FR2853202A1 - METHOD FOR PRODUCING HIGHLY HERMETIC ELECTRONIC OR OPTOELECTRONIC PACKAGES INCLUDING AT LEAST ONE THERMOELECTRIC EFFECT REGULATION AND DISSIPATION SYSTEM - Google Patents

Abstract

Process for producing thermo-regulating electronic or optoelectronic boxes, highly hermetic, of ceramic / ceramic or ceramic / metal type, with a ceramic bottom in the form of a flat plate or cell, integrating at least one regulation and heat dissipation system by thermoelectric effect (Peltier), of which at least one of the external and internal faces participates in the creation of said externalized and / or internalized Peltier.

Description

Method for producing electronic boxes or

  Field of the Invention The invention relates to a method for producing electronic or optoelectronic packages, of good mechanical strength, thermoregulating, ensuring the obtaining highly hermetic housings to resist attacks developed in their operating environment, in particular aggressive agents, liquid or gaseous, significant variations in temperature and pressure, capable of withstanding a high vacuum without leaks, and incorporating at least one regulation and heat dissipation by thermoelectric effect (Peltier).

  The invention relates more particularly to a process for producing electronic or optoelectronic boxes, thermoregulating, of good mechanical resistance, making them highly hermetic to the aggressions of their operating environment, of ceramic / ceramic or ceramic / metal type, the ceramic base, can have the shape of a flat or cellular plate, and at least one of the internal and external faces of which contributes in whole or in part to at least one integrated system of regulation and of heat dissipation by a thermoelectric effect ( Peltier), said ceramic base 30 forming one of the constituent plates of said Peltier.

  The invention also relates to highly hermetic thermoregulating electronic or optoelectronic boxes, of good mechanical resistance, of ceramic / ceramic or ceramic / metal type, with ceramic bottom, participating in whole or in part in at least one regulation and dissipation system. thermal by thermoelectric effect (Peltier), obtained according to the method and intended to receive various electrical and / or electronic and / or optoelectronic components, with a view to collecting and protecting them.

  The invention finally relates to the application of electronic or optoelectronic, thermoregulating, highly hermetic packages obtained by the process, in fields such as, for example, aerospace, transport technologies, telephony, electronics or other.

  STATE OF THE ART Electronic or optoelectronic boxes are generally formed of a ceramic bottom integrating three-dimensional electrical circuits, on which is brazed a frame or a cover, 20 boxes whose desired characteristics are to have low coefficients of thermal expansion and desirably to be and remain hermetic to gases, including water vapor, despite the thermal cycles or pressure and vacuum cycles to which these housings can be subjected in their installation and operating environment.

  The components integrated in these types of housings increasingly relate to electronic or optoelectronic systems which require operating under controlled and regulated temperatures, in order to reduce, as far as possible, the operational hazards which result from temperature differences generated internally during their operation, the electronic or optoelectronic components present in said boxes, generating calories which must be eliminated.

  The state of the art already teaches that the addition, inside such cases, of regulation and heat dissipation systems by thermoelectric effect (Peltier), 5 makes it possible to reduce the thermal load applied to the various electronic or optoelectronic components present. inside the housing.

  The thermoelectric (Peltier) regulation and heat dissipation systems consist of two ceramic plates, one of the plates being the hot plate and the other the cold plate, these two ceramic plates being provided with conductive tracks and connected together by semiconductors in contact with the conductive tracks, and being supplied with electric current. This supply of electric current, through the semiconductor circuit, generates a thermal effect conveying the calories from the cold plate to the hot plate. The hot plate is itself fixed to the bottom of the housing, and plays the role of sensor and heat sink 20, said bottom of the housing itself being connected to, for example, a metal support part, external to the housing.

  Due to the need to place an increasing number of components in a limited space, because the 25 cases are more and more miniaturized, but also because the cases are more and more flat, the state of the technique reveals and describes different solutions for the production of infinitely more heat dissipating packages and, therefore, incorporating a regulation and heat dissipation system 30 by thermoelectric effect (Peltier).

  A first document (patent application US 2002/0003819 Ai) describes the positioning of the Peltier in an open window in the bottom of the housing, the bottom plate, ie the hot plate, of the Peltier coming to fit in this window from the bottom of the case to reduce the total thickness.

  The installation of a Peltier in this opening constitutes a novelty compared to the state of the art which previously recommends only fixing the lower plate of the Peltier on the bottom of the case containing it like any other. electronic component, such as an integrated circuit.

  Despite its advantage, this solution has drawbacks 10 some of which are major. One of them is the need to have great precision in the dimensional tolerances, between the thickness of the bottom plate of the Peltier, that is to say the hot plate and the bottom of the case, which therefore has this window provided with an internal frame ensuring the positioning of the 15 Peltier both in height and in the horizontal plane. This geometrical obligation means that any level difference between the bottom of the case and the lower Peltier plate can cause ruptures of the ceramic bottom, by fragile nature, as soon as the case is fixed on an external support, but also restrict heat flows if the bottom of the Peltier is not really in contact with the dissipating external support on which it is fixed. Furthermore, as a particularly optoelectronic package must have a high hermeticity, the existence of an additional opening 25 in its bottom increases the risks of loss of hermeticity.

  Another document (patent application US 2002/0085598 A1) describes the positioning of a Peltier on the bottom of an optoelectronic box, the lower plate of which, said hot plate 30 is fixed on said bottom. To gain space in the height of the enclosure, the upper Peltier plate, i.e. the cold plate, is used as a support plate for the electronic or optoelectronic components contained in the housing, whereas in the state of the art, it is known that an intermediate plate is generally added in contact with the upper face of the Peltier, to receive the optoelectronic elements disposed within the housing. In this solution it may appear that the 5 heat exchanges between the bottom of the Peltier and the bottom of the case are a function of the excellence of the interface between these two bottoms both in terms of geometry of the bottoms and in terms of their conductivity thermal.

  Another document (Japanese patent application N0JP5067844) proposes an important advance with regard to the state of the art, which consists in using the ceramic bottom plate of the housing as a bottom plate or hot plate, of Peltier, this plate lower of the Peltier being placed on the 15 sides of the frame or the housing cover.

  However, if the latter solution is indeed a source of space savings in height, and potentially a source of economic savings, by the common use of a single ceramic plate for two functions, that is to say the ceramic plate lower of the Peltier becoming the ceramic bottom plate of the case, it seems that it cannot meet, in its architecture of a box with a frame or cover assembled with the ceramic bottom plate, the requirements of high hermeticity and great mechanical resistance for The box.

  Thus, the state of the art, and in particular the aforementioned documents examined, does not precisely describe the means to be used during the mounting of the electronic or optoelectronic boxes, so that these boxes have a hermetic seal sufficient to face difficult operating conditions.

  Because, all these electronic or optoelectronic boxes have an increasingly refined and complex architecture which result from the obligations to be less bulky, lighter, and to contain more and more electronic or optoelectronic components. These obligations are imposed on the boxes for economic reasons and operational constraints.

  However, real consequences are manifested in the electronic and optoelectronic packages placed on the market, these consequences being possibly operational defects of the contained electronic or optoelectronic components and / or loss of hermeticity and / or mechanical fragility when the conditions operating conditions include variations in temperature and / or pressure, vacuum conditions, vibration actions when the housings are operated, for example, in motor vehicles, collective means of transport, such as boats, trains, planes, or rockets, satellites or whatever.

  However, there is an increasingly demanding demand on the market for electronic or optoelectronic packages with very high hermeticity and excellent mechanical resistance, and this, in particular, for thermoregulating packages with regulation and heat dissipation system. by thermoelectric effect (Peltier) whose ceramic bottom is formed by the hot bottom plate of the Peltier. This high vacuum tightness is to be ensured whatever the thermal, pressure and vibration cycles to which the housing is subjected, since some of the electronic or optoelectronic components must operate under conditions of high vacuum and / or in atmospheres controlled.

  Objectives of the invention Consequently, the invention pursues a certain number of objectives, in order to meet the needs for use of such thermo5 regulating boxes, even under extreme conditions, so that it can best eliminate the aforementioned drawbacks and that it provides adapted and improved solutions compared to the various means used in thermoregulating electronic or optoelectronic boxes.

  Throughout the description of the subject of the invention, the high hermeticity of the housing will be expressed by a helium leakage rate of less than 10-8 cm3 per second under 1 atmosphere of differential pressure at room temperature of 230C 15 when measured according to the standards American Military Standards MIL-STD-883, method 1014 Condition A. A first object of the invention is to create a process for producing thermo-regulating electronic or optoelectronic boxes, of high hermeticity and of good mechanical resistance, of the ceramic / ceramic or ceramic / metal type, with a ceramic base, containing at least one regulation and heat dissipation system by thermoelectric effect (Peltier).

  Another object of the invention is to create a process for producing thermo-regulating electronic or optoelectronic boxes of high hermeticity, of good mechanical resistance, of the ceramic / ceramic or ceramic / metal type, with a ceramic base which consists in using as the housing bottom, either of the lower or upper plates of the Peltier. A simplified way to visualize this type of case is to consider that the ceramic base, called to receive other electrical, electronic and optoelectronic components, is assembled with a "half-Peltier", this half-Peltier being formed from the other ceramic plate Peltier and semiconductor, assembled with this other plate. Such an assembly with the ceramic base of the housing creates, for example, at least one Peltier internal or external to the housing, when the "demiPeltier" is associated with the internal face or the external face of the ceramic base of the housing, or two internal Peltiers - external to the case when two "half-Peltier" are associated with the internal and external faces of the ceramic bottom of the case.

  Another object of the invention is to create a process for producing thermo-regulating electronic or optoelectronic packages of high hermeticity, of good mechanical resistance and with high heat dissipation capacity, of the ceramic / ceramic or ceramic / metal type, including at least one of the external and internal faces of the ceramic base is used like one or the other of the lower or upper plates of at least one Peltier and the surface of which is occupied in whole or in part by at least one Peltier.

  Another object of the invention is to create a process for producing thermoregulating electronic or optoelectronic boxes, of good mechanical strength, of the ceramic / ceramic or ceramic / metal type, having a ceramic bottom, of high hermeticity, it is that is to say having a helium leakage rate which must be less than 10-8 cm3 per second under an atmosphere of differential pressure, at ambient temperature of 230C, when measured according to the American Military Standards standard MIL-STD-883 , method 1014 Condition A. 30

Summary of the invention

  All the objectives set out above can be achieved thanks to the electronic or optoelectronic box, object of the invention.

  According to the invention, the process for producing highly hermetic thermoregulating electronic or optoelectronic boxes, of good mechanical strength and with high heat dissipation capacity, of the ceramic / ceramic or ceramic / metal type, with a ceramic base, integrating into the minus a thermoelectric regulation and heat dissipation system (Peltier) which each consist of: * a ceramic base constituting one of the plates of the thermoelectric system (Peltier), * a ceramic frame or cover or metallic, associated with the ceramic bottom, * connection pins mounted in the case via ceramic inserts in the case where the frame is metallic, or integrated in the ceramic of the bottom or of the frame wall when the frame is made of ceramic, 25 * of means for fixing the housing to a support, * possibly of at least one orifice in the case of optoelectronic housings, * d another ceramic plate associated with semiconductors, this assembly forming the part of the thermoelectric system (Peltier) associated with the ceramic base, - 10 is characterized in that said method comprises the steps a) of creation of sheets of raw ceramic by pouring a mineral suspension comprising powdery ceramic materials dispersed in a liquid organic phase formed of a liquid organic matrix and of at least one organic solvent and drying the sheets formed to remove the at least one organic solvent, b) creation on the plane (X, Y) of dried raw ceramic sheets, of metal tracks, to form all the conducting circuits, the sealing or soldering tracks and the soldering tracks, by means of a suspension of metallic particles, or ink, formed by dispersing at least one powdery refractory metal, in a liquid organic phase formed of a liquid organic matrix and at least one solvent, then drying of the tracks to remove the at least one solvent, c) creation of internal vertical channels or vias in the third dimension (Z), by drilling the dried raw ceramic sheets and filling the channels with a ink or metallization paste formed by means of a suspension of metallic particles dispersed in a liquid organic phase consisting of a liquid organic matrix and at least one solvent, d) creation of a homogeneous block to form the base in raw ceramic by stacking the various sheets of raw ceramic shaped, cut, provided with their metal tracks and vertical tracks filled with ink, then by compression of the stack and by sintering of the homogeneous ceramic block compressed at a temperature d '' at least 1350OC. - he

  e) assembly by soldering on the sintered ceramic bottom of the ceramic or metallic frame and interconnection pins at a temperature between 2750C and 8000C., f) assembly by welding of the semiconductors of at least one system regulation and heat dissipation by thermoelectric effect (Peltier) on at least one of the external and internal faces of the ceramic background, in line with the tracks 10 initially created, at a temperature between 130 ° C. and 2400 C. 'Therefore, the invention relates to a process for producing thermo-regulating electronic or optoelectronic boxes 15 which are highly hermetic and of good mechanical strength, of the ceramic / ceramic or ceramic / metal type, with a ceramic base of which at least one of the external or internal faces is provided with at least one regulation and heat dissipation system by thermoelectric effect (Peltier), structured in such a way that at least one of the external or internal faces of the ceramic bottom of the housing, or simultaneously the external and internal faces of said bottom constituting one of the ceramic plates on which the semiconductor components are soldered in the form of interconnected pads, between said bottom of the housing and the other plate of the regulation and heat dissipation system by thermoelectric effect (Peltier).

  The invention also relates to a method for producing thermoregulating packages (Peltier) which have a high hermeticity expressed by a helium leakage rate of less than 10-8 cm3 per second under an atmosphere of differential pressure at room temperature. 230C when measured according to the American military standards MIL-STD-883, method 1014 Condition A. - 12 The invention finally relates to the creation, by the production process, of thermo-regulating electronic or optoelectronic boxes of high hermeticity, of good mechanical strength, of the ceramic / ceramic or ceramic / metal type, 5 provided with a ceramic base, at least one of the external or internal faces of said base constitutes one of the ceramic plates of at least one Peltier and of which the surface of said face is occupied in whole or in part by at least one Peltier external or internal to the housing.

  Detailed description of the invention

  According to the invention, it is possible to create, by the production method, an electronic or optoelectronic thermoregulating housing, of high hermeticity, of good mechanical resistance, of the ceramic / ceramic or ceramic / metal type, with ceramic base, of which the at least one of the external and internal faces of said ceramic base constitutes (s) one of the ceramic plates 20 of at least one external Peltier and / or at least one internal Peltier, said external and internal surfaces being occupied in all or part by at least one Peltier.

  According to the invention, it is also possible to create an electronic or optoelectronic thermo-regulating housing 25, of high hermeticity, of the ceramic / ceramic or ceramic / metal type, the ceramic bottom of which may have the form: * of a ceramic cell simple having in section the shape of the letter U, the edges of which are oriented towards the inside or the outside of the case, depending on whether the Peltier is placed internally or outside the case, or - 13 * of a cell double ceramic having in section the shape of the letter H, occupied in whole or in part by at least one Peltier in each cell, the edges of which are oriented towards the inside and outside of the case when two Peltier are placed, the one inside the case and the other outside the case, or * a flat ceramic plate, at least one of the external or internal faces of said ceramic base, or simultaneously the 10 external faces 'and internal of said fund cons titue (s) one of the ceramic plates on which the semiconductor components appear in the form of interconnected pads, taken between said bottom of the housing and the other plate of the regulation and heat dissipation system by thermoelectric effect (Peltier).

  Consequently, according to the invention, each of the external and internal faces previously mentioned of the ceramic background, can participate in the creation of at least one Peltier, that is to say that each face can be the base of two Peltiers and more, placed next to each other and / or superimposed if necessary to effectively organize regulation and heat dissipation by thermoelectric effect, depending on the size of the housing.

  The production of electronic or optoelectronic boxes of the ceramic / ceramic or ceramic / metal type is based on known techniques.

  In the context of the invention, one of the essential elements of such electronic or optoelectronic packages is constituted by the ceramic bottom plate integrating three-dimensional electrical circuits, which is generally produced by a stack of ceramic sheets subsequently subjected to a sintering operation. - 14

  The process for producing the bottom ceramic plate operates in several distinct stages, which are the preparation of ceramic materials, the formation of ceramic sheets, the processing of these sheets, the assembly of the raw ceramic sheets, the sintering of the sheets in raw ceramic assembled and post-sintering treatments.

  The multilayer technique for producing the bottom plate of the ceramic case, as well as of the frame in the case of ceramic / ceramic cases, uses raw ceramic sheets to create different insulating layers, which will then be stacked. A network of interconnections is created by screen printing of metallic inks on the green ceramic sheets 15 along a two-dimensional plane (axes X, Y), while the vertical connections in the third dimension (axis Z) are obtained by drilling holes and filling them with a conductive metallic ink. These creations of flat tracks and metallized vertical tracks, for high temperature firing ceramics, are made by means of metallic compositions based on tungsten and / or Molybdenum.

  The powdery ceramic materials used in the preparation of a ceramic suspension in the liquid phase (slip), involved in the process according to the invention for the creation of raw ceramic sheets, are essentially chosen from the group consisting of aluminas and / or aluminum nitrides, optionally combined with other powdery components such as, for example, talc, kaolin, wollastonite, pigments such as chromium oxide.

  The suspension of ceramic powder materials in the organic liquid phase formed of at least one organic binder, at least one organic solvent, a dispersant and - optionally a plasticizing agent and / or a lubricating agent, consists of: * 50 to 75% by weight of the mixture of ceramic materials 5 essentially consisting of A1203 and / or aluminum nitride, so that after a high temperature heat treatment, such as sintering, the content alumina and / or aluminum nitride of the product from sintering contains of the order of at least about 92% by weight of alumina and / or aluminum niture following the removal of said liquid phase, * from 5 to 15% by weight of at least one organic binder, * from 15 to 45% by weight of at least one organic solvent, * from 0 to 5% by weight of at least one plasticizing agent and / or a lubricating agent.

  The diametral dimension of the grains constituting the constituent ceramic materials is well known to those skilled in the art.

  However, this preferred diametrical dimension appears to be between 0.5 and 5 μm.

  The organic binder used in the context of the invention for the preparation of the suspension of ceramic materials in an organic liquid phase is chosen so that it conditions the obtaining, from said suspension, of a ceramic sheet. raw non-brittle and free from excessive stiffness. In addition, this organic binder is chosen in such a way that during the sintering operation, it does not leave or leaves a minute amount of carbon in the sintered ceramic.

  This organic binder can be chosen from the polymers known from the state of the art and in particular from the group of polymers including polyvinyl butyral, acrylic or methacrylic polymers, acrylates or methacrylates, polyvinyl alcohols, polyolefins.

  A plasticizing agent aiding in the formation of a non-brittle raw ceramic sheet free of excessive rigidity may also accompany the organic binder. The plasticizing agent, which can enter into the formation of the suspension of pulverulent materials, can be chosen from group 10 consisting of polyalkylene glycols, such as for example polyethylene glycol, ethylene glycol, monoethyl ethers of ethylene glycol, alkyl phthalates, in particular dibutylphthalate used alone or as a mixture.

  The organic solvent used in the context of the invention for the preparation of the suspension of ceramic materials to form the organic liquid phase, can be chosen from the solvents known from the prior art and more particularly from the group of solvents formed by alcohols, such as methanol and ethanol, ketones such as methyl ethyl ketone, halogenated solvents such as trichloroethane, trichlorethylene, taken alone or as a mixture.

  All the percentages by weight of the components involved in the creation of the suspension of ceramic materials in an organic liquid phase are: * defined in order to be able to obtain raw ceramic sheets offering sufficient mechanical strength in the range of the desired thicknesses, * in relationships between mineral and organic components leading to control of the desired mechanical characteristics to control the evaporation kinetics of the various solvents when the ceramic suspension changes from its liquid state at the time of the formation of the sheet to a flexible solid state after said evaporation.

  For the creation of raw ceramic sheets, the suspension of ceramic materials in the liquid organic phase is poured onto a support, generally a thin sheet of synthetic material, then passed under a blade which will distribute the suspension on the support in order to produce a strip of raw ceramic of specific and uniform thickness. After its formation, the raw ceramic strip is subjected to the elimination of organic solvents by a drying action.

  Once dry, and once the support has been delaminated, this strip becomes a ceramic layer which is easy to handle in rolls or in sheets, facilitating the various phases of assembly and treatment carried out on their surfaces and / or through them.

  As soon as the ceramic strip is dry, circuits, some of which have a conductive function and the others a hooking function for soldering and / or sealing and / or soldering of the various elements between them from the housing to assembly, are printed on the ceramic sheets in appropriate patterns, using metallic inks with liquid organic phase containing at least one organic solvent. At the end of the circuit printing, the raw ceramic sheets are subjected to the elimination of organic solvents by a drying action.

  According to the invention, the creation of metallized tracks on the raw ceramic sheet, whether it is made of alumina or aluminum nitride, intended by assembly to simultaneously become the bottom of the housing and one of the Peltier plates is made by l either of the printing or coating techniques, in particular screen printing, by means of inks comprising in their formulation refractory metallic materials, such as tungsten, molybdenum used alone or in mixtures.

  Other tracks, such as those, for example, concerning the interconnection pins, and those intended to receive the "Peltier" semiconductors, are made by the same printing means using the same metallic inks.

  These various types of tracks must, in fact, allow soldering and / or seals which are sufficiently resistant and reliable, which withstand the thermal cycles and the pressure variation cycles which result from the operating conditions of the housings. Any thermal variations or variations in the pressures to which the housings can be subjected generate concentrated mechanical stresses at the interfaces, subjecting these interfaces to fatigue phenomena generating risks of loss of tightness at this level. In the case of interconnection pins, the bending stresses during assemblies and bends of said pins require high resistance to hooking.

  Likewise, the raw ceramic sheets are provided with vertically shaped holes which, as soon as they are filled with a conductive metallic paste, with liquid organic phase containing at least one organic solvent, form channels or "vias" conductive enabling, through the various layers of ceramic sheets, to assume the connection between the conductive metal tracks of the various ceramic layers and all the functions of the communication and interconnection circuits between the internal components and the external environment of the housing. - 19

  Metallic inks, for the printing of conductive tracks or intended to create sealing and soldering tracks and metallic pastes for filling vertical or vias tracks between ceramic layers, are suspensions of powdery refractory metals, in an organic liquid phase of viscosity adapted to each use.

  The powdery refractory metals are preferably chosen from the group consisting of tungsten and molybdenum, used alone or in combination. These metals can easily withstand the temperatures used for sintering raw ceramic sheets, the minimum temperature of which is at least 1350 ° C.

  The particle size of the pulverulent tungsten and molybdenum is desirably between 0.5 and 2.5 μm and preferably between 0.5 and 1.5 μm.

  The liquid organic phase is formed using the same organic binders and the same organic solvents as those used in the preparation of the ceramic suspension, it being understood that the amounts of the various components in% by weight are determined according to the use which will be made of said refractory metal suspension.

  As soon as the different raw ceramic sheets have received the respective screen printing patterns, by means of the aforementioned refractory ink, the different sheets shaped and cut to size, are stacked to form, by compression, a homogeneous block of raw ceramic sheets, in the form of a single or double plate or cell in raw ceramic, the elimination of most of the organic matter (binders and solvents) taking place at low temperature, in a drying action, according to slow kinetics, prior to the sintering operation.

  The vias which have previously been filled with conductive paste consisting of a suspension of refractory pulverulent metals dispersed in a liquid organic phase, become, once the sintering has been carried out, the vertical electrical interconnections between the horizontal conductive circuits printed 10 or screen printed on the different layers of raw ceramic, assembled one on top of the other.

  The raw ceramic bottom plate or cell, according to the invention resulting from the compression of the stack of the 15 raw sheets prepared as above, then undergoes a sintering operation at a temperature of at least 13,500 ° C. and preferably at a temperature between 14500 C and 18000 C. This sintering operation can be carried out under a controlled, generally reducing, atmosphere and can be carried out under a load such that the withdrawal which is generally carried out in three dimensions ( X, Y, Z), can only be done in the vertical axis (Z). 25 The soldering of the metallic or ceramic frame constituting the vertical walls of the housing, on the track of the ceramic bottom plate, takes place between 275 ° C. and 800 ° C., to give a high hermeticity to the housing. This assembly is done at temperatures of at least 275 ° C., that is to say uses gold / tin type solders, or preferably at temperatures of at least 350 ° C., that is to say uses gold solders / germanium, or even more preferably at temperatures of at least 7800C, that is to say uses solder - 21 silver / copper. Such solders are chosen to provide the enclosure and the electronic or optoelectronic components contained with a hermetic seal of the enclosure and therefore excellent protection of the components because said solders 5 are sufficiently ductile to withstand thermal cycles, pressure variation, and the mechanical stresses to which the housings are subjected without the risk of creating cracks or cracks in the assemblies, generating unacceptable leaks when the vacuum is created inside the housing, or allowing penetrations from the outside to inside the housing.

  The interconnection pins, whether or not fitted with ceramic inserts, depending on whether or not these pins must pass through the metal frame, are soldered under identical conditions, in order to allow this operation to be carried out at the same time as the soldering metal frame on the bottom of the case.

  In the case of optoelectronic packages, the lens holding systems can use crimps or solderings.

  The systems for fixing the housing to the support intended to receive it include various metal parts, with a low coefficient of thermal expansion, such as fixing lugs, ears, jumpers, nuts, screws, metal straps, flanges, which are fixed by soldering on the ceramic bottom of the housing having previously received an appropriate metal track. Such assemblies use the same brazing means as those previously mentioned. However, for applications in the automotive field, new mechanical constraints, in particular of resistance to vibration over long service periods, impose high mechanical resistances at these interfaces. - 22

  The assembly of the semiconductors of the regulation and heat dissipation system by thermoelectric effect (Peltier) on the external face at least of the bottom of the case in line with the tracks 5 initially created, is done by welding between 130 OC and 240 OC.

  The solders use tin-based compositions, in order to remain at temperatures low enough not to risk damaging the semiconductor components of the Peltier.

  These solders are of the bismuth tin type, with a melting point of 10 1400C, or of the lead tin type, with a melting point of 232 0C, or of the tin tin type, with a melting point of 232 0C.

  The choice of solder compositions is made in such a way that there is * no metallic diffusion in the semiconductors when soldering takes place, * no metallic soiling and / or deposition of an organic phase. volatile on the lens of the optoelectronic system when this lens is already present in the previously brazed frame.

  Helium leakage measurements making it possible to check the hermeticity of the housing are made once the metal cover of the housing is welded to the metal frame, in the case of a metal frame housing or once the cover is brazed to the ceramic plate constituting the bottom of the case.

  The detection of the loss of hermeticity for such boxes called to receive electronic or optoelectronic components is critical because the entry of contaminants inside the protective box risks being highly detrimental to the functioning of the incorporated components and - 23 reduces the effective life of said components. Water vapor, for example, present in or entering the housing acts as a contaminant and is a major drawback for the components.

  The invention also relates to thermo-regulating electronic and / or optoelectronic thermo-regulating, hermetic boxes, of good mechanical strength, ceramic / ceramic or ceramic / metal, with ceramic base, incorporating at least one regulation and heat dissipation system. by thermoelectric effect (Peltier), obtained according to the method and intended to receive different electrical and electronic components as well as optoelectronics in order to collect and protect them. The ceramic bottom of these boxes has the form * of a simple ceramic cell having in section the shape of the letter U, the edges of which are oriented towards the inside or outside of the box, depending on whether the Peltier is placed internally or externally to the housing, or * of a double ceramic cell having in section the shape of the letter H, occupied in whole or in part by at least one Peltier in each cell, the edges of which are oriented inwards and the outside of the case when two Peltiers are placed, one inside the case and the other outside the case, or even 30 * of a flat ceramic plate, at least one of the external or internal faces of said ceramic bottom, or simultaneously the external and internal faces of said bottom constitute (s) one of the ceramic plates on which - 24 the semiconductor components appear in the form of interconnected pads, sandwiched between said bottom of the housing and the other plate of the thermoelectric effect regulation and dissipation system (Peltier).

  Such highly hermetic ceramic / ceramic or ceramic / metal type thermo-regulating boxes, with a ceramic bottom, according to the invention, incorporating a thermoelectric effect (Peltier) regulation and heat dissipation system are used in all systems. using sensitive electronic or optoelectronic components, which must first be protected and then thermoregulated. These boxes are present in numerous industrial applications, in on-board systems as well as satellites, missiles, airplanes, means of public transport, cars, in all telecommunications, data transmission systems, such as relays, terminals, exchanges.

  They can also be present on goods such as industrial equipment and durable consumer goods, incorporating sensor elements and signal conversion and processing.

  The invention will be better understood from the numerical description of the figures mentioned below, these figures having only a nonlimiting illustrative nature.

  Figure 1 is a vertical section of an electronic or optoelectronic box whose ceramic bottom is formed by a cell containing an internal "Peltier". - 25

  Figure 2 is a vertical section of an electronic or optoelectronic box whose ceramic bottom is formed of a cell containing an external Peltier.

  Figure 3 is a vertical section of an electronic or optoelectronic box whose ceramic bottom is formed of two cells containing an internal Peltier and an external Peltier.

  Figure 4 is an open perspective view on the front 10 of an electronic or optoelectronic box whose ceramic bottom is formed of a cell containing an internal Peltier.

  Figure 5 is an enlarged detail in perspective from Figure 4.

  Figure 6 is a vertical section of an electronic or optoelectronic box whose ceramic bottom is formed of a ceramic plate participating in an external Peltier.

  Figure 7 is a vertical section of an electronic or optoelectronic box whose ceramic bottom is formed of a ceramic plate participating simultaneously in an internal Peltier and an external Peltier.

  Figure 8 is a vertical section of an electronic or optoelectronic box whose ceramic bottom is formed by a plate participating in a superimposed double external Peltier.

  According to FIG. 1, the electronic or optoelectronic box 30 (1) comprises, as the bottom of the box, a ceramic cell (2) integrally comprising a bottom (3) and an edge (4) facing the inside of the box. The ceramic cell (2) constitutes one of the plates of a thermoelectric regulation and dissipation system comprising another ceramic plate (5) r 2 - 26 associated with semiconductors (6), this assembly which comprises the ceramic plate (2), the plate (5) and the semiconductors (6), forming the thermo-regulating system (Peltier).

  A metal frame (7) made of iron alloy with Nickel 29%, Cobalt 17% and Manganese 0.2% (Kovar) is brazed to the ceramic cell (2), the frame (7) and ceramic cell (2 ) forming an electronic or optoelectronic box capable of being closed by a cover plate and containing the thermoelectric regulation and dissipation system (Peltier).

  According to FIG. 2, the electronic or optoelectronic box (1) comprises, as the bottom of the box, a ceramic cell (8) integrally comprising the bottom (3) and the edge (9), turned towards the outside of the box (1 ). The ceramic cell (8) constitutes one of the plates of a thermoelectric regulation and dissipation system comprising another ceramic plate (10) associated with semiconductors, this assembly which comprises the ceramic cell (8), the plate (5) and the semiconductors, forming the thermo-regulating system (Peltier).

  An iron alloy metal frame (7) with Nickel 29%, Cobalt 17% and Manganese 0.2% (Kovar) is brazed to the ceramic cell (8), the frame (7) and ceramic cell (8 ) 25 forming an electronic or optoelectronic box capable of being closed by a cover plate whose thermoelectric regulation and dissipation system (Peltier) is external to said box.

  According to FIG. (3), the electronic or optoelectronic box (1) comprises, as the bottom of the box, two ceramic cells (2) and (8) back-to-back with one another by the common bottom (3) provided with an edge (4) facing the inside of the housing and an edge (9) facing the outside of the housing.

  7 - 27 The ceramic cells (2) and (8) each constitute one of the plates (3) of a first internal thermoelectric regulation and dissipation system comprising another ceramic plate (5) associated with semiconductors (6 ) and a second external thermoelectric regulation and dissipation system 5 comprising another ceramic plate (10) associated with semiconductors (11).

  A metal frame (7) made of iron alloy with Nickel 29%, Cobalt 10 17% and Manganese 0.2% (Kovar) is brazed on the edge (4) of the cell (2), the frame assembly (7 ) ceramic cells (2) and (8) forming the electronic or optoelectronic box, comprising two thermoregulating systems (Peltier), one internal and the other external to the box, said box being capable of being closed by a plate - hood (not shown).

  Figures (4) and (5) in accordance with Figure (1) reveal the bottom (3), the edge (4), the cell (2) containing the Peltier, the cell (3) of which is one of the plates, the other plate (5) and the semi-conductors (6) of the Peltier, the metallic frame of iron alloy with Nickel 29%, Cobalt 17% and Manganese 0.2% (Kovar) (7) and the pins 12 , 13 and 14.

  According to FIG. 6, the electronic or optoelectronic box (1) 25 comprises, as the bottom of the box, a ceramic plate (22). This ceramic base (22) constitutes, by its external face (23) one of the plates of an externalized thermoelectric regulation and dissipation system comprising another ceramic plate (25) associated with semiconductors (26), this assembly which comprises the ceramic plate (22), the plate (25) and the semiconductors (26), forming the thermoregulating system (Peltier) of the housing.

  An iron alloy metal frame (27) with Nickel 29%, Cobalt 17% and Manganese 0.2% (Kovar) is brazed to the ceramic plate (22), the frame (27) and ceramic plate (22) assembly forming an electronic or optoelectronic box capable of being closed by a cover plate and containing the externalized thermoelectric regulation and dissipation system (Peltier). According to FIG. 7, the electronic or optoelectronic box (1) has as its bottom housing, a ceramic plate (22).

  The ceramic plate (22) constitutes, by its external face (23), one of the ceramic plates of a first externalized thermoelectric regulation and dissipation system comprising another ceramic plate (25) associated with semiconductors (26 ), this first assembly forming said external thermo-regulating system (Peltier), and by its internal face (24), one of the ceramic plates of a second internal thermoelectric regulation and dissipation system, comprising another ceramic plate ( 28), associated with semiconductors (29), this second assembly forming said internal self-regulating system (Peltier).

  An iron alloy metal frame (27) with Nickel 29%, 20 Cobalt 17% and Manganese 0.2% (Kovar) is brazed to the ceramic plate (22), the frame (27) and ceramic plate (22 ) forming an electronic or optoelectronic box capable of being closed by a cover plate whose thermoelectric regulation and dissipation system (Peltier) is external and internal to said box.

  According to FIG. (8), the electronic or optoelectronic box (1) has a ceramic plate (22) as the bottom of the box.

  This ceramic bottom (22) by its external face (23) constitutes one of the plates of a first outsourced thermoelectric regulation and dissipation system comprising another ceramic plate (25) associated with semiconductors (26). This other plate (25) participates in the creation of a second external thermoelectric regulation and dissipation system comprising - 29 another ceramic plate (30) associated with semiconductors (31).

  An iron alloy metal frame (27) with Nickel 29%, 5 Cobalt 17% and Manganese 0.2% (Kovar) is brazed to the plate (22), the frame assembly (27), plate (22) in ceramic forming the electronic or optoelectronic box, comprising two external thermo-regulating systems (Peltier), one and the other being superimposed. -

Claims (20)

claims   1. Method for producing highly hermetic thermoregulating electronic or optoelectronic boxes, of good mechanical strength and with high heat dissipation capacity, of the ceramic / ceramic or ceramic / metal type, with a ceramic base, incorporating at least one regulation and heat dissipation by thermoelectric effect (Peltier) each comprising * a ceramic base constituting one of the plates of the thermoelectric system (Peltier), * a ceramic or metallic frame or cover, associated with the ceramic background, * connection pins mounted in the housing by means of ceramic inserts in the case where the frame is metallic, or integrated in the ceramic of the bottom or of the wall of the frame when the frame is ceramic, * fixing means of the housing on a support, * possibly at least one orifice in the case of optoelectronic housings, * another ceramic plate e associated with semiconductors, this assembly forming the part of the thermoelectric system (Peltier) associated with the ceramic base, characterized in that said method comprises the steps a) of creating raw ceramic sheets by pouring a mineral suspension comprising materials - 31 powder ceramics dispersed in a liquid organic phase formed by a liquid organic matrix and at least one solvent, and by drying the sheets formed to remove the at least organic solvent, b) creation on the plane (X , Y) dried raw ceramic sheets of metal tracks, to form all the conducting circuits, the sealing or soldering tracks and the soldering tracks, by means of a suspension of metallic particles, or ink, formed by dispersion of '' at least one powdery refractory metal, in a liquid organic phase formed by a liquid organic matrix and at least one solvent, then drying of the tracks to evacuate at least one solvent therefrom, 15 c) creation of internal vertical channels or vias in the third dimension (Z), by drilling the dried raw ceramic sheets and filling the channels with an ink or metallization paste consisting of means of a suspension of metallic particles dispersed in a liquid organic phase formed of a liquid organic matrix and of at least one solvent, d) of creating a homogeneous block to form the bottom in raw ceramic by stacking different shaped raw ceramic sheets, cut, provided with their metal tracks and vertical tracks filled with ink, then by compression of the stack and by sintering of the homogeneous compressed ceramic block, at a temperature of at least 1350 ° C. .   e) assembly by soldering on the sintered ceramic bottom of the ceramic or metallic frame and pins - 32 of interconnections at a temperature between 2750C and 8000C, f) assembly by welding of semiconductors of at least 5 a thermoelectric effect regulation and dissipation system (Peltier) on at least one of the external and internal faces of the ceramic background, in line with the tracks initially created, at a temperature between 1300C and 2400C.   2. Method according to claim 1, characterized in that the suspension in a liquid organic phase of powdery ceramic materials, used in the production of curing ceramic sheets, consists of 15 * 50 to 75% by weight of the mixture of powdery ceramic materials essentially consisting of A1203 and / or aluminum nitride, so that after a sintering heat treatment, the alumina and / or aluminum nitride content of the product from sintering contains at least about 92 % by weight of alumina and / or aluminum nitride.   * from 5 to 15% by weight of at least one organic binder, 25 * from 15 to 45% by weight of at least one organic solvent, * from 0 to 5% by weight of at least one plasticizing agent and / or a lubricant.   3. Method according to either of claims 1 or 2, characterized in that the powdery ceramic materials - 33 have a diametrical dimension of the grains preferably between 0.5 and 5 pnm.   4. Method according to any one of claims 1 to 3, characterized in that the organic matrix of the liquid organic phase of the mineral suspension contains at least one organic binder chosen from the group of polymers including polyvinyl butyral, acrylic polymers or methacrylics, acrylates or methacrylates, polyvinyl alcohols, polyolefins.   5. Method according to any one of claims 1 to 4, characterized in that the organic matrix of the liquid organic phase of the mineral suspension contains at least one plasticizing agent chosen from the group consisting of polyalkylene glycols, in particular polyethylene glycol, ethylene glycol, monoethyl ethers of ethylene glycol, alkyl phthalates, dibutylphthalate used alone or as a mixture. 20 6. Method according to any one of claims 1 to 5, characterized in that the liquid organic phase of the mineral suspension contains at least one solvent chosen from the group consisting of alcohols, in particular methyl ethyl ketone, the halogenated solvents in in particular trichloroethane, trichlorethylene taken alone or as a mixture.   7. Method according to any one of claims 1 to 6, characterized in that the raw ceramic sheets, cast and dried, participating in the formation of the ceramic background, receive by printing or coating of metallized conductive tracks, metallized tracks for soldering, sealing and welding by means of a conductive metallic ink - 34 formed of at least one powdery refractory metal dispersed in a liquid organic phase.   8. Method according to any one of claims 1 to 7, characterized in that the raw ceramic sheets once poured and dried, participating in the formation of the ceramic bottom, are provided with vertically shaped holes which are filled with a paste metallic conductive formed of at least one refractory metal pulverulent in a liquid organic phase, forming conductive channels or "vias" allowing, through the various layers of ceramic sheets, to assume the connection between the metallic conductive tracks of the various ceramic layers and 15 all the functions of the communication and interconnection circuits between the internal components and the external environment of the housing.   9. Method according to any one of claims 1 to 8 characterized in that the refractory metals suspended in a liquid organic phase containing at least one organic binder and an organic solvent, used in the ceramic suspension, are chosen from the group consisting of tungsten and molybdenum, used alone or as a mixture.   10. A method according to any one of claims 1 to 9, characterized in that the raw ceramic sheets, shaped and cut to the dimensions of the housing, and provided with their conductive metal tracks and their conductive vertical vias, are stacked in homogeneous blocks, which are subjected to compression and to a sintering operation at a temperature preferably between 14500C and 18000C. - 35   11. Method according to any one of claims 1 to 10, characterized in that the metallic or ceramic frame and the interconnection pins are assembled with the ceramic bottom in line with the tracks initially created, by 5 soldering of the gold / tin type, gold / germanium, silver / copper, between 2750C and 8000C.   12. Method according to any one of claims 1 to 11, characterized in that the assembly of the semiconductors of the 10 at least one regulation and heat dissipation system by thermoelectric effect (Peltier) on at least one of the external and internal faces of the ceramic bottom to the right of the tracks initially created, is made by welding between 1300C and 2400C, by means of compositions based on tin / bismuth, tin / lead, and tin / nickel.   13. Highly hermetic thermo-regulating electronic or optoelectronic boxes of ceramic / ceramic or ceramic / metal type, with a ceramic base, incorporating a thermoelectric (Peltier) regulation and heat dissipation system, by application of any one of claims 1 to 12, characterized in that the ceramic base is at least one cell or a flat plate 25 of which at least one of the faces constitutes one of the plates of at least one system of regulation and of heat dissipation electric (Peltier).   14. Housing according to claim 13, characterized in that the cell forming the ceramic base, in section, has the shape of a U, and creates at least one internal thermoelectric regulation and dissipation system (Peltier). - 36   15. Housing according to claim 13, characterized in that the cell forming the ceramic bottom, in section, the shape of an inverted U and creates at least one thermoelectric regulation and dissipation system (Peltier) external.   16. Housing according to claim 13, characterized in that the cell forming the ceramic base has, in section, the shape of an H and creates at least two internal and external thermoelectric regulation and dissipation systems (Peltier).   17. Housing according to claim 13, characterized in that the external face of the ceramic plate forming the ceramic base creates at least one external thermoelectric regulation and dissipation system (Peltier). 15 18. Housing according to claim 13, characterized in that the external face of the ceramic plate forming the ceramic base creates at least two external thermoelectric regulation and dissipation systems (Peltier), placed side by side and / or superimposed.   19. Housing according to claim 13, characterized in that the external and internal faces of the ceramic plate forming the ceramic base create at least two internal and external thermoelectric dissipation (Peltier) systems.   20. Use of the boxes according to claims 1 to 19, in on-board systems, satellites, missiles, planes, means of public transport, cars, in telecommunications systems, data transmission, in particular relays, terminals, exchanges , in industrial equipment goods and durable consumer goods, 3'7 integrating sensor elements and signal conversion and processing.