Metallization and support with metallization portion

Abstract

To provide a metallization portion having excellent durability or adhesive strength and a system including the metallization portion and a support.SOLUTION: A system (36) is provided that includes a support (3) and at least one metallization portion (6). A metallization portion (6) includes at least a first layer (1) and a second layer (2), the support (3) includes a support surface (7), the first layer (1) is arranged between the support surface and the second layer (2), the second layer (2) is made of at least 90 weight% of a noble metal, the first layer (1) is made of transition metals and / or metals and / or metalloids, the first layer (1) has an ultrasonic attenuation effect.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a metallization part including a first layer and a second layer, and a support (for example, oxide ceramics) including a metallization part having improved resistance.

Background Art

[0002] Oxide ceramics are used, for example, as insulators, substrates of printed circuit boards, or measurement elements, in various applications as a support (also known as a substrate).

[0003] In technical applications, the support often includes a metallization part. It is often provided to conduct electric charges. Thus, the metallization part can be provided in the form of conductor tracks, electrodes, or protection against electrostatic charging of an electrically insulated surface. For these purposes, the metallization part covers at least a partial area of the oxide ceramics surface.

[0004] Generally, oxide ceramics such as quartz, gallium phosphate, langasite are metallized using a layer structure of high melting point metals and noble metals. The high melting point metal layer functions as an adhesion promoting layer because it provides good adhesion to oxide ceramics due to its high oxygen affinity. On the other hand, the noble metal layer is used for good electrical conductivity and / or bondability of the layer.

[0005] The high melting point metal is understood to mean an element of Group 4 (titanium, zirconium, hafnium), Group 5 (vanadium, niobium, tantalum), or Group 6 (chromium, molybdenum, tungsten). For the purposes of the present application, the noble metal is understood to mean gold, platinum, iridium, palladium, osmium, ruthenium, rhodium, silver.

[0006] Bonding exists when a conductor (e.g., a bonding wire made of gold or aluminum) can achieve a material connection (also called a bond) between a layer and the conductor by means of a common bonding technique such as wire bonding (also known as ultrasonic bonding or thermosonic bonding).

[0007] For example, it is well known that materials with a high modulus of elasticity such as high melting point metals have poor damping characteristics against mechanical vibrations. Since ultrasonic waves used in wire bonding are well transmitted by the support, this is a drawback. The mechanical stress caused by the mechanical vibration due to ultrasonic waves often leads to peeling and / or cracking of the substrate (especially an oxide ceramic substrate), and as a result, the adhesive strength of the material connection part (also called bonding or joining in this specification) decreases. Cracking and / or peeling are generally called damage caused by vibration-induced mechanical stress (also known as mechanical load).

[0008] Ultrasonic waves are generally understood to mean sound or sound waves having a frequency in the range of 20 kHz to 1 GHz. Sound waves are mechanical vibrations.

[0009] In particular, when using an oxide ceramic having piezoelectric properties as a support for the measurement element of a transducer exposed to mechanical stress, peeling and / or cracking in the support near or at the position of the joint are not allowed. This is because mechanical stress (e.g., acceleration of the transducer) may lead to damage to the joint.

[0010] From Patent Document 1 and Patent Document 2, it is known that a piezoelectric measurement element often includes a metallization portion in the form of a conductive layer. Platinum may be used as a conductive layer for mechanically protecting a piezoelectric material that is generally brittle and often manufactured from single crystals. As a noble metal, platinum also has excellent chemical resistance to oxidation. However, as a drawback, during the bonding of the metallization portion by wire bonding, the piezoelectric crystal under the metallization portion may be damaged by ultrasonic-induced mechanical vibrations transmitted. Usually, since the metallization portion is not damaged, this cannot be directly seen through the metallization portion at first. However, since the connection between the metallization portion and the piezoelectric measurement element is damaged, the durability or adhesive strength of the bonding between the metallization portion and the conductor becomes insufficient.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0012] An object of the present invention is to provide a metallization portion for a support that reduces the above-mentioned drawbacks. Another object of the present invention is to reduce mechanical stress on the support by vibrations such as ultrasonic waves during wire bonding. Another object of the present invention is to provide a system including a metallization portion and a support that can be easily joined by wire bonding.

Means for Solving the Problems

[0013] This object is achieved by the configuration of the independent claims.

[0014] The present invention relates to a system including a support and at least one metallization part. The metallization part includes at least a first layer and a second layer. The support has a support surface. The first layer is disposed between the support surface and the second layer.

[0015] The layer, also called a coating, is attached to a support, also called a substrate or base material. It at least partially covers the surface of the support (simply put, the support surface). Thus, the layer has an extension along a first axis and an extension along a second axis, and the first axis and the second axis extend parallel to the support surface. Further, the layer has an extension along a third axis that extends perpendicular to the support surface, and this extension is called the layer thickness. The layer is optionally manufactured to uniformly cover the topography of the support surface. The layer thickness is determined by the X-ray fluorescence method in accordance with ISO 3497:2000 of the International Organization for Standardization.

[0016] The second layer is made of at least 90% by weight of a noble metal. This has the advantage of being resistant to corrosion and thus showing high chemical resistance. A noble metal is an element having a high positive standard potential, also known as the normal potential for a hydrogen electrode. Thus, for example, the standard potential of gold is 1.5 V (volts), and the standard potential of silver is 0.8 V. Also, due to the high proportion of noble metal in the second layer, it shows high conductivity and thus serves as an electrode for conducting charges and an electrode for bonding to an electrode for conducting charges.

[0017] The first layer is made of a transition metal and / or a metal and / or a metalloid. The phrase "and / or" should be understood as an inclusive disjunction. The first layer has an ultrasonic attenuation effect. This has the advantage that mechanical stress acting on the support due to vibrations such as, for example, ultrasonic waves is reduced. In this way, the mechanical stress acting on the substrate due to mechanical vibrations generated, for example, during wire bonding is advantageously reduced. In particular, when using a substrate made of oxide ceramics, the adhesive strength of the material bond between the conductor and the second layer after wire bonding increases.

[0018] In wire bonding, a first end of a conductor, also known as a bonding wire, is pressed against a second layer by a bonding tool. The bonding tool transmits ultrasonic vibrations to the conductor. As a result, a diffusion process occurs between the conductor and the second layer, forming a bond between the materials. However, the ultrasonic waves do not localize in the first layer but propagate through the first and second layers to the support. The mechanical stress acting on the support due to the mechanical vibrations induced by the ultrasonic waves is reduced by the second layer having an ultrasonic attenuation effect.

[0019] Other advantages and aspects of the present invention are disclosed in the examples.

[0020] Hereinafter, the present invention will be described in more detail with reference to the drawings and by way of examples.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

[0022] Throughout the figures, like reference numerals represent like items or components.

Modes for Carrying Out the Invention

[0023] Figure 1 shows a schematic cross-sectional view of one embodiment of system 36. The system 36 shown in Figure 1 includes a support 3 and a metallization portion 6. The metallization portion 6 includes a first layer 1 and a second layer 2. The support 3 has a support surface 7 that extends in the image plane along a first axis X in the exemplary Figure 1. Thus, the system 36 is schematically shown in a cross-section perpendicular to the support surface 7. The first layer 1 is disposed between the support surface 7 and the second layer 2.

[0024] The dimensions shown in Figures 1 to 6 are not shown to scale, and the dimensions of the individual elements cannot be inferred from their size ratios to each other. This is a purely schematic representation.

[0025] In all of the exemplary embodiments shown in the figures, as well as in all further embodiments not shown, the second layer 2 is made of at least 90 wt% of the precious metal according to the present invention. This has the advantage that the second layer 2 has corrosion resistance and thus high chemical resistance. Also, the second layer 2 has high conductivity due to the high proportion of precious metal and is thus useful as an electrode for conducting charge and joining to the conductor 4, as shown by way of example in Figures 2 to 6.

[0026] In all embodiments according to the present invention, the first layer 1 is made of a transition metal and / or a metal and / or a metalloid. Further according to the present invention, the first layer 1 has an ultrasonic attenuation effect. Having an ultrasonic attenuation effect is understood to mean reducing the intensity of sound waves crossing a layer having an ultrasonic attenuation effect. This has the advantage that the mechanical stress acting on the support 3 due to vibrations such as ultrasonic waves is reduced. In this way, the mechanical stress acting on the support 3 due to mechanical vibrations occurring during wire bonding is advantageously reduced. In particular, when using a substrate 3 made of oxide ceramics, the adhesive strength of the material bond between the conductor 9 and the second layer 2 after wire bonding increases.

[0027] Preferably, the first layer 1 is at least 10 -4has a mechanical loss coefficient. This has the advantage that the system 36 can be joined by wire bonding while minimizing the mechanical stress on the support so that the risk of damage to the support due to mechanical vibrations is reduced. The loss coefficient is understood to mean the coefficient according to "On the Engineering Properties of Materials", M.F. Ashby, Acta metall, Vol. 37, No. 5, pp. 1273-1293, (1989), where it is called the loss coefficient or attenuation coefficient η (lowercase Greek eta). In Ashby's publication, the loss coefficient is equal to the tangent of the loss angle and equal to the ratio of the loss modulus to the storage modulus, and thus is a dimensionless quantity. In a first approximation, the loss coefficient is inversely proportional to the Young's modulus of a material such as an alloy or metal.

[0028] The elastic modulus of the material always applies to the macroscopic body of the material (also called a macro sample in technical literature) and is determined in accordance with DIN EN ISO 6892-1 and / or DIN EN ISO 6892-2.

[0029] The loss coefficient is determined as described in "A Comprehensive Report on Ultrasonic Attenuation of Engineering Materials, Including Metals, Ceramics, Polymers, Fiber-Reinforced Composites, Wood, and Rocks", Kanji Ono, Appl.Sci, 10, 2230 (2020).

[0030] Particularly preferably, the first layer 1 is at least 10 -4It has a loss coefficient and further has a layer thickness of about 500 nm (nanometers) to about 4 μm (micrometers). In the case of a layer with a thin layer thickness, it has been shown that it is impossible to achieve appropriate mechanical attenuation of mechanical vibrations introduced into the second layer 2 through the first layer 1 and avoid damage to the support. On the other hand, if the thickness of the first layer is too thick, exceeding 4 μm, a decrease in adhesion promotion is caused by residual stress within the layer. This may result in delamination of the layer.

[0031] In one embodiment, the first layer 1 further has a loss coefficient of at least 10 with respect to mechanical vibrations having a frequency of 20 kHz to 200 kHz, preferably 40 kHz to 160 kHz. -4 This is advantageous because wire bonding is usually performed in the frequency range of 20 kHz to 200 kHz, and most commercially available wire bonding apparatuses currently operate at a frequency of 40 kHz to 160 kHz.

[0032] In one embodiment, the first layer 1 further has a Young's modulus of 60 GPa to 130 GPa, preferably 80 GPa to 100 GPa. This is advantageous because the degree to which the layer stretches due to the stress generated by ultrasonic waves is reduced. Since the elongation is equal to the value obtained by dividing the stress by the Young's modulus, this is known from Hooke's law. Therefore, for example, the risk of damage to the first layer 1 itself due to mechanical stress caused by ultrasonic vibrations acting on the first layer is reduced.

[0033] Preferably, the first layer 1 is made of a metal or alloy for which the standard formation enthalpy of the oxide of each metal or alloy is negative in the temperature range up to 350°C. This has the advantage that the first layer 1 exhibits a high adhesive strength with respect to the support 3 as compared with a layer made of an alloy for which the standard formation enthalpy of the oxide is neutral (zero) or positive.

[0034] The fact that the standard formation enthalpy is negative means that the Gibbs oxidation energy is negative in the Ellingham diagram.

[0035] The standard formation enthalpy is determined for the macroscopically solid material of the layer (also known as the macro sample). The determination of the standard enthalpy is carried out in accordance with DIN 51007-1 using calorimetry and Hess's law of constant heat summation (also known as Hess's law).

[0036] Preferably, the first layer 1 is made of bronze. Bronze is also known as a bronze alloy and is a copper alloy.

[0037] The metallization part 6 of its various embodiments is particularly useful in the system 36 where the support 3 is an oxide ceramic. In this case, the support 3 has a modulus of elasticity of 60 GPa to 120 GPa and a linear thermal expansion coefficient of α = 5×10 -6 K -1 ~20×10 -6 K -1 of.

[0038] The linear thermal expansion coefficient refers to the linear thermal expansion coefficient of the layer in the form of a macroscopically solid (also known as the macro sample) or the material of the oxide ceramic. The linear thermal expansion coefficient is determined using a dilatometer in accordance with DIN 51045-1.

[0039] The terms linear thermal expansion coefficient or, abbreviated, linear expansion coefficient and thermal expansion coefficient are used in the same meaning.

[0040] Certain oxide ceramics that are particularly susceptible to damage by mechanical stress have a modulus of elasticity of 90 GPa to 110 GPa and a linear thermal expansion coefficient of α = 12×10 -6 K -1 ~18×10 -6 K -1 is.

[0041] Preferably, the first layer 1 is manufactured as an adhesion promoting layer of the support surface 7 and is connected to the support surface 7 by means of a material connection. Thus, the first layer 1 has both an ultrasonic attenuation effect and an adhesion promoting effect between the second layer 2 and the support 3. This is advantageous for ensuring good bondability between the system and the conductor 9 and the durability of this bond between the conductor 9 and the second layer 2. Not only is damage to the support 3 avoided, but good adhesion of the second layer 2 to the support 3 is also achieved.

[0042] Preferably, the linear thermal expansion coefficient of the first layer 1 is α = 5×10 -6 K -1 ~18×10 -6 K -1 This is advantageous for avoiding thermally induced mechanical stress between the first layer 1 and the substrate 3. Thermally induced mechanical stress occurs when the temperature changes between two materials with significantly different linear thermal expansion coefficients.

[0043] Preferably, the layer thickness of the second layer 2 is 20 nm to 300 nm. The second layer 2 is useful for bonding to the conductor 9 by wire bonding and exhibits good electrical conductivity even with a thin layer thickness of 20 nm. For cost reasons, a layer thickness exceeding 300 nm should be avoided. Furthermore, when the linear thermal expansion coefficients are different, the mechanical stress between the first layer 1 and the second layer 2 may increase as the layer thickness of the second layer increases. When the layer thickness exceeds 300 nm, the second layer 2 exhibits unfavorable residual stress.

[0044] Particularly advantageously, the second layer 2 exhibits high chemical resistance. In this way, the first layer 1 is advantageously protected from the influence of the environment (e.g., oxidation by oxygen). As materials for the second layer 2, gold, platinum, gold alloys, or platinum alloys are particularly useful.

[0045] Particularly advantageously, the second layer 2 exhibits high mechanical resistance. In this way, the first layer 1 is advantageously protected from environmental influences (e.g., mechanical stresses that cause scratches). For this reason, the second layer 2 has a modulus of elasticity exceeding 150 GPa. As the material of the second layer 2, platinum or a platinum alloy is particularly useful. Platinum and platinum alloys are excellent in scratch resistance. A high scratch resistance is ensured by a Mohs hardness exceeding 3A. Advantageously, the second layer 2 has a Mohs hardness exceeding 3. Gold has a Mohs hardness of about 2.5 and is therefore not considered to be scratch resistant. Platinum has a Mohs hardness of 3.4 and is therefore scratch resistant like platinum alloys with a Mohs hardness exceeding 3.

[0046] Particularly preferably, the first layer 1 is a bronze alloy containing copper, tin, and nickel. Preferably, the first layer (1) contains 84.5 wt% - 87.5 wt% of copper, 11 wt% - 13 wt% of tin, and 1.5 wt% - 2.5 wt% of nickel. Particularly preferably, the first layer 1 contains up to 16 wt% of elements other than copper, tin, and nickel. This type of bronze alloy has a particularly advantageous modulus of elasticity (e-modulus) of about 90 GPa and a particularly advantageous coefficient of thermal expansion of 17.5×10 -6 K -1 It has been shown. Therefore, the second layer 2 is a particularly suitable adhesion promoter having an ultrasonic attenuation effect on a specific oxide ceramic having a modulus of elasticity of 90 GPa - 110 GPa and a linear coefficient of thermal expansion of α = 12×10 -6 K -1 ~18×10 -6 K -1 For achieving good bondability of the system by wire bonding, the modulus of elasticity of the first layer 1 preferably differs from the modulus of elasticity of the support 3 by 20% or less, preferably 10% or less. It has been shown that in order for the system 36 to achieve particularly excellent resistance to damage of the support 3, the coefficient of thermal expansion of the first layer 1 should not differ from the coefficient of thermal expansion of the support 3 by more than 20%, preferably more than 10%.

[0047] The metallization part 6 is particularly useful for the support 3 made of a piezoelectric material (preferably, a piezoelectric crystal). The piezoelectric material is often used in situations where a mechanical load acts, for example, as an actuator that applies a voltage to the support surface, or as a piezoelectric measurement element to which a mechanical force is applied to the support surface 7. The metallization part 6 described in this specification is particularly robust against external mechanical shocks due to its mechanical resistance.

[0048] As illustrated in FIGS. 2 and 3, the support 3 provided with the metallization part 6 is often joined to a conductor. The support 3 joined in this way is called a joining system 364. The joining system 364 includes the support 3, at least one metallization part 6, and at least one conductor 4. The conductor 4 includes a first conductor end 8 and a second conductor end 9. The first conductor end 8 is connected to the second layer 2 by an intermaterial connection. The second layer 2 exhibits good joinability with the conductor 4. The conductor 4 is, for example, a bonding wire, preferably a gold bonding wire or an aluminum bonding wire.

[0049] In the joining system 364, the conductor 4 is joined to the second layer 2 by an intermaterial join, preferably by a ball joint 5 as shown in FIG. 2, or by a wedge joint 5 as shown in FIG. 3.

[0050] FIGS. 4 to 6 exemplarily show some embodiments of the joining system 364. However, the embodiments are not limited to the examples shown. Therefore, in particular, other types of partial coatings of the support surface 7 or different geometric configurations of the support are also conceivable. Similarly, it should be explicitly noted that only one or two joins with the conductor 4 are exemplarily shown. However, it is possible to have multiple joins with multiple conductors 4.

[0051] FIG. 4 shows a support 3 in the shape of a rectangular parallelepiped. One of the surfaces functions as a support surface 7 and is partially covered by a strip-shaped metallization portion 6 shown as a dotted surface. The metallization portion 6 is connected to the conductor 4 at a first conductor end 8 (not shown in FIGS. 4 to 6 for clarity but shown in FIGS. 2 and 3) by a material connection portion 5. In this case, and also in FIGS. 2 to 6, the conductor is represented as having an arbitrary length as shown by a curved outer edge. The second end of the conductor is not shown. A person skilled in the art can also design a metallization portion as a conductive path on the support 3 as in FIG. 4.

[0052] FIG. 5 shows an example in which the upper and lower surfaces of the support 3 in the shape of a rectangular parallelepiped are each completely covered by a metallization portion 6. Each metallization portion 6 is connected to the conductor 4 at a first conductor end 8 by a material connection portion 5. This example can be used, for example, as a piezoelectric measurement element showing a piezoelectric transverse effect in which piezoelectric charges can be extracted by the metallization portion 6 when a lateral force is applied to the support 3 in the shape of a rectangular parallelepiped. When the support is configured as a piezoelectric measurement element, each second end 9 of the conductor (not shown) is usually conductively connected to a charge amplifier or an impedance converter (both not shown). A person skilled in the art can also provide an edge region of the upper and lower surfaces without metallization (not shown) in order to avoid lateral junctions.

[0053] FIG. 6 is an example in which the upper and lower surfaces of the disk-shaped support 3 are each completely covered by the metallization portion 6. The side surface includes two partial regions including the metallization portion 6 electrically connected to the metallization portions on the upper and lower surfaces respectively, and in this example, each of them forms the metallization portion 6, that is, a total of two metallization portions 6 electrically separated from each other are formed. This example shows that the metallization portion 6 can also be configured to extend beyond the edge of the support 3, that is, it can be adapted to the topography of the support 3. Each metallization portion 6 is connected to the partial region on the side surface by the conductor 4 at the first conductor end 8 through the material connection portion 5. This example can be used, for example, as a piezoelectric measurement element showing a piezoelectric longitudinal effect in which piezoelectric charges can be extracted by the metallization portion 6 when a force is applied along the vertical axis of the cylindrical support 3. When the support is configured as a piezoelectric measurement element, the respective second ends 9 of the conductors (not shown) are usually conductively connected to a charge amplifier or an impedance converter (both not shown).

[0054] System 34 is manufactured, for example, by providing the support 3 in a first step. The support 3 includes a support surface 7 to which the first layer 1 is attached in a second step. Generally, the first layer 1 is attached to the support surface 7 by sputtering, also known as cold cathode sputtering, or by vapor deposition. The shaping of the first layer 1 is achieved by masking and / or laser structuring of the support surface 7. In a third step, a second layer 2 is attached on the first layer 1. Generally, the second layer 2 is also attached to the support surface 7 by sputtering or vapor deposition. The shaping of the second layer 2 is performed by masking and / or laser structuring of the support surface 7. The second layer can also be attached by an electroplating process. It is also possible to perform laser structuring after attaching the first layer 1 and the second layer 2.

[0055] Unless otherwise specified, all information provided regarding physical parameters and characteristics refers to a temperature of 20°C and a normal ambient pressure (atmospheric pressure) of 101.3 kPa (kilopascals).

[0056] Embodiments that include combinations of the configurations of the embodiments described in this specification are also explicitly included in this specification.

Description of Reference Numerals

[0057] 1 First layer 2 Second layer 3 Support 4 Conductor, bonding wire 5 Connection part, joint part, material connection part, ball bond, wedge bond 6 Metallization part 7 Support surface 8 First conductor end 9 Second conductor end 12 Contact surface 13 Contact surface 36 System 364 Bonding system X First axis Y Second axis Z Third axis

Claims

1. A system (36) comprising a support (3) and at least one metallization (6), The metallization (6) comprises at least a first layer (1) and a second layer (2), the support is an oxide ceramic; The support (3) comprises a support surface (7), The first layer (1) is disposed between the support surface and the second layer (2); said second layer (2) being made of at least 90% by weight of a precious metal; In the system (36), the first layer (1) is made of transition metals and / or metals and / or metalloids, The first layer (1) has an ultrasonic attenuation effect, The first layer (1) has at least 10 －４ and a layer thickness between 500 nm and 4 μm.

2. The first layer (1) has a resistance of at least 10 to mechanical vibrations having a frequency of 20 kHz to 200 kHz, preferably 40 kHz to 160 kHz. －４ 2. The system (36) of claim 1, characterized in that it has a loss factor of:

3. A system (36) according to claim 1 or 2, characterized in that the first layer (1) has an elastic modulus between 60 GPa and 130 GPa, preferably between 80 GPa and 100 GPa.

4. The first layer (1) is made of a metal or an alloy, and the metal or alloy has a negative standard enthalpy of formation of an oxide of the metal or alloy in a temperature range up to 350° C.; System (36) according to any one of claims 1 to 3, characterized in that said first layer (1) is made of bronze or a copper alloy.

5. The support (3) has an elastic modulus of 60 GPa to 120 GPa and a coefficient of elasticity of α=5×10 －６ K －１ ~20 x 10 －６ K －１ , preferably α=6×10 －６ K －１ ~18×10 －６ K －１ , and particularly preferably α=12×10 －６ K －１ ~18×10 －６ K －１ or The support (3) has an elastic modulus of 90 GPa to 110 GPa and a coefficient of elasticity of α=12×10 －６ K －１ ~18×10 －６ K －１ The system (36) according to any one of claims 1 to 4, characterized in that it is an oxide ceramic having a linear thermal expansion coefficient of

6. said first layer (1) being configured as an adhesion-promoting layer for said support surface (7) and being connected to said support surface (7) by a material-to-material connection; The first layer (1) has a value of α=5×10 －６ K －１ ~18×10 －６ K －１ The system (36) according to any one of claims 1 to 5, characterized in that it has a thermal expansion coefficient of

7. The system (36) according to any one of the preceding claims, characterized in that the second layer (2) has a layer thickness of 20 nm to 300 nm.

8. The system (36) according to any one of the preceding claims, characterized in that the second layer (2) has high mechanical resistance and is, for example, made of platinum or a platinum alloy with a platinum content of at least 90% by weight.

9. The first layer (1) is a bronze alloy containing copper, tin, and nickel; Preferably, the first layer (1) comprises 84.5% to 87.5% by weight copper, 11% to 13% by weight tin, and 1.5% to 2.5% by weight nickel; A system (36) according to any one of the preceding claims, characterized in that the first layer (1) contains up to 16% by weight of elements other than copper, tin and nickel.

10. A system (36) according to any one of the preceding claims, wherein the modulus of elasticity of said first layer (1) differs from the modulus of elasticity of said support (3) by no more than 20%, preferably by no more than 10%.

11. A system (36) according to any one of the preceding claims, wherein the thermal expansion coefficient of the first layer (1) differs from the thermal expansion coefficient of the support (3) by no more than 20%, preferably no more than 10%.

12. The system (36) according to any one of the preceding claims, wherein the support (3) is a piezoelectric material, preferably a piezoelectric crystal.

13. A system (36) according to any one of the preceding claims, characterized in that the second layer (2) has an elastic modulus greater than 150 GPa.

14. The system (36) according to any one of the preceding claims, characterized in that the second layer (2) has a high scratch resistance, the second layer (2) having a Mohs hardness of greater than 3.

15. A joint system (364), The joint system (364) comprises: At least one conductor (4); A system comprising a support (3) according to any one of claims 1 to 12 and at least one metallization (6). Including, The conductor (4) comprises a first conductor end (8) and a second conductor end (9); The first conductor end (8) is joined to the second layer (2); The second layer (2) has good adhesion to the conductor (4), the conductor (4) being, for example, a gold bonding wire or an aluminum bonding wire, a bonding system (364).

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