DE102019133789A1 - Planar pH measuring electrode and method for producing the same - Google Patents

Abstract

The invention relates to a glass electrode (1) for an electrochemical ion-sensitive sensor comprising: a substrate (10) with a first substrate surface (11) and an opposite second substrate surface (12), a channel (13) of the first substrate surface (11) extends to the second substrate surface (12), - a glass element (20) with a first glass surface (21) and an opposing second glass surface (22), the first substrate surface (11) and the second glass surface (22) are connected to one another by bonding, the channel (13) being filled with a conductive medium (2) and a discharge electrode (3) being in electrical contact with the conductive medium (2 ').

Description

The invention relates to a planar pH measuring electrode and a method for producing the same.

In analytical measurement technology, especially in the field of water management, environmental analysis, in the industrial field, e.g. in food technology, biotechnology and pharmacy, as well as for a wide variety of laboratory applications, measured variables such as pH value, conductivity, or the concentration of analytes, such as ions or dissolved gases in a gaseous or liquid measuring medium are of great importance. These measured variables can be recorded and / or monitored, for example, by means of electrochemical sensors, such as potentiometric, amperometric, voltammetric or coulometric sensors, or else conductivity sensors.

A pH glass sensor with a glass membrane is often used to measure the pH value. However, the disadvantage of a conventional pH glass sensor is the susceptibility of the glass sensor to breakage and the unfavorable form factor for many purposes, i.e. the size of the glass sensor. One way of reducing the susceptibility of a pH glass sensor to breakage is to mechanically stabilize its glass membrane through a close contact using a (mixed) conductive solid.

Procedures for producing such structures include coatings of metallic and / or ceramic substrates or the metallization of pH glass membranes. Such coatings are, for example, "enamelling", thick-film and thin-film coating processes. The difficulties with these processes include the thermal stress on the glass layers, which leads to thermomechanical damage, for example poor adhesion, crack formation, delamination or substrate corrosion, as well as to the crystallization of the high-performance pH glasses used. In addition, when very thin layers of glass are heated to high temperatures, droplets can form in the glass element used.

It is therefore an object of the invention to provide a method for producing a pH glass membrane which does not have the disadvantages of the prior art described.

This object is achieved according to the invention by a method for producing a glass electrode for an electrochemical ion-sensitive sensor according to claim 1.

• - Bereitstellen eines Substrats mit einer ersten Substratfläche und einer gegenüberliegenden zweiten Substratfläche, eines Glaselements mit einer ersten Glasfläche und einer gegenüberliegenden zweiten Glasfläche, sowie einer elektrischen Kontaktierungseinheit, wobei das Substrat elektrisch leitfähig ist,
• - Aufeinanderlegen der ersten Substratfläche und der zweiten Glasfläche,
• - Erhitzen des Substrats und des Glaselements auf eine vorbestimmte Temperatur, wobei die vorbestimmte Temperatur geringer als eine Glastransformationstemperatur des Glaselements ist,
• - Anlegen einer elektrischen Spannung an das Substrat und das Glaselement, so dass die erste Substratfläche und die zweite Glasfläche durch Bonden miteinander verbunden werden,
• - Kontaktieren des Substrats mit einer Ableitelektrode.

The method according to the invention comprises the following steps:

• - Provision of a substrate with a first substrate surface and an opposing second substrate surface, a glass element with a first glass surface and an opposing second glass surface, and an electrical contacting unit, the substrate being electrically conductive,
• - Laying the first substrate surface and the second glass surface on top of one another,
• Heating the substrate and the glass element to a predetermined temperature, the predetermined temperature being lower than a glass transformation temperature of the glass element,
• - applying an electrical voltage to the substrate and the glass element, so that the first substrate surface and the second glass surface are connected to one another by bonding,
• - Contacting the substrate with a lead electrode.

The method according to the invention makes it possible to produce a glass electrode which has extremely high stability, generates low production costs, enables a very small overall size and can be precisely produced by machine.

The above-mentioned object is also achieved according to the invention by a method for producing a glass electrode for an electrochemical ion-sensitive sensor according to claim 2.

• - Bereitstellen eines Substrats mit einer ersten Substratfläche und einer gegenüberliegenden zweiten Substratfläche, eines Glaselements mit einer ersten Glasfläche und einer gegenüberliegenden zweiten Glasfläche, sowie einer elektrischen Kontaktierungseinheit, wobei sich im Substrat mindestens ein an einer festgelegten Position befindlicher Kanal von der ersten Substratfläche zur zweiten Substratfläche erstreckt,
• - Aufeinanderlegen der ersten Substratfläche und der zweiten Glasfläche,
• - Erhitzen des Substrats und des Glaselements auf eine vorbestimmte Temperatur, wobei die vorbestimmte Temperatur geringer als eine Glastransformationstemperatur des Glaselements ist,
• - Anlegen einer elektrischen Spannung an die zweite Substratfläche und die erste Glasfläche, so dass die erste Substratfläche und die zweite Glasfläche durch Bonden miteinander verbunden werden,
• - Füllen des Kanals mit einem elektrisch leitfähigen Medium,
• - Kontaktieren des elektrisch leitfähigen Mediums mit einer Ableitelektrode.

The method according to the invention comprises the following steps:

• - Provision of a substrate with a first substrate surface and an opposing second substrate surface, a glass element with a first glass surface and an opposing second glass surface, and an electrical contacting unit, with at least one channel located at a fixed position in the substrate from the first substrate surface to the second substrate surface extends,
• - Laying the first substrate surface and the second glass surface on top of one another,
• Heating the substrate and the glass element to a predetermined temperature, the predetermined temperature being lower than a glass transformation temperature of the glass element,
• - Applying an electrical voltage to the second substrate surface and the first glass surface, so that the first substrate surface and the second glass surface are connected to one another by bonding,
• - Filling the channel with an electrically conductive medium,
• - Contacting the electrically conductive medium with a discharge electrode.

The above-mentioned object is also achieved according to the invention by a method for producing a glass electrode for an electrochemical ion-sensitive sensor according to claim 3.

• - Bereitstellen eines Substrats mit einer ersten Substratfläche und einer gegenüberliegenden zweiten Substratfläche, eines Glaselements mit einer ersten Glasfläche und einer gegenüberliegenden zweiten Glasfläche, sowie einer elektrischen Kontaktierungseinheit,
• - Aufeinanderlegen der ersten Substratfläche und der zweiten Glasfläche,
• - Erhitzen des Substrats und des Glaselements auf eine vorbestimmte Temperatur, wobei die vorbestimmte Temperatur geringer als eine Glastransformationstemperatur des Glaselements ist,
• - Anlegen einer elektrischen Spannung an die zweite Substratfläche und die erste Glasfläche, so dass die erste Substratfläche und die zweite Glasfläche durch Bonden miteinander verbunden werden,
• - Ausbilden eines Kanals in dem Substrat, so dass sich der Kanal von der ersten Substratfläche bis zur zweiten Substratfläche erstreckt,
• - Füllen des Kanals mit einem elektrisch leitfähigen Medium,
• - Kontaktieren des elektrisch leitfähigen Mediums mit einer Ableitelektrode.

The method according to the invention comprises the following steps:

• - Provision of a substrate with a first substrate surface and an opposing second substrate surface, a glass element with a first glass surface and an opposing second glass surface, and an electrical contacting unit,
• - Laying the first substrate surface and the second glass surface on top of one another,
• Heating the substrate and the glass element to a predetermined temperature, the predetermined temperature being lower than a glass transformation temperature of the glass element,
• - applying an electrical voltage to the second substrate surface and the first glass surface, so that the first substrate surface and the second glass surface are connected to one another by bonding,
• - Forming a channel in the substrate, so that the channel extends from the first substrate surface to the second substrate surface,
• - Filling the channel with an electrically conductive medium,
• - Contacting the electrically conductive medium with a discharge electrode.

According to one embodiment of the invention, the first substrate surface and the second glass surface have an average roughness of less than 50 nm. The first substrate surface and the second glass surface preferably have an average roughness of less than 10 nm.

According to one embodiment of the invention, the mean roughness is achieved by a step of polishing the first substrate surface and the second glass surface.

According to one embodiment of the invention, the first substrate surface and the second glass surface are parallel surfaces. The first substrate surface and the second glass surface are preferably parallel planar surfaces.

According to one embodiment of the invention, the applied electrical voltage is less than 5 kV. The applied electrical voltage is preferably between 100 V and 1000 V. The applied electrical voltage is particularly preferably between 200 V and 500V.

According to one embodiment of the invention, a negative voltage is applied to the first glass surface and a positive voltage is applied to the second substrate surface.

According to one embodiment of the invention, the predetermined temperature is lower than the transformation temperature of the glass element. Preferably the predetermined temperature is between 200 ° C and 500 ° C.

According to one embodiment of the invention, the glass element contains lithium or sodium.

According to one embodiment of the invention, the glass element has a thickness of less than 1000 μm. The glass element preferably has a thickness between 1 μm and 500 μm. The glass element particularly preferably has a thickness between 10 μm and 100 μm.

According to one embodiment of the invention, the conductive medium comprises a conductive polymer, a carbon-based material or another conductive inorganic material.

According to one embodiment of the invention, the conductive medium comprises a metal. Preferably the conductive medium comprises coin metal. The conductive medium particularly preferably comprises copper.

According to one embodiment of the invention, the conductive medium comprises a fluid. The fluid preferably comprises a molten salt, an ionic liquid or a liquid with a redox addition.

According to one embodiment of the invention, the substrate is conductive. The substrate preferably comprises a metal, a carbon-based material, a semiconductor or a conductive composite material.

According to one embodiment of the invention, a step of cleaning the first substrate surface and the second glass surface takes place before the step of placing the first substrate surface and the second glass surface on top of one another.

The object according to the invention is also achieved by a glass electrode for an electrochemical ion-sensitive sensor according to claim 10.

The glass electrode according to the invention comprises a substrate with a first substrate surface and an opposing second substrate surface and a glass element with a first glass surface and an opposing second glass surface. The first substrate surface and the second glass surface are connected to one another by bonding. A lead electrode is in electrical contact with the substrate.

The object according to the invention is also achieved by a glass electrode for an electrochemical ion-sensitive sensor according to claim 11.

The glass electrode according to the invention comprises a substrate with a first substrate surface and an opposing second substrate surface, a channel in the substrate extending from the first substrate surface to the second substrate surface, and a glass element with a first glass surface and an opposing second glass surface. The first substrate surface and the second glass surface are connected to one another by bonding. The channel is filled with a conductive medium and a discharge electrode is in electrical contact with the conductive medium.

According to one embodiment of the invention, the glass element comprises lithium or sodium.

According to one embodiment of the invention, the glass element has a thickness of less than 1000 μm. The glass element preferably has a thickness between 1 μm and 500 μm. The glass element particularly preferably has a thickness between 10 μm and 100 μm.

According to one embodiment of the invention, the conductive medium comprises a metal. Preferably the conductive medium comprises coin metal. The conductive medium particularly preferably comprises copper or silver.

According to one embodiment of the invention, the conductive medium comprises a conductive polymer, a carbon-based material or another conductive inorganic material.

According to one embodiment of the invention, the conductive medium comprises a fluid. The conductive medium preferably comprises a molten salt, an ionic liquid or a liquid with a redox addition.

According to one embodiment of the invention, the substrate is conductive. The substrate preferably comprises a metal, a carbon-based material, a semiconductor or a conductive composite material.

• - 1: eine schematische Ansicht eines in der Erfindung verwendeten Substrats und Glaselements,
• - 2: eine schematische Darstellung eines Schritts des Herstellungsverfahrens der erfindungsgemäßen Glaselektrode,
• - 3: eine erfindungsgemäße Glaselektrode,
• - 4: eine alternative Ausführungsform der erfindungsgemäße Glaselektrode,
• - 5: eine alternative Ausführungsform der erfindungsgemäße Glaselektrode,
• - 6: eine alternative Ausführungsform der erfindungsgemäße Glaselektrode.

The invention is explained in more detail on the basis of the following description of the figures. Show it:

• - 1 : a schematic view of a substrate and glass element used in the invention,
• - 2 : a schematic representation of a step in the manufacturing process of the glass electrode according to the invention,
• - 3rd : a glass electrode according to the invention,
• - 4th : an alternative embodiment of the glass electrode according to the invention,
• - 5 : an alternative embodiment of the glass electrode according to the invention,
• - 6th : an alternative embodiment of the glass electrode according to the invention.

1 shows a substrate 10 with a first substrate area 11 and an opposing second substrate surface 12th as well as a glass element 20th with a first glass surface 21 and an opposing second glass surface 22nd . The first substrate surface 11 and the second glass surface 22nd are preferably complementary. This means that the first substrate area 11 and the second glass surface 22nd are designed and shaped such that a maximum surface area of at least one of the two surfaces 11 , 22nd the other face 11 , 22nd touched.

The first substrate surface 11 and the second glass surface 22nd are preferably parallel surfaces. The first substrate surface 11 and the second glass surface 22nd are preferably parallel planar surfaces. Planar surfaces have the advantage that they are easy to bond.

The first substrate surface 11 and the second glass surface 22nd preferably have an average roughness of less than 50 nm. The first substrate surface is particularly preferred 11 and the second glass surface 22nd an average roughness less than 10 nm. The advantage of a low mean roughness is that the two surfaces are bonded 11 , 22nd is made easier.

The first substrate surface 11 should be smooth. The substrate 10 can be multi-component or in relation to the chemical surface composition of the first substrate surface 11 (or doping in semiconductors) be structured.

The glass element 20th preferably contains lithium or sodium. In one embodiment, the glass element contains 20th Lithium silicate. The advantage of lithium or sodium is that the glass has conductivity and pH selectivity.

The glass element 20th preferably has a thickness less than 1000 μm. The thickness of the glass element 20th is through the first glass surface 21 and the second glass surface 22nd Are defined. The glass element preferably has 20th a thickness between 1 µm and 500 µm. The glass element particularly preferably has 20th a thickness between 10 µm and 100 µm. The small thickness of the glass element 20th enables simple miniaturization of the glass electrode 1 for an electrochemical ion-sensitive sensor. It is thus possible to design the electrochemical ion-sensitive sensor in a particularly space-saving manner.

3rd shows a schematic representation of a glass electrode 1 for an electrochemical ion-sensitive sensor. The substrate 10 is with the first substrate surface 11 with the second glass surface 22nd of the glass element 20th connected to each other by bonding.

One channel 13th extends from the first substrate surface 11 to the second substrate surface 12th . More precisely, the channel enables 13th contacting the second glass surface 22nd through the substrate 10 through. The channel 13th is already in the substrate before bonding, for example 10 available. In this case the channel is 13th for example a through hole in the substrate 10 . Alternatively, the channel 13th after bonding into the substrate 10 incorporated. On the training of the canal 13th will be discussed in detail later.

The channel 13th is in 3rd with a fluid conductive medium 2 filled. A lead electrode 3rd is with the conductive medium 2 in electrical contact. For example, the lead electrode 3rd into the fluid 2 submerged. The lead electrode 3rd is made of Ag / AgCI, for example.

The fluid conductive medium 2 out 3rd is for example an electrolyte, for example potassium chloride solution, a molten salt, an ionic liquid or a liquid with a redox addition. In other embodiments, which will be discussed later, the conductive medium 2 , 2 ' , 2 " also comprise another, for example solid, material.

4th shows how 3rd an embodiment of the glass electrode 1 . In contrast to the glass electrode 1 of 3rd is the conductive medium 2 ' the glass electrode 1 of 4th however firmly. Preferably the medium is conductive 2 ' a conductive polymer, carbon-based material, or other conductive inorganic material. The conductive medium can also comprise at least one filler.

Here, too, is the lead electrode 3rd is with the conductive medium 2 ' in electrical contact. For example, the lead electrode 3rd on the conductive medium 2 ' pressed or is with the conductive medium 2 ' firmly connected.

5 shows how 3rd and 4th an embodiment of the glass electrode 1 . In contrast to the glass electrode 1 of 3rd and 4th exhibits the substrate 10 however several channels 13th on. In contrast to the glass electrode 1 of 3rd and 4th is the conductive medium 2 " the glass electrode 1 of 4th but a metal. Preferably the medium is conductive 2 " a coin metal, particularly preferably comprises the conductive medium 2 " Copper or silver. The embodiment described above can of course also have several channels 13th exhibit.

Here, too, is the lead electrode 3rd is with the conductive medium 2 " in electrical contact. For example, the lead electrode 3rd on the conductive medium 2 " pressed or is with the conductive medium 2 " firmly connected.

6th Figure 3 shows an alternative embodiment of the glass electrode 1 . In this embodiment, the glass electrode 1 no channel 13th on. Rather, it is the lead electrode 3rd directly with the substrate 10 in electrical contact. For example, the lead electrode 3rd on the substrate 10 pressed or is with the substrate 10 firmly connected.

The lead electrode 3rd is preferably with the second substrate surface 12th of the substrate 10 in electrical contact.

The following is the procedure for making a glass electrode 1 for an electrochemical ion-sensitive sensor.

As in 1 First, the substrate is shown 10 with the first substrate surface 11 and the opposite second substrate surface 12th , the glass element 20th with the first glass surface 21 and the opposite second glass surface 22nd , as well as the electrical contacting unit 4th provided.

According to one embodiment, the channel is located 13th at a specified position in the substrate 10 . The channel 13th extends from the first substrate surface 11 to the second substrate surface 12th . The channel 13th is for example by a material removing process in the substrate 10 created. Known methods are used to remove material used, for example a chemical material removal process such as etching or a mechanical material removal such as cutting material removal processes, such as drilling. The channel 13th is for example a through hole.

According to an alternative embodiment, a substrate 10 without a channel 13th provided.

In an optional step, the first substrate surface 11 as well as the second glass surface 22nd polished so that the two surfaces are very smooth, ie have an average roughness less than 50 nm. For the polishing, for example, a known polishing method is used. Alternatively, such a smooth surface can also be produced by other methods, such as, for example, drawing, etching.

In an optional step, the glass element 20th and the substrate 10 before placing the two panels on top of each other 10 , 20th cleaned. For example, alcohol is used for cleaning.

As in 2 next, the first substrate surface is shown 11 and the second glass surface 22nd on top of each other. The substrate 10 and the glass element 20th are so with their faces 11 , 22nd placed one on top of the other so that no air between the two panels 10 , 20th is.

In a further step the substrate 10 and the glass element 20th heated to a predetermined temperature. The temperature is preferably lower than the glass transformation temperature of the glass element 20th . Preferably the glass element 20th heated so that the glass element 20th gets a predetermined viscosity. The temperature at which the glass element 20th is heated, for example, between 200 ° C and 500 ° C, preferably between 300 ° C and 400 ° C. The heating takes place, for example, by means of a laser, for example an infrared laser or a so-called hot plate. It is of course also possible to use other known methods for heating the substrate 10 and the glass element 20th to use.

The next step, as in 2 shown, an electrical voltage U to the substrate 10 and the glass element 20th created. Preferably the tension U to the second substrate surface 12th and the first glass surface 21 created. The glass element 20th preferably serves as the cathode and the substrate 10 preferably serves as an anode. So it is attached to the glass element 20th a negative voltage and to the substrate 10 a positive voltage is applied. By applying the electrical voltage U become the first substrate surface 11 and the second glass surface 22nd connected to one another by bonding, more precisely anodic bonding. The electrical voltage is, for example, less than 5kV. For example, the electrical voltage is between 100V and 1000V. The electrical voltage is preferably between 200 and 500 V. While an electrical voltage is applied to the glass element 20th and the substrate 10 is applied, the ion mobility in the glass element 20th which is increased by the temperature and a direction of movement is specified by the polarization. At an interface between the second glass surface 22nd and the first substrate area 11 a bonding process takes place.

If at the beginning of the procedure a substrate 10 without a channel 13th provided or no channel 13th at the beginning in the substrate 10 was formed, so in one embodiment the channel 13th after bonding the substrate 10 with the glass element 20th in the substrate 10 be formed. For this purpose, the above-described material-removing methods are preferably used.

The advantage of forming a canal 13th in the substrate 10 either before the bonding step or after the bonding step is that as the material for the substrate 10 a material can be used which is not conductive at room temperature. Because the channel 13th with a conductive material 2 , 2 ' , 2 " is filled, the substrate must 10 be non-conductive at the temperatures of an approved application area, for example between -60 ° C and 150 ° C.

Alternatively to the step of forming the channel 13th can focus on forming the channel 13th can be dispensed with when the substrate 10 comprises a conductive material. This means that the material of the substrate 10 is conductive at the temperatures of the permitted area of use (for example between -60 ° C and 150 ° C).

In a further step, the canal 13th with a conductive medium 2 , 2 ' , 2 " filled. As described above, various electrically conductive materials or fluids can be used for this.

Then the conductive medium 2 , 2 ' , 2 " or the substrate 10 from the lead electrode 3rd contacted. If as a conductive medium 2 ' , 2 " If a solid material has been selected, then in the step of making contact with the conductive medium 2 ' , 2 " through the lead electrode 3rd , the conductive medium 2 ' , 2 " be melted. This step can also be performed before the step of filling the canal 13th through a conductive medium 2 , 2 ' , 2 " respectively.

In the in 6th The embodiment shown was in the substrate 10 no channel 13th educated. In this embodiment, after the step of applying an electrical voltage to the substrate 10 and to the glass element 20th a step of contacting the substrate 10 with the working electrode 3rd carried out. In this case the lead electrode is 3rd with the substrate 10 in electrical contact. For example, the lead electrode 3rd on the substrate 10 , for example on the first substrate surface 11 , pressed or is with the substrate 10 , or with the first substrate surface 11 firmly connected.

List of reference symbols

1

Glass electrode

2, 2 ', 2' '

conductive medium

3

Lead electrode

4th

Contacting unit

10

Substrate

11

first substrate area

12th

second substrate area

13th

channel

20th

Glass element

21

first glass surface

22nd

second glass surface

U

electrical voltage

Claims (17)

Method for producing a glass electrode (1) for an electrochemical ion-sensitive sensor comprising: - Provision of a substrate (10) with a first substrate surface (11) and an opposing second substrate surface (12), a glass element (20) with a first glass surface (21) and an opposing second glass surface (22), and an electrical contacting unit (4) ), wherein the substrate (10) is electrically conductive, - Laying the first substrate surface (11) and the second glass surface (22) on top of one another, - heating the substrate (10) and the glass element (20) to a predetermined temperature, the predetermined temperature being lower than a glass transformation temperature of the glass element (20), - applying an electrical voltage (U) to the substrate (10) and the glass element (20), so that the first substrate surface (11) and the second glass surface (22) are connected to one another by bonding, - Contacting the substrate (10) with a discharge electrode (3). Method for producing a glass electrode (1) for an electrochemical ion-sensitive sensor comprising: - Provision of a substrate (10) with a first substrate surface (11) and an opposing second substrate surface (12), a glass element (20) with a first glass surface (21) and an opposing second glass surface (22), and an electrical contacting unit (4) ), wherein in the substrate (10) at least one channel (13) located at a fixed position extends from the first substrate surface (11) to the second substrate surface (12), - Laying the first substrate surface (11) and the second glass surface (22) on top of one another, - heating the substrate (10) and the glass element (20) to a predetermined temperature, the predetermined temperature being lower than a glass transformation temperature of the glass element (20), - applying an electrical voltage (U) to the second substrate surface (12) and the first glass surface (21), so that the first substrate surface (11) and the second glass surface (22) are connected to one another by bonding, - Filling the channel (13) with an electrically conductive medium (2, 2 ', 2 "), - Contacting the electrically conductive medium (2, 2 ', 2 ") with a discharge electrode (3). Method for producing a glass electrode (1) for an electrochemical ion-sensitive sensor comprising: - Provision of a substrate (10) with a first substrate surface (11) and an opposing second substrate surface (12), a glass element (20) with a first glass surface (21) and an opposing second glass surface (22), and an electrical contacting unit (4) ), - Laying the first substrate surface (11) and the second glass surface (22) on top of one another, - heating the substrate (10) and the glass element (20) to a predetermined temperature, the predetermined temperature being lower than a glass transformation temperature of the glass element (20), - applying an electrical voltage (U) to the second substrate surface (12) and the first glass surface (21), so that the first substrate surface (11) and the second glass surface (22) are connected to one another by bonding, - Forming a channel (13) in the substrate (10), so that the channel (13) extends from the first substrate surface (11) to the second substrate surface (12), - Filling the channel (13) with an electrically conductive medium (2, 2 ', 2 "), - Contacting the electrically conductive medium (2, 2 ', 2 ") with a discharge electrode (3). Method according to one of the preceding claims, wherein the first substrate surface (11) and the second glass surface (22) have a medium roughness less than 50 nm, preferably less than 10 nm. Procedure according to Claim 4 wherein the mean roughness is achieved by a step of polishing the first substrate surface (11) and the second glass surface (22). Method according to one of the preceding claims, wherein the first substrate surface (11) and the second glass surface (22) are parallel surfaces, preferably are parallel planar surfaces. Method according to one of the preceding claims, wherein the applied electrical voltage (U) is less than 5 kV, preferably between 100 V and 1000 V, particularly preferably between 200 V and 500V. Method according to one of the preceding claims, wherein a negative voltage is applied to the first glass surface (21) and a positive voltage is applied to the second substrate surface (12). Method according to one of the preceding claims, wherein the predetermined temperature is lower than the transformation temperature of the glass element, preferably the predetermined temperature is between 200 ° C and 500 ° C. Glass electrode (1) for an electrochemical ion-sensitive sensor comprising: - A substrate (10) with a first substrate surface (11) and an opposite second substrate surface (12), - A glass element (20) with a first glass surface (21) and an opposing second glass surface (22), the first substrate surface (11) and the second glass surface (22) being connected to one another by bonding, a discharge electrode (3) being connected to the The substrate (10) is in electrical contact. Glass electrode (1) for an electrochemical ion-sensitive sensor comprising: - A substrate (10) with a first substrate surface (11) and an opposite second substrate surface (12), a channel (13) extending in the substrate (10) from the first substrate surface (11) to the second substrate surface (12), - A glass element (20) with a first glass surface (21) and an opposite second glass surface (22), the first substrate surface (11) and the second glass surface (22) being connected to one another by bonding, the channel (13) having a conductive medium (2, 2 ', 2 ") is filled and a discharge electrode (3) is in electrical contact with the conductive medium (2, 2', 2"). Glass electrode (1) according to Claim 10 or 11 wherein the glass element (20) comprises lithium or sodium. Glass electrode (1) according to one of the Claims 10 to 12th wherein the glass element (20) has a thickness less than 1000 μm, preferably a thickness between 1 μm and 500 μm, particularly preferably a thickness between 10 μm and 100 μm. Glass electrode (1) according to one of the Claims 10 to 13th , wherein the conductive medium (2 ″) comprises a metal, preferably comprises a coin metal, particularly preferably comprises copper or silver. Glass electrode (1) according to one of the Claims 10 to 13th wherein the conductive medium (2 ') comprises a conductive polymer, a carbon-based material or another conductive inorganic material. Glass electrode (1) according to one of the Claims 10 to 13th , wherein the conductive medium (2) comprises a fluid, preferably comprises a molten salt, an ionic liquid or a liquid with a redox addition. Glass electrode (1) according to one of the Claims 10 to 16 wherein the substrate (10) is conductive, wherein the substrate (10) preferably comprises a metal, a carbon-based material, a semiconductor or a conductive composite material.

Images