmykov. saving space on the PCB;

low height and low weight;

reducing the cost of materials;

shorter connection lengths, which provide better electrical parameters;

fewer compounds, which reduces the number of potential failures and provides a more efficient distribution of thermal energy.

But, like all the others, this popular technology, in recent years symbolizing the advanced trends of surface mounting technology (MKT), has its drawbacks:

the high cost of the technology of forming spherical protrusions (Vitrk = bumps) on the contact pads of the crystal;

extremely dense PCB layout for a seat for a flip-chip LSI chip, which leads to higher costs for the switching board (substrate);

a large amount of work of technologists on the optimal choice of fluxes and adhesives, depending on the type of the flip-chip component, the substrate and the soldering process;

difficulties in quality control of the process and the results of soldering components of the flip-chip, as well as repairs.

In addition, the issue of the stability of the yield level during the bumping of crystals has not yet been resolved. The assembly cycle time using flip-chip technology can be quite long due to the stages of applying special materials and their curing processes. Special attention should be paid to the distribution of thermal energy to ensure high reliability of the assembly.

The infrastructure of support for the flip-chip technology for the electronic industry is still not as developed as other standard technologies.

There are also the following features in the development of the flip-chip technology:

60% of the total global consumption of flip chips is accounted for by chips with a low number of I / O pins (channels) used in the manufacture of electronic watches and automotive electronics;

followed by chips with an average number of input / output channels used in display drivers, PCMS1A format modules, as well as in larger computer hardware;

and, finally, microcircuits with the number of I / O channels from 2000 and above, which use crystals of high degree of integration and reliability, usually mounted on ceramic substrates.

The use of flip-chip components in portable communications is expected to increase, which is likely to be relevant for Russian electronics in the next few years, as well as in products of computer equipment of a high degree of complexity.

The use of flip chips in products of a high degree of integration and reliability depends strongly on the development of reliable and repeatable technology for their production.

A favorable circumstance in the use of flip-chip technology is a great constructive and technological experience gained in the development and creation of the above-mentioned contact nodes.

However, the contact nodes formed by this technology do not allow direct visual and electrical control of the process and the results of the assembly of the contact node due to the fact that the crystal, facing its contact pads to the substrate, covers all the combined response pads on the substrate. In addition, in such structures there is no natural way out for technological waste from the gap between the substrate and the crystal, which can lead to degradation phenomena in the crystal during operation and reduce the reliability of the functioning of the crystal.

That is, the direct transfer of this experience to the field of microelectronics cannot be performed automatically, without taking into account the special requirements imposed on contact nodes by the specifics of assembly processes in modern microelectronics.

Known microelectronic node containing a semiconductor chip chips, having directed in opposite directions to the upper and lower flat surfaces, with the above-mentioned chip has output contacts,

- 2 010269 located on the periphery of the said lower surface;

a switching substrate having on the surface facing the crystal of the above-mentioned microcircuit, electrically conducting metallized tracks and output contacts, and the said output contacts are connected with the said metallized tracks placed movably relative to the said microcircuit;

an elastic layer located between said substrate and said lower surface of said chip to facilitate moving said metallized tracks, as well as between said electrodes and said chip, said compliant layer consists of a low-modulus material providing independent movement of said electrodes as in the direction parallel to said rear surface of said chip, and in the direction perpendicular to the rear surface of said m kroskhemy;

wire busbars connected to the said microcircuit contacts on the front surface of the said microcircuit, with the said wire busbars running down along the edges of the said microcircuit and connected to the flexible output parts of the substrate adapted to control the impedance of the said flexible output parts located on it;

said substrate includes a polymer dielectric material made in the form of a flexible sheet material selected from the group consisting of polyimide, fluoropolymer, a thermoplastic polymer and elastomers that allow the electrodes to move freely relative to the chip, and the substrate also includes an electrically conductive layer adapted to promote electrical insulation the leads of the electrodes from the microcircuit and provide better control of the impedances of the said lead parts;

said microcircuit contacts define a first center-to-center distance between adjacent microcircuit contacts, and said electrodes determine a second center-to-center distance between adjacent electrodes, with said second center-center distance greater than said first center-center distance;

said substrate has an upper surface facing the microcircuit, and a lower surface facing away from the microcircuit, and said flexible output portions and electrodes can be located both on said upper surface of said substrate and on said lower surface of said substrate, while the substrate includes the holes that pass through it from the said upper surface to the said lower surface, and the electrodes are opened through the said holes and attached to them by means of a binder material;

dielectric sealant covering at least part of said substrate and at least part of said edges and said front and rear surfaces, as well as at least part of said wire wires and at least part of said edges and said front surface of said chip, with sealant is malleable;

thermally conductive layer associated with said front surface of said chip (US Patent No. 5,852,326, IPC H 01B 23/48, 23/52, publ. 1998).

Known contact node containing at least two metallized contact associated with conductive paths placed on the surfaces of the switching layers made on the basis of a dielectric material, combined with each other and interconnected electrically and mechanically conductive bonding material, representing the joint between the contact, made in the form of a metallized flat contact pad associated with conductive paths on the surface of the underlying switching layer, and mating with her counter contact, made in the form of a metallized hole in the layer of dielectric material, with the lower edge of the metallized hole facing the metallized flat contact area on the surface of the underlying switching layer, and its upper edge is connected to the current-carrying paths on the upper surface of the overlying switching layer. In this case, the metallized hole can be made in the form of either a cylinder or a truncated cone, and the metallized contact pad is flat, with a protrusion in the center of the metallized contact pad responding to the metallized hole, which interacts with the counter metallized hole, and is made of electrically conductive material cylinder, cone or ball. In addition, the contact, the reciprocal metallized hole, can be made in the form of a rod fixed in the underlying switching layer, orthogonal to its surface, and inserted into the said metallized hole (international application ¥ O 00/35257 A1, published in accordance with the patent agreement cooperation).

In this contact node, it was possible to substantially eliminate the above-noted drawbacks inherent in the known designs of contact nodes. However, the ever-growing requirements for microminiaturization, on the one hand, and the technical characteristics of MKM, on the other hand, make it constantly important to further improve the design of the contact node, allowing to meet the mentioned constantly growing requirements.

At the same time, a known QA has a pronounced asymmetry with respect to contacts in

- 3 010269 KU: one contact is flat (for example, on a chip or printed circuit board made of fiberglass), and the second contact is in the form of a metallized hole in a film switching structure. And although the need and relevance of such an “asymmetrical” KU is especially significant when creating close-packed equipment based on single- and multi-layer flexible film switching carriers of chips as part of multi-chip modules (MKM), when assembling MKM, there are often problems of efficient binding of pairs of opposite contacts (VC), placed on the counter flat coplanar rigid carriers. A vivid example of solving such a problem (KU on VC) is a KU flip chip and flip chip IC mounting technology (a rigid and fragile plate made of δ мон or another monocrystalline semiconductor), for example, on a rigid switching substrate made of multilayer ceramics.

A contact unit is also known, one of the possible embodiments of which is shown in FIG. 5 patents containing at least two metallized contacts (16, 27) associated with conductive paths placed on the surface of connecting layers made on the basis of a dielectric material and mutually aligned and interconnected by electrically and mechanically conductive bonding material (26), while it is made in the form of an intersection between a contact made in the form of a metallized contact pad (27) associated with conductive paths on the surface of the connecting layer and the corresponding contact, made with a metallized hole (15) in the overlying connective layer, with the lower edge of the metallized hole facing the metallized contact pad on the surface of the underlying contact layer, and the upper edge of this hole is connected with the conductive paths (21) on the upper surface the overlying connecting layer, while the metallized hole has the shape of a cylinder, the upper edge of the metallized hole connected to the conductive paths on top of the connecting layer, forms a metallized rim around the periphery of the edge, the metallized contact pad is flat, the upper and lower edges of the metallized hole have a chamfer.

Another possible embodiment of the said contact assembly, in accordance with the present invention, is shown in FIG. 3 patents in which the contact node contains the first connecting layer (41), having on its surface a conductive path; the second connecting layer (42) applied next to the first connecting layer having a conducting track on its surface; and the metallized hole (43) through the first connecting layer, connected by its inner surface with the conductive path of the first connecting layer; and a metallized contact pad provided on the surface of the second connection layer and connected to the conductive path of the second connection layer, wherein the conductive bonding material (45) is applied in the metallized hole for contacting the inner surface of the metallized hole and the metallized contact pad to form a connection between the first and the second connecting layers, the metallized opening is in the shape of a cylinder (US patent No. 6,104,475).

This patent discloses and protects solutions aimed at ensuring high-quality PCB mounting with ICA leads (for example, ICs in a case with ICA leads) on a circuit board by soldering (BCA / Ba11 Spb Aggau is a matrix array of protrusion contacts made from solder, as a rule, in the form of ball bumps).

From the prior art it is known that arrays of ball BCA contacts (bumps) in the BCA devices are characterized by the following main parameters:

dimensions (height) of bumps (~ 100 microns);

“Step” of bumps (> 200 μm) with their matrix arrangement in a given grid; dimensions of the matrix area with bumps (usually <50x50 mm);

the composition of the materials of the bumps (as a rule, Pb-δη, δη-and Pb-Hell);

melting point of the bump: low-temperature ( <180 ° C) and high-temperature (> 220 ° C), etc.

It is also known that the main problems of mounting printed circuit boards with ICA-outputs, which have not been solved so far, are ensuring the accuracy of combining VSA-protrusions with the response flat contacts;

prevention of "slipping" of BCA-protrusions from the response flat contacts in the process of combining, fixing and soldering;

exclusion of “distortions” of coplanarity of mounted boards when contacts are combined, fixed and soldered;

maintaining a uniform fixed gap between the boards in the process of soldering, when the VSA tabs become liquid;

the elimination of the “spreading” of the ICA protrusions in the molten state, which leads to closures between the ICA leads hidden from visual control, etc.

This patent is aimed at solving the above-mentioned problems of the BCA assembly. An original solution is proposed for pre-fixing the PCB, with those located on the bottom

- 4 010269 in the region of VSL-contacts at a given distance from the surface of the other board (mounting base), which carries on its upper side an array of response flat contacts.

Fixation is achieved using special protrusions-bumps of high-temperature ~ 220 ° C solder, previously formed on the response metallized sites on the board, for example, the carrier ICA contacts, and located along the periphery or inside the array of ICA contacts.

At the first stage of the assembly, a strict fixation of the protrusions-bumps of high-temperature solder relative to the response flat contacts on the bottom board is ensured. At the same time, the gap between the boards is strictly maintained before the main soldering, carried out at a temperature of ~ 180 ° С of the VSabampov array. High-temperature> 220 ° С jumpers from solder on the basis of peripheral holes do not allow the VSA-bumps to "move" from the response flat contacts during the main soldering process at a temperature <180 ° C;

provide a strict gap between the connected boards;

protect low-temperature bump from "spreading" and closure between themselves at low-temperature <180 ° C soldering.

The main purpose of the “flat contact soldered to the metallized hole” type, protected and disclosed in this patent, is the preliminary fixation of two boards against each other with high-temperature jumpers to ensure the quality of the subsequent main soldering of the array of “bump-flat contact” contact arrays at low temperature <180 ° C soldering.

The present invention is not aimed at providing a gap between the soldered boards, but, on the contrary, at providing a “backlash-free” flat contact connection (for example, on an IC chip) with a response contact in the form of a metallized hole (for example, in a flexible switching IC carrier) according to the principle “ soldering a flat bottom to the shell. "

A contact assembly is also known, one embodiment of which is shown in FIG. 2 patents containing at least two metallized contacts associated with conductive paths placed on the surface of the connecting layers made on the basis of a dielectric material and mutually aligned and interconnected electrically and mechanically conductive bonding material (13), while it is made in the form of an intersection between the contact made in the form of a metallized contact pad (31), connected to the conductive paths on the surface of the connecting layer, and the corresponding contact, made in the form of a metallized hole (23) in the overlying connective layer, with the lower edge of the metallized hole facing the metallized contact pad on the surface of the underlying contact layer, and the upper edge of this hole is connected with conducting paths (24) on the upper surface overlying connective layer, while the metallized hole has the shape of a truncated cone, with the lower base of the truncated cones facing the pad on the surface The upper base of the truncated cones is connected with the conductive paths on the upper surface of the overlying connective layer, the upper edge of the metallized hole connected to the conductive paths on the surface of the connecting layer forms a metallized rim along the periphery of the edge, an integrated circuit crystal (41) oriented its metallized pads to the corresponding metallized holes in the overlying connective layer, uses I as a joining layer with respect to metallized contact pads of metallized holes in the overlying bonding layer metallized flat pad; containing further the protrusion (31), interacting with the corresponding metallized hole formed in the center of the metallized contact area relative to the metallized hole, the protrusion has the shape of a sphere, the upper and lower edges of the metallized hole have a facet.

Another possible embodiment of the present invention is shown in FIG. 2 patents, where the contact node contains the first connecting layer (21), having a conducting path on its surface; the second connecting layer (30) applied next to the first connecting layer having a conducting track on its surface; and the metallized hole (23) through the first connecting layer, connected by its inner surface with the conductive path of the first connecting layer; and a metallized contact pad (31) provided on the surface of the second connecting layer and connected to the conductive track of the second connecting layer, while the conductive bonding material (13) is applied in the metallized hole for contacting the inner surface of the metallized hole and the metallized contact pad to form a joint between the first and second connecting layers, the metallized contact pad has a metallized protrusion (11) in the form of a sphere in a wire single binding material (US patent No. 6087597).

The technical solution that is protected in this patent, as well as the technical solution that is protected in the above US patent, is aimed at solving the problems of mounting boards with VSavlyudami on a carrier board with a response flat contacts.

The patent discloses a solution to the same problem of fixing a strict gap between the boards in the process.

- 5 010269 assembly, as in the aforementioned US patent, but only in a different way.

The patent notes that a solid spherical core inserted between a flat contact pad on the bottom plate and a reciprocal metallized hole of conical shape tapering upwards in the top plate partly enters said metallic hole, resting against the conical surface of the metallized hole.

Such a constructive solution and achieved fixing the gap between the upper and lower plates when soldering them with solder, previously placed in the metallized hole and on the surface of a solid spherical core.

Using protrusions of various shapes (spherical, conical, cylindrical), the authors facilitate the alignment of the flat contact area of the lower board, on which the protrusion is pre-placed, with a reciprocal metallized hole in the upper plate, into which the protrusion enters as a guiding element, without resting on any obstacles and without interfering with the upper board, snug against the lower bearing surface.

The invention in accordance with the aforementioned patent is aimed at providing solder columns (bumps) of the same height;

elimination of the compression of the bump during soldering (in order to ensure and fix the gap between the boards); increase the strength of the bump.

As noted above, the claimed group of inventions is not aimed at providing a gap between the soldered boards, but, on the contrary, at providing a “backlash-free” flat contact connection (for example, on an IC chip) with a return contact in the form of a metallized hole (for example, in a flexible switching medium IC) according to the principle of "soldering flat bottom to the shell", which is not achieved in this patent.

The closest in technical essence to the claimed invention in terms of the device and the achieved technical result when using it is a contact node in which the connection of the crystal contacts and the switching substrate is carried out by controlled pressing of the inverted chip to the switching substrate (method C4 = Sop1go11 So11ark CHR Coppesbop), with a contact node (for each pair of opposing contacts) consisting of two flat contacts, one of which is located on the IC chip, is inverted The contact to the switching substrate has a protrusion from the solder, which plays the role of a connecting element, by means of which the said contact is connected with counter-reciprocal contact on the said switching substrate with the solder applied to the contact, and after heating the solder protrusion and solder to the melting temperature, with metered pressure inverted crystal to the switching substrate, between the said contacts is formed of a mechanically strong electrical connection mentioned counter to ntaktov. The gap between the flipped crystal V. Titta1, Eidepe I. Wutakhe \\ '5kg A1ap S. K1orGepk1et, p. 11-136-11-144, LU K1i \\\ 's Asabetk Rišegk 1999].

The C4 assembly method is a development of flip-chip technology aimed at reducing the likelihood of a short circuit between adjacent bumps during the soldering process, by controlled pressing the chip to the substrate (the disadvantages of the flip chip discussed above should be added to the uncontrolled short-circuiting of neighboring solar cells - 80 - 100 micron gap between the chip and the substrate during the soldering process).

Analysis of the advantages and disadvantages of the flip-chip (C4) KU and the flip-chip (C4) of the assembly technology led to the technical solution of this application in the form of a “symmetrical” KU on a VC-type flip chip (C4), but with an ESS not in the form of bumps , and in the form of capillary ESS (SSC).

This solution, like the beam FE, fixed on the PI surface of the "spider" described above, eliminates the possibility of an uncontrolled circuit between the SFCs in the neighboring KU and VC. In addition, the technical solution for this application, while maintaining the main advantages of the flip-chip, multiplies them, as well as eliminates the shortcomings.

DISCLOSURE OF INVENTION

The task, which the claimed group of inventions is intended to solve, is to create such a contact node, the use of which in microelectronic equipment will eliminate the above disadvantages inherent in the existing and used contact nodes, both when assembling multilayer switching structures, and when installing crystals on mounting switching structures i.e. a contact node for mounting the LSI crystals as part of multichip modules and when assembling LSI crystals into the cases.

The technical result, due to the use of a contact node on opposite contacts with a capillary connecting element when assembling microelectronic equipment, is to provide increased reliability of devices by increasing the strength characteristics of the contact node, due to the combination of features of the capillary connecting structure

- 6 010269 elements in an elastic environment of a strong dielectric, as well as high homogeneity of contact nodes made in accordance with the present invention in group assembly, due to the capillary property “compensate” for solder overdose, as well as in resistance to thermal cycles, which is due to the elasticity and strength of the dielectric film - carrier of capillary connecting elements, which is especially effective in structures like "silicon on silicon". In addition, it provides high manufacturability and assembly efficiency due to the capillary effect used in this technology, which can significantly increase the percentage of yield during assembly, as well as reduce the complexity and cost of preparatory operations, because eliminating the need for the formation of precision spherical bumps with characteristic dimensions of 80-100 microns on the contacts of BIS crystals. In addition, after mounting the IC chip onto the switching substrate, the “critical” operation of “injection” into the 80-100 micron gap between the crystal and the substrate is eliminated by a viscous elastic composition, which serves to compensate for stress loads in the “crystal-substrate” structure, during technological and operational thermomechanical effects, due to the difference in thermomechanical deformations of the mentioned structure “crystal-substrate”.

The task laid in the basis of the claimed group of inventions, with the achievement of the above-mentioned technical result in the process of its use in the part of the contact node, is solved by the fact that in a known contact node on counter contacts consisting of at least two flat contacts interconnected electrically and mechanically a connecting element made in the form of a jumper of electrically conductive material, each of these contacts being placed on the flat surface of one of the two coplanar carriers, Kty are oriented towards each other and are aligned with each other relative to a common axis, orthogonal to coplanar carriers and passing through the contact centers, and the gap between the coplanar counter-contact carriers and around the connecting element is filled with a dielectric material, in accordance with the invention capillary, with end flanges, filled with partially or fully electrically conductive bonding material drawn into said capillary in opposing end Acts in which it was pre-placed under the action of capillary forces that occur when the bonding electrically conductive material goes into a liquid state during technological impact during the assembly process of the contact node, with the formation, after the technological impact ceases, a mechanically stable electrically conductive connection between the counter contacts, and the capillary is made in the form of an aperture, the inner surface of which is covered with a wettable electrically conductive bonding material, in a plane a parallel dielectric plate that carries the capillary connecting element and is placed in the gap between said coplanar carriers of opposing contacts, the longitudinal axis of the capillary connecting element passing through the centers of the said opposing contacts orthogonal to the surfaces of the coplanar carriers of the opposing contacts located on the surfaces of the above-mentioned plane-parallel carrier capillary end-to-end coupling element, aligned end-to-end with counter-contacts and mechanically and electrically connected with them by a thin layer of said bonding electrically conducting material

and the fact that the said electrically conductive binder material is made of solder, and the above-mentioned technological impact is thermal;

as well as the fact that the said electrically conductive binder material is gel-like and moistens the inner surface of the capillary connecting element, its flanges and counter-contacts both in the process and after the termination of thermal and other effects;

and the fact that the aforementioned electrically conductive binder material prior to the assembly of the contact nodes is placed inside the capillary hole;

and also the fact that the said counter-contacts are displaced relative to each other in the planes of their carriers, and the longitudinal axis of the capillary connecting element passing through the centers of the contacts is inclined at an angle α <90 ° to the surfaces carrying these contacts;

and the fact that the capillary hole of the connecting element can be made cylindrical;

and also the fact that the capillary connecting element can be made in the shape of a truncated cone, with the smaller socket of the capillary connected to one counter contact, and the larger socket of the capillary connected to another counter contact;

and also the fact that the said counter-contacts are displaced relative to each other in the planes of their carriers, and the longitudinal axis of the capillary connecting element, made in the shape of a truncated cone, passing through the centers of the contacts, is inclined to the planes carrying these contacts at an angle β <90 °;

as well as the fact that the capillary connecting element is made multi-channel;

as well as the fact that the capillary connecting element is a porous structure permeable to an electrically conductive bonding material during the technological impact

- 7 010269 when assembling the contact node;

and also by the fact that the inner surface of the capillary connecting element is made in the form of a surface of revolution relative to the longitudinal axis of the capillary;

and also by the fact that the inner surface of the capillary connecting element is designed so that the cross sections in the plane orthogonal to the longitudinal axis of the capillary are either polygons or smooth closed curves, for example, ellipses;

as well as the fact that technological protrusions with a bonding electrically conductive material are applied on the surfaces of counter contacts, the above mentioned technological protrusions of the contact node enter the capillary partially or completely on its two sides, ensuring mutual self-alignment of said counter contacts and the capillary connecting element in the process contact node assembly;

and also by the fact that the technological protrusion in at least one of the counter contacts of the said contact assembly is made in the form of a spherical projection of a bonding electrically conductive material partially or fully placed in the capillary during the alignment process when assembling the contact assembly;

and also by the fact that both of the mentioned counter contacts have technological protrusions of identical size and shape;

and also by the fact that both of the mentioned counter-contacts have technological protrusions of different sizes and shape, and the associated sockets of the capillary connecting element, are made of different sizes and shape and complementary to the corresponding protrusions of the counter-contacts;

and also by the fact that the above-mentioned plane-parallel carrier of the capillary connecting element is made in the form of a film of elastic material, for example, polyimide;

and the fact that around the capillary connecting element, made in the above-mentioned plane-parallel carrier of a dielectric material, there are holes in the carrier, filled with an adhesive composition that provides bonding of coplanar contact carriers in places free of contacts;

as well as the fact that the above-mentioned plane-parallel carrier of a dielectric material, in which capillary connecting elements are formed, is made in the form of a rigid plate having thermomechanical characteristics identical to the thermomechanical characteristics of counter contacts carriers;

and also the fact that the carrier of capillary connecting elements is made of either glass or oxidized silicon;

and also the fact that the carriers of capillary connecting elements and counter contacts are made of the same material;

and also by the fact that one or both of the mentioned bearing surfaces with opposite contacts are made either of silicon, or of gallium arsenide, or of another semiconductor material, which, in addition to the opposite contacts, have active and / or passive components and current paths on their surfaces, made on the planar technology of microelectronics;

as well as the fact that one of the contact carriers is made in the form of an IC case with ICA-outputs, and the carrier with counter-reciprocal contacts is made in the form of a printed circuit board for surface mounting () of components, and the case with the VSA-terminals interacts with the плат-board through an array of capillary connecting elements made in a film dielectric;

and also by the fact that both carriers of opposite contacts are identical IC bodies with VSA-leads that interact with each other through an array of capillary connecting elements made in a film dielectric;

as well as the fact that one contact carrier is an IC case with ICA outputs, and the counter contact carrier consists of several smaller ICA buildings, the contour of their total area should fit into the contour of the area of the largest oncoming ICA case, and the interaction of all BCA housings should be carried out through a common array of capillary connecting elements made in a film dielectric;

and also the fact that on the surfaces of the plane-parallel carrier of capillary connecting elements there are conductive paths connecting at least two capillary connecting elements to each other;

and also by the fact that on the surfaces of the above-mentioned plane-parallel carrier of the capillary connecting element are placed the power supply and ground tires;

as well as the fact that the carrier of capillary connecting elements is made in the form of a plane-parallel plate of electrically conductive material, covered with a thin layer of insulating material, including the inner surfaces of the holes, the capillary connecting elements, as well as active and / or passive components, conducting paths, are made over the said thin a layer of insulating material;

and also the fact that the conductive basis of the carrier of capillary connecting elements is made

- 8 010269 or from copper, or from aluminum;

and also by the fact that the conductive base of the carrier of capillary connecting elements, made either of copper or aluminum, is used as a ground bus;

as well as the fact that the mentioned carriers of counter contacts, as well as the carrier of capillary connecting elements, placed between the mentioned carriers of counter contacts, are made of different materials having the same thermomechanical characteristics.

A known method of manufacturing contact nodes in the process of mounting integrated circuits in housings with ball points made of solder, made in a given coordinate grid on the contacts of the lower surface of the case (VOL = Bo11 Spy Aggau), on a switching printed circuit board, including applying solder paste to the contact pads of the switching printed the boards responding to ball pins of the IP package;

the combination of the ball pins of the case with the response contacts of the switching circuit board;

heating the soldering area to the melting point of the solder paste, resulting in the formation of contact nodes in which the ball contacts of the housing and the response contacts of the switching circuit board are electrically and mechanically connected, i.e. Ball conclusions are connecting elements in the contact sites, consisting of pairs of mating contacts on the bottom of the IC package and the mounting surface of the circuit PCB | «M | sgos1se1goshs5 Raskadshd Napyook" Paradise II (8s1shsopyis1og Raskadshd) 8esoy Eyyyui, Eyyey Ly: Kao V. Titta1a , Eidepe I. Vuta5 / e \\ ykg A1ap O. K1or1epyet, p. 11-93 - 11-96, Lü Kksheg Asayetiu Ryišchygega 1999].

This method has the following main disadvantages:

difficulties with ensuring equal height of ball conclusions;

difficulties in removing the solder by-products from the narrow gap between the case and the switching circuit board;

difficulties in keeping the ball leads from the solder from spreading in the molten state during soldering with the formation of short circuits between adjacent leads;

difficulties in controlling the process and results of soldering in the narrow gap between the case and the switching circuit board.

To control the results of the installation of the BOA-housing with a large number of ball contacts on the switching printed circuit board, complex and expensive methods of optical and X-ray control are used.

The closest to the claimed group of inventions in terms of the method of manufacturing the contact node to the technical essence and the achieved result in the process of its use is the method of "flip-chip"("invertedcrystal") manufacturing contact nodes in the process of mounting the coreless IC chips on the switching substrate, including on the contacts of the crystal IC thin film layers of metallization and solder;

fabrication of mounting protrusions (bumps) made of solder on the trimmed contacts of the crystal - blanks of connecting elements, from which, in the process of soldering, form the above-mentioned connecting elements between opposing contacts;

solder solder response contacts located on the switching substrate;

the combination of the mentioned bumped contacts placed on the chip, with counter-reciprocal contacts on the switching substrate to their contact, with fixing the combination for the soldering time;

heating the contact zone to the melting point of the solder;

lowering the temperature in the soldering zone before the curing of the above-mentioned solder, resulting in the formation of contact nodes with solder connecting elements, providing electrical and mechanical connection of the contacts of the IC chip and the contacts of the switching substrate;

filling the gap between the IC chip and the switching substrate with an elastic dielectric composition (ZiyoSh), which serves to unload the thermomechanical stresses arising between the IC chip and the switching substrate during subsequent technological actions and in operation, due to the difference in the thermal expansion coefficients of the IC chip and the switching substrate "M | sgoeoscouples5 Pocacción Napocooc", Paradise I (8thIsopicIsPaskasd), Zesopi EyShop, Eyyy lu: Kao V. Titta1a, Eidepe I. Vuta5 / e \\ ykgg A11 O. [YorGenChet, Kaet V. Titta1a, Eidepe I. Vuta5 / e \\ ykgg A11 O. 1-493 - 1-494, Lü Kksheg Asayetu RiYschiega 1999].

The known method has the following undeniable advantages:

group character of the assembly, when all the contacts of the chip are simultaneously attached to the mating contacts of the switching substrate;

relative ease of implementation of the group soldering process.

However, the method has a number of significant drawbacks, the main of which are the following:

on the contacts of the crystal, it is necessary to form precision mounting protrusions (bumps) of the same shape and height, which negatively affects the yield rate, cost and reliability

- 9 010269 of crystals for mounting by the “flip-chip” method;

during the soldering process, there is a probability of “transferring” to the chip, which can lead to merging and short circuits between adjacent solder bumps, which, in turn, makes it necessary to take additional measures that negatively affect the cost of the flip-chip assembly;

the narrow gap between the surface of the crystal and the mounting surface of the switching substrate makes it difficult for solder by-products to escape, which remain in this gap, which adversely affects the reliability of the contact nodes during operation;

the difference in the thermomechanical characteristics of the IC chip and the switching substrate, with a rigid flip-chip design of the contact nodes, leads to large mechanical stresses in the contact nodes, up to their destruction under thermal cyclic loads, which forces the elastic to enter the narrow gap between the crystal and the switching substrate composition (ipbegyp) for unloading stresses, which ultimately negatively affects the complexity and cost of assembly;

The introduction of an ip bag into the gap between the IC chip and the switching substrate is a complex problem when flip-chip assembling large-sized crystals due to the formation of air cavities under the crystal, which negatively manifest themselves in operation.

In the invention it is proposed to use a capillary effect in the manufacture of contact nodes, which almost completely eliminates the disadvantages inherent in known contact nodes and their manufacturing technology.

One of the main tasks of the method of manufacturing a contact node on opposite contacts with a capillary connecting element was to determine the optimal parameters ensuring the stable formation of a capillary connection in the process of manufacturing a contact node.

In the prior art not identified technical solutions associated with the determination of the main parameters that provide the necessary height for raising the melt solder in the capillary, which is a through-metallized hole in the polyimide film (the last coating is electroplated gold of 0.25 μm).

The term “capillarity” refers to interfaces that are sufficiently mobile to form an equilibrium form. The most typical examples are menisci and drops formed by liquids in air or in another liquid.

As is known, capillarity is associated with equilibrium configurations, which are studied in the general system of thermodynamics and deals with the macroscopic and statistical behavior of interfaces, and not the details of their molecular structure.

Free energy per unit surface area is equivalent to surface tension, defined as the force acting per unit length.

The concept of surface free energy and surface tension can be illustrated in the following examples. Consider first a soap film stretched over a wire frame, one side of which is movable, shown in FIG. 1. Each moving element is affected by a force whose direction is opposite to the direction shown by the arrow in the diagram. If the magnitude of this force, referred to the unit of length, is denoted by γ, then the work performed when the movable element is displaced by the distance άχ is equal to

WORK -gNh (1)

Equation (1) can be written as

WORK = γ-yA (2), where άΑ = 1-άχ is the change in surface area.

As a second example, consider the soap film forming the bubble shown in FIG. 2. In this case, it is more convenient to express γ in the form of energy per unit surface. In the absence of fields, for example, a gravitational field, the bubble has a spherical shape, which is characterized by a minimum surface area for a given volume bounded by this surface. Consider a bubble of radius r shown in FIG. 2. The total surface free energy of a bubble is 4πΓ γ. If the bubble radius is reduced by bg, then the change in the surface free energy will be δπτγτ.

Since the surface energy decreases when the bubble is compressed, the tendency to compression should be compensated for by the difference in pressure on the AR film, so that work against pressure AP4pg ² bg was exactly equal to the decrease in surface free energy. In this way

AP4gg ² bg = 8πτγΰΓ (3) or

AR = 2y / g (4)

As a result, we come to an important conclusion: the smaller the bubble, the greater the difference between the air pressure inside the bubble and the outside.

The final state, shown by the dotted lines, is mechanically equilibrium.

It should be noted that usually γ is defined as the surface tension of a single surface.

- 10 010269 section. Therefore, when describing soap or other bilateral films in equations (1) and (2), it is better to use the value 2γ instead of γ.

Equation (4) is a special case of a more general relation — the basic equation of capillarity obtained in 1805 by Jung and Laplace

DD = y (1 / K, + 1 / K ₂ ), (5) where P _s R ₂ - constant radii of curvature.

Equation (5) is the basic equation of the theory of capillary phenomena, and it will be widely used in the future.

In the first approximation, the phenomenon of capillary uplift can be interpreted on the basis of the Young-Laplace equation. If the liquid wets the capillary wall, its surface should be parallel to the wall and, therefore, the entire surface of the liquid should have a concave shape. The pressure difference at the liquid-gas interface is determined by equation (5), and its sign is such that the pressure in the liquid is less than in the gas phase. The authors showed that both radii of curvature (when they have the same sign) are always located on the side of the interface where the pressure is greater.

If the capillary section is round and its radius is not too large, the meniscus has the shape of an almost regular hemisphere (Fig. 3), while both radii of curvature are equal to the radius of the capillary, and equation (5) can be reduced to

DR = 2y / g, (6) where r is the radius of the capillary.

Denote by 11 the height of the meniscus above the flat surface of the fluid (for which DD = 0).

Then, in equation (6), the AP should be equal to the hydrostatic pressure drop in the column of fluid in the capillary. Thus, AP = Ard1, where Ap is the density difference between the liquid and gas phases (p _WHO . - 1.29 kg / m ³ ; rPOS-61 - 8540 kg / m ³ respectively; Ap = rPOS-61, since p _WHO . <<p _Pic-61 ), and d acceleration of free fall.

Now equation (6) can be converted to

The value of a, determined by equation (8), is called the capillary constant. A similar equation can be obtained for a liquid that does not wet the capillary wall, i.e., for a liquid whose contact angle with the walls (contact angle) is not zero, but 180 °. However, in this case we have a capillary decrease, while the meniscus in the capillary is convex, and 1 corresponds to the depth of the decrease of the meniscus (Fig. 4).

In the general case, when the liquid contacts the walls of a circular cylindrical capillary at a certain angle θ, and if the meniscus is still spherical, then, as follows from simple geometric considerations, P ₂ = τ / οοκθ, and since P _one = P ₂ , equation (7) takes the following form:

pdb = 2 soybeans / g. (9)

For an exact mathematical determination of the height of a capillary rise, it is necessary to take into account the deviation of the shape of the meniscus from the spherical, i.e., at each point of the meniscus, the curvature must correspond to AP = Ardu, where y is the excess point above the liquid plane. This condition can be formulated by writing equation (5) at an arbitrary point (x, y) of the meniscus and replacing PP with the corresponding expressions from analytical geometry. It is also assumed that the capillary section is circular and, therefore, the meniscus has the shape of a rotation figure, as shown in FIG. 5. The radius of P1 lies in the plane of the sheet, and P ₂ - in the perpendicular plane. Thus, = y (/ 7 (1 + / Y ² + // x (ΐ + / ² ) 'Ί, (y) where y ^/ = bu / bh and y ^// = b ² y / b ² x

From equation (10) you can get the exact expression for the total weight of the A column of liquid. Let p = y ^/ and therefore have ^// = rbr / bu. Then equation (10) can be written as

2y / a ² = (rdr / bu) / (1 + p ² ) ^3/2 + r / x (1 + r ² ) ^1/2 .(eleven)

Formally, A is determined by the equation

R

UV = 2 Δρ £ π £ хЛЛх, (12) о

which, after replacing y by the corresponding expression found from equation (11), can be transformed into

A = 2πγ / [hfO + /? 2) 3/2 + /? Ίά / (1 + ρ2) 1/2].

The integrand expression of the last equation is equal to the full differential xp / (1 + p ² ) ^1/2 ; with this in mind, respectively, we write the solution of equation (13) in the following form:

- 11 010269 'ν-ί-τ · [χρ / (1 + ρ2) 1/2] ;; ^''(14)

By definition, p = bu / bx, therefore x = r, ρ = 1βφ. where φ = 90 ° -θ. Substituting these limits, we get

XV = 2πΓγοο $ 0. (15)

We note that equation (15) corresponds exactly to the equation that can be written, assuming that the meniscus is “hanging” on the walls of the capillary and the bar is held by the vertical component of the surface tension γοοβθ multiplied by the perimeter of the capillary section of 2pg. Thus, in this case, the mathematical identity of the concepts of surface tension and surface free energy is observed.

It is known that surface tension is due to the fact that molecules on the surface are attracted only to the molecules that are located under them. Therefore, they tend to get stuck inside the liquid. As a result, a thin film with a thickness of 2-3 layers of molecules more dense than the entire liquid of FIG. 6. Another explanation is the following: in the molecules of the surface layer, the potential energy is twice as high as in the molecules inside the liquid. In an effort to occupy a position with the lowest potential energy, the molecules of the liquid on the surface tend to be drawn into the liquid.

Thus, the liquid, under the action of internal forces of molecular attraction, tends to reduce the free surface (that is, the surface in contact with air).

The density of surface energy (surface tension) is the ratio of the work required to increase the surface area to the value of this increment to the area: γ = Δ ^ / YES.

Due to the fact that the surface tension coefficient depends on the temperature, in this case the molten solder, it must be experimentally measured at various temperature values.

By measuring the force T with a precision adhesiometer, which must be applied to increase the surface area of the liquid solder, it is possible to determine the surface tension. To do this, use the wire frame 1, which is immersed in a liquid (Fig. 7).

Since the work is equal to the force of the displacement force, Δ \ ν = ΡΔδ, and the change in surface area on both sides of the frame is ΔA = 2Δδ1, the surface tension can be calculated using the formula γ = Δ8 / 2Δ81, respectively γ = T / 21 [N / m] .

The measurement results are presented in Table. 1. A graph of the dependence of the surface tension of the melt POS-61 on the temperature is shown in FIG. eight.

To measure the wettability angle by soldering the gold surface at different temperatures, an experiment was conducted, which included the preparation of a measuring stand (heating table, measuring system);

preparation of solder doses (cylinder b = 400 μm and 11 = 500 μm) and the gold surface (4x4 mm contact pad).

Solder on the gold surface was melted at different temperatures in vacuum (0.7-6 Pa). After that, on the MII-4 microinterferometer, the wettability angle of the melted drop was measured.

When heated, not only the volume but also the density of the liquid solder changes. To calculate the solder density, use the formula ρ _η = p ₀ / (1 + 3OLT) where p ₀ - solder density under normal conditions, 3 α - linear expansion coefficient.

Thus, the authors obtained all the necessary dependencies and data for calculating the height of the solder lift in the capillary, which taking into account the experimental data obtained takes the following form:

2 - / „- so8b" _I - (1 + Za- (7; -T ₀ )) ^BUT ”- where p ₀ = 8540 kg / m ³ ; α = 21-10 ^{6 o} WITH ^-one ;

- solder lift height in the capillary;

γ is the surface tension coefficient of the solder;

θ is the wetting angle of the solder;

α is the linear expansion coefficient of the solder;

p0 is the solder density under normal conditions;

T ₀ - solder temperature in degrees Kelvin under normal conditions;

T _P - temperature of the molten solder in degrees Kelvin.

Calculations show that with a capillary radius of 10 μm and a temperature change in the range from 493 to 543 K, the surface tension coefficient lies in the range of 0.52-0.46 N / m, the wetting angle varies from 7 to 3 °, the height of the solder lift will be 1500 cm provided that the dose of solder is not limited and the whole ka

- 12 010269 pillar is at a certain temperature.

Thus, the authors solved the problem of ensuring the creation of a capillary connecting element in the manufacture of a contact assembly on opposite contacts, under specific conditions, when a metallized hole made in a film of a dielectric material was used as a capillary.

The problem to be solved in the proposed group of inventions, in terms of the method of manufacturing a contact node on opposite contacts with a capillary connecting element, is to create a method that enables the manufacture of a large number of contact nodes connecting electrically and mechanically two arrays of opposing contacts located on two different carriers ( for example, when mounting IC chips on switching substrates of multichip modules or when mounting ICs in VSA cases on printed circuit boards, I characterize egosya simple realization, low cost and high reliability.

The task underlying the claimed group of inventions, in terms of the method of manufacturing a contact node on opposite contacts with a capillary connecting element, with the achievement of the above-mentioned technical result, is solved by the fact that in the method of manufacturing a contact node on counter contacts with a capillary connecting element including applying from flat contacts of thin-film layers of metallization and solder;

the manufacture of the workpiece connecting element for the said counter-contacts and its service with solder;

serving the soldered flat contact contact;

the combination of the opposite flat contacts with the workpiece of the connecting element relative to a common axis, passing through the centers of the said opposite contacts, prior to their contact, with fixation of the alignment for the soldering time;

heating the zone of contact of the said counter-contacts and the billet of the connecting element to melt the applied solder;

lowering the temperature in the soldering zone to the curing of the above-mentioned solder between the said counter contacts, with the formation of the connecting element of the contact node on the opposite contacts

In accordance with the invention, the billet of the connecting element for opposite contacts is made in the form of a metallized capillary hole in a dielectric film, the outlets of which are limited by end flanges on the surfaces of the above-mentioned dielectric film, and the capillary hole is trimmed by said solder, along with the end flanges, the longitudinal axis of the capillary hole coinciding with the axis of the corresponding flat counter contacts;

said dielectric film, which is the carrier of the said trimmed capillary hole, during the assembly of the contact assembly, is placed between said counter contact carriers so that the longitudinal axis of the said capillary hole passes through the centers of said counter contacts, orthogonal to the surfaces of said counter contact carriers and the trimmed capillary hole;

then bring the carriers of opposing contacts on both sides of the aforementioned carrier of the trimmed capillary hole, along said axis, until the opposing contacts touch the said end flanges of the trimmed capillary hole;

the area between the mentioned carriers of opposing contacts is evacuated to 0.1 atm with simultaneous fixation of the relative position of the carriers of opposing contacts and the carrier of the trimmed capillary hole placed between them;

bring the temperature in the said area to the melting point of the solder, ensuring the rise of the molten solder in the tinned capillary hole from oncoming contacts, also previously mined by the solder mentioned;

in the process and after cooling and curing the solder in the capillary hole, as well as in the gaps between the end flanges of the capillary hole and the corresponding counter-contacts, a capillary connecting element is formed between the said counter-contacts, ensuring rigid fixation of the solder in the metallized capillary hole of the above-mentioned capillary connecting element of the contact node , both in the process of subsequent technological impacts, and in the process of its operation as part of microelectronic oh instrumentation;

the height of the solder lift in the capillary connecting element, in the process of forming the capillary connecting element, is determined by the formula, 2 · γ _η · Οο8θ „· (1 + 3α · (Τ _η -Τ ₀ )) where ρ ₀ = 8540 kg / m ³ ; α = 21-10 ^{6 o} WITH ^-one ;

- the height of the rising melted solder in the capillary connecting element;

γ is the surface tension coefficient of the solder;

- 13 010269 θ - solder wettability angle;

α is the linear expansion coefficient of the solder;

R ₀ - solder density under normal conditions;

T ₀ - solder temperature in degrees Kelvin under normal conditions;

T _P - temperature of the molten solder in degrees Kelvin;

as well as the fact that on said flat contact located on one of the bearing surfaces and / or on the opposite counter flat contact located on the other bearing surface, there are formed oblughennye ledges partially or completely entering the hole of the aforementioned capillary connecting element, which are used in the quality of the mutual basing elements of the mentioned counter contacts and the capillary connecting element;

and also by the fact that the protrusions on the opposite contacts, partially or completely entering the holes of the capillary connecting element, are made in the form of identically molded doses of solder;

and also by the fact that one of the mentioned bearing surfaces with contacts is the surface of an IC chip with contacts, and the other mentioned surface carrying response contacts is a surface with response contacts of the switching substrate.

In the process of assembling contact nodes connecting two arrays of opposing contacts, an array of served contacts of one carrier (for example, on an IC chip), an array of served counter contacts on another carrier (for example, on a switching substrate) and an array of metallized shutters (tubular capillaries) in film The carrier, placed between two arrays of opposite contacts, are combined with each other, approach each other before contact and, after heating to the melting temperature, the melted solder placed on the counter x contacts partially retracted into plated tin-plated holes at both ends by capillary action, forming, after cooling, a secure connection of the two arrays of mating contacts.

The essence of the invention lies in the fact that when interconnected two arrays of opposing contacts located on two parallel (coplanar) carriers, as is the case, for example, when mounting an inverted IC chip (flip chip) on a switching substrate or mounting a packaged IC with ICA - outputs to the printed circuit board, use a mounting gasket made of insulating material, placed between the carriers of the arrays of counter contacts. Metallic trimmed holes are formed in the gasket, located between pairs of interconnecting contacts. Solder doses are pre-applied to the contacts of both arrays. Metallic coated holes become capillaries for the solder placed on opposite contacts at the melting point of the solder. Thus, a strip of insulating material is the carrier of an array of capillary connecting elements for contact nodes interconnecting two arrays of opposing contacts (for example, one system of contacts is on an IC chip, and the response system of contacts is on a switching substrate).

A method of manufacturing contact nodes on opposite contacts through the mounting gasket by means of capillary connecting elements is quite simple and does not require sophisticated equipment with highly qualified service personnel.

The capillary effect ensures a high homogeneity and quality of the joints, as well as a high percentage of the yield of usable contact nodes in the assembly process, ensures a low cost of production.

The method is equally applicable both for mounting crystals as part of single-chip and multi-chip modules, and for mounting ICs in VSA-housings on printed circuit boards.

Brief Description of the Drawings

The invention is illustrated by the graphic materials shown in FIG. 1 shows a frame with a soap film;

in fig. 2 shows a soap bubble;

in fig. 3 schematically shows the capillary uplift;

in fig. 4 schematically shows capillary lowering;

in fig. 5 shows a schematic representation of the meniscus in the capillary as a figure of rotation;

in fig. 6 shows a schematic arrangement of molecules in the surface layer;

in fig. 7 shows the measurement scheme;

in fig. 8 shows a plot of the POS-1 melt surface tension coefficient on temperature;

in fig. 9 shows a symmetrical contact node on opposite contacts with a connecting element in the form of a capillary hole, with end flanges, in a plane-parallel plate of dielectric material (phase alignment);

in fig. 9a - the same symmetrical contact node on opposite contacts with a connecting element in the form of a capillary hole, with end flanges, in a plane-parallel plate made of dielectric material (connection phase);

in fig. 10 - symmetrical contact node on opposite contacts with a connecting element

- 14 010269 in the form of a capillary hole, with end flanges, inside of which, before assembling the contact unit, an electrically conductive bonding material is placed (phase alignment);

in fig. 10a - the same symmetrical contact node on opposite contacts with a connecting element in the form of a capillary hole with end flanges, inside of which before assembling the contact node there is an electrically conductive bonding material (connection phase);

in fig. 11 - contact node on opposite contacts with a connecting element in the form of a capillary hole with end flanges, in which the counter contacts are displaced relative to each other in the plane of their carriers, and the longitudinal axis of the capillary hole passing through the centers of the contacts is tilted at an angle α <90 ° to the surfaces carrying these contacts (phase alignment);

in fig. 11a - the same contact node on counter contacts with a connecting element in the form of a capillary hole with end flanges, in which the counter contacts are displaced relative to each other in the plane of their carriers, and the longitudinal axis of the capillary hole passing through the centers of the contacts is inclined at an angle α <90 ° to the surfaces carrying these contacts (connection phase);

in fig. 12 - symmetrical contact node on opposite contacts with a connecting element in the form of a capillary hole with end flanges, made in the shape of a truncated cone, the smaller socket of which is connected to one opposite contact, and the larger socket is connected to another opposite contact (phase alignment);

in fig. 12a - the same symmetrical contact node on opposite contacts with a connecting element in the form of a capillary hole with end flanges, made in the shape of a truncated cone, the smaller socket of which is connected to one counter contact, and the larger socket is connected to another counter contact (connection phase);

in fig. 13 is a symmetrical contact node on opposite contacts with a capillary connecting element made of multi-channel, while the capillary channels are not electrically interconnected, and each channel has its own end flanges (phase alignment);

in fig. 13a - the same symmetrical contact node on opposite contacts with a capillary connecting element made multi-channel, while the capillary channels are not electrically interconnected, and each channel has its own end flanges (connection phase);

in fig. 14 is a symmetrical contact node on opposite contacts with a capillary connecting element made of multi-channel, while the capillary channels of the multi-channel connecting element are electrically interconnected by common flat electrically conductive contacts made in the form of end flanges placed on the surfaces of a plane-parallel plate of dielectric material in which mentioned multi-channel capillary connecting element (phase alignment);

in fig. 14a - the same symmetrical contact node on opposite contacts with a capillary connecting element made multi-channel, while the capillary channels of the multi-channel connecting element are electrically interconnected by common flat electrically conducting contacts made in the form of end flanges placed on the surfaces of a plane-parallel plate of dielectric material in which made the above-mentioned multi-channel capillary connecting element (connection phase);

in fig. 15 - symmetrical contact node on opposite contacts with the connecting element, which is a porous structure, permeable to an electrically conductive bonding material in the process of technological impact (phase alignment);

in fig. 15a - the same symmetrical contact node on opposite contacts with the connecting element, which is a porous structure filled with an electrically conductive bonding material in the process of technological impact (connection phase);

in fig. 16 - symmetrical contact node on opposite contacts with a capillary connecting element, in which technological projections are made on the surfaces of counter contacts, with a bonding electrically conductive material applied to them, while the mentioned technological projections of the contact node enter into the capillary hole, partially or fully, from both the sides, ensuring mutual self-alignment of said counter contacts and the capillary connecting element in the process of assembling the contact node (phase of alignment);

in fig. 16a - the same symmetrical contact node on opposite contacts with a capillary connecting element, in which technological ledges are made on the surfaces of opposite contacts, with a bonding electrically conductive material applied to them, while the mentioned technological tabs of the contact node enter into the capillary hole, partially or completely, both sides, ensuring mutual self-alignment of the mentioned counter contacts and the capillary connecting element in the assembly process of the contact node (phase of connection eniya);

in fig. 17 - symmetrical contact node on opposite contacts with a capillary connecting element, in which technological projections are made on the surfaces of counter contacts, at least at least one of the projections are made in the form of a ball of an electric bonding

- 15 010269 conductive material, partially or fully placed in the capillary hole (phase alignment);

in fig. 17a - the same symmetrical contact node on opposite contacts with a capillary connecting element, in which technological projections are made on the surfaces of opposite contacts, at least at least one of the projections are made in the form of a ball of a bonding electrically conductive material, partially or completely, placed in capillary orifice (connection phase);

in fig. 18 is a symmetrical contact node on opposite contacts with a capillary connecting element, in which a plane-parallel plate of dielectric material is a carrier of holes, one of which, located between the opposite contacts, is a capillary connecting element for these counter contacts, and the other holes that are not between counter-contacts, impregnated with adhesive (adhesive) compositions intended for gluing coplanar contact carriers in places free of contact ktov (phase of combination);

in fig. 18a - the same symmetrical contact node on opposite contacts with a capillary connecting element, in which a plane-parallel plate of dielectric material is a carrier of holes, one of which, located between the opposite contacts, is a capillary connecting element for these counter contacts, and other holes that are not are between the opposite contacts, impregnated with an adhesive (adhesive) composition intended for gluing coplanar contact carriers in places free from contacts (compound phase);

in fig. 19 - the main stages of preparation, combination and connection (assembly) of components of a KU into a single device - a contact node on opposite contacts with a capillary connecting element (KU on a VC with a SEC);

in fig. 20 is a diagram of the basic photolithography process;

in fig. 21 is a diagram of the basic technological process of manufacturing metallized holes in a polyimide film;

in fig. 22 is a photo of an experimental sample of an assembly machine for assembling a VU on a VC with a SEC;

in fig. 23 is a block diagram of an experimental sample of an assembly machine for assembling a VU on a VC with an SSC;

in fig. 24 - photo of the sample single-crystal module OKM-1600 on the basis of a test chip with dimensions of 1x1 cm with a matrix of 40x40 = 1600 contacts assembled using an experimental sample of an assembly machine for assembling a VC on a VC with SEC;

in fig. 25 - photo of the sample of the multichip module MKM-3200 based on 8 test chips with dimensions of 1x1 cm with a matrix of 20x20 = 400 contacts assembled using an experimental sample of an assembly machine for assembling KU on a VK with SCC;

in fig. 26 is a table of the dependence of the surface tension coefficient of the POS61 solder melt on the temperature in the range of 493-543 K.

The preferred embodiment of the invention

One of the many possible embodiments of a contact assembly on opposite contacts with a capillary connecting element, shown in FIG. 9 (phase alignment), contains contact 1, placed on one of the coplanar carriers, for example, upper carrier 2, for which, for example, a δι-crystal with active components, contact 3, placed on the second coplanar carrier, for example, the lower carrier 4, for which, for example, a δί-PCB switching substrate can be used. A plate of dielectric material, for example polyimide film 5 with a metallized hole 6 formed in it, is placed between the mentioned coplanar carriers 2 and 4 of the contact node. On the top carrier 2, which is used, for example, a silicon crystal, there is a conductive path 7, for example, aluminum, connected to contact 1. A similar conductive path 8 is applied on the lower carrier 4 and connected to contact 3. The formation of one of the opposite contacts, for example, 1, is completed by applying to dose conductive binder material 9 (solder). Similarly, the second counter contact 3 is formed by applying a dose of a bonding electrically conductive material 10 (solder) on it. The coating of the same binder material 12 is applied to the metallized surface 11 of the hole 6 and the end flanges 13 and 14 formed at the outlets of the hole 6 made in the dielectric film 5. Thus, the above describes the implementation of the main elements of the contact node on the opposite contacts with capillary connecting element. Further, these symbols will be used to describe individual features and various embodiments of this contact point.

So, in the phase of alignment (Fig. 9), pins 1 and 3, arranged opposite to each other - on the top 2 and bottom 4 carriers, respectively, are aligned relative to the common axis A-A between themselves and the hole 6 in the dielectric film 5. On the said contacts 1 and 3 is a bonding electrically conductive material 9 and 10, respectively. On the inner metallized coating 11 of the hole 6 and the said end flanges 13 and 14 there is a similar bonding electrically conductive material.

- 16 010269 terial 12. Next is the connection phase.

In the connection phase (Fig. 9a), contacts 1 and 3 converge towards each other until they come into contact, respectively, with the upper and lower end flanges of the metallized opening 6. At this moment, the contact area 1, 3 and the opening 6 with the end flanges 13 and 14 are exposed to technological impact (for example, temperature effect before melting of a binder of electrically conductive material - solder), as a result of which the metallized hole 6 becomes a capillary for a binder of electrically conductive material, which in the process Cesky impact is drawn into the capillary with both contacts 1 and 3 by capillary action. After the termination of the technological impact of the binding electrically conductive material in the capillary, as well as between the flanges and counter contacts hardens. This forms a contact node consisting of two contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element 6, filled with hardened bonding electrically conductive material.

Contact node on the opposite contacts with the capillary connecting element can be made somewhat differently than described above. Thus, doses of a bonding electrically conductive material 9, 10 may not be placed on contacts 1 and 3 before assembling the contact assembly, but directly inside the metallized opening 6. Such an embodiment of the contact assembly is shown in FIG. ten.

In the phase of alignment (Fig. 10), pins 1 and 3, arranged opposite to each other - on the top 2 and bottom 4 carriers, respectively, are aligned relative to the common axis A-A between themselves and the hole 6, with the end flanges 13 and 14, in the dielectric film 5, filled with a bonding electrically conductive material 15.

In the connection phase (Fig. 10a), contacts 1 and 3 converge towards each other until they come into contact with the upper and lower end flanges 13 and 14 of the metallized hole 6. At this moment, the contact zone 1, 3 and the hole 6 are subject to technological influence (for example, temperature effects the melting of a binder of electrically conductive material - solder), as a result of which the metallized hole 6 becomes a capillary for a binder of electrically conductive material 15, which in the process of technological impact wets the contact Acts 1 and 3. At the same time, capillary forces do not allow the mentioned bonding electrically conductive material 15 to spread from the capillary 6 beyond the limits of the wetted contacts 1 and 3 and the said end flanges 13 and 14. After the termination of the technological effect, the bonding electrically conductive material in the capillary, as well as between the mentioned end flanges and counter contacts hardens. This forms a contact node consisting of two contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element filled with hardened bonding electrically conductive material.

In a very diverse practice of manufacturing microelectronic equipment, there are quite common cases when it is necessary to perform a contact node in which the counter contacts are displaced relative to each other. Such an embodiment of the contact assembly on opposite contacts with a capillary connecting element is shown in FIG. eleven.

In the phase of alignment (Fig. 11), pins 1 and 3, arranged opposite to each other - on the top 2 and bottom 4 carriers, respectively, are aligned relative to the common axis A-A between themselves and the inclined hole 6, with the end flanges 13 and 14, in the dielectric film 5. At the aforementioned contacts 1 and 3 there are doses of a bonding electrically conductive material 9 and 10, respectively. On the metallized coating 11 of the hole 6 and the said end flanges 13 and 14 is the same bonding electrically conductive material 12.

In the connection phase (Fig. 11a), contacts 1 and 3 converge towards each other until they come into contact with the upper and lower end flanges 13 and 14 of the metallized hole 6. At this moment, the contact area 1, 3 and the hole 6 is exposed to technological impact (for example, temperature effects prior to melting of a bonding electrically conductive material - solder), as a result of which the metallized hole 6 becomes a capillary for the bonding electrically conductive material, which during technological action retracts into Pillyar with both contacts 1 and 3 by capillary action. After the termination of the technological impact of the binding electrically conductive material in the capillary, as well as between the mentioned end flanges and counter contacts hardens. This forms a contact node consisting of two contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element filled with hardened bonding electrically conductive material.

In accordance with the present invention, it is envisaged that the contact node can be made on opposite contacts with a capillary connecting element of various shapes and configurations. So in FIG. 12 shows a contact node on opposite contacts with a capillary connecting element made in the shape of a truncated cone.

In the phase of alignment (Fig. 12), pins 1 and 3, arranged opposite to each other - on the top 2 and bottom 4 carriers, respectively, are aligned relative to the common axis A-A between themselves and the tapered bore 6 with the end flanges 13 and 14 in the dielectric film 5. At the same time the smaller races

- 17 010269 the capillary tubes are connected to one of the contacts, and the larger socket of the capillary is connected to the other counter contact. On the above-mentioned contacts 1 and 3 is a binder of electrically conductive material 9, 10, respectively. On the inner metallized coating 11 of the hole 6 and the end flanges 13 and 14 there is the same bonding electrically conductive material.

In the connection phase (Fig. 12a), contacts 1 and 3 converge towards each other until they come into contact with the upper and lower end flanges 13 and 14 of the metallized hole 6. At this moment, the contact area 1, 3 and the hole 6 with the end flanges 13 and 14 undergo technological impact (for example, temperature effects before melting a binder of electrically conductive material - solder), as a result of which the metallized hole 6 becomes a capillary for a binder of electrically conductive material The action is drawn into the capillary from both contacts 1 and 3 by the action of capillary forces. After the termination of the technological impact of the binding electrically conductive material in the capillary, as well as between the mentioned end flanges and counter contacts hardens. This forms a contact node consisting of two contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element filled with hardened bonding electrically conductive material.

FIG. 13 shows a contact node on opposite contacts, in which the capillary connecting element is made multi-channel.

In the phase of alignment (Fig. 13), pins 1 and 3, arranged opposite to each other - on the top 2 and bottom 4 carriers, respectively, are aligned relative to the common axis A-A, between themselves and the end flanges 13 and 14 of the group of capillary channels 6 in the dielectric film 5. On the aforementioned contacts 1 and 3 is a binder of electrically conductive material 9, 10, respectively. On the inner metallized coating of the channels 6 and on the end flanges 13 and 14 there is a similar bonding electrically conductive material.

In the connection phase (Fig. 13a), contacts 1 and 3 converge towards each other until they come into contact with the upper and lower end flanges 13 and 14 of the metallized channels 6. At this moment, the contact area 1, 3 and the holes 6 are subject to technological influence (for example, temperature impact before melting the bonding electrically conductive material - solder), as a result of which the metallized channels 6 become capillaries for the bonding electrically conductive material, which in the process of technological influence is drawn into the capillary bright channels from both contacts 1 and 3 under the action of capillary forces. After the termination of the technological impact of the binding electrically conductive material in the capillaries, as well as between the mentioned end flanges and counter contacts hardens. A contact node is formed, consisting of two contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element consisting of several channels that are not electrically interconnected and filled with solidified bonding electrically conductive material.

Unlike the previous version, the contact node on opposite contacts with the capillary connecting element can be designed in such a way that the capillary channels of the multichannel connecting element are electrically interconnected by common flat electrically conductive contacts in the form of common end flanges placed on the surfaces of the dielectric film in which mentioned multi-channel capillary connecting element. Such an embodiment of the contact assembly is shown in FIG. 14.

In the alignment phase (Fig. 14), pins 1 and 3, arranged opposite to each other - on the top 2 and bottom 4 carriers, respectively, are aligned with respect to the common axis A-A between themselves and the group of capillary channels 6, with common end flanges 13 and 14, in the dielectric film 5. At the above-mentioned contacts 1 and 3 there is a bonding electrically conductive material 9, 10, respectively. On the inner metallized coating of the channels 6 and on the mentioned end flanges 13 and 14 there is the same bonding electrically conductive material.

In the connection phase (Fig. 14a), contacts 1 and 3 converge towards each other until they come into contact with the upper 13 and lower 14 end flanges of the capillary channels 6 on the surfaces of the film 5 common to the metallized channels 6. At this moment, the contact area 1, 3 and the holes 6 is exposed to technological impact (for example, temperature effects before melting the bonding electrically conductive material - solder), as a result of which the metallized channels 6 become capillaries for the bonding electrically conductive material, which in percent sse exposure process is drawn into the capillaries with both contacts 1 and 3 by capillary action. After the termination of the technological impact of the binding electrically conductive material in the capillaries, as well as between the mentioned end flanges and counter contacts hardens. A contact node is formed, consisting of two contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element consisting of several channels filled with hardened bonding electrically conductive material.

The contact node on the opposite contacts with the capillary connecting element can be designed in such a way that the connecting element is a porous structure that is permeable to the electrically conductive bonding material during the process impact. Ta

- 18 010269 This embodiment of the contact node is shown in FIG. 15.

In the phase of alignment (Fig. 15), pins 1 and 3, arranged opposite to each other - on the top 2 and bottom 4 carriers, respectively, are aligned relative to the common axis A-A between themselves and the porous structure 15 in the dielectric film 5. On the said contacts 1 and 3 is a bonding electrically conductive material 9 and 10, respectively. The porous structure 15 is wettable and permeable to a binder of electrically conductive material during technological exposure.

In the connection phase (Fig. 15a), contacts 1 and 3 converge towards each other until they come into contact with the upper and lower ends of the porous structure 15. At this moment, the contact area 1, 3 and the porous structure 15 is exposed to technological impact (for example, temperature effects before melting the binder electrically conductive material - solder), as a result of which the porous structure 15 becomes wettable and permeable to the bonding electrically conductive material, which in the process of technological impact is drawn into the porous structure Pattern 15 from both contacts 1 and 3 under the action of capillary forces. After the termination of the technological impact of the binding electrically conductive material in the porous capillary structure 15 is solidified. This forms a contact node consisting of two contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element filled with hardened bonding electrically conductive material.

Another embodiment of the contact node on opposite contacts with a capillary connecting element is a contact node in which technological protrusions with a bonding electrically conductive material are applied to the surfaces of the opposite contacts. The above-mentioned technological protrusions of the contact unit enter the capillary partially or completely on its two sides, ensuring mutual self-alignment of the said opposing contacts and the capillary connecting element during the assembly process of the contact unit. This embodiment of the contact node is shown in FIG. sixteen.

In the alignment phase (FIG. 16), the technological protrusions 16 and 17 on contacts 1 and 3, respectively, coated with a bonding electrically conductive material 9 and 10, respectively, approach each other towards contact with the upper and lower end flanges 13 and 14 of the metallized hole 6 in the film carrier 5 and are aligned with each other and the metallized hole 6 relative to the common axis A-A.

In the connection phase (Fig. 16a), the area of the technological protrusions 16 and 17 and the metallized hole 6 is exposed to technological impact (for example, temperature effects before melting the bonding electrically conductive material - solder), as a result of which the bonding electrically conductive material is drawn into the hole 6c during the technological impact technological protrusions 16 and 17 under the action of capillary forces. After the termination of the technological impact of the binding electrically conductive material in the capillary structure, as well as between the mentioned end flanges 13 and 14 and the opposite contacts hardens. This forms a contact node consisting of two contacts 1 and 3 interconnected electrically and mechanically by a capillary connecting element filled with hardened bonding electrically conductive material, and the formed contact node is obtained reinforced technological protrusions 16 and 17, which significantly increases the strength of the contact node.

The above-described variant of the contact assembly can be varied in terms of execution as follows: the technological protrusion in at least one of the opposing contacts of the said contact assembly is a ball of bonding electrically conductive material partially or fully placed in the metallized hole. Such a contact assembly is shown in FIG. 17

In the alignment phase (Fig. 17), the technological protrusions 18 and 19, made in the form of balls of bonding electrically conductive material formed on the contacts 1 and 3, approach each other towards each other before contact with the upper and lower end flanges 13 and 14 of the metallized opening 6 in the film the carrier 5 and are aligned with each other and the metallized hole 6 relative to the common axis A-A.

In the connection phase (Fig. 17a), the area of the technological protrusions 18 and 19 and the metallized hole 6 is exposed to technological impact (for example, temperature effects before melting the bonding electrically conductive material - solder), as a result of which the bonding electrically conductive material is drawn into the hole 6 from the technological tabs 18 and 19 under the action of capillary forces. After the termination of the technological impact of the binding electrically conductive material in the capillary structure hardens. This forms a contact node consisting of two contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element filled with hardened bonding electrically conductive material, and a ball 19 at the contact

3

A variant of a contact assembly on opposite contacts with a capillary connecting element, which has an increased tightness and mechanical strength, is shown in FIG. 18.

In this contact node, a plane-parallel plate of dielectric material 5 is

- 19 010269 carrier holes, one of which 6, with end flanges 13 and 14, located between the opposing contacts 1 and 3, is the capillary connecting element for these opposing contacts, and the other holes 6a, which are not between the opposing contacts, are impregnated with glue ( adhesive) composition 20, intended for bonding coplanar carriers 2 and 4 of the mentioned counter-contacts in places free from the contacts on these carriers.

In the phase of alignment (Fig. 18), a pair of mating contacts 1 and 3, arranged opposite to each other - on the top 2 and bottom 4 carriers, respectively, are aligned with each other and the capillary hole 6, with the end flanges 13 and 14, in the said dielectric plate 5 relative to the common axis A2A2. On the above-mentioned contacts 1 and 3 there is a bonding electrically conductive material, respectively 9 and 10. On the inner metallized coating of the opening 6, as well as on the mentioned end flanges 13 and 14, there is the same bonding electrically conductive material.

In the connection phase (Fig. 18a), the pairs of mating contacts 1 and 3 converge towards each other prior to contact with the upper and lower ends of the metallized holes 6, and the adhesive composition 17 placed in the remaining holes 6a comes in contact with the bearing surfaces 2 and 4, free from oncoming contact. At this point, in the area of contacts 1, 3 and holes 6 and 6a, the technological impact is activated, the nature of which is such that the metallized hole 6 becomes a capillary for a bonding electrically conductive material, which during the technological impact is drawn into the capillary 6 from opposite contacts 1 and 3 under the action capillary forces. After the termination of the technological impact, the bonding electrically conductive material in the capillary, as well as between the mentioned end flanges and counter-contacts, hardens, and the adhesive composition 20 fills all remaining cavities between carriers 2 and 4 and also hardens. As a result of the technological impact, a contact node is formed, consisting of opposing contacts 1 and 3, interconnected electrically and mechanically by a capillary connecting element 6 filled with hardened bonding electrically conductive material, and the contact carriers 2 and 4 are hermetically and firmly glued.

The following describes the technological process of manufacturing a contact node (CI) on opposite contacts (CK) with a capillary connecting element (CCE) with the following general characteristics (for example, CI in Fig. 9): 2 - contact carrier 1 (silicon IC chip); 4 - contact carrier 3 (silicon switching substrate); 1 and 3 - contacts (contact pads) of A1 with dimensions of 70x70 microns with metallization layers (adhesive layer T1 ~ 0.1 microns thick, conductive Cu layer ~ 1.0 microns, protective layer N1 ~ 0.1 microns, solder 9, 10 8ηΒί ~ 15-20 microns - height at the upper edge of the meniscus); 5 - carrier of the capillary hole (polyimide film 50 μm thick); 6 - capillary hole (with an inner diameter of 20-30 microns), as well as 13 and 14 - the upper and lower end flanges of the capillary hole 6 with metallization layers (adhesive layer from Cr ~ 0.1 µm, conductive layer from Cu ~ 3-5 micron, protective layer of N1 ~ 0.1 micron, solder 12 of 8ηΒί ~ 3-5 micron, outer diameter of flanges ~ 70 micron, width of flanges ~ 10 micron).

The technological process of manufacturing KU (Fig. 9) includes two preparatory technical processes (preparation of contacts on carriers 2 and 4, and technical processes for contacts 3 and 4 are the same, and preparation of carrier 5 of a capillary hole 6 with end flanges) and technical processes of assembling KU from prepared mentioned parts (Fig. 19).

The processing of contacts on the IC chips and the switching substrate are group (that is, all contacts 3 or 4 of all carriers 1 and 2, respectively, placed on silicon wafers are processed simultaneously).

In the process of preparation of contacts, an important operation is the procedure of plasma-chemical cleaning of contact pads from A1 from A1 ₂ ABOUT ₃ (for example, on the installation "Trion"; a detailed description of the installation: OD Parfyonov, "Technology chips", publishing house Higher School, 1986, pp. 226-227).

Then, on the mentioned installation “Trion”, in the same vacuum pumping cycle, the metallization layers are deposited in succession: adhesive layer T1 (0.1 μm), conductive layer Cu (1.0 μm) and protective layer N1 (0.1 μm).

After removing the plates from the cleaning / sputtering unit, standard photolithography is performed on them with the opening of windows, in a graded photoresist, over dusty contact pads in accordance with the diagram of FIG. 20 (OD Parfyonov, “Technology of Microcircuits”, publishing house Higher School, 1986, pp. 90-112).

Then, in the opened windows, a galvanic build-up of solder (8ηΒί, 15 μm) for metallization (N1) is performed.

After removing the photoresistive mask and washing the plates, chemical etching of thin layers of metallization is carried out in the reverse order of deposition (see Section 1.2. Above). At the same time, the metallization layers under galvanically increased solder remain on the contact pads, since the solder plays the role of a mask.

After reflow of the solder 8η оп (at T ~ 220 ° C) to give the solder lugs of the same shape a convex meniscus ~ 20 μm in height, the preparation of contacts 1, 2 is completed.

After dividing (scribing) plates into crystals and switching substrates (for example,

- 20 010269 using semi-automatic scribing "Almaz-M" (OD Parfyonov, "Chip Technology", publishing house Higher School, 1986, p. 254), is laying the crystals and substrates in the process packaging to move to the assembly site .

The technological process of manufacturing and servicing of metalized holes with solder, with end flanges, in a polyimide film is carried out according to the scheme shown in FIG. 21 (I. N. Vozhenin et al., “Microelectronic Apparatus for Unpackaged Integrated Circuits,” Moscow, publishing house Radio and Communications, 1985, p. 154).

Group manufacturing of precision holes in polyimide was carried out using double-sided chemical etching in KOH solution. The coordinates of the holes and their shape are specified by photomasks in the photolithography process as shown in FIG. 20. As a carrier of capillary holes, a Karimop-200N polyimide film manufactured by Bi Ροίηΐ (USA) with a thickness of 50 μm was used.

It should be noted that there are other ways of forming holes in the PI film in given coordinates, for example, laser drilling. In contrast to the group process of chemical etching, laser drilling is a sequential procedure that requires sophisticated equipment for its implementation.

Metallization of the holes and surfaces of the polyimide film was carried out on a UVN71-P1 unit, modified for plasma chemical cleaning and magnetron sputtering of two metals in a single vacuum pumping cycle. The warm-up time in the vacuum chamber is 25 minutes, which makes it possible to reach 150 ° C, the pressure of argon working gas during plasma chemical cleaning is 4.9-10 ^-2 Pa, and during the deposition of metallized layers, 2.7-10 ^-one Pa.

Polyimide substrates were metallized with copper of 99.9% purity. The resistivity of the obtained copper films did not exceed 2.0 µOhm / cm, and the adhesion was at least 400 g / cm.

Sprayed on both surfaces of the film and in the holes, the Cr – Cu – Cg layers will serve as one of the electrodes during electrochemical (galvanic) deposition and buildup of Ci-Νί-δηΒί in the openings 6 and on their end flanges 13 and 14. After 2-sided photolithography according to the scheme in accordance with FIG. 20 and the opening of a photoresist mask of round-shaped windows (~ 70 µm in diameter) on both sides of the holes, the Cr was vented to the C layer inside the holes and within the boundaries of the formed end flanges.

Then, in accordance with the scheme of FIG. 21, electrochemical (galvanic) deposition of pure copper (~ 3 µm), a protective layer N1 and subsequent deposition of a solder layer (δηΒί ~ 5-7 µm) was performed on the surfaces of the holes and the flanges mentioned above, freed from Cr.

After removing the photoresist on both sides of the PI film, chemical etching of the CgCi-Cg layers is performed on both sides of the PI carrier 5. At the same time, the solder layer δηΒί in the holes and on the flanges, playing the role of a protective mask for the underlying layers of Cr-Ci-Νί, protects these layers that provide high adhesive resistance of capillary holes with end flanges on a PI carrier.

After washing, cutting and cutting PI carriers (there may be several of them on the same PI substrate), they are visually and electrically monitored (for short circuits and breaks), then placed in process packaging and delivered to the CU assembly.

The manufacturing process of the contact unit (CU) on opposite contacts with the capillary connecting element is completed by the process of assembling the CG method of vacuum soldering.

Since the vacuum soldering method was used mainly for the assembly of polyimide multilayer printed circuit boards and the available equipment did not meet the requirements of the KU assembly for this application (there was no system for combining contacts 1 and 2 with a capillary hole 6), the applicants developed, manufactured and tested (for The test structures created for this purpose are an experimental model of an assembly machine that demonstrated the feasibility of the technical solutions disclosed in this application. The photo of this sample is shown in FIG. 22. FIG. 23 shows a block diagram of said assembly machine.

A sample of the assembly machine was created on the basis of a desktop installation (907.250 from PK1T8SN, Germany) for precision alignment of the flip-chip and ΒΟΑ components and their mounting on printed circuit boards (main characteristics: max dimensions of components - 48x48 mm; max dimensions of switching substrate - 280x230 mm; ± 5 µm alignment accuracy).

Chip 12 (Fig. 23) is fixed, with the contacts down, with a vacuum suction 23 on the upper heater 7 with a temperature sensor 27 under the cover 11 of the vacuum microchamber, which is formed when the cover 11 is lowered to the ground on the ground surface of the base 14 containing the lower heating element 25 with the sensor temperature 28, which is installed through the base pins, with the contacts up, the switching substrate 9, and the PI carrier of the capillary holes is placed on it through the base pins. At the time of combining the chip 12 and the substrate 9, the chip 12 with the upper part 11 rises up so that between the chip 12 and the substrate 9 you can freely enter a prism 8 (on a swivel bracket - not shown in the block diagram) of the optical visual control system, through through the camera 21 and the TV monitor 22, combining the upper and lower counter contacts.

- 21 010269

The combination of oncoming contacts is performed manually as follows. The base 14, located on the coordinate table 18, moves in the plane with the X and Υ manipulators. The rotation of the chip around the axis is carried out by the manipulator. By controlling the X, Υ and Ζ manipulators, and controlling on the color screen the mutual displacement of the chip contacts and the PI carrier holes of capillary holes (already aligned with the substrate contacts on the base pins), the operator achieves (in a fraction of a minute) the full alignment of the chip contacts with the response capillary holes , spaced vertically at ~ 10 cm (the height of the inserted prism is ~ 8 cm).

Next, the operator removes the prism from the area between the cover 11 and the base 14 of the vacuum microchamber and all subsequent operations are performed automatically under the control of the controller 17.

Using a precision screw 6, the bracket 5 with the chip 12, under the control of the controller 17, is lowered until it touches the PI carrier without disturbing the previous alignment, with a soft fixation of the chip in this position for the soldering time. Then, part 11 is lowered until the vacuum microcamera is closed and, according to a given program, the vacuum pumping pump (not shown in Fig. 23) and heaters 27 and 28 are turned on, which provide the required temperature-time soldering in the “chip-PI carrier-substrate” structure ". Upon completion of soldering, the microcamera is vacuumized, the chip is disconnected from the suction cup, node 5 with cover 11 rises, the substrate with the soldered test chip 12 is removed from the base pins and the installation is ready for a new cycle that lasts ~ 1 min.

The positioner 29, 30 and 31 of the stepper motor 1, the gearbox 2 of the screw 6 and the stepper motor 3, respectively, are connected to the controller unit 17, as well as the control unit for 16 stepper motors 1, 3 and heaters 7 and 25, which also controls the micropump unit 15.

The described experimental assembly machine made it possible to obtain test samples of single-chip modules (OCM) with 1x1 cm test chips, having 400 contacts (in a matrix of 20x20 contacts) and 1600 (40x40) contacts (the photo of OKM-1600 is shown in Fig. 24).

In addition, samples of a multichip module (MCM) with dimensions of 35x70 mm for 8 test chips 1x1 cm, having 400 contacts (in a matrix of 20x20 contacts) —a total of 8x400 = 3200 CG on counter contacts with capillary connecting elements (photo in Fig. 25) were obtained. ).

Industrial Applicability

Performing a contact node with a capillary connecting element in accordance with the present invention can significantly improve the quality characteristics of the contact node: strength (tear, vibration, shock, acceleration), uniformity of characteristics during group assembly process (reproducibility), stability in time and during operation (reliability), stability in the range of temperatures and at thermal cycles, compactness (density of installation), influence on speed. In addition, this implementation of the contact node also provides a significant reduction in the cost of its manufacture by reducing: material intensity, reducing the price of materials (excluding the use of scarce and precious materials), labor input of preparatory operations, ensuring manufacturability, testability, environmental friendliness of preparatory and finishing procedures and reagents.

Reducing the complexity and cost of preparatory operations occurs by eliminating the need to form precision spherical bumps on the contacts of the IP crystals.

High manufacturability and high yield in the assembly of contact nodes is ensured by the use of capillary forces in the manufacturing process of contact nodes, which exhibit high efficiency in such compounds.

High uniformity in the process of manufacturing contact nodes due to the property of the capillary to "compensate" for solder overdose on counter contacts.

The increase in the strength of the contact node and the resistance to thermal cycles (especially in systems like "silicon on silicon") are due to the proposed design of a capillary connecting element in an elastic medium of a strong dielectric.

Significantly reduced dimensions of the contact node ensured low specific capacitive and inductive characteristics that are not achieved by any known design of contact nodes, which is especially important when using contact nodes in structures operating in the GHz frequency range.

Claims (35)

CLAIM 1. The contact node at the oncoming contacts, containing at least two flat contacts and connecting these contacts to each other electrically and mechanically by a connecting element, each of these contacts being placed on the flat surface of one of the two coplanar carriers, the contacts being oriented towards each other and aligned with each other relative to a common axis orthogonal to the coplanar carriers and passing through the contact centers, and the gap between the coplanar carriers of the oncoming contacts and around the joint the body element is filled with a dielectric material, characterized in that the connecting element is made in the form of a metallized hole in a plane-parallel plate of dielectric material, which once - 22 010269 is placed in the gap between the coplanar carriers of the oncoming contacts, wherein said hole is a capillary with end flanges filled, partially or completely, with an electrically conductive binder material drawn into the said capillary from the oncoming contacts on which this material was previously placed, under the action of capillary forces arising during the transition of a binder of an electrically conductive material to a liquid state during technological action during the assembly of the contact node, with the formation after the termination of the technological impact of a mechanically stable electrically conductive connection between the opposing contacts, the longitudinal axis of the capillary passing through the centers of the said opposing contacts orthogonally to the surfaces of the said opposing contact carriers, and the said end flanges of the capillary located on the surfaces of the said plane-parallel carrier of the capillary connecting element are aligned end-to-end with the opposing contacts and are connected mechanically and electrically with them in a thin layer wrinkled binder conductive material. 2. The contact node according to claim 1, characterized in that said electrically conductive binder material is made of solder, and said technological impact is thermal. 3. The contact node according to claim 1, characterized in that said electrically conductive binder material is gel-like and wetting the inner surface of the capillary, its mentioned flanges and said counter contacts both during and after the termination of technological and other influences. 4. Contact node according to claims 2 and 3, characterized in that said electrically conductive binder material is preliminarily placed before the assembly of said contact nodes inside a capillary hole. 5. The contact node according to claim 1, characterized in that said counter contacts are offset relative to each other in the planes of their carriers, and the longitudinal axis of the capillary connecting element passing through the centers of the contacts is inclined at an angle α <90 ° to the surfaces carrying these contacts . 6. The contact node according to claim 1, characterized in that the capillary connecting element is made of a cylindrical shape. 7. The contact node according to claim 1, characterized in that the capillary connecting element is made in the form of a truncated cone, and the smaller bell of the capillary is connected to one oncoming contact, and the larger bell of the capillary is connected to another oncoming contact. 8. The contact node according to claim 7, characterized in that the said counter contacts are offset relative to each other in the planes of their carriers, and the longitudinal axis of the capillary connecting element made in the form of a truncated cone passing through the centers of the contacts is inclined to the planes carrying these contacts at an angle β <90 °. 9. The contact node according to claim 1, characterized in that the capillary connecting element is multi-channel. 10. The contact node according to claim 1, characterized in that the capillary connecting element is a porous structure that is permeable to an electrically conductive binder material during the technological action during the assembly of the contact node. 11. The contact node according to claim 1, characterized in that the inner surface of the capillary connecting element is made in the form of a surface of revolution relative to the longitudinal axis of the capillary. 12. The contact node according to claim 1, characterized in that the inner surface of the capillary connecting element is made in such a way that sections orthogonal to the longitudinal axis of the capillary are polygons. 13. The contact node according to claim 1, characterized in that the inner surface of the capillary connecting element is made in such a way that sections orthogonal to the longitudinal axis of the capillary are smooth closed curves. 14. The contact node according to claim 1, characterized in that the inner surface of the capillary connecting element is made in such a way that sections orthogonal to the longitudinal axis of the capillary are ellipses. 15. The contact node according to claim 1, characterized in that on the surfaces of the oncoming contacts technological protrusions are made with a bonding electrically conductive material deposited on them, while the said technological protrusions of the contact node enter the capillary, partially or completely, from its two sides, ensuring mutual self-alignment of said counter contacts and capillary connecting element during the assembly of the contact node. 16. The contact node according to clause 15, characterized in that the technological protrusion on at least one of the oncoming contacts of the said contact node is made in the form of a spherical protrusion of a binder of electrically conductive material, partially or completely placed in the capillary during alignment during assembly of the contact node . 17. The contact node according to clause 15, characterized in that both of the said counter contacts have - 23 010269 technological ledges identical in size and shape. 18. The contact node according to clause 15, characterized in that both of the said counter contacts have technological protrusions of different sizes and shapes, and the sockets of the capillary connecting element associated with them are made of various sizes and shapes and are complementary to the corresponding technological protrusions at the counter contacts. 19. The contact node according to claim 1, characterized in that the said plane-parallel carrier of the capillary connecting element is made in the form of a film of elastic material. 20. The contact node according to claim 19, characterized in that the said film is made of polyimide. 21. The contact node according to claim 1, characterized in that around the capillary connecting element made in the aforementioned plane-parallel carrier of dielectric material, this carrier has holes filled with an adhesive composition that glues the coplanar contact carriers in places free of contacts. 22. The contact node according to claim 1, characterized in that the said plane-parallel carrier of dielectric material, in which capillary connecting elements are formed, is made in the form of a rigid plate having thermomechanical characteristics identical to the thermomechanical characteristics of oncoming contact carriers. 23. The contact node according to item 22, wherein the carrier of the capillary connecting elements is made of either glass or oxidized silicon. 24. The contact node according to claim 1, characterized in that the carriers of capillary connecting elements and oncoming contacts are made of the same material. 25. The contact node according to paragraph 24, wherein both of the said bearing surfaces with counter contacts are made of either silicon or gallium arsenide or other semiconductor material, which, in addition to counter contacts, additionally have active and / or passive surfaces on their surfaces components and conductive tracks made according to planar technologies of microelectronics. 26. The contact node according to claim 1, characterized in that on the surfaces of the plane-parallel carrier of the capillary connecting elements are conductive tracks connecting at least two capillary connecting elements. 27. The contact node according to p. 26, characterized in that on the surfaces of the aforementioned plane-parallel carrier of the capillary connecting element is placed power bus and ground bus. 28. The contact node according to claim 1, characterized in that the carrier of capillary connecting elements is made in the form of a plane-parallel plate of electrically conductive material coated with a thin layer of insulating material, including the inner surfaces of the holes, and the capillary connecting elements, as well as active and / or passive components and conductive tracks made over said thin layer of insulating material. 29. The contact node according to p. 28, characterized in that the conductive base of the carrier of capillary connecting elements is made of either copper or aluminum. 30. The contact node according to clause 29, wherein the conductive carrier base of the capillary connecting elements, made of either copper or aluminum, is used as a ground bus. 31. The contact node according to claim 1, characterized in that the said carriers of the oncoming contacts, as well as the carrier of the capillary connecting elements located between the said carriers of the oncoming contacts, are made of various materials having the same thermomechanical characteristics. 32. A method of manufacturing a contact node in oncoming contacts with a capillary connecting element made in accordance with claim 1, comprising applying thin film layers of metallization and solder to one of the flat contacts; the manufacture of a blank of the connecting element for the said oncoming contacts and its tinning with solder; tinning with said solder of a reciprocal flat contact; the combination of oncoming flat contacts with the workpiece of the connecting element relative to the common axis passing through the centers of the said oncoming contacts, until they contact, with fixing the alignment for the time of soldering; heating the contact area of said counter contacts and the workpiece of the connecting element until the applied solder melts; lowering the temperature in the soldering zone until the curing of said solder between the said counter contacts with the formation of the connecting element of the contact node on the counter contacts; characterized in that the blank of the connecting element for oncoming contacts is made in the form of a metallized capillary hole in the dielectric film, the outputs of which are limited by end flanges on the surfaces of the said dielectric film, and the capillary hole is tinned with the mentioned solder at the same time as the end flanges, while the longitudinal axis the capillary hole coincides with the said axis of the corresponding flat counter contacts; said dielectric film being a carrier of said tinned capillary hole, during assembly of the contact assembly, is placed between said counter contact carriers so that the longitudinal axis of said capillary hole passes through the centers of said counter contacts orthogonally to the surfaces of said counter contact carriers and tinned capillary hole; after which the contact contact carriers are brought together on both sides of said carrier of a tinned capillary hole along said axis until the contact contacts come into contact with said end flanges of a tinned capillary hole; the area between the said oncoming contact carriers is evacuated to 0.1 atm, while fixing the relative position of the oncoming contact carriers and the carrier of the tinned capillary hole located between them; adjusting the temperature in said region to the melting point of the solder, allowing the molten solder to rise into the tinned capillary hole from the oncoming contacts tinned with said solder; during cooling and curing of the solder in the capillary hole, as well as in the gaps between the end flanges of the capillary hole and the corresponding counter contacts, a capillary connecting element is formed between the said counter contacts, providing a rigid fixation of the solder in the metallized capillary hole of the said capillary connecting element of the contact node, during subsequent technological impacts and during its operation as part of microelectronic equipment; wherein the rise height of the solder in the capillary connecting element during the formation of the capillary connecting element is determined by the formula 2 · χ „· · οο8 ^ · (1 + 3α · (Τ _η -Τ ₀ )) 'G'GA where ρ ₀ = 8540 kg / m ³ ; α = 21-10 ^{6 about} C ^-1 ; S is the height of the rise of the molten solder in the capillary connecting element; γ is the surface tension coefficient of solder; θ is the wettability angle of the solder; α is the coefficient of linear expansion of the solder; ρ0 is the solder density under normal conditions; T _about - solder temperature in degrees Kelvin under normal conditions; T _p - the temperature of the molten solder in degrees Kelvin. 33. The method according to p. 32, characterized in that on the said flat contact located on one of the bearing surfaces, and / or on the counter oncoming flat contact located on the other bearing surface, tinned protrusions are formed, partially or completely entering the hole of said capillary connecting element, which are used as elements of mutual-based mentioned counter contacts and capillary connecting element. 34. The method according to p. 33, characterized in that the protrusions on the oncoming contacts, partially or fully included in the holes of the capillary connecting element, are made in the form of identically formed doses of solder. 35. The method according to p, characterized in that one of the aforementioned bearing surfaces with contacts is the surface of the IC chip with contacts, and the other said surface bearing the response contacts is a surface with response contacts of the switching substrate.