Electrical Feedthroughs

Abstract

The present invention relates to a feedthrough (10) comprising a base (20) having at least one through hole (22) therethrough, an insulating material (30) contained within the through hole (22) through the base (20), and at least one conductor (40) passing through the insulating material (30) contained within the through hole (22), wherein the base (20) comprises titanium or a titanium alloy, the insulating material comprises glass, and the insulating material (30) has a contact angle (θ) with the base (20) of less than 90 degrees in at least some areas.

Description

[Technical field]

[0001] The present invention relates to an electrical feedthrough comprising a metal-containing substrate containing a glass-containing insulating material having an electrical conductor passing therethrough.

[0002] Electrical feedthroughs with an outer metal substrate and an inner glass part acting as an insulator through which one or more conductors pass (glass-metal feedthroughs) are used in many applications, in particular as gas-tight wall parts such as housing elements. Corresponding parts are used, for example, in the field of medical technology, e.g. in implantable medical devices (IMD), in the field of oil and / or gas exploration, in the aviation field and in many other fields, where, on the one hand, different requirement profiles must be taken into account depending on the field of application, and, on the other hand, there are commonalities with regard to the optimization and further development of known solutions.

[0003] In general, it would be desirable, and is an object of the present invention, to, for example, increase the resistance of such feedthroughs to physical and / or chemical influences, improve the hermeticity of the insulating material with respect to the surrounding substrate and / or conductors penetrating the insulating material, optimize the manufacture of such feedthroughs, and / or reduce the manufacturing costs.

[0004] For this reason, it may be particularly advantageous and be an aspect of the subject matter of the invention to better match the properties of the substrate and the properties of the insulating material and / or the conductor passing through the insulating material with one another, which includes in particular the selection of the materials or material compositions of the individual components.

[0005] With regard to the use of feedthroughs in medical technology, it is furthermore usually desirable, and an aspect of the subject matter of the present invention, that the components used are free of toxic effects when they may come into contact with body fluids at least temporarily or even permanently (in the case of implants). This concerns in particular glasses (due to leaching effects) as well as substrates and electrical conductors, so that here it can be provided in particular to carry out cytotoxicity tests in advance, for example before carrying out further suitability tests for medical devices or implants.

[0006] To solve this problem, the present invention provides a feedthrough comprising a base, at least one through hole through the base, an insulating material contained within the through hole through the base, and at least one conductor passing through the insulating material contained within the through hole, wherein the base comprises titanium or a titanium alloy, the insulating material comprises glass, and the insulating material has a contact angle with the base of less than 90 degrees in at least some areas.

[0007] By providing a substrate comprising or consisting of titanium or a titanium alloy (e.g. titanium grade 1, titanium grade 2, titanium grade 3, titanium grade 4 or titanium grade 5, in particular TiAl6V4 alloy) and an insulating material comprising or consisting of glass, at least in some areas with a contact angle of less than 90 degrees, the hermeticity of the insulating material to the surrounding substrate can in particular be improved or the feedthrough can be made more resistant to physical and / or chemical influences. In particular, a higher mechanical durability can be achieved. With a contact angle of less than 90 degrees, in particular an improved glass seal can be achieved, for example the accumulation of liquid at the material transition can be reduced, so that for example stress cracks can be avoided. The use of titanium or a titanium alloy allows high corrosion resistance, high strength, in particular at a relatively low density, and / or avoidance of cytotoxicity, in particular for use in the medical field.

[0008] For the transition from the insulating material to the substrate, it can be provided that the contact angle of the insulating material on the substrate is between 56 and 86 degrees, advantageously between 62 and 84 degrees, particularly preferably between 68 and 82 degrees, even more preferably between 70 and 80 degrees.

[0009] Furthermore, it can be provided that, with regard to the transition from the insulating material to the conductor, the insulating material, at least in some areas, has a contact angle with the conductor of 56 to 86 degrees, advantageously 62 to 84 degrees, particularly preferably 68 to 82 degrees and even more preferably 70 to 80 degrees.

[0010] The electrical conductor may comprise or consist of a material such as a metal, for example a NiFe alloy, niobium, platinum, a platinum alloy and / or molybdenum. The electrical conductor may have a thermal expansion coefficient of 5-9 ppm / K, advantageously 7-9 ppm / K, which, when combined with a substrate comprising or consisting of titanium, allows to provide a pressurized glass seal, thereby enhancing mechanical robustness.

[0011] The insulating material preferably provides an electrical insulation of at least 1 GΩ, especially at temperatures of 175° C. or 200° C. Furthermore, it preferably provides a flashover resistance of at least 1 V / μm, especially at these temperatures.

[0012] Regarding the glass composition, the insulating glass is B 2 O 3 and SiO 2 The glass composition includes, in weight percent, SiO 2 B in weight percent of 2 O 3 It can be provided that the ratio of the proportions is at least 0.45, advantageously at least 0.47 and particularly preferably at least 0.49.

[0013] Here, the insulating material glass is B 2 O 3 and SiO 2 The glass composition includes, in weight percent, SiO2 B in weight percent of 2 O 3 The ratio of the proportions can be between 0.45 and 0.65, advantageously between 0.47 and 0.64, particularly preferably between 0.49 and 0.63.

[0014] Regarding the glass composition, the insulating glass is B 2 O 3 The glass composition includes B. 2 O 3 It can also be provided that the proportion of is at least 21% by weight, advantageously at least 22% by weight, particularly preferably at least 23% by weight or at least 25% by weight.

[0015] Here, the insulating material glass is B 2 O 3 The glass composition includes B. 2 O 3 can be between 21 and 33% by weight, advantageously between 22 and 32% by weight, particularly preferably between 23 and 31% by weight or between 25 and 30% by weight.

[0016] In some cases, the use of titanium or titanium alloys results in the formation of the glass-forming oxide SiO 2 A particularity arises that B reacts with titanium to form titanium silicides, which can lead to peeling phenomena at the glass-metal contact. This problem can be reduced or avoided by the above mentioned data, especially regarding the glass composition. In particular, B 2 O 3 The above data on can suppress this reaction and produce a TiB layer, which provides a more chemically and mechanically stable bond between the titanium-containing component and the glass.

[0017] In principle, it should be noted that titanium is highly reactive. The above-mentioned glass composition allows titanium to convert to SiO during melting (e.g. at melting temperatures of 700-900 °C). 2The reaction with the silicon dioxide gas to form titanium silicide can reduce or avoid the formation of bubbles, for example at the interface, that accompanies this reaction.

[0018] The glass of the insulating material can have a softening temperature of at most 750°C, advantageously at most 700°C, particularly preferably at most 680°C.

[0019] The glass of the insulating material may have a ball softening temperature of at most 850°C, advantageously at most 800°C, particularly preferably at most 780°C.

[0020] The glass of the insulating material can have a hemisphere temperature of at most 950°C, advantageously at most 900°C, particularly preferably at most 850°C.

[0021] The glass of the insulating material can have a flow temperature of at most 1050°C, advantageously at most 1000°C, particularly preferably at most 950°C.

[0022] Regarding glass sealing in titanium, it should be noted that the phase transition temperature of pure titanium is 880° (α / β), which is higher for titanium grade 5 (TiAl6V4), but the reaction mechanism at the interface with glass is the same.

[0023] Due to the above-mentioned characteristics, for example, the glass composition is B 2 O 3 If it does have a boron content, it is advantageous to be able to fully retain the boron content upon melting.

[0024] Additionally, the glass of the insulating material is preferably durable when stored in saline solution at 37.5°C.

[0025] Regarding the glass composition, further advantageous components are defined below.

[0026] For example, the insulating material glass is made of Al 2 O 3 The glass composition contains Al.2 O 3 It can be provided that the proportion of is at least 3% by weight, advantageously at least 7% by weight and particularly preferably at least 9% by weight.

[0027] Here, the insulating glass is Al 2 O 3 The glass composition contains Al. 2 O 3 can be between 3 and 17% by weight, advantageously at least 7 and 16.5% by weight and particularly preferably at least 9 and 15% by weight.

[0028] The values ​​mentioned above advantageously enable increased chemical resistance in particular.

[0029] Furthermore, the insulating material glass is made of Na 2 The glass composition may include NaO. 2 The proportion of O is at least 10% by weight, advantageously at least 12% by weight.

[0030] Regarding the glass composition, further components which are advantageously included only to a limited extent are specified below.

[0031] For example, it can be provided that the glass of the insulating material has a glass composition which comprises CaO, the proportion of CaO in the glass composition being at most 11% by weight, advantageously at most 10% by weight, particularly preferably at most 7% by weight.

[0032] Furthermore, the insulating material glass is made of TiO 2 The glass composition may include TiO 2 The proportion of is at most 10% by weight, advantageously at most 5% by weight and particularly preferably at most 4.5% by weight.

[0033] With regard to the glass composition, further components which are advantageously not present, substantially not present or only present to a limited extent are defined below.

[0034] For example, the insulating material glass is 2 Contains no O or no K 2 The glass composition contains O, and K in the glass composition 2 It can be provided that the proportion of O is less than 7% by weight, advantageously less than 5% by weight and particularly preferably less than 3% by weight.

[0035] The insulating material glass is LiO 2 Does not contain LiO 2 The glass composition may also include LiO 2 is less than 2% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight. This can be advantageous, especially for cost reasons. Furthermore, this can be advantageous with respect to avoiding undesirable reactions with medicaments.

[0036] It can further be provided that the glass of the insulating material has a glass composition which is free of MgO or which comprises MgO, the proportion of MgO in the glass composition being less than 10% by weight, advantageously less than 6.5% by weight and particularly preferably less than 5% by weight.

[0037] The insulating material glass is ZrO 2 Does not contain or ZrO 2 The glass composition may further include a glass composition comprising ZrO 2 is less than 0.9% by weight, preferably less than 0.5% by weight, particularly preferably less than 0.1% by weight. This can, for example, advantageously reduce the viscosity of the glass and improve the glass sealing. Furthermore, this can also be advantageous in terms of cost.

[0038] The insulating material glass is La 2 O 3 Does not contain or La 2 O 3 The glass composition contains La 2 O 3It can be provided that the proportion of is less than 1.5% by weight, advantageously less than 1% by weight and particularly preferably less than 0.5% by weight. This can be advantageous, especially for cost reasons.

[0039] Furthermore, the insulating material glass is Ta 2 O 5 Does not contain Ta 2 O 5 The glass composition includes Ta. 2 O 5 It can be provided that the proportion of is less than 2% by weight, advantageously less than 1% by weight and particularly preferably less than 0.5% by weight. This can be advantageous, especially for cost reasons.

[0040] The insulating glass is made of Nb 2 O 5 Does not contain or Nb 2 O 5 The glass composition may also include Nb 2 O 5 The proportion of Nb is less than 2% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight. This can be advantageous, in particular for cost reasons. Furthermore, Nb 2 O 5 If the proportion is too high, the polyvalence may adversely affect glass sealing.

[0041] With regard to the glass composition, further components which are advantageously not included, substantially not included or only included to a limited extent, in particular with regard to avoiding cytotoxicity, are defined below.

[0042] In particular, it can be provided that the glass of the insulating material has a glass composition which is free of PbO or which comprises PbO, the proportion of PbO in the glass composition being less than 0.05% by weight, advantageously less than 0.03% by weight, particularly preferably less than 0.01% by weight. The glass can therefore in particular be substantially free of PbO.

[0043] It can further be provided that the glass of the insulating material has a glass composition that is free of BaO or that contains BaO, the proportion of BaO in the glass composition being less than 10% by weight, advantageously less than 7% by weight, particularly preferably less than 5% by weight. The glass can in particular be substantially free of BaO. This can be advantageous in terms of avoiding toxicity.

[0044] Glass is an insulating material, 2 O 5 Does not contain or V 2 O 5 The glass composition may also include a glass composition comprising V 2 O 5 is less than 0.5% by weight, advantageously less than 0.3% by weight and particularly preferably less than 0.1% by weight, which can be advantageous both in terms of avoiding toxicity and for cost reasons.

[0045] In addition, the insulating material glass is Bi 2 O 3 Does not contain or Bi 2 O 3 The glass composition may include Bi 2 O 3 is less than 2% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight, which can be advantageous with regard to the reaction with platinum.

[0046] The insulating material glass is WO 3 Does not contain or WO 3 The glass composition includes WO 3 It can also be provided that the proportion of is less than 2% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight, which can be advantageous in terms of avoiding components that are sensitive to changes in oxidation state.

[0047] Furthermore, the insulating material glass is MoO 3 Does not contain or MoO 3 The glass composition may include MoO 3is less than 2% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight, which can be advantageous in terms of avoiding components with a sensitive oxidation state.

[0048] Overall, avoiding multivalent components can be advantageous since their interactions with the environment are partly unknown and therefore can be provided.

[0049] Regarding the coefficient of thermal expansion (CTE) of the glass, it can be provided that the glass of the insulating material has a CTE (20°C; 300°C) in the range of 5 to 10 ppm / K, advantageously in the range of 6 to 9 ppm / K and particularly preferably in the range of 7 to 8 ppm / K.

[0050] This makes it possible to achieve material matching, particularly with titanium or a titanium alloy, and thus improves the air tightness, particularly the hermetic sealability, of the feedthrough.

[0051] The insulating material glass has a density of 2.30 to 2.45 g / cm 3 in the range of 2.32 to 2.43 g / cm 3 In particular, the range of 2.33 to 2.42 g / cm 3 The density can range from 0.01 to 0.01.

[0052] Furthermore, the glass of the insulating material has a glass transition temperature T g It may be provided that the

[0053] In particular, the glass of the insulating material has a glass transition temperature T in the range of 440 to 590 ° C, advantageously in the range of 460 to 570 ° C, in particular in the range of 480 to 550 ° C. g In principle, the glass transition temperature T g A low value can be advantageous in terms of processing.

[0054] In one development, the feedthrough can allow for optical signal transmission in addition to electrical signal transmission by electrical conductors.

[0055] In particular, for this purpose, the insulating material has a light transmittance T along the through hole through the substrate from one outer surface to the other outer surface of at least 25%, advantageously at least 50%, particularly preferably at least 75%, for at least one wavelength in the spectral range from 380 nm to 780 nm. vis may have the following structure:

[0056] The feedthrough may further include an optical interface for transmitting light along a through hole through the substrate and through the insulating material.

[0057] Preferably, the insulating material does not include graphite particles on at least one outer surface, in particular when the insulating material is fused to the through hole without applying pressure to the outer surface, in particular without applying pressure to the outer surface with a carbon weight.

[0058] With regard to hermetic sealing, the contact area between the insulating material and the substrate and / or the feedthrough must be less than 1×10 -8 mbar·l / s, advantageously less than 1×10 -9 mbar·l / s, particularly preferably less than 1×10 -10 It may be provided that the insulating material contained within the through hole of the substrate is in contact with the substrate and / or at least one conductor so as to exhibit a hermetic seal characterized by a helium leak rate of less than mbar·l / s.

[0059] The hermetic sealability of the feedthrough can be confirmed, for example, by a helium leak test.

[0060] Advantageously, the feed-through comprises a number of electrical conductors passing through an insulating material accommodated in the through-bore, advantageously at least two electrical conductors, particularly preferably at least ten electrical conductors.

[0061] The substrate may include a number of through holes, in which an insulating material is respectively accommodated, and in each case at least one, in particular exactly one, electrical conductor passes through the insulating material of the through hole.

[0062] The substrate comprising titanium or a titanium alloy may be formed in the shape of a plate. The substrate may have a first surface and an opposing second surface, the through hole forming an inner wall connecting the first surface and the second surface. The substrate may define a plane extending parallel to the first and / or second surface. Along a direction extending parallel to the first and / or second surface and / or along a direction extending in said plane, the substrate may have a dimension larger than the diameter of the through hole, in particular at least twice, in particular at least three times.

[0063] The insulating material located in the through hole can have a contact angle of less than 90° on both sides of the substrate, i.e. on both the first side and the second side, in particular a contact angle having the above-mentioned value. The insulating material can be recessed with respect to the first and / or second side of the substrate. In other words, the insulating material can be accommodated in the through hole so that there is a step with respect to the substrate at the position of the inner wall.

[0064] The substrate may have a thickness perpendicular to its plane that is greater than the thickness of the insulating material on the inner wall of the through hole. The substrate may also have this thickness over a dimension extending along the first and / or second face and / or the plane, for example the substrate may have this thickness over at least twice the diameter of the through hole, in particular over three times the diameter.

[0065] The conductors passing through the insulating material can protrude from one or both sides of the insulating material and / or the substrate. In particular, the conductors can protrude from the first and / or second side of the substrate. The protrusions on one or both sides can be greater than the thickness of the substrate at the inner wall, in particular at least twice as large, in particular at least three times as large. The protrusions can be greater on one side than on the other side, in particular at least twice as large, in particular at least three times as large.

[0066] The invention relates in particular to such a feedthrough for an implant and / or to an implant comprising such a feedthrough, in which the glass of the insulating material is non-cytotoxic, in particular when measured in accordance with the standard according to EN ISO 10993-5 (July 2009 edition).

[0067] In this context, but in principle and generally, it can be provided that the feedthrough has at least two conductors spaced apart by less than 5 mm, advantageously less than 1 mm.

[0068] Furthermore, in this context, but also generally, it can be provided that the maximum dimension of the through holes through the base, in a direction perpendicular to the axis of the conductor, is less than 10 mm, advantageously less than 2 mm.

[0069] The invention further relates in particular to such a feedthrough for an oil / gas exploration device and / or to an oil / gas exploration device equipped with such a feedthrough, wherein the feedthrough has an impact resistance of at least 100 g, advantageously at least 500 g, particularly preferably at least 750 g, and / or withstands such impact loads while retaining its hermetic sealing properties, in particular the above-mentioned hermetic sealing properties.

[0070] Furthermore, in this context, but in principle and generally, it can be provided that the feedthrough exhibits a vibration resistance of at least 20 grms, advantageously at least 40 grms, particularly preferably at least 60 grms, and / or withstands such vibration loads while retaining its hermetic sealability, in particular the above-mentioned hermetic sealability.

[0071] Furthermore, in this context, but in principle and generally, it can be provided that the substrate is of non-magnetic structure.

[0072] The invention further relates in particular to such a feedthrough for a wearable device and / or to a wearable device comprising such a feedthrough.

[0073] The invention will now be described in more detail with reference to the drawings and some example embodiments. [Brief description of the drawings]

[0074] [Figure 1] FIG. 2 is a schematic diagram of a feedthrough according to a first embodiment. [Diagram 2] 2 is a schematic cross-sectional view of the feedthrough shown in FIG. 1 with the contact angle between the insulating material and the substrate or conductor plotted. [Diagram 3] FIG. 4 is a schematic diagram of a feedthrough according to a second embodiment. [Figure 4] FIG. 11 is a schematic diagram of a feedthrough according to a third embodiment.

[0075] With reference to Figure 1, the feedthrough has an outer substrate 20 through which one or more (here two) through-holes 22 pass, each with an insulating material 30 inserted therein through which at least one conductor 40 extends, where the conductors may protrude from one or both sides (in this case both) of the insulating material. The feedthrough shown has two inner conductors (pins) and can therefore be described as a two-pole feedthrough. It is also possible for the substrate 20 to function as the outer conductor and thus form further conductors.

[0076] With reference to FIG. 2, the insulating material 30 inserted in the through hole 22 has a contact angle θ with the surrounding substrate 20 that is less than 90 degrees. Furthermore, the insulating material 30 can advantageously also have a contact angle θ' with the conductor 40 that is less than 90 degrees. In principle, to achieve this or a given contact angle θ or θ', a weight, for example a carbon mold, can be used during the fusion of the insulating material 30 into the through hole 22. However, this may become impractical when the number of pins is high. However, it is also possible to fuse the insulating material into the through hole 22 in such a way that a contact angle θ<90° is formed on the substrate material already based on the wetting properties of the insulating material, whereby the weight can be dispensed with and there are no carbon particles on the outer surface of the insulating material 30. In particular, the term contact angle is synonymous with the term wetting angle.

[0077] 3 and 4, a feedthrough can have multiple inner conductors (pins), so that, for example, a 17-pin feedthrough (FIG. 3) or a 30-pin feedthrough (FIG. 4) can be provided. In the connector shown, each individual inner conductor 40 extends through the insulating material of a single through hole 22. However, multiple or multiple conductors can extend through the same insulating material of the same through hole 22.

[0078] In order for the insulating material 30 to wet the titanium substrate 20 with a contact angle θ<90° (without the use of a weight), the insulating material 30 may be specifically formed as a high borate glass.2 O 3 and SiO 2 The glass composition includes, in weight percent, SiO 2 B in weight percent of 2 O 3 and / or the glass of the insulating material is B 2 O 3 wherein B in the glass composition 2 O 3 It can be provided that the proportion of is at least 20% by weight.

[0079] In particular in the case of high borate glasses and / or glass compositions with the abovementioned boron contents, it may be advantageous for the glass of the insulating material to have a softening temperature of at most 680°C, a ball softening temperature of at most 780°C, a hemisphere temperature of at most 850°C and / or a flow temperature of at most 950°C, preferably at most 940°C, particularly preferably at most 900°C.

[0080] In particular, it can be provided that the glass of the insulating material is sealable at temperatures below 950° C., preferably below 940° C. It is therefore preferable to limit the characteristic flow point obtained with the established Exothermic Heating Microscopy (EHM) methodology to a maximum of 940° C.

[0081] When carrying out glass sealing to titanium or titanium alloys, care should be taken that the process is advantageously carried out not significantly above, or particularly preferably below, the temperature range of the α / β phase transition of titanium.

[0082] According to one example embodiment, the insulating material may include a glass having the following composition in weight percent: SiO 2 35~55 B 2 O 3 20~33 Al 2 O 3 3~23 Na 2 O 5~20 CaO 0~12 TiO 2 0~10.

[0083] According to a further example embodiment, the insulating material may include a glass having the following composition in weight percent: SiO 2 40~51 B 2 O 3 24~30 Al 2 O 3 7~19 Na 2 O 10~17 CaO 0~7 TiO 2 0~7.

[0084] According to a further embodiment example, the insulating material may comprise a glass having the above composition, but with the following proportions in weight percent of B: 2 O 3 Contains: 25.0-28.6.

[0085] According to a further embodiment, the insulating material may comprise a glass having the above-mentioned composition, but with the proviso that it contains the following proportion of MgO in % by weight: less than 5.5, in particular less than 5, in particular less than 4.5.

[0086] According to certain example embodiments, the insulating material can include glasses having any of the following compositions in weight percent (Glass 1 to Glass 5): [Table 1]

[0087] For example embodiments of Glasses 1 to 5, the following glass and powder properties could be determined by Exothermic Heat Microscopy (EHM): [Table 2]

[0088] For Glasses 1 to 5, the sintered bodies were stored in a 0.9% saline solution at 37.5° C.: [Table 3]

[0089] Regarding Glass 1 to Glass 5, the properties of the sintered bodies are shown below: [Table 4]

[0090] The data in the above table shows that Glasses 2 to 5 have higher "galvanic resistance" than Glass 1. Here, "galvanic resistance" essentially means durability against aqueous chemicals (acids, alkalis and electrolytes) used in typical galvanic pretreatment and galvanic coating processes. High temperature degreaser is a high temperature cleaning alkaline liquid for degreasing.

[0091] The insulating glass can also be mixed with coloring components, such as CoO, and pigments, such as spinel-based pigments.

[0092] Additionally, the glass may contain fillers, such as low expansion fillers, such as cordierite, which in some cases may reduce the thermal expansion coefficient of the glass.

[0093] For example, by using an 11% fraction of cordierite (melt for producing cordierite as a filler), the coefficient of thermal expansion (CTE) of the glass can be reduced from 2 ppm / K to a value of about 7.0 ppm / K without significant loss of particularly relevant properties.

[0094] For the salt solution test, a test specimen (e.g. a compact) is prepared from glass powder. This test specimen is mixed with demineralized water until small lumps are produced, then it is manually pressed into a cylindrical shape and sintered under nitrogen at a temperature of about 30-40 °C above the "ball softening" temperature. The weight of the test specimen is usually 0.5 g. The salt solution is 0.9%. In a glass beaker, about 120 ml of salt solution is heated to about 37 °C. The test specimen is placed on the edge of the glass beaker. The magnetic stirrer is set so that the salt solution moves noticeably but the test specimen does not move. The glass beaker is covered with a glass lid so that little concentration differences due to evaporation occur. The weight of the test specimen is measured before the experiment and each day, and the relative mass loss is referred to as a reference value.

[0095] Several comparative glasses (Comparative Example 1 to Comparative Example 4) are listed below, and the characteristics of these were evaluated in the same manner as Glasses 1 to 5 of the above-mentioned Examples.

[0096] Comparative Example Glass: Composition in % by weight: [Table 5]

[0097] Comparative Example Glasses: Glass and Powder Properties by Exothermic Heat Microscopy (EHM): [Table 6]

[0098] Sintered body of comparative glass: Storage at 37.5° C. in 0.9% saline solution: [Table 7]

[0099] Comparative Example: Properties of Sintered Body [Table 8]

[0100] Storage in saline solution shows that the comparative glass, Comparative Example 1, experiences more than 10 times the weight loss compared to the glasses listed above.

[0101] Due to this poor durability when stored in NaCl solution, it was determined that, depending on the specifications, this Comparative Example 1 may be considered unsuitable for applications in contact with body fluids.

[0102] Characterization by EHM revealed that Comparative Example 2, with a hemisphere temperature of about 880°C and a flow temperature of 953°C, was considered to be the limiting values ​​for a suitable feedthrough. Experiments showed that a glass sealing temperature of about 980°C was required for the manufacture of the feedthrough.

[0103] Characterization by EHM revealed that Comparative Example 3, in which the hemisphere temperature was significantly higher than 1000°C, was unable to provide glass sealing at temperatures lower than this, or at temperatures below 900°C, for example.

[0104] The glass of Comparative Example 4 has poor flowability on titanium, and this type of glass has been found to have poor spreading on titanium. In the case of poor spreading and / or insufficient wetting, it may be necessary to apply pressure, for example in the form of a weight. However, such an approach is less preferred, since it is relatively cumbersome, especially for miniaturized designs and / or designs with complex pole shapes, such as designs with many conductors and short distances between these conductors and / or designs with multiple conductors, for example more than 10 conductors.

[0105] Glasses 1-5 and Comparative Glasses 1 and 2 have wetting or contact angles with titanium (without the use of weights) of less than 90° C. This provides a number of advantages in the manufacture of feedthroughs: no need to press a carbon mold against the glass to obtain the desired surface shape, contamination or adhesion of the carbon mold to the glass surface (which can cause insulation problems) is avoided, and the difference in the expansion coefficient of the carbon mold and that of the metal part is not an obstacle in the design of the fused fixation.

[0106] The experimental and comparative glasses were produced by melting the glasses on a 1 liter scale and forming them into casts and ribbons of approximately 1-2 cm width. In particular, the cooled casts were used to measure the density, the coefficient of linear thermal expansion in the range 20°C to 300°C, i.e. CTE(20;300°C), and the viscosity fixed points Tg and Ew according to methods commonly used in the art.

[0107] The coefficient of linear thermal expansion (CTE) in the range of 20°C to 300°C was determined by measuring the length change behavior of a 100 mm long solid by dilatometry.

[0108] Density determinations were performed by buoyancy measurements.

[0109] The determination of the softening temperature Ew (i.e. the temperature at which the viscosity [dPas] of lg is 7.6) was carried out by viscosity measurements on square filaments.

[0110] To determine the powder properties, ribbons of the experimental glasses were ground to a given particle size (K3) and then characterized.

[0111] The overall technique for determining temperatures relevant to glass sealing is Exothermic Heating Microscopy (EHM).

[0112] The powders were then sintered and characterized, and their weight loss was determined after exposure to chemical solutions representative of various treatments in the galvanic process.

[0113] To determine the galvanic resistance, compacts were made from ground powders of the experimental glasses and sintered. The sintered samples were then immersed in a bath simulating galvanic treatment and the mass loss was determined.

[0114] To determine the durability in saline solution, the sintered samples were stored in 0.9% saline solution at 37.5°C for 1 to 24 days, after which the mass loss was determined.

[0115] To determine the cytotoxicity, the experimental glasses were tested for cytotoxic effect according to the standard EN ISO 10993-5: Test for in vitro cytotoxicity. No cytotoxic effect was detected for the glasses according to the invention.

[0116] In the manufacture of feedthroughs, cleaning and coating in galvanic baths can be used, in particular to improve functionality such as weldability, joinability, solderability, etc. The individual components, in particular the glass used, are therefore advantageously designed to withstand such baths.

Claims

1. below: a substrate (20) having at least one through hole (22) therethrough; an insulating material (30) contained within the through-hole (22) through the substrate (20); At least one conductor (40) passing through the insulating material (30) housed in the through hole (22); A feedthrough (10) comprising: the substrate (20) comprises titanium or a titanium alloy, and the insulating material comprises glass; The feedthrough (10) wherein the insulating material (30) has a contact angle (θ) with the substrate (20) of less than 90 degrees in at least some areas.

2. the contact angle (θ) of the insulating material (30) with the substrate (20) is between 56 and 86 degrees, advantageously between 62 and 84 degrees, particularly preferably between 68 and 82 degrees, and even more preferably between 70 and 80 degrees; and / or 2. The feedthrough according to claim 1, wherein the insulating material (30) has a contact angle (θ') with the conductor (40) in at least some areas of 56 to 86 degrees, advantageously 62 to 84 degrees, particularly preferably 68 to 82 degrees, and even more preferably 70 to 80 degrees.

3. The glass of the insulating material is B ２ O ３ and SiO ２ The glass composition includes, in weight percent, SiO ２ B in weight percent relative to the proportion of ２ O ３ is at least 0.45, advantageously at least 0.47, particularly preferably at least 0.49, or The glass of the insulating material is B ２ O ３ and SiO ２ The glass composition includes, in weight percent, SiO ２ B in weight percent relative to the proportion of ２ O ３ 2. The feed-through according to claim 1, wherein the ratio of the proportions is between 0.45 and 0.65, preferably between 0.47 and 0.64, particularly preferably between 0.49 and 0.

63.

4. The glass of the insulating material is B ２ O ３ The glass composition contains B. ２ O ３ is at least 21% by weight, preferably at least 22% by weight, particularly preferably at least 23% by weight or at least 25% by weight, or The glass of the insulating material is B ２ O ３ The glass composition contains B. ２ O ３ 2. The feed-through according to claim 1, wherein the proportion of is from 21 to 33% by weight, preferably from 22 to 32% by weight, particularly preferably from 23 to 31% by weight or from 25 to 30% by weight.

5. the glass of the insulating material has a softening temperature of at most 750°C, preferably at most 700°C, particularly preferably at most 680°C, and / or the glass of the insulating material has a ball softening temperature of at most 850°C, preferably at most 800°C, particularly preferably at most 780°C, and / or the glass of the insulating material has a hemisphere temperature of at most 950°C, preferably at most 900°C, particularly preferably at most 850°C, and / or the glass of the insulating material has a flow temperature of at most 1050°C, preferably at most 1000°C, particularly preferably at most 950°C, and / or 10. The feedthrough of claim 1, wherein said glass of said insulating material is durable when stored in a saline solution at 37.5[deg.]C.

6. The glass of the insulating material is Al ２ O ３ The glass composition contains Al ２ O ３ is at least 3% by weight, advantageously at least 7% by weight, particularly preferably at least 9% by weight, or The glass of the insulating material is Al ２ O ３ The glass composition contains Al ２ O ３ 2. The feed-through according to claim 1, wherein the proportion of is 3 to 17% by weight, preferably at least 7 to 16.5% by weight, particularly preferably at least 9 to 15% by weight.

7. The glass of the insulating material is Na ２ The glass composition contains O, and Na ２ 2. The feed-through according to claim 1, wherein the proportion of O is at least 10% by weight, preferably at least 12% by weight.

8. the glass of the insulating material has a glass composition that contains CaO, the proportion of CaO in the glass composition being at most 11% by weight, preferably at most 10% by weight, particularly preferably at most 7% by weight, and / or The glass of the insulating material is TiO ２ In the glass composition, TiO ２ 2. The feed-through according to claim 1, wherein the proportion of is at most 10% by weight, preferably at most 5% by weight, particularly preferably at most 4.5% by weight.

9. The glass of the insulating material is K ２ Contains no O or K ２ The glass composition contains O, and K in the glass composition ２ the proportion of O is less than 7% by weight, advantageously less than 5% by weight, particularly preferably less than 3% by weight, and / or The glass of the insulating material is LiO ２ does not contain or LiO ２ In the glass composition, LiO ２ 2. The feed-through according to claim 1, wherein the proportion of is less than 2% by weight, preferably less than 1% by weight, particularly preferably less than 0.5% by weight.

10. the glass of the insulating material has a glass composition that is free of MgO or that contains MgO, the proportion of MgO in the glass composition being less than 10% by weight, advantageously less than 6.5% by weight, particularly preferably less than 5% by weight, and / or The glass of the insulating material is ZrO ２ does not contain or ZrO ２ The glass composition contains ZrO ２ 2. The feed-through according to claim 1, wherein the proportion of is less than 0.9% by weight, preferably less than 0.5% by weight, particularly preferably less than 0.1% by weight.

11. The glass of the insulating material is La ２ O ３ does not contain or La ２ O ３ The glass composition contains La ２ O ３ is less than 1.5% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight, and / or The glass of the insulating material is Ta ２ O ５ does not contain Ta ２ O ５ The glass composition contains Ta. ２ O ５ is less than 2% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight, and / or The glass of the insulating material is Nb ２ O ５ does not contain or Nb ２ O ５ The glass composition contains Nb ２ O ５ 2. The feed-through according to claim 1, wherein the proportion of is less than 2% by weight, preferably less than 1% by weight, particularly preferably less than 0.5% by weight.

12. the glass of the insulating material has a glass composition that is PbO-free or PbO-containing, the proportion of PbO in the glass composition being less than 0.05% by weight, advantageously less than 0.03% by weight, particularly preferably less than 0.01% by weight, and / or the glass of the insulating material has a glass composition that is free of BaO or that contains BaO, the proportion of BaO in the glass composition being less than 10% by weight, advantageously less than 7% by weight, particularly preferably less than 5% by weight, and / or The glass of the insulating material is V ２ O ５ does not contain or V ２ O ５ The glass composition contains V ２ O ５ 2. The feed-through according to claim 1, wherein the proportion of is less than 0.5% by weight, preferably less than 0.3% by weight, particularly preferably less than 0.1% by weight.

13. The glass of the insulating material is Bi ２ O ３ does not contain or Bi ２ O ３ The glass composition contains Bi. ２ O ３ is less than 2% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight, and / or The glass of the insulating material is WO ３ does not contain or WO ３ The glass composition contains WO ３ is less than 2% by weight, advantageously less than 1% by weight, particularly preferably less than 0.5% by weight, and / or The glass of the insulating material is MoO ３ does not contain or MoO ３ In the glass composition, MoO ３ 2. The feed-through according to claim 1, wherein the proportion of is less than 2% by weight, preferably less than 1% by weight, particularly preferably less than 0.5% by weight.

14. 2. The feedthrough according to claim 1, wherein the glass of the insulating material has a coefficient of thermal expansion CTE (20°C; 300°C) in the range of 5 to 10 ppm / K, preferably in the range of 6 to 9 ppm / K, particularly preferably in the range of 7 to 8 ppm / K.

15. The glass of the insulating material has a glass transition temperature T ｇ and / or The glass of the insulating material has a glass transition temperature T in the range of 440 to 590° C., preferably in the range of 460 to 570° C., in particular in the range of 480 to 550° C. ｇ The feedthrough of claim 1 , comprising:

16. The insulating material has a light transmittance T along the through hole through the substrate from one outer surface to the other outer surface of at least 25%, advantageously at least 50%, particularly preferably at least 75%, for at least one wavelength in the spectral range of 380 nm to 780 nm. ｖｉｓ and / or The feedthrough of claim 1 , wherein the feedthrough comprises an optical interface for transmitting light through the insulating material along the through hole through the substrate.

17. 2. The feedthrough of claim 1, wherein the insulating material does not include graphite particles on at least one outer surface when the insulating material is fused to the through hole without applying pressure to the outer surface, in particular without applying pressure to the outer surface with a carbon weight.

18. The interface between the insulating material and the substrate and / or the feedthrough is 1×10 －８ mbar l / s, preferably less than 1 x 10 －９ mbar l / s, particularly preferably less than 1 x 10 －１０ 2. The feedthrough of claim 1, wherein the insulating material (30) contained within the through hole (22) of the substrate (20) is in contact with the substrate and / or the at least one conductor (40) so as to exhibit a hermetic seal characterized by a helium leak rate of less than mbar·l / s.

19. 2. The feedthrough according to claim 1, comprising a number of conductors (40), preferably at least two conductors, particularly preferably at least ten conductors, passing through the insulating material (30) housed in the through hole (22).

20. A feedthrough according to any one of claims 1 to 19, in particular for an implant, or an implant with a feedthrough according to any one of claims 1 to 19, the glass of the insulating material is not cytotoxic, in particular as measured in accordance with the standard according to EN ISO 10993-5, and / or at least two conductors have a spacing of less than 5 mm, preferably less than 1 mm; and / or A feedthrough or implant in which the maximum dimension of the through hole through the substrate in a direction perpendicular to the axis of the conductor is less than 10 mm, advantageously less than 2 mm.

21. A feedthrough according to any one of claims 1 to 19, in particular for an oil / gas exploration device or an oil / gas exploration device equipped with a feedthrough according to any one of claims 1 to 19, the feedthrough has an impact resistance of at least 100 g, advantageously at least 500 g, particularly preferably at least 750 g, and / or withstands such impact loads while retaining its hermetic seal; and / or A feedthrough or oil / gas exploration device, wherein said feedthrough exhibits a vibration resistance of at least 20 grms, advantageously at least 40 grms, particularly preferably at least 60 grms, and / or withstands such vibration loads while retaining its hermetic seal.

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