• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Spiral spring (100) capable of being mechanically coupled to a balance, comprising at least one blade (102) wound in the form of a spiral, the blade (102) being made of at least one of the following materials: aluminate garnet rare earth, alexandrite, langasite, langatate, spinel, sapphire, fluorite, YLF, and in which the blade (102) has a height h between 100 µm and 150 µm, a width e between 30 µm and 50 µm, and a spacing p between two adjacent turns of the spiral spring (100) between 150 μm and 250 μm.
    公开号:CH712929B1
    申请号:CH00076/18
    申请日:2016-07-22
    公开日:2020-09-15
    发明作者:Aubert Jean-Jacques；Salvetat Thierry；Rey Alain-Marcel；Rey Philippe
    申请人:Commissariat Energie Atomique；Arnano；
    IPC主号:
    专利说明:

    Technical field and prior art
    The invention relates to the field of watchmaking, and more particularly a spiral spring, or hairspring, intended to be mechanically coupled to a balance, also called a spiral balance, to form a mechanical oscillator corresponding to the regulator member of 'a clockwork movement.
    Precision components for the watch industry, including the spiral spring, are generally made from special non-magnetic metal alloys with a low coefficient of expansion or compensated for thermal variation by a particular design.
    [0003] These components can also be made from micro-machined silicon by deep reactive ion etching, or DRIE ("Deep Reactive Ion Etching"). Such etching makes it possible to machine the silicon in three dimensions with a precision of the order of a thousandth of a millimeter. The parts produced in this way therefore all have exactly the same qualities with respect to each other, whether in terms of shape or weight. They also have perfectly smooth surfaces. Rigorously identical high-precision components are thus obtained, which makes it possible in particular to increase the performance of the movement produced with these components.
    [0004] Silicon is an interesting material for the production of precision watch components because it has a low coefficient of thermal expansion (of the order of 2.6.10 <-6> K <-1>), just like Invar®, widely used in watchmaking.
    Among the precision components of watchmaking, one of the most important is the regulator of mechanical watches corresponding to a mechanical oscillator composed of a flywheel, called a balance, and a spring in spiral shape, called a spiral or spiral spring, one end of which is fixed to the axis of the balance and the other end of which is fixed to a bridge, called a cock, in which the axis of the balance pivots.
    [0006] In operation, the balance oscillates around its equilibrium position (or neutral point). When the balance leaves this position, it arms the spiral spring. This creates a return torque which, when the balance is released, causes it to return to its equilibrium position. As the balance has acquired a certain speed, therefore a certain kinetic energy, it goes beyond its neutral point until the opposite torque of the spiral spring stops it and forces it to turn in the other direction. Thus, the spiral spring regulates the period of oscillation of the balance around its axis.
    [0007] The spiral spring fitted to mechanical watch movements is for example formed of an elastic metal blade of rectangular section wound on itself forming an Archimedean spiral and comprising between 11 and 15 turns, or turns. The spiral spring is mainly characterized by its return torque, the value of which depends on the Young's modulus of the blade material, the thickness of the spiral spring, the width of the spiral spring, the length of the spiral spring, and the angle of twist.
    The return constant or rigidity of a spiral spring, which characterizes the return torque per unit of torsion angle, must be as stable as possible, regardless of the temperature and the magnetic field at which the spiral spring is submitted.
    In order to improve the quality of this component, it would be advantageous for it to have an operating temperature range of between approximately 10 ° C and 50 ° C, and for the Young's modulus of the material used to be greater at about 200 GPa, for example between 200 and 250 GPa. However, silicon has a Young's modulus of the order of 170 GPa.
    [0010] In addition, the material used must be available in the form of a plate for the collective manufacture of these components, and especially machinable by microtechnology methods such as those from microelectronics.
    [0011] The glasses and glass-ceramics, for example of the ZERODUR® or PYREX® type, exhibit low thermal expansions (0.05.10 <-6> K <-1> for ZERODUR®) but have too low Young's moduli (ZERODUR ®: 91 GPa, PYREX®: 64 GPa).
    [0012] Silicon carbide exhibits a low coefficient of thermal expansion (4.10 <-6> K <-1>). However, its Young's modulus is too high for the horological application (450 GPa) and above all the stability of the Young's modulus with temperature is poor (4.10 <-5>).
    Disclosure of the invention
    An object of the present invention is to provide a spiral spring made from a material which is non-magnetic or weakly magnetic, that is to say comprising no or few magnetic ions, of which the modulus of Young is greater than approximately 200 GPa, which is very thermally stable, and which is compatible with collective manufacture and reproducible by the implementation of micro-technological methods.
    For this, the invention provides a spiral spring capable of being mechanically coupled to a balance, comprising at least one blade wound in the form of a spiral, the blade being made of at least one of the following materials: garnet rare earth aluminate, alexandrite, langasite, langatate, spinel, sapphire, fluorite, YLF.
    These materials used above for the realization of the spiral spring are rigid, that is to say have a Young's modulus greater than 200 GPa, do not contain magnetic ions, are durable over time, are very thermally stable and are compatible with collective manufacturing and reproducible by the implementation of micro-technological methods. These materials are therefore perfectly suited to the production of spiral springs having the desired characteristics.
    In addition, according to the invention, the blade has a height h between 100 μm and 150 μm, a width e between 30 μm and 50 μm, and a spacing p between two adjacent turns of the spiral spring between 150 µm and 250 µm.
    [0017] Such dimensions are optimal for obtaining the desired return torque of the spiral spring made with at least one of the materials indicated above, this return torque being very stable, whatever the temperature and the magnetic field at which the spiral spring is subjected. By making the blade with one or more of the hard materials mentioned above and with these dimensions, the operating temperature range of the spiral spring 100 can be between about 10 and 50 ° C, the torque of the spiral spring 100 can be obtained. being equal to approximately 2.10 <-4> N.mm, and the use of such a spiral spring 100 in a clockwork movement makes it possible to obtain a precision of between approximately -4 and +6 seconds / 24h.
    [0018] Advantageously, the blade can comprise YAG (Yttrium Aluminum Garnet, of formula Y3Al5O12). Indeed, this material is a crystalline material available industrially, combining both excellent chemical stability (identical to sapphire), a high Young's modulus (310 GPa), moderate thermal expansion (6.9.10 <-6> K <-1>) and a high thermal stability of the Young's modulus (-1,8.10 <-5>) to be compared to silicon (-5,2.10 <-5>) or to silicon carbide (4.10 <-5>) ).
    [0019] The invention also relates to a mechanical oscillator comprising at least one balance forming a flywheel mechanically coupled to at least one such spiral spring.
    [0020] The invention also relates to a clockwork movement comprising at least one such mechanical oscillator.
    The invention also relates to a method of producing a spiral spring capable of being mechanically coupled to a balance, comprising the production of at least one blade wound in the form of a spiral from at least one of the following materials: rare earth aluminate garnet, alexandrite, langasite, langatate, spinel, sapphire, fluorite, YLF.
    The realization of the blade may include at least the implementation of the following steps:<tb> <SEP> • production, on a layer of said at least one of the materials, of a first hard metallic and / or semiconductor mask, the first hard mask being crossed by at least a first opening opening onto the layer of material and corresponding to a pattern of the spiral spring, including direct bonding;<tb> <SEP> • etching of at least a portion of the layer of material intended to form the blade, at the level of the first opening, by the implementation of at least one ionic etching, and / or by the implementation of at least one ion implantation in the portion of the layer of material and of at least one chemical etching of the portion of the layer of material having undergone the ion implantation.
    This method therefore uses a first hard metal mask and / or semiconductor which, unlike a resin mask, can be made with a significant thickness, for example greater than about 10 microns or about 50 microns or even greater than about 100 µm or 200 µm. By making such a first hard mask, it is therefore possible to etch the layer of hard material serving to form the leaf of the spiral spring via the implementation of ion etching and / or ion implantation coupled with chemical etching. .
    [0024] This method also makes it possible to etch these hard materials by not requiring chemical reagents to form volatile compounds with its elements because the etching carried out is not a reactive etching such as an RIE etching or DRIE. Indeed, the etching of these materials is difficult to achieve with conventional etching techniques. Thus, the implementation of a reactive ionic etching, or RIE („Reactive Ion Etching“ in English) is not compatible with all these hard materials because such an etching uses chemical reagents which must form volatile compounds. with all the elements of these materials. For example, YAG cannot be etched by RIE etching in an industrial manner because there is no industrially available chemical reagent which can form volatile compounds with all the chemical elements of YAG. A purely ionic etching where abrasion is directly obtained by ion bombardment of the material is also not suitable for etching these hard materials because this etching is not selective and etches the material at approximately the same speed as the resins used. for material masking, or even less quickly. However, to produce the leaf of a spiral spring, the thickness of resin necessary to carry out the engraving of such a part is impossible to achieve (a resin can be deposited to a thickness of a few tens of microns at most). In addition, a resin will be rapidly deteriorated by the heating generated by the ion bombardment.
    Ion etching can be implemented in an ICP ("Inductively Coupled Plasma") system, or plasma torch system. In such a system, taking into account the materials present during the implementation of this process, they do not generate volatile compounds. This etching, which is analogous to an implementation of an ICP-RIE type etching, is however not reactive and only mechanical machining of the layer of material is obtained.
    In addition, the dimensions of the spiral spring mentioned above can be obtained by implementing the method described above carrying out a direct bonding of the first hard metal mask and / or semiconductor, then the non-reactive ion etching and / or ion implantation followed by chemical etching.
    [0027] Direct bonding, also called "molecular bonding" or "molecular bonding", or also called "wafer bonding" or "direct bonding" in English, is an assembly technique for joining two surfaces together via a setting. in direct contact with these two surfaces without using a bonding material (glue, wax, etc.). In this type of bonding, adhesion is obtained thanks to the fact that the surfaces to be bonded are sufficiently smooth (typically with a roughness of the order of 0.5 nm), free of particles or contamination, and sufficiently close together. from each other to initiate intimate contact between surfaces. In this case, the attractive forces between the two surfaces are high enough to cause molecular adhesion of the two surfaces to each other. Molecular bonding is induced by all the attractive forces of electronic interaction between the atoms or molecules of the two surfaces to be bonded (Van der Waals forces). In this process, the direct bonding produced between the layer of material to be etched and the first hard mask makes it possible to give the first hard mask very good hold on the layer of material to be etched, in particular during the etching of the layer of material to be etched. . This direct bonding also makes it possible to ensure good thermal transfer between the first hard mask and the layer of material to be etched during the etching of the layer of material to be etched.
    The etching of the portion of the layer of material at the level of the first opening by the implementation of at least one ion implantation in the portion of the layer of material and at least one chemical etching of the portion of the layer of material having undergone ion implantation can be produced when the implanted material is chemically stable before implantation, that is to say corresponds to a material which does not etch correctly with the usual chemistries of microelectronics (HF, ammonia, H3PO4, H2O2, TMAH, regal water, HNO3, KOH, acetic acid, or a mixture of these products), that is to say with an etching speed less than about 10 nm / min or even less at about 1 nm / min in the presence of these compounds, and chemically reactive after this implantation, that is to say which will be etched correctly in the presence of these elements with an etching speed greater than about 10 nm / min or even greater than about 30 nm / min.
    When the portion of the layer of material is etched by at least one ionic etching, the thickness of the first hard mask may be at least equal to the product of the thickness of the portion of the layer of material multiplied by the ratio the rate of etching of the material of the first hard mask over the rate of etching of the material of said layer of material during ion etching. These etching rates can be determined empirically. Thus, this condition makes it possible to ensure the presence of the first hard mask on the layer of material to be etched throughout the etching.
    [0030] The method may further comprise the production of the first opening of the first hard mask which is implemented before or after the direct bonding of the first hard mask on the layer of material.
    In this case, the realization of the first opening of the first hard mask may include at least the implementation of the following steps:<tb> <SEP> • production of a second dielectric hard mask on a metal and / or semiconductor layer intended to form the first hard mask, the second hard mask being crossed by at least one second opening opening onto the layer metallic and / or semiconductor and corresponding to the pattern of the first opening;<tb> <SEP> • etching of part of the metallic and / or semiconductor layer at the level of the second opening, such that the etched part of the metallic and / or semiconductor layer forms the first opening.
    The realization of the second hard mask can include at least the implementation of the following steps:<tb> <SEP> • deposition of a dielectric layer on the metallic and / or semiconductor layer;<tb> <SEP> • etching of the dielectric layer according to the pattern of the second opening.
    The etching of the portion of the layer of material at the level of the first opening can be carried out by alternately implementing steps of ionic etching of parts of the portion of the layer of material and of chemical cleaning steps removing etching residues generated during ionic etching steps, and / or by alternately implementing ion implantation steps of parts of the portion of the layer of material and chemical etching steps of parts of the portion of the layer of material having undergone the ion implantation steps.
    [0034] The method may further comprise, after the etching of the portion of the layer of material, the implementation of a step of mechanical and / or chemical removal of the first hard mask.
    [0035] The method may further comprise, before the direct bonding of the first hard mask on the layer of material, the implementation of a direct bonding of the layer of material on a support.
    In this case, the materials of the first hard mask and of the support may be similar, and, when the etching of the portion of the layer of material is carried out through the entire thickness of the layer of material, the removal of the first hard mask can be obtained by the implementation of a chemical etching also etching the support and releasing the layer of material vis-à-vis the support.
    Brief description of the drawings
    The present invention will be better understood on reading the description of exemplary embodiments given purely as an indication and in no way limiting with reference to the accompanying drawings in which:<tb> <SEP> • Figure 1 shows a cross section of a leaf of a spiral spring, object of the present invention, according to a particular embodiment;<tb> <SEP> • Figure 2 shows a top view of a spiral spring, object of the present invention, according to a particular embodiment;<tb> <SEP> • FIG. 3 represents a mechanical oscillator, object of the present invention, according to a particular embodiment and comprising a balance and a spiral spring;<tb> <SEP> • Figures 4 to 10 represent the steps of a method for producing a spiral spring, object of the present invention, according to a particular embodiment.
    Identical, similar or equivalent parts of the various figures described below bear the same numerical references so as to facilitate the passage from one figure to another.
    The different parts shown in the figures are not necessarily on a uniform scale, to make the figures more readable.
    The different possibilities (variants and embodiments) must be understood as not being mutually exclusive and can be combined with one another.
    Detailed description of particular embodiments
    Figure 1 shows a cross section of the blade 102, also called bar, of a spiral spring 100 according to a particular embodiment. FIG. 2 represents a top view of the spiral spring 100.
    The blade 102 is made of at least one hard material which is non-magnetic or weakly magnetic, the Young's modulus of which is greater than approximately 170 GPa, which is very thermally stable, and which is compatible with collective and reproducible manufacture by implementing micro-technological methods. Thus, the blade 102 is made of one or more of the following hard materials: rare earth aluminate garnet (TR3Al5O12, with TR corresponding to the rare earth type element), alexandrite (BeAl2O4), langasite (La3GaSiO14), langatate (La3Ga5,5Ta0,5O14), spinel (MgAl2O4), sapphire, fluorinated material such as fluorite (CaF2) or YLF (LiYF4).
    The rare earth aluminate garnet can advantageously be YAG (Yttrium Aluminum Garnet of formula Y3Al5O12), the Young's modulus of which is equal to approximately 310 GPa.
    Examples of dimensions of the spiral spring 100 are given below, these dimensions can be optimized depending on the material chosen and the constraints of use (mechanical size, period of oscillation, moment of inertia of the balance, etc. .):<tb> <SEP> • thickness, or height, h of the blade 102, and therefore of the spiral spring 100, between approximately 100 µm and 150 µm;<tb> <SEP> • width e of the strip 102 between approximately 30 μm and 50 μm;<tb> <SEP> • spacing p between two adjacent turns of the spiral spring 100 between approximately 150 µm and 250 µm;<tb> <SEP> • number of turns, or turns, of the spiral spring 100 between approximately 10 and 20;<tb> <SEP> • total length of the blade 102 equal to approximately 100 mm;<tb> <SEP> • diameter D of the spiral spring 100 equal to approximately 10 mm;<tb> <SEP> • diameter d of the first turn equal to approximately 1 mm.
    By making the blade 102 with one or more of the hard materials mentioned above, the operating temperature range of the spiral spring 100 is between approximately 10 and 50 ° C. The torque of the spiral spring 100 that can be obtained is equal to approximately 2.10 <-4> N.mm. The use of such a spiral spring 100 in a clockwork movement makes it possible to obtain a precision of between approximately -4 and +6 seconds / 24h.
    Figure 3 shows a top view of a mechanical oscillator 200 comprising the spiral spring 100 and a balance 202, forming a flywheel, to which the spiral spring 100 is mechanically coupled through one of its ends 104. Another end 106 of the spiral spring 100 is fixed to the part in which the axis of the balance 202 pivots. The operation of this mechanical oscillator 200 is similar to that previously described in connection with the state of the art. .
    The realization of such a spiral spring 100 involves implementing a particular etching process. Indeed, the implementation of a reactive ionic etching, or RIE („Reactive Ion Etching“ in English) is not compatible with the hard materials mentioned above because such an etching calls for chemical reagents which must form volatile compounds with all the elements of these materials, and that it is not possible to produce a resin mask having a sufficient thickness for etching the spiral spring 100.
    An example of a method of making a spiral spring 100 from a layer 300 formed from one or more of the materials listed above is described below in conjunction with Figures 4 to 10.
    In the example described here, the material of the layer 300 is YAG. The layer 300 has a thickness (dimension along the Z axis shown in FIG. 4) of between approximately 100 μm and 150 μm.
    The lateral dimensions of the layer 300 (dimensions in the plane (X, Y)) may not correspond to the standard dimensions of substrates, or wafers, in the field of microelectronics. To perform the etching of the layer 300 with standard microelectronics equipment, the layer 300 is bonded to a support 302 corresponding here to a substrate of standard lateral dimensions, for example with a diameter equal to 300 mm (FIG. 4). This substrate is here composed of a semiconductor, for example of silicon. The bonding of the layer 300 on the support 302 also makes it possible to strengthen the mechanical retention of the layer 300 and to facilitate its handling because the support 302 can serve as a mechanical handle during handling.
    The bonding of the layer 300 on the support 302 is advantageously a direct bonding, which makes it possible to confer a very good hold on the layer 300 on the support 302 during the implementation of the following steps of the etching process, and also makes it possible to ensure good thermal transfer between the layer 300 and the support 302, in particular during the subsequent etching of the layer 300.
    Another metallic and / or semiconductor layer 304 is then bonded to the layer 300 (FIG. 5). The layer 304 will be used to produce a first hard mask 305 which will be used for the etching of the layer 300. In the embodiment described here, the layer 304 corresponds to a silicon substrate. When the layer 300 is intended to be etched by ionic etching, the thickness of the layer 304 is chosen as a function of the thickness of the layer 300 which is intended to be etched, as well as of the selectivity of etching by the ion beam. of the material of the layer 300 with respect to that of the layer 304. The thickness of the layer 304 is chosen to be greater than or equal to the thickness of the layer 300 multiplied by the ratio between the etching speed of the material of the layer 304 on the etching speed of the material of the layer 300 during the ionic etching. For example, in the case of a layer 300 of YAG with a thickness equal to approximately 100 μm, and of a layer 304 made of silicon, because the etching speed of silicon is approximately twice that of YAG during ion etching, the thickness of the layer 304 is chosen to be greater than or equal to approximately twice the thickness of the layer 300, ie greater than or equal to approximately 200 μm.
    It is possible that the layer 304 comprises nickel or chromium, and has a thickness between approximately 20 μm and 150 μm.
    The layer 304 is secured to the layer 300 via the implementation of a direct bonding between these two layers, which allows to give a very good retention of the layer 304 on the layer 300 during the implementation. of subsequent steps of the etching process, and also makes it possible to ensure good thermal transfer between the layers 304 and 300 during the subsequent steps of the method, in particular during the etching of the layer 300.
    Advantageously, between the layer 304 and the layer 300, it is possible to interpose at least one intermediate layer of oxide (comprising for example SiOx), nitride (comprising for example SiNx) or metal ( comprising for example copper, tungsten, Ti or TiN). This intermediate layer may have a thickness of between approximately 10 nm and 1 μm. This intermediate layer can be constrained. Such an intermediate layer makes it possible to promote direct bonding between the layers 300 and 304, and / or to absorb all or part of the stresses generated in the stack due to the difference in the coefficient of thermal expansion between the materials present, when steps inducing thermal budgets (in particular during the etching of the layer 300). This intermediate layer can be initially arranged on one of the faces of the layers 300 and 304 intended to be joined to one another, or else be obtained by forming, on each of the two faces of the layers 300 and 304 intended to be integral with one another, a part of this intermediate layer and which, once placed against each other, together form this intermediate layer.
    Annealing can then be carried out in order to increase the bonding energy between the layers 300 and 304. This annealing also makes it possible to increase the bonding energy between the layer 300 and the support 302. This annealing can be carried out under a di-nitrogen atmosphere, for example at a temperature of between approximately 100 ° C. and 300 ° C. depending on the materials present and more particularly on their difference in coefficient of thermal expansion.
    The layer 304 is then etched in order to form the first hard mask 305. This etching is intended to form one or more first openings in the layer 304, the pattern of which corresponds to that intended to be etched in the layer 300, c ' that is to say the pattern of the spiral spring (s) 100 intended to be produced in the layer 300. For this, a dielectric layer 306 intended to form a second hard mask 307 is deposited on the layer 304 (FIG. 6). In the example described here, because the layer 306 is deposited via a full plate deposit, parts of this layer 306 are also deposited on parts of the layer 300 not covered by the layer 304 as well as on parts of the support. 302 not covered by the layer 300. The dielectric material of the layer 306 is for example SiN or SiO2, and the thickness of the layer 306 is for example between approximately 3 μm and 5 μm.
    A resin mask 308 is then produced on the structure produced, and covers the parts of the layer 306 which are not intended to be etched. The mask 308 comprises one or more openings 310 formed by photolithography and etching, and the pattern of which corresponds to that of the second opening (s) 312 intended to be formed through the layer 306 (themselves having a pattern corresponding to that of the or the first openings of the first hard mask 305 intended to be produced from the layer 304). Etching of layer 306, for example plasma etching, is then carried out, forming the second opening (s) 312 through layer 306, and therefore forming second hard mask 307 (FIG. 7).
    The resin mask 308 is then removed, then the layer 304 is etched according to the pattern defined by the second hard mask 307, for example by deep plasma etching, forming the first opening (s) 314 through the layer 304 ( figure 8). The first hard mask 305 is thus obtained.
    The first hard mask 305 is then used to etch the layer 300 according to the pattern defined by the first opening (s) 314. The layer 300 can be etched by implementing an ionic etching, thus transferring the pattern of the one (s). first openings 314 in the layer 300. This ionic etching etches the layer 300 by forming one or more openings 316 which here pass through the entire thickness of the layer 300. This ionic etching also etches the other materials present, that is to say ie the second hard mask 307, the first hard mask 305 as well as the support 302, thus reducing the thickness of these elements. As described above, the thickness of the first hard mask 305 is sufficiently large so that at least part of the first hard mask 305 is still present on the layer 300 at the end of this ionic etching. In FIG. 9, it can be seen that part of the first hard mask 305 is still present on the layer 300 after the formation of the first opening (s) 316 through the layer 300. The support 302 also has a sufficient thickness so that it is not etched over its entire thickness during the implementation of this ionic etching. In Figure 9, the opening 316 formed through the layer 300 also extends through a portion of the thickness of the support 302.
    The ionic etching is for example implemented in an ICP type etching system (standing for “Inductively Coupled Plasma”) which is generally used to implement an ICP-RIE type etching (for example, an engraving equipment marketed by the company Corial® under the name Corial 210IL). The RF power of the engraving equipment used is for example equal to 400 W or 800 W. The ICP power of the engraving equipment used is for example equal to 800 W or 1600 W. Advantageously, for an engraving of YAG, the RF and ICP powers of the engraving equipment used are for example equal to approximately 800 W each. Given the materials present, the ICP etching used is not a reactive ionic etching because no volatile compound is generated by the implementation of this etching. The chemical composition of the gas used is for example the following: CHF3: 100 sccm; Cl2: 30 sccm; O2: 25 sccm. The unit sccm stands for "standard cubic centimeters per minute", or one cubic centimeter per minute under the following conditions: Temperature = 0 ° C (32 ° F) and Pressure = 101.325 kPa (14.6959 psia). The etching is carried out with a working pressure equal to approximately 5.7 mT (ie approximately 0.76 Pa), and with a cathode temperature equal to approximately 20 ° C.
    The etching equipment can be used by placing a liner in the vacuum etching chamber. The liner forms an enclosure, for example of cylindrical shape, within which the plasma is generated and the etching takes place. This liner can be dismantled in order to be able to have, during the implementation of another etching, a clean liner in the chamber. In fact, given that the etched materials do not form volatile compounds which can be removed by vacuum pumping, the etched materials are redeposited on the walls of the etching chamber, and therefore here on the liner. It is therefore possible, after the etching carried out, to remove the liner in order to clean it and / or replace it with another liner, which makes it possible in particular to obtain a significant saving in time compared to a long and difficult cleaning. 'an etching chamber which would not include this liner. The liner comprises a material, for example quartz, which can withstand the high temperatures generated by the etching.
    The table below indicates the etching speeds obtained, in μm / min, for different RF and ICP powers, and for different materials, by etching a spiral spring pattern. These values are measured between the coils of the spiral spring, except those indicated in brackets which are measured at the center of the spiral spring.<tb> RF power <SEP> 400 W <SEP> 400 W <SEP> 800 W <SEP> 800 W<tb> ICP power <SEP> 800 W <SEP> 1600 W <SEP> 800 W <SEP> 1600 W<tb> Quartz <SEP> 0.27 <SEP> 0.33 (0.61) <SEP> 0.46 (0.84) <SEP> 0.56<tb> Glass <SEP> 0.32 <SEP> - <SEP> 0.45 <SEP> 0.61<tb> LTO <SEP> 0.12 <SEP> - <SEP> - <SEP> 0.46<tb> YAG <SEP> 0.03 <SEP> 0.08 <SEP> 0.15 <SEP> -
    The measured etching speeds turn out to be relatively high. Regardless of the material engraved, these engraving speeds increase when the ICP and RF powers are greater. However, RF power plays a predominant role in increasing the rate of quartz etching. The quartz etching speed is slower in the areas between the arms of the spiral spring than in the open area in the center thereof. On the contrary, glass etching is more sensitive to the power of the ICP. The LTO etching speed under the highest power conditions is 0.46 µm / min which is compatible with the deep etching application. The etching speed of the YAG type optical crystal (up to 0.15 µm / min) is mainly determined by the RF power.
    Advantageously, the etching of the layer 300 is carried out by alternately implementing several ionic etching steps, each etching a part of the thickness of the layer 300, and several chemical cleaning steps removing etching residues generated during the ionic etching steps. At each new etching step, the part or parts of the layer 300 which are etched correspond to that (s) located directly above that (s) previously etched.
    The etching of the layer 300 can also be carried out by the implementation of an ion implantation of the material of the layer 300 through the first opening (s) 314 of the first hard mask 305, and of a chemical etching of the portion or portions of material having undergone ion implantation. This ion implantation makes it possible to make the material receiving the ion beam amorphous (for example formed of Ne <+> ions). The chemical etching implemented corresponds for example to a wet etching using a concentrated solution of H3PO4 and at high temperature (for example greater than about 80 ° C.).
    Given the large thickness of the material of the layer 300 which is intended to be etched, the etching of the layer 300 is advantageously carried out by alternately implementing several ion implantation steps, each carrying out an ion implantation in a part of the thickness of the layer 300, and several chemical etching steps of the parts of the portion of the layer of material implanted ionically. At each new ion implantation step, the part or parts of the layer 300 which are implanted lie directly above that (s) previously etched.
    Once the etching of the layer 300 is completed, the first hard mask 305 is removed mechanically, for example by implementing a mechanical-chemical planarization (CMP) step, and / or chemically by etching. When the openings 316 made through the layer 300 pass through the entire thickness of the layer 300 and the materials of the first hard mask 305 and the backing 302 are similar, as in the example described here where the first hard mask 305 and the support 302 are made of silicon, the removal of the first hard mask 305 is advantageously carried out by the implementation of a chemical etching, for example via a TMAH solution for etching the silicon, this etching also releasing the layer 300 and therefore the or the spiral springs 100, vis-à-vis the support 302 which is etched at its interface with the layer 300 (FIG. 10).
    The aperture or apertures 316 formed through the layer 300 thus define the contours of the elements produced by this etching process, corresponding here to elements of the spiral spring type 100.
    In the particular embodiment described above, the layer 304 is first of all secured to the layer 300 then the first hard mask 305 is made from this layer 304. As a variant, it is possible that the first hard mask 305 is glued to the layer 300 after having been produced, that is to say after the opening (s) 314 have been made in the layer 304. In this case, steps similar to those previously described in connection with Figures 6 to 8 are implemented prior to the bonding of the first hard mask 305 on the layer 300.
    In the particular embodiment described above, the layer 300 is etched over its entire thickness, the opening (s) 316 passing through the layer 300 from its upper face to its lower face. As a variant, the layer 300 can be etched through only part of its thickness, the openings 316 in this case only being formed through part of the thickness of the layer 300.
    权利要求:
    Claims (10)
    [1]
    1. Spiral spring (100) capable of being mechanically coupled to a balance, comprising at least one blade (102) wound in the form of a spiral, the blade (102) being made of at least one of the following materials: garnet d ' rare earth aluminate, alexandrite, langasite, langatate, spinel, sapphire, fluorite, YLF,in which the blade (102) has a height h between 100 µm and 150 µm, a width e between 30 µm and 50 µm, and a spacing p between two adjacent turns of the spiral spring (100) between 150 µm and 250 µm.
    [2]
    2. Spiral spring (100) according to claim 1, wherein the blade (102) comprises YAG.
    [3]
    3. Mechanical oscillator (200) comprising at least one balance (202) forming a flywheel mechanically coupled to at least one spiral spring (100) according to one of claims 1 and 2.
    [4]
    4. Timepiece movement comprising at least one mechanical oscillator (200) according to claim 3.
    [5]
    5. A method of making a spiral spring (100) capable of being mechanically coupled to a balance, comprising the production of at least one blade (102) wound in the form of a spiral from at least one of the materials. following: rare earth aluminate garnet, alexandrite, langasite, langatate, spinel, sapphire, fluorite, YLF, in which the blade (102) has a height h between 100 µm and 150 µm, a width e between 30 µm and 50 μm, and a spacing p between two adjacent turns of the spiral spring (100) of between 150 μm and 250 μm.
    [6]
    6. The method of claim 5, wherein the production of the blade (102) comprises at least the implementation of the following steps:• production, on a layer (300) of said at least one of the materials, of a first hard mask (305) metal and / or semiconductor, the first hard mask (305) being crossed by at least a first opening ( 314) opening onto the layer of material (300) and corresponding to a pattern of the spiral spring (100), including direct bonding;• etching of at least a portion of the layer of material (300) intended to form the blade (102), at the level of the first opening (314), by the implementation of at least one ionic etching in a system ICP, and / or by the implementation of at least one ion implantation in the portion of the material layer (300) and at least one chemical etching of the portion of the material layer (300) having undergone the ion implantation.
    [7]
    7. The method of claim 6, wherein, when the portion of the layer of material (300) is etched by at least one ionic etching, the thickness of the first hard mask (305) is at least equal to the product of the. thickness of the portion of the layer of material (300) multiplied by the ratio of the rate of etching of the material of the first hard mask (305) to the rate of etching of the material of said layer of material (300) during ion etching .
    [8]
    8. Method according to one of claims 6 and 7, further comprising the production of the first opening (314) of the first hard mask (305) which is implemented before or after the direct bonding of the first hard mask (305). on the material layer (300).
    [9]
    9. The method of claim 8, wherein the realization of the first opening (314) of the first hard mask (305) comprises at least the implementation of the following steps:• production of a second hard mask (307) dielectric on a metal and / or semiconductor layer (304) intended to form the first hard mask (305), the second hard mask (307) being crossed by at least one second opening (312) opening onto the metallic and / or semiconductor layer (304) and corresponding to the pattern of the first opening (314);• etching of part of the metallic and / or semiconductor layer (304) at the second opening (312) such that the etched part of the metallic and / or semiconductor layer (304) forms the first opening (314).
    [10]
    10. Method according to one of claims 6 to 9, further comprising, after the etching of the portion of the layer of material (300), the implementation of a step of mechanical and / or chemical removal of the first mask. hard (305) and further comprising, before the direct bonding of the first hard mask (305) on the layer of material (300), the implementation of a direct bonding of the layer of material (300) on a support ( 302), wherein the materials of the first hard mask (305) and the backing (302) are similar, and wherein when the etching of the portion of the layer of material (300) is performed through the entire thickness of the layer of material (300), the removal of the first hard mask (305) is obtained by the implementation of a chemical etching also etching the support (302) and releasing the layer of material (300) vis-à-vis of the support (302).
    类似技术:
    公开号 | 公开日 | 专利标题
    EP1519250B1|2010-06-30|Thermally compensated balance-hairspring resonator
    EP2104006B1|2010-07-14|Single-body double spiral and method for manufacturing same
    EP1346402B1|2008-10-01|Method for producing a stacked structure
    EP0660140A1|1995-06-28|Method for making a relief structure on a substrate from semiconductor material
    FR2842650A1|2004-01-23|Fabrication of substrates for optics, electronics, or optoelectronics, by implanting atomic species beneath front face of ingot to create zone of weakness, bonding support, and directly detaching portion of top layer bonded to support
    CH707630A2|2014-08-29|Temperature compensated type balance, timepiece movement, mechanical timepiece and method of manufacturing such a temperature compensation type balance.
    FR2574953A1|1986-06-20|MIRROR SUBSTRATE, IN PARTICULAR FOR PRECISION OPTICS, AND METHOD FOR MANUFACTURING THE SAME
    EP2572374B1|2019-10-02|Method for building a substrate holder
    EP2091861B1|2017-03-15|Fabrication of multilevel micromechanical silicon components
    EP2795411B1|2021-11-03|Method for manufacturing a resonator
    CH702431B1|2015-05-29|A method of manufacturing a micromechanical part.
    CH712929B1|2020-09-15|Spiral spring and method of producing the spiral spring.
    FR2866982A1|2005-09-02|Fabrication of electronic components using a noble support for front end fabrication and a less costly support, with specific desired physical properties, for back end fabrication
    EP2676288B1|2017-08-09|Method for producing a substrate holder
    WO2017016997A1|2017-02-02|Process for etching hard materials
    EP2777070B1|2016-07-20|Method for obtaining a heterogeneous substrate for the production of semiconductors, and corresponding substrate
    EP3497711A1|2019-06-19|Method for producing an epitaxial layer on a growth plate
    EP3822709A1|2021-05-19|Method for manufacturing a timepiece component
    FR2883370A1|2006-09-22|Star shaped mechanical resonator manufacturing method for gyrometer measurement device, involves corroding resonator arms` sides such that arms thickness reduction corresponds to lowering of frequency of flexion mode outside arms plane
    FR2939151A1|2010-06-04|INGOTS FORMS OF AT LEAST TWO BASIC INGOTS, A METHOD OF MANUFACTURE AND A PLATELET THEREFROM
    EP3907565A1|2021-11-10|Method for manufacturing a silicon timepiece component
    EP3865954A1|2021-08-18|Method for manufacturing a device with flexible single-piece silicon sheets, for timepieces
    CH703445B1|2012-01-31|Silicon micromechanical part e.g. toothed wheel, for movement of mechanical timepiece i.e. mechanical watch, has two secant surfaces connected with each other by junction, where junction is in form of round stop
    CH713854A2|2018-12-14|Method of manufacturing a micromechanical part
    CH717124A2|2021-08-16|A method of manufacturing a device with one-piece flexible silicon blades, in particular for watchmaking.
    同族专利:
    公开号 | 公开日
    FR3039292B1|2019-05-31|
    FR3039292A1|2017-01-27|
    WO2017017000A1|2017-02-02|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    CH702151A1|2009-11-10|2011-05-13|Cartier Creation Studio Sa|Pieces of method for producing micromechanical including glass ceramic.|
    CH704906B1|2011-05-09|2020-06-30|Lvmh Swiss Mft Sa C/O Zenith Succursale De Lvmh Swiss Mft Sa|Spiral spring in silicon for mechanical watch.|
    EP2685325B1|2012-07-11|2016-04-06|Diamaze Microtechnology S.A.|Spiral spring, method for producing the same, applications and micromechanical drives|
    CH709082B1|2013-12-20|2018-12-14|Rolex Sa|Method of manufacturing a watch component|
    WO2015106828A1|2014-01-20|2015-07-23|The Swatch Group Research And Development Ltd|Timepiece with at least one photoluminescent component|AT523288B1|2020-03-12|2021-07-15|Mb Microtec Ag|Watch component|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    FR1557061A|FR3039292B1|2015-07-24|2015-07-24|SPIRAL SPRING AND METHOD OF MAKING THE SPIRAL SPRING|
    PCT/EP2016/067495|WO2017017000A1|2015-07-24|2016-07-22|Spiral spring and method for producing the spiral spring|
    [返回顶部]