WO2010028942A1

WO2010028942A1 - Heterogeneous heat pipe and manufacturing process

Info

Publication number: WO2010028942A1
Application number: PCT/EP2009/060952
Authority: WO
Inventors: Thierry Hilt
Original assignee: Commissariat A L'energie Atomique
Priority date: 2008-09-09
Filing date: 2009-08-25
Publication date: 2010-03-18
Also published as: FR2935787A1; FR2935787B1

Abstract

The heat pipe comprises, in succession, an evaporation zone (2), an adiabatic zone (3) and a condensation zone (4). The adiabatic zone (3) comprises a capillary system (5) that connects the evaporation zone (2) to the condensation zone (4). The evaporation zone (2) and a first portion (5a) of the capillary system (5) are formed in a first element (6), at least partly made of a semiconductor material. The adiabatic zone (3), the condensation zone (4) and a second portion (5b) of the capillary system are formed in a second element (13), made of one or more materials different from the semiconductor material of the first element (6). The first and second elements (6, 13) are placed end to end so as to bring a first sub-cavity (1a) into communication with a second sub-cavity (1b) and are sealed at a junction (18).

Description

Heterogeneous heat pipe and method of manufacture

Technical field of the invention

The invention relates to a heat pipe which successively comprises, in a cavity containing a heat transfer liquid, an evaporation zone, an adiabatic zone and a condensation zone, the adiabatic zone comprising a capillary network connecting the evaporation zone to the zone of condensation, the evaporation zone and a first portion of a capillary network being formed in a first element, at least partly in semiconductor material.

The invention also relates to a method of manufacturing such a heat pipe.

State of the art

Heat pipes are systems that transfer heat to disperse thermal energy over a long distance. They are conventionally in the form of a hermetic enclosure, thermally conductive material, typically made of metal, which contains a liquid in equilibrium with its vapor phase, in the absence of any other gas. The heat transfer takes place passively, by cycles of evaporation of the liquid on a hot part and condensation on a cold part. The liquid condenses on the cold part and returns to the evaporation zone, either by gravity or by a capillary phenomenon. These devices, passive, do not require external energy input. They are used in many applications. They are, in particular, used to evacuate heat in systems where space constraints prevent the use of conventional cooling systems, such as a radiator or an active convection system. More particularly, flat heat pipes with microcapillary network are used in electronic circuits where the miniaturization and the improvement of the performances of the electronic components lead to an increase in the heat density released during operation. Small heat pipes have been developed to meet the size constraints of electronic components. The integration of a heat pipe in an electronic system, close to the heat source, optimizes the heat removal, thus avoiding the degradation of the component.

For example, US-B-6216343, US-B-6167948 and US-A-6158502 disclose capillary network metal heat pipes and their manufacturing process for microelectronics applications.

The document DE202006019275 U1 discloses a heat pipe comprising a porous capillary network of semiconductor material connecting an evaporation zone to a condensation zone.

Furthermore, US-A-5179043 discloses a method of manufacturing triangular or trapezoidal microcalorbs, integrated into the silicon substrate of an electronic component. The use of a silicon heat pipe removes a thermal interface between the semiconductor component and the heat pipe, thus improving the thermal conductivity between the two elements. The capillary network formed remains, nevertheless, limited to simple structures.

Similarly, US-A-4697205 discloses a semiconductor device integrated directly into a heat pipe in the form of a housing, one of whose walls is formed by the semiconductor material.

US-A-5947193 discloses a miniaturized flat heat pipe, made of silicon, having an improved capillary network. The optimized network structure, obtained by plasma etching ("reactive ion etching", denoted RIE), comprises several patterns diffusing the heat transfer fluid in several directions and having forms improving the capillary force. The circulation velocity of the heat transfer fluid inside the heat pipe is thereby increased, thereby improving the efficiency of the heat pipe.

Object of the invention

The aim of the invention is a heat pipe as well as a method of manufacturing such a heat pipe remedying the drawbacks of the prior art. In particular, the invention aims a heat pipe, having good thermal conductivity, compact and inexpensive. It is intended to be easily integrated in an electronic system according to an industrial manufacturing process, easy to implement and economically viable.

According to the invention, this object is achieved by a heat pipe and its manufacturing method according to the indexed claims.

More particularly, this object is achieved by the fact that - the first element comprises a first sub-cavity opening onto a first sealing face,

the adiabatic zone, the condensation zone and a second portion of the capillary network are formed in a second element consisting of one or more different materials of the semiconductor material of the first element, and

the second element comprises a second sub-cavity opening onto a second sealing face, the first and second elements being placed end to end to make the first sub-cavity communicate with the second sub-cavity and being sealed by the first and second sealing faces, at a junction of the first and second parts of the capillary network. According to the invention, the manufacturing method comprises the following steps:

- Realization of the first element from at least one plate of semiconductor material, with etching of the first part of the capillary network of the first element, - Production of the second element with etching of the second part of the capillary network,

hybridising, by sealing, the first element and the second element at their sealing faces after alignment of the first and second parts of the capillary network.

Brief description of the drawings

Other advantages and features will emerge more clearly from the following description of particular embodiments of the invention given by way of non-limiting example and represented in the accompanying drawings, in which:

FIG. 1 represents, schematically and in section, a first particular embodiment of the heat pipe according to the invention; FIGS. 2 and 3 show, schematically and, respectively, in perspective and in section along AA, the first element of the heat pipe; according to Figure 1,

- Figures 4 and 5 show, schematically and respectively in perspective and in section along BB, the second element of the heat pipe according to Figure 1,

FIGS. 6 to 11 show, schematically and in section, different steps of a method of manufacturing the first element according to FIGS. 2 and 3,

FIGS. 12 to 14 show, schematically and in section, different steps of a method of manufacturing the second element according to FIGS.

5 FIGS. 15 and 16 show, schematically and in section, the various stages of hybridization and sealing of the first and second elements of the heat pipe according to FIG. 1,

- Figures 17 to 20 show, schematically and in section, different steps of a method of manufacturing the first element of a second embodiment of the heat pipe according to the invention.

- Figures 21 and 22 show schematically and respectively in top view and in section along CC, a particular embodiment of a second element of a heat pipe according to the second embodiment. FIGS. 23 and 24 show, schematically and in section, the steps of hybridization and sealing of a first element according to FIG. 20 and a second element according to FIGS. 21 and 22,

- Figure 25 illustrates an application of a heat pipe according to the invention.

Description of particular embodiments of the invention

The heat pipe shown in FIG. 1 comprises successively (from left to right in FIG. 1), in a cavity 1 containing a heat transfer fluid, an evaporation zone 2, an adiabatic zone 3 and a condensation zone 4. The adiabatic zone 3 comprises a capillary network 5 which connects the evaporation zone 2 to the condensation zone 4.

The evaporation zone 2 and a first portion 5a of the capillary network 5 are formed in a first element 6, at least partly made of semiconductor material, preferably of silicon. A component to be cooled 7, a source of heat, can be either in contact with an external face of the first element 6, at the level of the evaporation zone 2 of the coolant, initially in liquid form, or directly integrated in the material part. semiconductor of the first element 6, at the level of the evaporation zone 2. The latter solution has the advantage of eliminating the thermal interface between the component to be cooled 7 and the first element 6, thus promoting the diffusion of heat.

As illustrated in FIGS. 2 and 3, the first element 6 comprises the first part 5a of the capillary network and a first sub-cavity 1a, opening onto a first sealing face 8. The first part 5a of the capillary network can advantageously comprise pins 9 at the level of the evaporation zone 2. The presence of the pins 9 increases the solid / liquid contact surface and thus promotes the evaporation of the coolant liquid. The first element 6 is, advantageously, constituted by a first wafer 10 and a second wafer 11 of semiconductor material, sealed to one another at a peripheral edge 12 delimiting the sub-cavity 1 a. The first portion 5a of the capillary network is formed, at least partially, in the first wafer 10, preferably in the two wafers 10 and 11.

In a variant, not shown, only the first wafer 10 is of semiconductor material, the second wafer 11 being of non-semiconductor material. The first part 5a of the capillary network is then entirely formed on the first wafer 10.

The adiabatic zone 3 and the condensation zone 4, as well as a second portion 5b of the capillary network 5, are formed in a second element 13 consisting of one or more different materials of the semiconductor material of the first element 6. For example, the first element 6 is silicon and the second element 13 based on gallium arsenide (AsGa) or indium phosphide (InP) or germanium (Ge).

Advantageously, the second element 13 consists of one or more non-semiconductor materials. Preferably, the second element 13 is made of metal material, ceramic, plastic or material composite. For example, the first element 6 may be silicon and the second element 13 consists of a first portion of iron / nickel alloy and a second portion of copper. The use of a second element 13 consisting of several materials makes it possible to stagger the differences in the expansion of the materials and to compensate the shear stresses on several interfaces.

As represented in FIGS. 4 and 5, the second element 13 comprises the second portion 5b of the capillary network and a second sub-cavity 1b opening onto a second sealing face 14.

When the second element 13 is made of non-metallic material, for example plastic or ceramic, the second sealing face 14 is covered with a metal layer, in order to accommodate the differences in equivalent thermal conductivity (ETC) between the materials. first and second elements 6 and 13 and then ensure a better thermal interface between these elements 6 and 13. The second element 13 preferably comprises two plates 15 and 16, non-semiconductor material, sealed to one another at a peripheral edge 17 delimiting the sub-cavity 1 b. The second portion 5b of the capillary network is formed, at least partially, in the first wafer 15, preferably in the two wafers 15 and 16.

Advantageously, the second element 13 is much longer than the first element 6. Indeed, it is important to use a semiconductor material, essentially at the level of the evaporation zone 2, in contact with the component to be cooled. Preferably, the first element 6 has a size substantially corresponding to that of the evaporation zone 2.

On the other hand, the greater the length of the second element 13, the greater the equivalent thermal conductivity. As represented in FIG. 1, the first and second elements, respectively 6 and 13, are placed end to end, between the evaporation zone 2 and the adiabatic zone 3, to make the first sub-cavity 1a communicate with the second sub-cavity 1a. -cavity 1 b. In particular, the first and second elements, respectively 6 and 13, are placed end to end in the direction of a direction defined by the direction of the vapor flow, from the evaporation zone 2 to the condensation zone 4. As an example illustrated in Figure 1, the first and second elements, respectively 6 and 13 are put end to end in the direction of the length of the heat pipe.

At the junction 18 of the two elements 6 and 13, the patterns of the first part 5a of the capillary network correspond to those of the second part 5b of the capillary network, so as not to break the continuity of the capillary network. The junction 18 ensures the continuity of the capillary network 5. Advantageously, the structures of the first and second parts 5a and 5b of the capillary network 5 are similar at least at the junction 18 and connected end to end, as illustrated in FIGS. 5. The capillary network 5 may consist of grooves and / or ribs and / or pores on at least one inner face of each element 6 and 13. The grooves and / or ribs of the capillary network 5 are advantageously arranged perpendicular to the sealing faces 8 and 14, at least near the junction 18, to allow exact alignment between the grooves and / or ribs.

In the preferred embodiment illustrated in FIG. 3, the first part 5a of the capillary network has grooves and / or ribs going from the first sealing face 8 to the evaporation zone 2. It preferably also comprises pins 9 at the evaporation zone 2. The grooves and / or ribs may form an arc at the end of the network close to the evaporation zone 2, to diffuse the heat transfer fluid closer to the hot zone, improve the distribution of the fluid in this zone 2 and thus promote its evaporation.

The respective sub-cavities 1a and 1b of the elements 6 and 13 must be large enough to provide a sufficient volume for the passage of the vapor stream. The flow of steam must not be impeded by the flow of heat transfer liquid in the capillary network 5, from the condensation zone 4 to the evaporation zone 2, in order to avoid a drying phenomenon. A particular structure of the capillary network 5, in particular a semi-enclosed channel structure, for example, delimited by mushroom-shaped elements, partially isolating the vapor zone from the liquid zone, as described in patent US-A-6056044 , can also be considered to minimize this effect.

For example, a heat pipe having a flat tube shape 6 cm long and 1 mm thick was made with a first element 6 0.5 cm long and a second element 13 5.5 cm long, comprising an adiabatic zone 3 of 4 cm long and a condensation zone 4 of 0.5 cm long. The grooves have, for example, a height of about 200 microns. In the elements 6 and 13, of the type shown in FIGS. 2 and 4, a space of approximately 300 μm vertically separates the grooves formed in the wafer 10 or 15, grooves formed in the wafer 11 or 16.

The heat pipe described above combines the advantages of conventional metal heat pipes and silicon heat pipes. Indeed, the fact of using a first element 6 of semiconductor material, allows for an improved thermal interface between the evaporation zone 2 and the heat source. When the heat source is also of semiconductor material, the equivalent thermal conductivities (ETC) of the first element 6 and the heat source are compatible, thus ensuring a better thermal interface. Current silicon etching processes offering possibilities for producing very fine patterns, up to 10 μm, it can also be envisaged to make a complex capillary network 5 in order to optimize solid / liquid heat exchanges within the evaporation zone 2, difficult to envisage for metallic materials.

In addition, since the second element 13 consists of one or more different materials of the semiconductor material of the first element 6, it may be envisaged to produce, at lower cost, a second element 13 long enough to provide a high thermal conductivity and able to be an integral part of a box-type electronic system.

The process for manufacturing the heat pipe described above preferably comprises the simultaneous production of several first elements 6, and after the production of at least one second element 13, the hybridization of the elements 6 and 13 at their level. respective sealing faces 8 and 14. The collective manufacturing method of the first elements 6 and possibly the second elements 13 allows to manufacture the heat pipe on an industrial scale.

The manufacturing method illustrated by way of example in FIGS. 6 to 16 is particularly suitable for the manufacture of flat heat pipes, according to FIGS. 1 to 5. Such a flat heat pipe is used in devices in which the size of the component is critical.

This manufacturing method comprises, firstly, the simultaneous production of a plurality of elements 6 from two plates 19 and 20 of semiconductor material. One of the plates (19 in FIGS. 6 to 10) is, preferably, thicker than the other plate 20. To form the sub-cavities 1 a, a first deep etching is performed in one face (upper on the FIG. 6) of the two plates 19 and 20, so as to delimit open spaces 21a, separated by edges 22. The first parts 5a capillary networks are then etched, preferably by plasma etching of the RIE type. The grooves and / or ribs of the capillary networks 5a thus formed extend horizontally in the plane of FIGS. 6 to 11. Finally, the two plates 19 and 20 are sealed by the edges 22, so as to make the spaces 21a coincide with each other. two plates 19 and 20 and form closed spaces 21 (Figure 7). Each closed space 21 is then opened by a cutout 23 perpendicular to the plates 19 and 20 (vertically in FIG. 8). This makes it possible to release the first sealing faces 8 (vertical in FIG. 8) of the plates 19 and 20, of each first element 6. The cutout 23 completely traverses the plate 20 and partially the plate 19. An electrolytic deposition of braze, preferably without flux, a brazing material 24, for example a gold / tin alloy (AuSn), is produced to obtain a layer of conductive metal, at least on the sealing faces 8. This deposit is made by directional deposition oblique (in a direction indicated by arrows in Figure 9) relative to the outer face (horizontal in Figure 9) of the plate 20. In practice, the deposition is simultaneously on the outer face of the plate 20 and on the sealing faces 8 of the plates 19 and 20. Advantageously, a germination layer promoting the electrolytic deposition is previously deposited by directional deposition at the same oblique angle, on the sealing faces 8 and r the outer face of the plate 20, for example, by directional metal deposition. Then, the assembly constituted by the plates 19 and 20 is turned over and placed on an adhesive film 25, as shown in FIG. 10, the thinner plate 20 being in contact with the film 25. The first elements 6 are then separated each other, for example, by thinning the rear face of the plate of semiconductor material 19 (Figure 11).

Alternatively, the plate 20 may be of non-semiconductor material. The first parts 5a of the capillary networks can be realized only on the semiconductor material plate 19, intended to be in contact with the component to be cooled 7.

Moreover, the spaces 21a can be etched in only one of the plates 19 or 20.

The second elements 13 are preferably also collectively formed, as shown in FIGS. 12 to 14. Several second elements 13 are made, simultaneously, from two plates 26 and 27, made of one or more different materials of the semiconductor material of the first element, advantageously of non-semiconductor material. To form the sub-cavities 1b, a first deep etching is performed in one face (upper in FIG. 12) of each of the plates 26 and 27, so as to delimit open spaces 28a, separated by edges 29. parts 5b of the capillary networks are etched on at least one of the two plates 26 and 27. As for the production of the first elements 6, the cavities 1b can be made only on one of the plates 26 or 27 and the second parts 5b of the networks, on the other plate 26 or 27. Any conventional etching technique, adapted to the material used, can be used. For example, the etching can be performed by lithography, electrochemical etching, plastic injection or electroerosion from tungsten carbide tool. The two plates 26 and 27 are then sealed by their edges 29, so as to make the spaces 28a of the two plates 26 and 27 coincide and form second channel-like spaces 28 open at their two ends, parallel to the plane of FIG. 13. One of the ends 30 of the assembly constituted by the plates 26 and 27 is intended to form the sealing faces 14 and may be metallized with a brazing material 24, for example by depositing a conductive metal layer, preferably, gold alloy / tin (Figure 14). This metallization is necessary only for non-metallic plates 26 and 27, for example, ceramic or plastic. Openings 32, opening on the other end of the assembly 31, are intended for subsequent filling of the cavities 1 (FIG. 15).

The first elements 6 are positioned on the end 30, possibly metallized, in order to make each first sub-cavity 1a coincide with a second sub-cavity 1b. The first parts 5a of the capillary networks are then aligned on the corresponding second portions 5b, capillary networks. The alignment is, advantageously, an optical alignment ensuring a perfect connection of the first and the second part 5a and 5b of each capillary network. From this connection depends the continuity of the flow, therefore the flow velocity and, consequently, the heat removal efficiency of the heat pipe. The first and second elements 6 and 13 are then hybridized, by sealing, at their sealing faces 8 and 14, for example, by soldering or gluing. Sealing by soldering is performed by depositing a brazing material 24 on at least one sealing face 8 and 14 before hybridization, then exerting pressure, advantageously on the first elements 6 and then heating the solder zone. In this preferred embodiment, several first elements 6, positioned on a set 31, are hybridized simultaneously. The successive manipulations of the first elements 6 may be carried out using pre-emption heads, preferably by suction. As shown in FIG. 15, the cavities 1 thus formed are then evacuated simultaneously, in a collective manner, by the openings 32 of the second elements 13. Finally, the openings 32 are sealed, after partial filling (FIG. cavities 1 by the coolant, for example, by water, ammonia or glycol. The heat pipes are then individualized by cutting plates 26 and 27 of the assembly 31. The collective realization of the first elements 6, on the one hand and the second elements 13, on the other hand, as well as the simultaneous hybridization of several first elements 6 on the corresponding second elements 7 make it possible to envisage the industrial manufacture of such heat pipes. .

Another embodiment of the method for manufacturing a heat pipe illustrated by way of example in FIGS. 17 to 24 is particularly suitable for the manufacture of a heat pipe according to FIG. 24. Such a heat pipe is, more particularly, used for devices in which the size of the component to be cooled 7 is not critical. The second element 13, shown in FIGS. 21 and 22, can be an integral part of a housing.

A plurality of first elements 6, as shown in FIG. 20, is produced from a plate 19 made of semiconductor material, by successive etching of the sub-cavities 1a opening onto the first sealing faces 8 and the first parts 5a of the networks. capillaries (Figure 17). A brazing material 24, for example a gold / tin alloy (AuSn), can then be deposited (FIG. 18) by electrolytic deposition of solder, preferably without flux, on the sealing faces 8 of the first elements 6. A layer The electrolytic deposition-promoting nucleation is then advantageously deposited on the sealing faces 8 before the electrocatalytic deposition of solder. The plate 19 is then turned over and placed on an adhesive film 25, as shown in Figure 19. The first elements 6 are then separated by cutting the plate 19 as shown in Figure 20. The adhesive film 25 can then be removed. Each first element 6 is then hybridized with a second element 13 represented in FIGS. 21 and 22. This element 13 has a sub-cavity 1b opening on its sealing face 14 (upper face in FIG. 22) of the second element 13. It comprises an opening 32 constituting a closure orifice on a lateral face (right lateral face in FIG. 22). As before, the sealing face 14 can be metallized if the second element 13 is non-metallic, for example, ceramic or plastic material.

The sealing face 8 of the first element 6 is positioned on the sealing face 14 of the second element 13, possibly metallized, in order to make the first sub-cavity 1a coincide with the second sub-cavity 1b. As before, the successive manipulations of the first element 6 are carried out using pre-emption heads, preferably by suction. The first part 5a of the capillary network is then aligned with the second part 5b of the capillary network. Then, as shown in FIG. 23, the first and second elements 6 and 13 are individually hybridized, at their sealing faces 8 and 14, either by brazing or by gluing. The alignment is, advantageously, an optical alignment ensuring a perfect connection of the first and second parts 5a and 5b of the capillary network at their junction 18. As previously, the cavity 1 thus formed is evacuated by the opening 32 the second element 13 and partially filled with the coolant. The opening 32 is finally sealed (Figure 24) to obtain the heat pipe.

The use of the heat pipe described above finds its interest in systems where space constraints are important, especially in flat systems, but also in portable systems requiring energy autonomy. Figure 25 shows an example of application of a heat pipe integrated in a mobile phone. The evaporation zone 2 is located at the component or components to be cooled (at the top in FIG. 25) and the adiabatic zone 3 is sufficiently long to evacuate the heat evolved by the component (s) to be cooled. The condensing zone 4 is located in the lower part of the portable in FIG.

Many applications can be envisaged, in particular for the cooling of emission laser diodes in which the densities of power are high and in the case of systems having to respect severe environmental and dimensional constraints.

Claims

claims

1. Heat pipe comprising successively in a cavity (1) containing a heat transfer fluid, an evaporation zone (2), an adiabatic zone (3) and a condensation zone (4), the adiabatic zone (3) comprising a network capillary (5) which connects the evaporation zone (2) to the condensation zone (4), the evaporation zone (2) and a first portion (5a) of a capillary network

(5) being formed in a first element (6), at least partly made of semiconductor material, heat pipe characterized in that the first element

(6) comprises a first sub-cavity (1 a) opening onto a first sealing face (8), in that the adiabatic zone (3), the condensation zone (4) and a second part (5b) of the network capillary (5) are formed in a second element (13) consisting of one or more different materials of the semiconductor material of the first element (6), and in that the second element (13) comprises a second sub-cavity (1). b) leading to a second sealing face (14), the first (6) and second elements (13) being placed end to end to communicate the first sub-cavity (1 a) with the second sub-cavity (1 b). ) and being sealed by the first (8) and second sealing faces (14), at a junction (18) of the first (5a) and second portions (5b) of the capillary network (5).

2. Heat pipe according to claim 1, characterized in that the first (5a) and second portions (5b) of the capillary network (5) have similar structures at least at the junction (18) and are connected end to end.

3. Heat pipe according to one of claims 1 and 2, characterized in that the second element (13) consists of one or more non-semiconductor materials.

4. Heat pipe according to claim 3, characterized in that the second element (13) is made of metallic material.

5. Heat pipe according to claim 3, characterized in that the second element (13) is made of non-metallic material, with a metal layer

(24) on the second sealing face (14).

6. Heat pipe according to any one of claims 1 to 5, characterized in that the capillary network (5) has grooves and / or ribs and / or pores on at least one inner face of each element (6, 13). ).

7. Heat pipe according to claim 6, characterized in that the grooves and / or the ribs of the capillary network (5) are perpendicular to the sealing faces (8, 14), at least near the junction (18).

8. Heat pipe according to any one of claims 1 to 7, characterized in that at least one of the element (6, 13) comprises a first plate (10, 15) and a second plate (11, 16), sealed to one another at a peripheral border (12, 17) delimiting the sub-cavity (1a, 1b) of said element (6, 13), the first and second parts (5a, 5b) corresponding capillary network (5) being formed, at least partially, in the first wafer (10, 15).

9. Heat pipe according to claim 8, characterized in that the first plate (10) of the first element (6) is of semiconductor material.

10. Heat pipe according to any one of claims 1 to 9, characterized in that the first portion (5a) of the capillary network (5) comprises pins (9) at the evaporation zone (2).

11. Heat pipe according to any one of claims 1 to 10, characterized in that a component to be cooled (7) is integrated in the semiconductor material part of the first element (6), at the level of the evaporation zone ( 2) heat pipe.

12. A method of manufacturing a heat pipe according to any one of claims 1 to 11, characterized in that it comprises the following steps:

- Making said first element (6) from at least one plate (19) of semiconductor material, with etching of the first part (5a) of the capillary network (5) of the first element (6),

- Realizing said second element (13) with etching of the second portion (5b) of the capillary network (5),

- Hybridization, by sealing, of the first element (6) and the second element (13) at their sealing faces (8, 14) after alignment of the first and second parts of the capillary network (5a, 5b).

13. Manufacturing process according to claim 12, characterized in that the second element (13) is made from two plates (26, 27) made of one or more different materials of the semiconductor material of the first element (6). ).

14. The manufacturing method according to one of claims 12 and 13, characterized in that the first and / or second elements (6, 13) are made collectively.

15. Manufacturing process according to any one of claims 12 to 14, characterized in that the seal is obtained by soldering or gluing.

16. The manufacturing method according to claim 15, characterized in that the seal being made by brazing, a brazing material 24 is deposited on at least one sealing face (8, 14) before hybridization.

17. The manufacturing method according to any one of claims 12 to 16, characterized in that said second element (13) initially having an opening (32) for filling the cavity (1), the method comprises, after hybridization, evacuating the cavity (1) with said opening (32) of the second element (13) and sealing said opening (32) of the second element (13) after partial filling of the cavity (1) with the coolant .