CH716692A2 - A method of manufacturing a silicon component, typically watchmaking. - Google Patents

Abstract

The invention relates to a method of manufacturing at least one component, typically watchmaking component (3), comprising the following steps: a) providing a female part (1) comprising at least one opening (4) and a counterbore ( 5) bordering this opening (4) and a male part (2) comprising a shoulder (7), b) insert at least part of the male part (2) into the opening (4) so that the counterbore (5) and the shoulder (7) abut against each other to axially position the male (2) and female (1) parts with respect to each other, at least the part of the male part (2) located opposite the opening (4) and / or the part of the female part (1) defining the opening (4) being made of silicon optionally covered with silicon oxide, said parts leaving between them a free space (8), c) subjecting all of said male (2) and female (1) parts to a heat treatment so that on the surface of at least one of said parts a layer forms he silicon oxide at least partially filling said free space (8), d) continuing step c) at least until said two parts (1, 2) join together to form said component (3) .

Description

The present invention relates to a method of manufacturing a component, typically watchmaking, at least partly in silicon, comprising the assembly of two parts, said component may be of complex shape, in particular multi-level.

[0002] In watchmaking, monolithic silicon components are mainly used. Such components can be obtained by etching, for example by chemical etching or by deep reactive ionic etching (DRIE). This technique, on its own, that is to say not followed by assembly steps, is difficult to apply for obtaining components with a complex structure such as multi-level components. Indeed, at least one assembly step seems preferable for the manufacture of such components.

[0003] In micromechanics, there is a technique for manufacturing components by assembling silicon parts known under the name of “fusion bounding”. This technique creates a covalent bond between superimposed flat surfaces of two silicon parts. To do this, the flat surfaces of these parts undergo an activation step comprising a surface treatment before being positioned and aligned one opposite the other and then brought into contact. The surface treatment can typically consist of an acid cleaning to remove the native oxides and release ions or else in an ionic activation, for example by bombardment. This preliminary activation step allowing the formation of a covalent bond between the flat surfaces in contact with the parts is followed by a thermal oxidation step leading to the formation of a silicon oxide layer or coating on the surfaces. assembly of parts. A component consisting of said two assembled parts can thus be obtained. This method has the drawback of requiring a step of activating the surfaces as well as a relatively precise prior alignment.

Assembly techniques such as bonding or brazing are used for the production of components of complex shapes in silicon. However, these techniques are not optimal in that they require the application of a layer of glue or of a metal for the assembly as well as a very precise positioning of the parts to be assembled with respect to one another. other before their assembly. In addition, the components thus obtained may have restrictions as to their conditions of use, these restrictions depending in particular on the resistance of said layer to certain temperature, humidity or other conditions.

An object of the present invention is to provide a method of manufacturing a component, typically micromechanical, at least partly in silicon by assembling two parts, which can be implemented simply, which is suitable for manufacturing components of complex shapes, in particular multi-level and which makes it possible to obtain a resistant component.

The invention provides for this purpose a method of manufacturing at least one component comprising the following steps: a) providing a female part comprising at least one opening and a countersink bordering this opening and a part male comprising a shoulder, b) inserting at least part of the male part into the opening so that the counterbore and the shoulder abut against each other to axially position the male and female parts together with respect to the other, at least the part of the male part located opposite the opening and / or the part of the female part defining the opening being made of silicon optionally covered with silicon oxide, said parts leaving between they a free space, c) subjecting all of said male and female parts to a heat treatment so that, on the surface of at least one of said parts, forms a layer of silicon oxide filling at least part of said free space, d) continue step c) at least until said two parts join together to form said component.

[0007] Advantageously, said component is a micromechanical component.

[0008] The invention relates more particularly to a method of manufacturing a watch component, typically intended to be inserted into a watch case such as a wristwatch.

[0009] The male and female parts used in the method according to the invention are typically obtained by etching, for example by deep reactive ionic etching DRIE, by laser etching or by chemical etching, preferably by DRIE etching.

[0010] The expression "micromechanical component" typically designates a component of which at least one of the dimensions is less than 1mm.

[0011] In the context of the invention, the silicon can be monocrystalline, regardless of its crystalline, polycrystalline or amorphous orientation. It may or may not be doped.

As indicated above, the part of the female part defining the opening and / or the part of the male part located in the opening at the end of step b) can be made of silicon covered with silicon oxide, and this prior to step c). This silicon oxide can be native or resulting from a preliminary thermal oxidation step with the aim of reinforcing the mechanical strength of the male and female parts.

[0013] In the context of the invention, the expression "female part" includes any part intended to receive another part, more precisely any part comprising at least one opening capable of receiving at least part of a male part. The expression “male part” for its part includes any part intended to be introduced, at least in part into a female part, more precisely any part comprising at least one part capable of being introduced into an opening of a female part. Typically, in an assembly of two parts one inside the other, the one which must be placed at least partly inside the other is called the "male part" and the one which receives at least part of the male part. is called "female part".

The manufacturing method according to the invention can be implemented simply, in particular without prior treatment of the parts to be assembled and without requiring a device for positioning the parts, and makes it possible to obtain components of complex shapes, typically comprising more than two levels, typically at least three, preferably at least four, or even more than four levels. It makes it possible to obtain components having good mechanical resistance and which are little or not influenced by variations in environmental conditions such as temperature or humidity. The method according to the invention is also reliable and has good reproducibility.

Other characteristics and advantages of the present invention will become apparent on reading the following detailed description given with reference to the appended drawings in which: FIG. 1 represents, in top view, a female part for the implementation of 'a particular manufacturing process according to the invention. FIG. 2 represents, in perspective, a male part for implementing said particular manufacturing method according to the invention, said male part being intended to be assembled to the female part of FIG. 1 using this method. FIGS. 3 and 4 are views in longitudinal section showing successive steps of said particular manufacturing method according to the invention. We see there the female and male parts appearing respectively in Figures 1 and 2. Figure 5a shows, in longitudinal section, a component obtained by assembling the parts illustrated in Figures 1 and 2 using said particular manufacturing process according to l 'invention. FIG. 5b represents, in longitudinal section, the component obtained from the component illustrated in FIG. 5a by continuing step c) of said particular manufacturing method according to the invention a little longer. Figures 6a, 6b and 6c respectively illustrate, in perspective, a female part, a male part and a component corresponding to a part of a watch resonator assembled from these parts using a particular manufacturing process according to invention.

A first step a) of a method according to a preferred embodiment of the invention consists in providing a female part 1, and a male part 2, in silicon, as shown respectively in figures 1 and 2. These two parts 1, 2 are intended to be assembled to manufacture a component 3, typically micromechanical.

The female part 1 typically comprises a through cylindrical opening 4 of diameter d1 and a countersink 5 at the entrance of this opening 4, as illustrated in Figures 1 and 3.

The male part 2 typically comprises a cylindrical rod 6 of diameter d2 less than d1 and a head forming a shoulder or collar 7 at one end of this rod 6, as illustrated in Figures 2 and 3.

In a subsequent step b) of said method, illustrated in Figure 3, the rod 6 of the male part 2 is inserted into the opening 4 until its shoulder 7 abuts against the countersink 5 of the female part 1.

The diameter d2 of the rod 6 is slightly less than that d1 of the opening 4 so that, when inserted into the opening 4, there is a free space 8 between the rod 6 and the part of the female part 1 defining the opening 4.

At the end of step b), the rod 6 can be slightly off-center. This has no effect, it can be centered during subsequent steps of the method according to the invention. At the end of step b), the distance separating the surface of the part of the rod 6 located inside the opening 4 from the surface of the part of the female part defining the opening 4, when the rod 6 is considered centered in the opening 4, is denoted d3.

The counterbore 5 and the shoulder 7 constitute positioning means cooperating together to axially position the female 1 and male 2 parts relative to each other. They participate in maintaining these parts in a given axial position during the subsequent steps of the method according to the invention. They also have several other advantages which will be described later.

Once the female 1 and male 2 parts are positioned axially relative to each other, that is to say once the shoulder 7 of the male part 2 is in abutment against the countersinking 5 of the female part 1 (FIG. 3), a heat treatment step c) makes it possible, by a thermal oxidation reaction, to form, on each of the male and female parts made of silicon, a layer of silicon oxide , typically silicon dioxide (SiO2).

During this step c), the assembly formed by the female 1 and male 2 parts is therefore subjected to a heat treatment, typically at a temperature between 800 ° C and 1300 ° C, in an oxidizing atmosphere, by example comprising water vapor, until a layer of silicon oxide of predetermined thickness e is obtained on the surfaces of the male and female parts.

[0025] The heat treatment is typically carried out in an oxidation furnace. It is preferably carried out at a temperature between 950 ° C and 1150 ° C.

The silicon oxide layer is formed by consuming silicon over a depth p corresponding to approximately half of its thickness e.

The molar volume of silicon oxide being greater than that of silicon, this reaction increases the volume of each of the male and female parts, which causes, among other things, the narrowing of the diameter d1 of the opening 4 and increasing the diameter d2 of the rod 6. The free space 8 separating the outer surface of the rod 6 and the inner surface of the opening 4 fills with silicon oxide as the reaction d thermal oxidation is evolving.

The thermal oxidation reaction is controlled and its kinetics are the same on all the surfaces of the male 2 and female 1 parts so that, as the thermal oxidation reaction evolves, the rod 6 is centered in opening 4, even if it was not initially centered. The counterbore 5 - shoulder 7 cooperation ensures good axial and radial positioning (self-centering) of the part before and during the heat treatment and thus a homogeneous growth of the silicon oxide layers leading to solid and reproducible parts. No radial positioning means, whether integral with the male and / or female parts or else independent, and whose action could be altered by the heat treatment, is necessary for the centering.

In a step d), the thermal oxidation reaction is continued at least until a time tmin after which the outer surface of the rod 6 merges with the inner surface of the opening 4, the male parts 2 and female 1 joining together to form a single block of material corresponding to component 3. The joining of the parts is typically due to mechanical clamping and / or to the creation of chemical bonds between the parts.

At this stage, the thermal oxidation reaction can be stopped to recover the final component 3. This component 3, for which the heat treatment was continued for a time tmin, is illustrated in Figures 4 and 5.

During this manufacturing process, precise centering of the male part 2 in the female part 1 is very important, in particular when manufacturing watch components. The cooperation of the counterbore 5 of the female part 1 and of the shoulder 7 of the male part 2 plays an important role in the accuracy of the centering. Indeed, the centering is all the more precise than the height "h" (illustrated in FIG. 3) on which the male part 2 is radially facing the opening 4 when its shoulder 7 is in abutment against the counterbore 5. of the female part 1 (typically at the end of step b)) is large. A large height "h" also guarantees the solidity and reproducibility of the manufactured components.

The internal edges 4a, 5a of the female part 1 and external 6a, 7a of the male part 2 obtained by DRIE etching are not strictly vertical but have slight angles δ, relative to the vertical. These angles, called “relief angles”, are inherent in the engraving techniques used and are low, of the order of approximately 1 ° to 3 °; they are not visible in Figures 1 to 5b. Although small, when they extend over a height of several mm, these relief angles can lead to an increase in the distance d3 by several micrometers and therefore extend the heat treatment time necessary to secure the parts together.

If the female part 1 did not include countersinking, one possibility to adjust the height "h" would be to adjust the height of the opening 4. Likewise, if the male part 2 did not include a shoulder, a possibility to adjust the height "h" would be to adjust the depth of the countersink 5. Thanks to the cooperation of the shoulder 7 of the male part 2 and the countersink 5 of the female part 1, the height "h" can be adjusted in acting on the one hand on the height on which the outer edge 7a of the shoulder 7 and the inner edge 5a of the counterbore 5 of the opening 4 are opposite at the end of step b) and on the other hand on the height on which the outer edge 6a of the rod 6 and the inner edge 4a of the opening 4 are opposite at the end of step b). Thus, for a given distance d3, the presence of both the counterbore 5 of the female part 1 and the shoulder 7 of the male part 2 makes it possible to increase the height "h" on which the parts will be joined and thus d '' obtain a solid final component, with good centering, and good reproducibility of their manufacturing process.

Component 3 obtained at the end of steps a) to d) is completely covered with a layer of silicon oxide so that we can no longer distinguish the male 2 and female 1 parts that it comprises. It has improved mechanical strength compared to a silicon component not covered with a silicon oxide layer. Indeed, silicon oxide is more resistant to mechanical stresses than silicon.

The dotted lines 9, 10 shown in Figure 4 illustrate the position of the contours of each of the female 1 and male 2 parts before the thermal oxidation reaction. The part shown in gray in FIG. 4 represents for its part the portion 11 of component 3 comprising silicon oxide after the heat treatment step. As indicated above, it can be seen that this portion 11 extends over a depth p inside the initial outline of the male 2 and female 1 parts, which illustrates the consumption of silicon during the thermal oxidation reaction.

Those skilled in the art are able to adjust the initial distance d3 as a function of the thickness d4 of the silicon oxide layer desired at the junction between the male 2 and female parts 1. For example, if we consider that the silicon oxide layer is formed by consuming silicon over a predetermined depth p corresponding to approximately half of its thickness e, d4 is equal to approximately twice the value of d3.

In the example illustrated in Figures 1 to 5b, the value of d3 can vary between 1 and 20 microns, preferably between 2 and 8 microns, and the value of d4 for component 3 shown in Figure 4 can vary between 0.5 and 10 µm, preferably between 1 and 4 µm.

In a variant of the method according to the invention, it would be possible to extend step d) of heat treatment beyond tmin. Extending the heat treatment time would make it possible to further thicken the silicon oxide layer coating component 3 and therefore to further strengthen its mechanical strength. FIG. 5b illustrates component 3 'obtained from component 3 illustrated in FIG. 5a by continuing step c) a little longer.

In the particular method described above and illustrated in Figures 1 to 5b, the female 1 and male 2 parts are entirely composed of silicon and no particular treatment has been applied to these parts prior to steps c) and d) of heat treatment. A silicon oxide layer therefore forms on all of the surfaces of these parts, and they therefore increase in volume over all of their surfaces.

On reading the above, it is easily understood that the radial increase in the volume of the rod 6 and therefore the increase in d2 or the radial decrease in the opening 4 and therefore the decrease in d1 would be sufficient for join the two parts together.

Also, in a variant of the method according to the invention, only the part of the female part 1 defining the opening 4 and / or the part of the male part 2 located inside the opening 4 could be cover with a layer of silicon oxide during steps c) and d), the rest of these parts being able to be protected from the thermal oxidation reaction by a typically chemical barrier. For example, a layer of silicon nitride can be produced on at least one surface of one or each of the male 2 and female 1 parts, prior to steps c) and d), to prevent the growth of a layer of oxide on said at least one surface. More generally, it is clear that the formation of a layer of silicon oxide at least on the part of the male part 2 located in the opening 4 or on the part of the female part 1 defining the opening 4 would be sufficient for joining the parts, the male 2 and female 1 parts used can therefore be made of composite material, namely, in part (at least the part of the male part 2 located in the opening 4 or the part of the female part 1 defining the opening 4) in silicon and partly in one or more other materials resistant to steps c) and d) of heat treatment such as quartz, ceramics, silicon carbide, glasses, nitrides in particular silicon nitride. For the reasons mentioned above, it is also possible that only one of these two parts is totally or partially made of silicon.

The method according to the invention is equally applicable to male and female parts of which all or part of the silicon is already covered with silicon oxide prior to the implementation of steps c) and d) of said method , this silicon oxide possibly being native or resulting from a preliminary thermal oxidation step. The rate of the thermal oxidation reaction of silicon decreases with increasing thickness of the silicon oxide layer covering the silicon. Also, in the case where the silicon of the starting male 2 and / or female 1 parts is already covered with silicon oxide, the method according to the invention will potentially take longer to implement.

In the context of the present invention, it is possible to provide male and female parts entirely made of silicon and covered with silicon oxide everywhere except at least on the part of the male part located in the opening and / or on the part of the female part defining the opening. Thus, during the implementation of steps c) and d) of the method, the oxide layer will form more rapidly in the free space where it allows the parts to join together than on the rest of the component. Such a possibility can be used, for example, to limit the magnification of the parts during their assembly.

It will be clear to those skilled in the art that the present invention is in no way limited to the embodiments presented above and illustrated in the figures.

It is obvious that the shape of the male and female parts to be assembled can vary infinitely as long as their functions are fulfilled, that is to say as long as the female part includes an opening bordered by a countersink and that the male part comprises a shoulder and is able to be inserted at least in part into said opening until its shoulder abuts against the counterbore bordering this opening.

In a variant of the method according to the invention, the opening 4 of the female part 1 can be different from a through cylindrical opening, it can be any type of opening, typically cylindrical to non-circular section, for example semi-circular or even non-cylindrical, through or not.

The rod 6 of the male part 2 can also take another form than that described above. It can typically be replaced by a cylindrical rod with a non-circular section, for example semi-circular or even non-cylindrical. The male part 2 may even not include any rod from the moment when it is able to be inserted at least in part into the opening of the female part and where it comprises a shoulder 7 intended to cooperate with the counterbore 5 of the part. female 1.

Advantageously, the shapes of the part of the male part introduced into the opening of the female part and of the opening of the female part, are complementary, that is to say they are identical. Their dimensions are obviously different, the male part having to be introduced into the opening of the female part.

When the part of the male part introduced into the opening of the female part and the opening of the female part have different shapes, d3 corresponds to the minimum distance between the surface of the part of the male part located in the opening and the surface of the part of the female part defining the opening, when the male part is centered in the opening.

The manufacturing method according to the invention typically allows the production of watch components at least partly in silicon such as an anchor, a balance, an oscillator, a spiral spring, a wheel, a lever, a pivot, a cam, these watch components possibly comprising one or more elastic or bistable members. The method according to the invention can be used for the manufacture of all kinds of watch components, said components having or not having a multi-level structure.

For example, the method according to the invention can be used to assemble an anchor on a tree or to fix a stinger to it. It can be used for assembling a balance on a shaft, for fixing pins intended for fixing adjustment weights on a balance (for example on a Gyromax® Patek Philippe type balance), for the assembly of 'a piton on a spiral spring or a wheel and / or a pinion on a shaft. The method according to the invention can also be used for assembling a pin on a watch resonator, said pin being intended to cooperate with a fork of an escapement for maintaining oscillations. This includes in particular the manufacture of a watch resonator as described in European patent application EP3502784, the content of which is incorporated by reference. Figures 6a, 6b and 6c illustrate an example of such an assembly. FIG. 6a illustrates a part 21 of a watch resonator corresponding to a female part. FIG. 6b illustrates a male part 22 comprising a rod 26 of semi-cylindrical shape connected to a protuberance 27 constituting a pin intended to cooperate with a fork of an escapement. The opening 24 of said female part is of substantially identical shape to that of the rod 26. However, it is widened by two shaped ears corresponding to cylinder portions, said ears being intended to face the two longitudinal edges of the stem 26. These ears are optional. Their purpose, although the rod 26 has dimensions smaller than those of the opening 24 in order to be able to be inserted therein, to avoid damaging one of the male 22 and female 21 parts during their assembly. The opening 24 is also bordered by a countersink 25 intended to cooperate with the shoulder of the protuberance 27 for the axial positioning of the parts relative to one another.

For the assembly of these two parts, the rod 26 is inserted into the opening 24 until the protuberance 27 abuts against the counterbore 25 (step b) of the method according to the invention). Steps c) and d) of the method as described above are then implemented to form a watch resonator in one piece, part of which 23 is illustrated in FIG. 6c. The cooperation of the counterbore 25 and the shoulder formed by the protuberance 27 ensures good axial and radial positioning of the parts with respect to each other throughout the heat treatment. These elements make it possible to obtain resistant parts with a precise structure.

According to a typical implementation of the method described above, several components are formed simultaneously from silicon wafers or "wafers". To do this, in the first step a) of the method according to the invention, a first plate is provided comprising a certain number n (n being an integer, greater than or equal to two) of female parts identical to the part. female illustrated in Figure 1 and a second plate typically comprising the same number n of male parts identical to the male part 2 illustrated in Figure 2. The female parts are typically connected to each other and to the rest of their plate by bridges of matter. In the same way, the male parts are connected to each other and to the rest of their plate by material bridges.

The male and female parts are arranged in the plates so that, to each rod of a male part of the second plate corresponds an opening of a separate female part of the first plate, the latter facing each other so that each rod can be inserted into the corresponding opening of the first plate without it being necessary to separate the parts from the plates.

In step b) of said method, the first and second plates are positioned so that the rod of each male part of the second plate is introduced in the same way into the opening of a separate female part of the first wafer.

The two plates are then subjected to a heat treatment so that each of the assemblies comprising a male part and a female part obtained at the end of step b) is subjected to steps c) and d) to form n components.

Typically, the male and female parts remain attached to their respective plates by the material bridges during steps a) to d) of the process, therefore in particular during the insertion of the rods into the openings and during the heat treatment. They are not detached from the wafers until the end of the process, after the heat treatment has been interrupted.

It is possible to have a first wafer comprising more, less or as many female parts as there are male parts on the second wafer.

It is also possible that said first plates have female parts that are different from each other. In this case, said second plates may also include male parts different from each other.

The method according to the invention can therefore be used to produce a piece-by-piece assembly, that is to say for the manufacture of one component at a time, or an assembly using plates comprising several parts, that is to say for the manufacture of several components at the same time.

The male and female parts used in the method according to the invention, whether they are individualized or on plates, can typically be obtained by etching, for example by chemical etching, by deep reactive ionic etching DRIE or by laser etching. .

In addition, for example to obtain components of even more complex shapes, typically with more levels, it is possible to use as male and female parts in the method according to the invention multi-level parts previously obtained by the implementation of the method according to the invention.

A person skilled in the art can also adapt the method according to the invention to assemble more than two parts at one time. He can for example assemble a female part comprising two openings with two male parts at the same time, each of these male parts being inserted at least in part into a separate opening.

[0064] As a variant, it is also possible to envisage inserting several male parts in a single opening of a female part.

The method according to the invention has many advantages.

It allows the manufacture of components of complex shapes, typically multi-level.

It is simple to achieve in that it does not require a step of activating surfaces and in that the parts can be positioned simply and precisely, both radially and axially, without a step of alignment or of prior centering.

It makes it possible to obtain resistant components and is thus particularly advantageous for the production of timepieces subjected to high mechanical stresses such as the stinger and the anchor for example.

In particular, the cooperation of the counterbore 5 and the shoulder 7 allows control of the assembly, its reliability and its reproducibility. It also makes it possible to increase the contact surfaces between the two parts and the strength of the component resulting from their assembly.

Claims (12)

1. A method of manufacturing at least one component (3; 23) comprising the following steps: a) provide a female part (1; 21) comprising at least one opening (4; 24) and a counterbore (5; 25) bordering this opening (4; 24) and a male part (2; 22) ) comprising a shoulder (7; 27), b) introduce at least part of the male part (2; 22) into the opening (4; 24) so that the counterbore (5; 25) and the shoulder (7; 27) come into abutment one against the other to axially position the male (2; 22) and female (1; 21) parts with respect to each other, at least the part of the male part (2; 22) located opposite the 'opening (4; 24) and / or the part of the female part (1; 21) defining the opening (4; 24) being made of silicon optionally covered with silicon oxide, said parts leaving between them a space (8 ) free, c) subjecting all of said male (2; 22) and female (1; 21) parts to a heat treatment so that on the surface of at least one of said parts forms a layer of silicon oxide filling at least partially said free space (8), d) continuing step c) at least until said two parts (1, 2; 21, 22) join together to form said component (3; 23). 2. Method according to claim 1, characterized in that said heat treatment is carried out in an oven. 3. Method according to claim 1 or 2, characterized in that said heat treatment is carried out at a temperature between 800 ° C and 1300 ° C, preferably between 950 ° C and 1150 ° C. 4. Method according to one of the preceding claims, characterized in that the opening (4) is through. 5. Method according to claim 4, characterized in that said part of the male part (2) passes right through the opening (4). 6. Method according to one of the preceding claims, characterized in that the part of the male part (2) introduced into the opening (4) and the opening (4) are of cylindrical shape. 7. Method according to one of the preceding claims, characterized in that the shapes of the part of the male part (2; 22) introduced into the opening (4; 24) and of the opening (4; 24) are complementary. 8. Method according to one of the preceding claims, characterized in that, at the end of step d) said free space (8) formed between the part of the male part (2; 22) introduced into the opening. (4; 24) and the part of the female part (1; 21) defining the opening (4; 24) is completely filled with silicon oxide. 9. Method according to one of the preceding claims, characterized in that the minimum distance between the surfaces of said part of the male part (2) located in the opening (4) and part of the female part (1) defining the opening (4), when the male part (2) is centered in the opening (4), is between 1 and 20 µm, preferably between 2 and 8 µm. 10. Method according to one of the preceding claims, characterized in that said component (3; 23) is a horological component typically chosen from an anchor, a balance, an oscillator, a spiral spring, a wheel, a lever, a pivot. , a cam, these watch components possibly comprising one or more elastic or bistable elements. 11. Method according to one of the preceding claims, characterized in that - in step a) the female part (1) is integrated into a first plate comprising at least one other female part and the male part (2) is integrated into a second plate comprising at least one other male part; - in step b) the first and second plates are arranged so that at least part of each of the two male parts or of at least two of the male parts is introduced into the opening of a separate female part; - The first and second plates are subjected to a heat treatment so that each of the assemblies comprising a male part and a female part obtained at the end of step b) is subjected to steps c) and d). 12. Method according to one of the preceding claims, characterized in that step a) consists in etching a female part (1; 21) comprising at least one opening (4; 24) and a counterbore (5; 25) bordering this opening (4; 24) and a male part (2; 22) comprising a shoulder (7; 27), in a silicon wafer, typically by deep reactive ionic etching DRIE.