UHR COMPONENTS

Description

[0001] The present invention relates to a method for manufacturing a watch component made from a micromachinable material. It also relates to a watch component itself.

[0002] It is known to manufacture watch components from a micromachinable material such as silicon and using techniques derived from microelectronics, notably deep reactive ion etching (in English Deep Reactive Ion Etching DRIE). The manufacturing process generally includes the following steps: to obtain a plate made of micro-machinable material, for example silicon, to form the watch component by engraving through the entire thickness of the plate, to release the component by separating it from the rest of the plate.

[0003] The use of materials and manufacturing techniques from microelectronics offers very interesting possibilities, particularly in terms of precision. However, one challenge is releasing the component without damaging it. Generally, clips, or material bridges, are used between the watch component and the rest of the circuit board. These clips hold the component securely to the board throughout the manufacturing process, especially during post-etching treatments (heat treatment, coating application, etc.), while also facilitating the component's release at the end of the manufacturing process.

[0004] Document EP2145857 describes a manufacturing process for a watch component similar to that described above. Material bridges are etched and hold the component securely to the plate during the various stages of watch component manufacturing. To facilitate the component's release at the end of the manufacturing process, the material bridges have a tapered section at the end connected to the component. This creates a weak point that facilitates the breakage of the material bridges. At the end of the manufacturing process, the watch component is released from the plate by brittle rupture of the material at the attachment points, or material bridges, in response to appropriate mechanical stress.

[0005] The breakage of the material due to brittle rupture between the material bridge and the component is difficult to control.

[0006] Document WO2013 / 093108 describes a method for manufacturing a micromechanical part from a plate made of a micromachinable material, with fasteners formed between the part and the plate. These fasteners are locally weakened by thinning to create joints. These joints are designed to allow the component to be detached by a torsional force in the plane of the plate. This results in a break between the part and the plate that lacks precision. The location of the break cannot be precisely determined a priori. It will be located along the weakened fastener, without it being possible to know in advance whether it will be close to the part or the plate. This can be problematic from both a functional and aesthetic point of view. Furthermore, to release the part by torsion in the plane of the plate, space must be provided around the part to allow for relative movement of the plate and the part.This necessitates reducing the number of parts manufactured from a plate.

[0007] Document EP0732635A1 discloses the manufacture of escapement anchors in a silicon wafer.

[0008] The present invention improves the situation.

[0009] For this purpose, the invention relates to a watch component and a method for manufacturing such a watch component according to the claims.

[0010] The invention will be better understood with the aid of the following description of various embodiments of the manufacturing process for a watch component, a micromachinable material plate incorporating a watch component, and a watch component according to the invention, with reference to the accompanying drawings in which: THE figures 1A, 1B and 1Crepresent respectively a top view and a cross-sectional view (in the yz plane) of a fastener between a watch component and a micromachinable material plate, and a partial view of the watch component, the plate and the fastener, according to a first embodiment not forming part of the subject matter of the claims; the figure 2 represents a view of a material bridge between a watch component and a micro-machinable material plate, according to the prior art; the figure 3 represents a top view of a material bridge between a watch component and a micro-machinable material plate, in an embodiment analogous to that of Figures 1A and 1B ; there figure 4 represents a top view of a material bridge between a watch component and a micro-machinable material plate, according to a second embodiment forming part of the subject matter of the claims; the figure 5represents a top view of a material bridge between a watch component and a micro-machinable material plate, according to a variant of the second embodiment; the figure 6 represents an enlarged and partial view of a pre-detachment zone of a material bridge according to a variant of the second embodiment; the Figures 7A and 7B represent the break zones of a watch component according to the prior art and of a watch component according to the first embodiment, respectively; the figure 8 represents another illustrative example of a rupture surface obtained by implementing the process of the invention, the figure 9 represents a flowchart of the steps in the manufacturing process, according to a specific implementation method; the Figures 10A to 10F represent a detailed view of the pre-detachment area of ​​a fastener between a watch component and a micro-machinable material plate, according to a first embodiment ( Figures 10C and 10D), a second embodiment (10E and 10F) and according to another embodiment (10A and 10B).

[0011] With reference to the figure 9 The process of the invention mainly comprises four steps S1, S2, S3 and S4 intended to manufacture a watch component 1 from a micro-machinable material.

[0012] The term "micro-machinable material" refers to any material suitable for micro-machining. According to the Berner Illustrated Professional Dictionary of Watchmaking, micro-machining designates "All the techniques derived from microelectronics (chemical etching, photolithography, vapor deposition of thin films, etc.), combined with other techniques enabling the machining of a wide range of materials such as semiconductors, ceramics, metals, certain polymers, etc." The micromachinable material used in the embodiment examples described below is silicon. Other micromachinable materials could obviously be used instead, such as diamond, quartz, and ceramics.

[0013] Step S1 involves obtaining a micromachinable material plate 2, in this case a silicon wafer, similar to those used for manufacturing microelectronic components. The wafer has, for example, a thickness of 150 µm. Of course, other wafer thicknesses can be used.

[0014] Step S2 consists of forming a watch component 1 and one or more attachments 3 within the plate to secure the component 1 to the rest of the plate 2. The watch component 1 and its attachments 3 are produced simultaneously, respectively during substeps referenced S20 (“DRIE_1”) and S21 (“DRIE_2”), by photolithography followed by deep reactive ion etching. During these steps S20 and S21, areas around the component 1 and the attachments 3 are etched into the plate 2, here through its entire thickness. In other words, a pattern composed of through-holes is etched into the plate 2, the shapes of which are adapted to form the component 1 and its attachments 3.

[0015] Alternatively, to form the watch component, one could use a multi-layered plate, for example, an SOI plate made of two silicon layers sandwiching a SiO2 layer, where one of the silicon layers is used to form the component, and the other silicon layer serves as a substrate. In such a case, a "through-hole" refers to an opening that passes through the entire silicon layer in which the component is formed, and not an opening that passes through the entire SOI plate.

[0016] The role of the fasteners 3 is to hold the watch component 1 securely to the plate 2 during manufacturing and to allow the watch component 1 to be released, by breaking the fastener 3, at the end of the manufacturing process. The fasteners 3 are material bridges between the engraved watch component 1 and the rest of the plate 2. They can have various shapes.

[0017] By definition, the "length" of a fastener is the dimension of the fastener along a longitudinal direction connecting the midpoints of the two connecting ends of the fastener (respectively to the rest of plate 2 and to component 1), in the plane of plate 2 (that is, a plane parallel to the upper and lower surfaces of the plate, through which the plate extends). Similarly, the "width" is the dimension of the fastener along a direction perpendicular to the longitudinal direction. On the Figures 1A and 1B , the length of the attachment 3 corresponds to the dimension along the y axis and its width corresponds to the dimension along the x axis.

[0018] In the example of implementation illustrated by the Figures 1A and 1B, the width of the attachment 3 decreases continuously from its end of connection to the rest of the plate 2 to its end of connection to the watch component 1. However, other shapes of attachment 3 could be considered, in particular an attachment of constant width, possibly with a narrowing near the end of connection to the component.

[0019] On the figures 1A, 1B and 1C , the watch component 1 shown is a balance spring (only half of the balance spring, from the center to the edge, is shown on the Figures 1B and 1C). Obviously, the process of the invention applies to the manufacture of other watch components. The watch component can be an entity ready to be mounted in a movement (for example a hand, a spring, etc.) or a part intended to be assembled to one or more other parts (for example a balance spring to the balance staff, a wheel plate to its staff, an anchor to the anchor stem (or staff), a balance wheel to the balance staff, etc.) before assembly.

[0020] Step S3 consists of creating, for each attachment 3, along a desired break line of the attachment 3, a pre-detachment zone 4.

[0021] By "break line" we mean a line in the plane of the plate along which the rupture of the material is desired when the release of component 1 from the plate 2. The break line here comprises a straight segment extending in the direction of the width of the fastener 3 (i.e. in the x direction), and over the entire width of the fastener 3, at the end of the connection of the fastener 3 to the component 1. Other shapes of break line and other locations could obviously be considered (for example in the middle of the fastener, or at the end of the connection with the plate).

[0022] The pre-detachment zone 4 extends along the break line, at the connection end of the attachment 3 to the watch component 1, over the entire width of the attachment 3 (along the x direction on the Figure 1A ). The length of the pre-detachment zone 4, that is to say its dimension along the break line (i.e. along the x direction on the Figure 1A), is for example between 20 and 150 µm.

[0023] In the example implementation shown on the Figures 1A and 1B , to create the pre-detachment zone 4, an opening 5 is engraved which extends continuously along the entire rupture line and thus crosses the fastener 3 in its width direction. The opening 5 has the shape of a trench extending in the x direction and having a right U-shaped cross-section ( figure 1B ).

[0024] The depth of trench 5 is, for example, approximately 75% of the total thickness of the plate (or component), and its width (i.e., its dimension along the y-direction) is, for example, on the order of 4 µm. The depth and width of trench 5 could obviously have other values. For example, the depth could be greater than or equal to half the thickness of the plate (or component) and less than or equal to 90% of the plate (or component) thickness, preferably less than or equal to 60% of said thickness. The width could be greater than or equal to 1 µm and less than or equal to 10 µm, preferably less than 5 µm.

[0025] The engraving of the watch component 1 (“DRIE_1”) and the engraving of the opening 5 (“DRIE_3”) of the pre-detachment area 4 can be carried out simultaneously by deep reactive ion etching (DRIE).

[0026] The opening 5 allows the creation in the fastener 3, at the end of the connection of the fastener 3 to the component 1, of a zone of lower mechanical resistance (i.e. the pre-detachment zone 4) and to initiate the break at the desired location on the component 1.

[0027] Step S4 consists of freeing the watch component 1 from the plate 2 by breaking or snapping the clips 3 along their break line. Breakage can be caused by applying a mechanical force to the clip 3 in a direction perpendicular, or substantially perpendicular, to the plane of the plate (corresponding to the z-direction on the Figures 1A and 1BBy "approximately perpendicular," we mean a direction at an angle of plus or minus 10° to the direction perpendicular to the plate (or perpendicular to the plane of the plate). Alternatively, failure is induced by applying a mechanical force to the fastener 3 in a direction at an angle of 45° or less to a direction perpendicular to the plate, and in particular 30° or less to a direction perpendicular to the plate. Since the material of the plate 1 is brittle and has no plastic deformation range, the force applied perpendicularly, or approximately perpendicularly, or in a direction close to the perpendicular to the plate, causes the material to break at the pre-detachment zone 4, along the line of failure. Failure is facilitated and controlled by the pre-detachment zone 4.One could also consider releasing component 1 from plate 2 by completing the engraving of the attachment at the pre-detachment area 4 with a laser treatment, in particular with femtosecond pulsed laser equipment.

[0028] Failure by mechanical stress in a direction perpendicular to the plate plane, in other words, by tension or torsion along the z-axis, is simple to implement and advantageous for manufacturing components, particularly spirals or wheels. Conversely, failure by mechanical stress within a plane of the plate, in other words, by torsion along a direction contained in the xy-plane, for example, by stressing a joint, would be impractical. Indeed, this would require space around the component to allow for the movement of its elements, space which could then be used for manufacturing other components.

[0029] The released watch component 1 has, on its edge, a fracture surface 100, as shown as an illustrative example on the figure 7B This surface 100 comprises two distinct adjacent parts, one 102 engraved and the other 101 broken. Part 102 corresponds to one of the U-shaped lateral walls of the engraved opening 5, while part 101 corresponds to the bottom of the broken U. On the figure 7A For comparison purposes, a fracture surface 100' obtained with a prior art attachment, without a pre-detachment zone 4, is shown. It can be seen that the fracture surface 100 of the figure 7B is sharper, cleaner and less extensive than the 100' rupture surface.

[0030] Various forms of implementation for the pre-detachment zone 4 can be considered. On the figures 3, 4 and 5Three distinct implementation examples have been schematically represented. For clarity, analogous or corresponding elements shown in the different figures bear the same references.

[0031] On the figure 3 The pre-detachment zone 4 includes an opening 5 in the form of a trench extending from the connection end of the fastener 3 to component 1, across the entire width of the fastener 3, along a straight break line. This is an embodiment analogous to that of the Figures 1A and 1B .

[0032] On the Figures 4 and 5 The pre-detachment zone 4 comprises a plurality of engraved openings 5 ​​aligned along the break line (this is not shown for clarity, but is analogous to that of the figure 3) and separated by unengraved bridges. The bridges and the openings 5 ​​are here the same length. They could obviously be of different lengths. The openings 5 ​​are parallelepiped-shaped. They can be blind, that is, engraved in part of the plate's thickness, or through, that is, engraved through the entire thickness of the plate. The forms of realization of the Figures 4 and 5 differ in the dimensions of the openings 5. On the figure 4 The openings 5 ​​have a width (along the y direction) of 2 µm and a length (along the x direction) of 10 µm. On the figure 5 The openings 5 ​​have a width (along the y-direction) of 2 µm and a length (along the x-direction) of 2 µm. Of course, the dimensions and shapes of the openings 5 ​​could be different. The dimensions of the openings 5 ​​aligned along the break line could, for example, be as follows: length (along the break line) between 2 µm and 10 µm; width between 1 µm and 5 µm; depth greater than or equal to half the thickness of the plate.

[0033] On the figure 8 As an illustrative example, a rupture zone 100 obtained with a pre-detachment zone 4 comprising a plurality of openings 5 ​​aligned along a rupture line and having the following characteristics: width of the attachment 3 at the bonding end to component 1 of 100µm, width of the pre-detachment openings 5 ​​of 4 µm; length of the pre-detachment openings 5 ​​of 2 µm; inter-opening space of 2 µm; depth of the openings 5 ​​equal to about 80% of the total thickness of the plate.

[0034] In this case, the fracture zone 100 comprises a fractured portion 101 (i.e., a fracture surface obtained by breaking the material) and a portion 102 having an alternating succession of engraved grooves and fractured grooves, arranged vertically. The two portions 101 and 102 are arranged one below the other according to the thickness of component 1. Note that on the figure 8 , the boundary between the broken part 101 and the grooved part 102 is curved because the engraving speed is not equal over the entire length of the break line, the areas near the ends of this break line being attacked faster than in the center.

[0035] In the preceding description, the watch component 1 and the aperture(s) 5 are engraved simultaneously. Alternatively, the engraving of the aperture(s) 5 and that of the watch component 1 can be carried out separately. In this case, the aperture(s) can be created using various ablation techniques, for example, DRIE etching, ablation using femtosecond pulses from laser equipment, mechanical ablation (diamond saw), or other methods. Preferably, the watch component 1 and the aperture(s) 5 are engraved simultaneously.

[0036] To separately etch the watch component 1 and the opening(s) 5 of the pre-detachment area, two masking steps can be used. In this case, a first masking step is performed to etch the opening(s) 5 of the pre-detachment area 4. A second masking step is then performed to etch the watch component 1 and its attachments 3, while protecting the opening(s) 5. Alternatively, the reverse could be considered: first, masking to etch the through-holes that form the watch component 1 and its attachments 3, then a second masking to etch the pre-detachment opening(s) 5 while protecting the through-holes. The masking can be mechanical or photolithographic using a photosensitive resin.

[0037] In the case of simultaneous engraving of the watch component 1 and the pre-cut opening(s) 5, the depth of the opening(s) 5 depends on various parameters related to the engraving of the watch component, including the attack speed of the DRIE engraving device and the duration of the engraving. Furthermore, the depth of the opening(s) 5 also depends on its width and length. In any event, in this case, the engraving time is the same for simultaneously creating both the openings intended to form the component and the pre-cut opening(s) 5.It is therefore preferable that the width of the pre-detachment openings 5 ​​be less than the width of the through-holes forming the watch component, or, if the through-holes forming the watch component have different widths, less than the smallest of the widths of the through-holes forming the watch component. In particular, if the width of the through-holes forming the component is greater than 40 µm, and / or is within a range of values ​​between 40 µm and 100 µm, or is greater than 100 µm, the width of the pre-detachment openings 5 ​​will advantageously be between 1 and 10 µm, or even between 1 and 5 µm.Thus, when the through-holes used to form the watch component and the pre-detachment hole(s) are made simultaneously, the width chosen for the pre-detachment hole(s) 5 according to the invention ultimately depends on the smaller of the widths of the through-holes forming the watch component and the desired depth for the pre-detachment hole(s). Furthermore, the width of the pre-detachment hole(s) may depend on specific characteristics of the DRIE engraving process and / or equipment used. Those skilled in the art will be able to perform the necessary adjustment tests to determine the optimal width of the pre-detachment holes 5.

[0038] The process may also include additional processing steps, carried out before or after component release, such as pre-thinning of the micro-machinable material wafer (to reduce its thickness), coating deposition, oxidation heat treatment, cleaning / degreasing, etc.

[0039] We will now describe different forms or variations of the pre-detachment zone implementation with reference to Figures 10A to 10F In these figures, the break line along which the pre-detachment zone extends is marked "L".

[0040] In the case of a pre-detachment zone with a continuous opening 5, of the type shown on the Figures 1A and 1B A pre-detachment opening 5 of variable width could be engraved along the break line. In this case, the depth of the opening along the break line, denoted L, can also be varied, as shown in the diagrams. Figures 10A and 10B , which respectively represent a top view of a fastener 3 between the plate 2 and the component 1 and a zoomed cross-sectional view in the plane defined by the x and z axes, of the pre-detachment opening 5.

[0041] For comparison, the Figures 10C and 10D represent respectively a top view of a fastener 3 between the plate 2 and the component 1 and a zoomed cross-sectional view in the plane defined by the x and z axes of the pre-detachment opening 5, conforming to the first embodiment in which the width and depth of the pre-detachment opening 5 are constant along the break line L.

[0042] THE Figures 10E and 10Frepresent respectively a top view of a fastener 3 between the plate 2 and the component 1 and a zoomed cross-sectional view in the plane defined by the x and z axes, of the pre-detachment opening 5, conforming to the second embodiment in which the pre-detachment area comprises a plurality of openings aligned along the break line L.

[0043] The presence of a break line is advantageous because it allows for the precise determination of the location and extent of the fracture surface. This is not the case when using a prior art technique, such as a simple material bridge or a material bridge of lesser width and / or thickness. In this case, the location of the fracture is not precisely determined. It could be somewhere along the weakened material bridge, and could be close to the component or to the rest of the plate. This results in uncertainty regarding the fracture location. Moreover, in some cases, the fracture degrades the aesthetic appearance of the component, or even its operational efficiency, which is particularly problematic.

[0044] The invention also relates to a watch component having a partially engraved fracture zone. The term "fracture zone" refers to the portion of the component's edge (across its entire thickness) containing one or more fracture surfaces. Depending on the embodiment of the component's manufacturing process, the fracture zone may include: a fully engraved part and a fully broken part arranged one above the other (depending on the thickness of the component); a part having an alternating succession of engraved grooves and broken grooves, and a fully broken part, arranged one above the other (depending on the thickness of the component); an alternating succession of engraved grooves and broken grooves (over the entire thickness of the component). Attachments 3, then a second masking to etch the pre-detachment opening(s) 5 while protecting the through-holes. The masking can consist of mechanical masking or masking achieved by photolithography of a photosensitive resin.

[0045] In the case of simultaneous engraving of the watch component 1 and the pre-cut opening(s) 5, the depth of the opening(s) 5 depends on various parameters related to the engraving of the watch component, including the attack speed of the DRIE engraving device and the duration of the engraving. Furthermore, the depth of the opening(s) 5 also depends on its width and length. In any event, in this case, the engraving time is the same for simultaneously creating both the openings intended to form the component and the pre-cut opening(s) 5.It is therefore preferable that the width of the pre-detachment openings 5 ​​be less than the width of the through-holes forming the watch component, or, if the through-holes forming the watch component have different widths, less than the smallest of the widths of the through-holes forming the watch component. In particular, if the width of the through-holes forming the component is greater than 40 µm, and / or is within a range of values ​​between 40 µm and 100 µm, or is greater than 100 µm, the width of the pre-detachment openings 5 ​​will advantageously be between 1 and 10 µm, or even between 1 and 5 µm.Thus, when the through-holes intended to form the watch component and the pre-detachment hole(s) are made simultaneously, the width chosen for the pre-detachment hole(s) 5 according to the invention ultimately depends on the smaller of the widths of the through-holes forming the watch component and the desired depth for the pre-detachment hole(s). Furthermore, the width of the pre-detachment hole(s) may depend on specific characteristics of the DRIE engraving process and / or equipment used. Those skilled in the art will be able to perform the necessary adjustment tests to determine the optimal width of the pre-detachment holes 5.

[0046] The process may also include additional processing steps, carried out before or after component release, such as pre-thinning of the micro-machinable material wafer (to reduce its thickness), coating deposition, oxidation heat treatment, cleaning / degreasing, etc.

[0047] We will now describe different forms or variations of the pre-detachment zone implementation with reference to Figures 10A to 10F In these figures, the break line along which the pre-detachment zone extends is marked "L".

[0048] In the case of a pre-detachment zone with a continuous opening 5, of the type shown on the Figures 1A and 1B A pre-detachment opening 5 of variable width could be engraved along the break line. In this case, the depth of the opening along the break line, denoted L, can also be varied, as shown in the diagrams. Figures 10A and 10B , which respectively represent a top view of a fastener 3 between the plate 2 and the component 1 and a zoomed cross-sectional view in the plane defined by the x and z axes, of the pre-detachment opening 5.

[0049] For comparison, the Figures 10C and 10D represent respectively a top view of a fastener 3 between the plate 2 and the component 1 and a zoomed cross-sectional view in the plane defined by the x and z axes of the pre-detachment opening 5, conforming to the first embodiment in which the width and depth of the pre-detachment opening 5 are constant along the break line L.

[0050] THE Figures 10E and 10Frepresent respectively a top view of a fastener 3 between the plate 2 and the component 1 and a zoomed cross-sectional view in the plane defined by the x and z axes, of the pre-detachment opening 5, conforming to the second embodiment in which the pre-detachment area comprises a plurality of openings aligned along the break line L.

[0051] The presence of a break line is advantageous because it allows for the precise determination of the location and extent of the fracture surface. This is not the case when using a prior art technique, such as a simple material bridge or a material bridge of lesser width and / or thickness. In this case, the location of the fracture is not precisely determined. It could be somewhere along the weakened material bridge, and could be close to the component or to the rest of the plate. This results in uncertainty regarding the fracture location. Moreover, in some cases, the fracture degrades the aesthetic appearance of the component, or even its operational efficiency, which is particularly problematic.

[0052] The invention also relates to a watch component having a partially engraved fracture zone. The term "fracture zone" refers to the portion of the component's edge (across its entire thickness) containing one or more fracture surfaces. Depending on the embodiment of the component's manufacturing process, the fracture zone may include: a fully engraved part and a fully broken part arranged one above the other (depending on the thickness of the component); a part having an alternating succession of engraved grooves and broken grooves, and a fully broken part, arranged one above the other (depending on the thickness of the component); an alternating succession of engraved grooves and broken grooves (over the entire thickness of the component).

Claims

1. A horology component (1) made of a micromachinable material comprising a partially etched fracture zone (4), characterized in that said fracture zone (4) comprises a part comprising an alternating succession of etched grooves and fractured grooves, and an entirely fractured part, which are arranged one above the other, or in that said fracture zone (4) comprises an alternating succession of etched grooves and of fractured grooves over the entire thickness of the component.

2. A horology component (1) made of a micromachinable material as claimed in the preceding claim, characterized in that said fracture zone (4) extends along a fracture line (L).

3. A horology component (1) made of a micromachinable material as claimed in the preceding claim, characterized in that said fracture zone (4) extends along the entirety of the fracture line (L).

4. A horology component (1) made of a micromachinable material as claimed in claim 2 or 3, characterized in that said fracture zone (4) comprises an etched part whose depth is less than or equal to 90% of the thickness of the horology component (1), preferably less than or equal to 60% of said thickness, and greater than or equal to half the thickness of the horology component (1).

5. A horology component (1) made of a micromachinable material as claimed in one of previous claims, characterized in that the material of the horology component (1) is a brittle material, notably one of the materials from the group containing silicon, diamond, quartz and ceramic.

6. A horology component (1) made of a micromachinable material as claimed in one of previous claims, characterized in that it is one of the elements from the group comprising a balance spring, a wheel, a hand, a spring, a pallet and a balance-wheel.

7. A horology component (1) made of a micromachinable material as claimed in one of previous claims, characterized in that it is made from a sheet of micromachinable material comprising said horology component (1) and at least one attachment (3) tethering the horology component (1) to the rest of the sheet (2), these being formed by openings etched into the thickness of the sheet (2), and in that the sheet (2) comprises a zone (4) for predetachment of the horology component (1) comprising, along a line (L) of desired fracture of the attachment (3), at least one opening (5) etched into the thickness of the sheet (2).

8. A horology component (1) made of a micromachinable material as claimed in the preceding claim, characterized in that the depth of the at least one opening (5) is less than or equal to 90% of the thickness of the sheet (2), preferably less than or equal to 60% of said thickness, and greater than or equal to half the thickness of the sheet (2).

9. A method for manufacturing a horology component (1) made of a micromachinable material, comprising the following steps: - procuring (S1) a sheet (2) of a micromachinable material; - forming (S2) the horology component (1) with at least one attachment (3) tethering it to the rest of the sheet (2), by etching the sheet (2); - creating (S3), along a line (L) of desired fracture of the attachment, a predetachment zone (4) comprising at least one opening (5) obtained by etching into the thickness of the sheet (2) ; - freeing (S4) the horology component (1) from the sheet (2), by fracturing the attachment (3) along the fracture line (L).

10. A method for manufacturing a horology component (1) made of a micromachinable material as claimed in the preceding claim, characterized in that the depth of the at least one opening (5) is less than or equal to 90% of the thickness of the sheet (2), preferably less than or equal to 60% of said thickness, and greater than or equal to half the thickness of the sheet (2).

11. A method for manufacturing a horology component (1) made of a micromachinable material as claimed in claim 9 or 10, characterized in that the step of forming (S2) the horology component (1) with at least one attachment (3) tethering it to the rest of the sheet (2) is performed using deep reactive ion etching, and in that the step of creating (S3), along a line (L) of desired fracture of the attachment, a predetachment zone (4), is performed using femtosecond laser micromachining.