KR20210039656A - Flexible capacitive humidity sensor including porous material - Google Patents

Abstract

The present invention relates to a capacitive sensor. More particularly, the present invention relates to a capacitive sensor including a porous member. According to the present invention, provided is a capacitive sensor including a porous member, which comprises: a flexible substrate; a lower electrode; an upper electrode; and a moisture-sensitive unit which is interposed between the upper electrode and the lower electrode and can absorb moisture. At least one among the upper electrode, the lower electrode, and the moisture-sensitive unit includes a porous member. By the above configuration, the capacity of a humidity sensor is increased, it is possible to sense even at a small value, and there is an effect of facilitating the deformation of the overall shape. In addition, by enabling heating as well as sensing, there is an effect of increasing the reactivity and preventing heat from being transferred to the outside of the sensor.

Description

Flexible capacitive humidity sensor including porous material

The present invention relates to a capacitive sensor, and more particularly, to a capacitive sensor including a porous member.

In general, a humidity sensor measures humidity by using the inherent physical properties of water molecules or water vapor, and by measuring changes in the physical properties of the material by adsorbing water molecules onto a hygroscopic material. Among them, capacitive sensors have been widely used because of their thin, thin-film structure, high environmental resistance, high reliability of measurement values, and reasonable manufacturing costs.

However, the conventional capacitive humidity sensor has a complex structure, which makes it difficult to manufacture in large quantities due to strict management of the capacitance value.The amount of change in capacitance is small, resulting in a large error due to a small change in capacitance, and the amount of change in capacitance is small. Since it is easily affected by the dispersion or temperature characteristics of the circuit, there is a disadvantage that caution is required when selecting a circuit part.

In order to solve the problem of such a conventional capacitive humidity sensor, the prior art illustrated in FIG. 15 has increased the reactivity of the humidity sensor by arranging electrodes on the upper and lower portions of a thin polymeric desiccant, and forming a large number of holes in the upper electrode. . However, even if a hole is formed in the electrode, there is a disadvantage in that the reaction rate of the device is slow because the passage through which the moisture-containing air flows into the desiccant is still narrow. In addition, the rate at which moisture escapes from the dehumidifying agent was slow, so it took more than a few seconds to return to its original state, resulting in poor efficiency.

The present invention was conceived to solve the above problems, and an object of the present invention is to increase the capacity of the humidity sensor by applying a low-density porous member as a material for the upper electrode, the humidity sensor, and the lower electrode, and to enable sensing even at a small value. It is possible to provide a capacitive sensor including a porous member that is easily deformable in its entire shape.

In more detail, the upper electrode, the humidity sensor, and the lower electrode are configured in the form of nanofibers and arranged up and down, or each nanofiber is mixed, or a humidity sensor is made of double nanofibers in which a humidity sensor is inserted inside the nanofibers for electrodes. It is to provide a capacitive sensor including a porous member that increases the capacity of and enables sensing even at a small value.

In addition, it is to provide a capacitive sensor including a porous member that increases reactivity by drawing out at least one pair of terminals capable of receiving power to the outside of the upper electrode and the lower electrode to enable sensing as well as heating.

In addition, it is to provide a capacitive sensor including a porous member that prevents heat from being transferred to the outside of the sensor by forming a groove on the substrate.

The capacitive sensor including the porous member of the present invention is a substrate made of a flexible material, a lower electrode disposed on the substrate, an upper electrode disposed on the lower electrode, and sandwiched between the upper electrode and the lower electrode. And moisture-sensitive nanofibers to which moisture can be adsorbed, and at least one of the upper electrode and the lower electrode is formed of a porous member to increase a contact area between the moisture-sensitive nanofiber and the outside air containing moisture. .

Also, the upper electrode is a conductive nanofiber, and the lower electrode is a conductive film.

In addition, both the upper electrode and the lower electrode are characterized in that the conductive nanofibers.

In addition, the upper electrode is a conductive film in which a plurality of holes are formed on a surface, and the lower electrode is a conductive film.

In addition, it includes a substrate made of a flexible material, a lower electrode disposed on the substrate, an upper electrode disposed on the lower electrode, and moisture-sensitive nanofibers positioned in the same phase as the upper electrode and capable of adsorbing moisture, and the At least one of the upper electrode and the lower electrode is formed of a porous member to increase a contact area between the moisture-sensitive nanofiber and the outside air containing moisture.

In addition, the upper electrode is a conductive nanofiber, the lower electrode is a conductive film, and the conductive nanofiber of the upper electrode and the moisture sensitive nanofiber are mixed to form one layer.

In addition, it characterized in that it further comprises an insulating film between the lower electrode, the moisture-sensitive portion and the upper electrode.

In addition, it is characterized in that a moisture-sensitive nanofiber is additionally included between the lower electrode, the moisture-sensitive portion, and the upper electrode.

In addition, the lower electrode is a conductive film, the upper electrode is a conductive nanofiber, and the upper electrode and the moisture sensitive nanofiber are in the form of a double nanofiber in which the conductive nanofiber is inserted into the moisture sensitive nanofiber. do.

In addition, at least one pair of lower electrode terminals for applying power to the lower electrode is formed by being drawn out of the substrate.

In addition, a groove is formed in a position surrounding the lower electrode from the upper surface of the substrate.

In addition, it is characterized in that the heat dissipation material is filled in the groove.

In addition, it is characterized in that the groove is in a vacuum state.

In addition, at least one pair of upper electrode terminals for applying power to the upper electrode is formed by being drawn out of the substrate.

The capacitive sensor including the porous member of the present invention having the above configuration increases the capacity of the humidity sensor and enables sensing even at a small value by applying a low-density porous member as a material for the upper electrode, the humidity sensor, and the lower electrode. It has the effect of facilitating deformation of the entire shape.

In more detail, the upper electrode, the humidity sensor, and the lower electrode are configured in the form of nanofibers and arranged up and down, or each nanofiber is mixed, or a humidity sensor is made of double nanofibers in which a humidity sensor is inserted inside the nanofibers for electrodes. There is an effect of increasing the capacity of the device and enabling sensing even at a small value.

In addition, by drawing out at least one pair of terminals through which electric power can be applied to the outside of the upper electrode and the lower electrode, not only sensing but also heating, there is an effect of enhancing reactivity.

In addition, there is an effect of preventing heat from being transferred to the outside of the sensor by forming a groove on the substrate.

1 is a schematic diagram showing side surfaces of a lower electrode, an upper electrode, and a humidity sensor according to a first embodiment of the present invention.
FIG. 2 is a schematic diagram showing side surfaces of a lower electrode, an upper electrode, and a humidity sensor according to a second embodiment of the present invention.
3 is a schematic diagram showing side surfaces of a lower electrode, an upper electrode, and a humidity sensor according to a third embodiment of the present invention.
4 is a schematic diagram showing side surfaces of a lower electrode, an upper electrode, and a humidity sensor according to a fourth embodiment of the present invention.
5 is a schematic diagram showing the upper surfaces of a lower electrode, an upper electrode, and a humidity sensor according to a fifth embodiment of the present invention.
6 is a cross-sectional view of a double nanofiber constituting an upper electrode and a humidity sensor in a fifth embodiment of the present invention.
7 is a conceptual diagram showing a manufacturing method of a fifth embodiment of the present invention.
8 is a schematic diagram showing side surfaces of a lower electrode, an upper electrode, and a humidity sensor according to a sixth embodiment of the present invention.
9 is a schematic diagram showing upper surfaces of a lower electrode and a lower electrode terminal of the present invention.
10 is a schematic diagram showing a connection relationship between a lower electrode and a substrate according to the present invention.
11 is a side view of several pairs of lower electrode terminals according to the present invention.
12 is a side view showing several pairs of lower electrode terminals and upper electrode terminals according to the present invention.
13 is a representative diagram of the prior art.

Hereinafter, the technical idea of the present invention will be described in more detail using the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventors appropriately explain the concept of terms in order to explain their own invention in the best way. Based on the principle that it can be defined, it should be interpreted as a meaning and concept consistent with the technical idea of the present invention.

Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention, and do not represent all the technical ideas of the present invention, so that they can be replaced at the time of the present application. It should be understood that there may be various variations.

Hereinafter, the technical idea of the present invention will be described in more detail using the accompanying drawings. The accompanying drawings are only an example illustrated to describe the technical idea of the present invention in more detail, so the technical idea of the present invention is not limited to the form of the accompanying drawings.

The capacitive sensor including the porous member of the present invention may include a substrate made of a flexible material. The substrate 100 may be made of silicon, and it is preferable that the substrate 100 be made of a material that is not a conductor but is easily deformed. In addition, the capacitive sensor 1000 including the porous member of the present invention includes a lower electrode 200 disposed on the substrate 100, an upper electrode 300 disposed on the lower electrode 200, and It is interposed between the lower electrode 200 and the upper electrode 300 and may include a moisture-reducing unit 400 through which moisture can be adsorbed.

In particular, it is preferable that at least one of the lower electrode 200, the upper electrode 200, and the humidity sensor 400 is a porous member. Accordingly, it is possible to propose a capacitive humidity sensor that is flexible and has high sensing performance, and based on the conventional formula that capacitance C is proportional to the contact area A and inversely proportional to the distance d, the error is maximized by maximizing the capacitance. It is possible to propose a capacitive humidity sensor that has the effect of reducing the value.

Hereinafter, the first to fifth embodiments of the present invention will be described. In the first to fifth embodiments of the present invention, one of the upper electrode 300 and the lower electrode 200 is formed of nanofibers. In addition, it is preferable that the nanofibers are closely entangled to form one electrode layer. In addition, the nanofibers at this time are preferably made of a conductive material because they must perform the role of an electrode. Accordingly, the density of the layer of the upper electrode 300 or the lower electrode 200 is greatly reduced, and a large number of large and small irregular holes are formed, thereby making it easier to enter and exit the outside air. In addition, it is preferable that a dehumidifying agent to be in contact with the outside air is disposed between the upper electrode 300 and the lower electrode 200, and the dehumidifying agent at this time is preferably a moisture-sensitive nanofiber 400. When the desiccant is present in the form of the moisture-sensitive nanofiber 400, the density of the desiccant layer is greatly reduced, and a large number of large and small irregular holes are formed, thereby making it easier to enter the outside air. That is, the contact area between the moisture-sensitive nanofiber 400 and the outside air containing moisture can be effectively increased. In addition, since the nanofibers are entangled, the shape of the entire electrode layer can be easily changed, and thus can be applied to a wearable device.

[Example 1]

Hereinafter, a first embodiment of a capacitive sensor 1000 including a porous member will be described with reference to FIG. 1.

The first embodiment of the capacitive sensor 1000 including a porous member discloses that the upper electrode 300 may be made of a conductive nanofiber, and the lower electrode 200 may be made of a conductive film. In particular, it is preferable that the moisture-sensitive nanofibers 400 at this time are entangled with the moisture-sensitive nanofibers in the same manner as the upper electrode 300 to form one layer. In the case where the desiccant layer is formed of the moisture-sensitive nanofibers 400, as the contact area with the outside air increases, the reaction speed may be accelerated because the outside air is easily penetrated and absorbed between the moisture-sensitive nanofibers. In addition, moisture can quickly escape from the moisture-sensitive nanofiber 400, so that it can be easily returned to its original state after sensing. In addition, by forming the upper electrode 300 and the desiccant layer in a form in which nanofibers are entangled, it is possible to increase stability by absorbing an external shock.

[Example 2]

Hereinafter, a second embodiment of the capacitive sensor 1000 including a porous member will be described with reference to FIG. 2.

The second embodiment of the capacitive sensor 1000 including a porous member discloses that both the upper electrode 300 and the lower electrode 200 may be formed of conductive nanofibers. In the second embodiment, if the moisture-sensitive nanofiber 400 is damaged, both can contact the outside air, so that the contact area with the outside air increases, and the outside air is easily penetrated and absorbed into the moisture-sensitive nanofiber 400, so that the reaction speed is increased. It can be faster. In addition, moisture can quickly escape from the moisture-sensitive nanofiber 400, so that it can be easily returned to its original state after sensing. In addition, by forming the upper electrode 300 and the humidity sensor 400 in a form in which nanofibers are entangled, it is possible to increase stability by absorbing an external shock.

In the second embodiment of the present invention, unlike the first embodiment described above, both the upper electrode 300 and the lower electrode 200 are formed of nanofibers. In the second embodiment, the density of the upper electrode 300 or the lower electrode layer is significantly reduced compared to the case of the first embodiment in which only one of the upper electrode 300 and the lower electrode 200 is formed of nanofibers, and there are many large and small irregular holes. By being formed, outside air can be easily accessed. That is, since the humidity sensor 400 can vertically contact the outside air containing moisture, the sensitivity of the sensor can be effectively increased. In addition, since all configurations except for the substrate 100 are configured by entangled nanofibers, the shape of the entire electrode layer is very easy to change, so that it can be applied to a wearable device.

[Examples 3 and 4]

Hereinafter, third to fourth embodiments of the capacitive sensor 1000 including a porous member will be described with reference to FIGS. 3 to 4.

In the third to fourth embodiments of the capacitive sensor 1000 including a porous member, the lower electrode 200 is made of a conductive film, the upper electrode 300 is made of a conductive nanofiber, and a moisture sensitive nanofiber ( It is disclosed that 400 and the upper electrode 300 may be disposed on the upper surface of the lower electrode 200 by being positioned at the same phase. In more detail, the humidity sensor of the present invention has a layered structure including a plurality of layers, and in the third and fourth embodiments, the upper electrode 300 and the moisture sensitive nanofiber 400 are located on the same layer. Yes.

In this case, it is preferable that the conductive nanofibers constituting the moisture-sensitive nanofiber 400 and the upper electrode 300 are formed like a single nanofiber by two strands of nanofibers being struck. This is to maximize the contact area between the moisture sensitive nanofiber 400 and the upper electrode 300.

In the case of the third embodiment, the insulating layer 500 is applied in the form of a film between the lower electrode 200 and the moisture sensor 400 and the upper electrode, and in the fourth embodiment, the lower electrode 200 and the moisture sensor ( 400) and an additional thin layer of moisture-sensitive nanofibers between the upper electrodes.

In the third to fourth embodiments, unlike the first and second embodiments described above, the moisture sensitive nanofiber 400 and the upper electrode 300 are mixed and entangled. Accordingly, the conductive nanofiber and the moisture sensitive nanofiber 400 are intertwined. As the contact area increases significantly and the distance decreases, the capacitance can increase significantly compared to conventional sensors. Accordingly, it is possible to correct a high error rate, and there is an effect that mass production is possible because the management of the capacitance value is not strict. In addition, it does not require great attention when selecting a circuit part, so it can have high utilization.

In addition, although only the case where the lower electrode 200 is a conductive film is illustrated in FIGS. 3 to 4, the lower electrode 200 may be a conductive nanofiber or a conductive film. When the lower electrode 200 is a conductive nanofiber, the sensitivity of the sensor may be increased by allowing the outside air to contact the lower surface of the moisture sensitive nanofiber 400 and the upper electrode 300 as well. On the other hand, when the lower electrode 200 is a conductive film, the connection between the moisture-sensitive nanofiber 400 and the substrate 100 can be more firmly supported, thereby increasing the durability of the sensor.

[Example 5]

Hereinafter, a fifth embodiment of the capacitive sensor 1000 including a porous member will be described with reference to FIGS. 5 to 7.

In the fifth embodiment of the capacitive sensor 1000 including a porous member, the upper electrode 300 and the moisture sensitive nanofiber 400 are formed in the form of a double nanofiber in which a conductive member is inserted into the moisture sensitive nanofiber, and the lower electrode It discloses that it can be disposed on the upper surface of the 200. This is illustrated in FIG. 5. Referring to FIG. 6, it can be seen that the outer surface of the double nanofiber is a moisture-reducing agent, and the inside is a conductive member. This is to increase the sensing sensitivity by increasing the contact area with the outside air by exposing the dehumidifying agent to the outside. It is to increase the contact area between the 400 and the upper electrode 300 and reduce the distance to an extreme to maximize the capacitance, thereby adding ease of use to the sensor. In this case, the insulating layer 500 may be applied in the form of a film between the double nanofibers and the lower electrode 200.

In addition, although FIG. 5 shows only the case where the lower electrode 200 is a conductive film, the lower electrode 200 may be a conductive nanofiber or a conductive film. When the lower electrode 200 is a conductive nanofiber, the sensitivity of the sensor may be increased by allowing the outside air to contact the lower surface of the moisture sensitive nanofiber 400 and the upper electrode 300 as well. On the other hand, when the lower electrode 200 is a conductive film, the connection between the moisture sensitive nanofiber 400 and the substrate 100 can be more firmly supported, thereby increasing the durability of the sensor, and the upper electrode in the form of a conductive nanofiber ( 300) can increase the contact area.

In order to manufacture the above-described double nanofibers, a dual-structure electrospinning nozzle 600 including an electrode solution insertion portion 610, a desiccant solution insertion portion 620, and a solution outlet 630 may be used. This dual structure electrospinning nozzle 600 is preferably used as shown in FIG. 7. The manufacturing method of the capacitive sensor 1000 including the porous member shown in FIG. 7 is such that when the material is compressed at one side of the cylinder and the material is extruded to the other side of the cylinder, the material is molded into a fiber form using electrospinning. It is to do. This is a technique commonly used when manufacturing nanofibers, but in the case of the present invention, since it is to manufacture double nanofibers, as described above, the electrode solution insertion portion 610 and the desiccant solution insertion portion 620 have two solution insertion portions. It is characterized by including a dual-structure electrospinning nozzle 600 having two separate spaces inside the cylinder.

In the fifth embodiment, unlike the above-described embodiments, the humidity sensor 400 and the upper electrode 300 are integrally formed, and accordingly, the contact area between the humidity sensor 400 and the upper electrode 300 is higher and the distance is 0. As it decreases to converge to, the capacitance value can be maximized. Accordingly, a high error rate can be more easily corrected, and since the management of the capacitance value is not strict, there is an effect that mass production is possible. In addition, it does not require great attention when selecting a circuit part, so it can have high utilization.

[Example 6]

Hereinafter, a sixth embodiment of a capacitive sensor 1000 including a porous member will be described with reference to FIG. 8.

The sixth embodiment of the capacitive sensor 1000 including the porous member of the present invention discloses that at least one of the upper electrode 300 and the lower electrode 200 may be formed as a porous electrode. At this time, the density of the porous electrode is very low, and thus, outside air can easily contact the moisture-sensitive nanofiber 400 through the upper electrode 300 or the lower electrode 200.

In addition, although FIG. 8 shows only the case where the upper electrode 300 is a porous electrode and the lower electrode 200 is a conductive film, both the upper electrode 300 and the lower electrode 200 may be porous electrodes. When both the upper electrode and the lower electrode 200 are porous electrodes, the sensitivity of the sensor may be increased by allowing the outside air to vertically contact the moisture sensitive nanofibers 400. On the other hand, when only one of the upper electrode 300 and the lower electrode 200 is a porous electrode (in this case, it is more preferable that the upper electrode 300 is a porous electrode.) The upper electrode 300 and the lower electrode ( 200) and the moisture-sensitive nanofiber 400, the connection between the substrate 100 can be supported more firmly, it is possible to increase the durability of the sensor.

Hereinafter, a case in which the moisture sensitive agent in contact with the upper electrode 300 and the lower electrode 200 is a moisture sensitive film other than the moisture sensitive nanofiber 400 will be described.

[Example 7]

In the seventh embodiment of the capacitive sensor 1000 including a porous member, the upper electrode 200 is in contact with the substrate 100 and the upper electrode 300 is in contact with the outside air. When composed of nanofibers, the contact area between the moisture-sensitive film and the outside air can be effectively increased. In addition, by forming the upper electrode 300 in a form in which nanofibers are entangled, in addition to its role as an electrode, it is possible to absorb an external shock to some extent. Accordingly, it is possible to minimize the impact to the moisture-sensitive film located under the upper electrode 300 and the lower electrode 200.

According to the seventh embodiment, since the moisture-sensitive film and the outside air are easily contacted in the moisture-sensitive film between the conductive nanofibers, the contact area increases, and thus, the outside air is easily penetrated and absorbed, so that the reaction speed may be increased. In addition, moisture can quickly escape from the dehumidifying agent, making it easier to return to the original state after sensing.

[Example 8]

The eighth embodiment of the capacitive sensor 1000 including a porous member discloses that both the upper electrode 300 and the lower electrode 200 may be formed of conductive nanofibers. At this time, since both the upper electrode 300 and the lower electrode 200 are made of nanofibers, the durability of the entire humidity sensor may be weakened. As the moisture sensitive film is sandwiched between the upper electrode 300 and the lower electrode 200, it may also serve to support the connection between the upper electrode 300 and the lower electrode 200. According to the eighth embodiment, since the moisture-sensitive film and the outside air are easily contacted by the moisture-sensitive film between the conductive nanofibers, the contact area increases, and thus, the outside air is easily penetrated and absorbed, so that the reaction speed may be increased. In addition, moisture can quickly escape from the dehumidifying agent, making it easier to return to the original state after sensing. In addition, since the upper electrode 300 and the humidity sensor 400 are formed in a form in which nanofibers are entangled, it is possible to increase stability by absorbing an external shock.

In the eighth embodiment of the present invention, unlike the seventh embodiment described above, both the upper electrode 300 and the lower electrode 200 are formed of nanofibers. In the eighth embodiment, the density of the upper electrode 300 or the lower electrode layer is significantly reduced compared to the case of the seventh embodiment in which only one of the upper electrode 300 and the lower electrode 200 is formed of nanofibers, and there are many large and small irregular holes. By being formed, outside air can be easily accessed. That is, since the moisture-sensitive film can vertically contact the outside air containing moisture, the sensitivity of the sensor can be effectively increased. In addition, since most of the configurations are composed of entangled nanofibers, the shape of the entire electrode layer can be easily transformed, thereby increasing applicability to wearable devices.

[Example 9]

The ninth embodiment of the capacitive sensor 1000 including a porous member discloses that a moisture sensitive nanofiber is separately added in addition to the moisture sensitive film, so that the upper electrode 300 and the moisture sensitive agent can be contacted separately. In more detail, it is disclosed that the upper electrode 300 is made of conductive nanofibers, and the upper electrode 300 is mixed with moisture-sensitive nanofibers made of a dehumidifying agent to form one layer, so that it can be disposed on the upper surface of the lower electrode 200 do. In particular, it is preferable that the nanofibers constituting the moisture-sensitive film and the upper electrode 300 are entangled so that the two strands of nanofibers are tangled in the same shape.

Additionally, the lower electrode 200 may be a conductive nanofiber or a conductive film. When the lower electrode 200 is a conductive nanofiber, the sensitivity of the sensor may be increased by allowing the outside air to vertically contact the moisture-sensitive film. On the other hand, when the lower electrode 200 is a conductive film, the connection between the moisture-sensitive film and the substrate 100 may be more firmly supported, thereby increasing the durability of the sensor.

In the ninth embodiment, unlike the seventh and eighth embodiments described above, the moisture sensitive part 400 and the upper electrode 300 are mixed and entangled. Accordingly, the contact area between the conductive nanofiber and the moisture sensitive nanofiber is greatly increased and the distance is reduced. Thus, the capacitance can be significantly increased compared to the conventional sensor. Accordingly, it is possible to correct a high error rate, and there is an effect that mass production is possible because the management of the capacitance value is not strict. In addition, it does not require great attention when selecting a circuit part, so it can have high utilization.

[Example 10]

The tenth embodiment of the capacitive sensor 1000 including the porous member of the present invention discloses that at least one of the upper electrode 300 and the lower electrode 200 may be formed as a porous electrode. At this time, the density of the porous electrode is very low, and thus, outside air can easily contact the moisture-sensitive film through the upper electrode 300 or the lower electrode 200.

Additionally, both the upper electrode 300 and the lower electrode 200 may be porous electrodes. When both the upper electrode and the lower electrode 200 are porous electrodes, the sensitivity of the sensor may be increased by allowing the outside air to contact the moisture-sensitive film vertically. On the other hand, when only one of the upper electrode 300 and the lower electrode 200 is a porous electrode (in this case, it is more preferable that the upper electrode 300 is a porous electrode.) The upper electrode 300 and the lower electrode ( 200) and the moisture-sensitive film, the connection between the substrate 100 can be supported more firmly, it is possible to increase the durability of the sensor.

In addition, there may be a number of embodiments regarding the number and arrangement of terminals formed on the lower electrode 200 and the upper electrode 300. Hereinafter, an embodiment of the lower electrode 200 and the upper electrode 300, the shape of the substrate and the connection relationship between the lower electrode 200 and the upper electrode 300 will be described with reference to FIGS. 9 to 12.

The lower electrode terminal 210 is present in the lower electrode 200 by being drawn out of the substrate 100, and the lower electrode terminal 210 is connected to an external power source so that power may be applied to the lower electrode 200. One or more pairs of the lower electrode terminals 210 may exist. In particular, it is preferable that one pair of the lower electrode terminals 210 receive power for sensing, and it is preferable that all pairs of the lower electrode terminals 210 including the lower electrode terminal 210 receive power for heating the lower electrode 200. . That is, any of the pair of lower electrode terminals 210 may receive power for sensing and may receive power for heating the lower electrode 200.

In this case, it is preferable that the pair of lower electrode terminals 210 for heating the lower electrode 200 surround the lower electrode 200 and face each other in addition to the position shown in FIG. 9. Accordingly, the lower electrode 200 may be heated evenly. In addition, the lower electrode terminal 210 may be a nanofiber polymer, and may have a flat plate shape. As the electrode is heated in this way, the reactivity of the capacitive sensor 1000 including the porous member may be increased.

In addition, the upper electrode terminal 310 is present in the upper electrode 300 by being drawn out of the substrate 100, and the upper electrode terminal 310 is connected to an external power source so that power can be applied to the upper electrode 300. have. One or more pairs of the upper electrode terminals 310 may exist. In particular, it is preferable that one pair of the upper electrode terminals 310 receive power for sensing, and it is preferable that all upper electrode terminals 310 pairs including the same receive power for heating the upper electrode 300. . That is, any of the pair of upper electrode terminals 310 may receive power for sensing and may receive power for heating the upper electrode 300.

In this case, it is preferable that the pair of upper electrode terminals 310 for heating the upper electrode 300 surround the upper electrode 300 and be disposed to face each other. Accordingly, the upper electrode 300 may be heated evenly. In addition, the upper electrode terminal 310 may be a nanofiber polymer, and may have a flat plate shape. As the electrode is heated in this way, the reactivity of the capacitive sensor 1000 including the porous member may be increased.

Referring to FIG. 10, a groove 110 may be formed in the substrate 100 at a position surrounding the lower electrode 200 except for a position corresponding to the lower electrode terminal 210. 11 is a side view when a plurality of lower electrode terminals 210 are drawn out, and FIG. 12 is a side view when a plurality of upper electrode terminals 310 are also drawn out. The groove 110 may be filled with a heat dissipating material, or a vacuum state may be maintained. Since the groove 110 is formed, it is possible to prevent heat from being transferred to the outside of the sensor, and to minimize the influence on circuits other than the sensor.

In a method of forming a vacuum in the groove 110, it is preferable to first perform a groove formation pattern trench etching, then oxidize and fill the trench, deposit an oxide film, and form a hole for vacuum groove etching. Then, it is preferable to etch the substrate 100 to form a vacuum groove in the same reactor (Chamber) and deposit for vacuum groove sealing. The vacuum at this time is not an absolute vacuum and may be a vacuum of tens to several hundred mTorr.

The above method is a method for forming a vacuum groove on a silicon substrate using a MEMS process, and if the MEMS process is not performed, trench etching is performed to form a vacuum groove, and groove sealing is performed in a vacuum reaction furnace. It is desirable to proceed to.

As described above, in the present invention, specific matters such as specific elements, etc., and limited embodiments have been described, but this is provided only to help a more general understanding of the present invention, and the present invention is limited to the above one embodiment. It is not, and a person of ordinary skill in the field to which the present invention belongs can make various modifications and variations from this description.

Therefore, the spirit of the present invention is limited to the described embodiments and should not be determined, and all things that have equivalent or equivalent modifications to the claims as well as the claims to be described later belong to the scope of the spirit of the present invention. .

1000: Capacitive sensor including a porous member
100: substrate
110: home
200: lower electrode
210: lower electrode terminal
300: upper electrode
310: upper electrode terminal
400: moisture-sensitive nanofiber
500: insulating layer
600: dual structure electrospinning nozzle
610: electrode solution insertion part
620: desiccant solution insertion part
630: solution outlet

Claims (14)

Board;
A lower electrode disposed on the upper surface of the substrate;
An upper electrode disposed on the lower electrode;
A moisture-sensitive nanofiber sandwiched between the upper electrode and the lower electrode and capable of adsorbing moisture;
And at least one of the upper electrode and the lower electrode is formed of a porous member to increase a contact area between the moisture-sensitive nanofiber and the outside air containing moisture.
The method of claim 1,
The upper electrode is a conductive nanofiber,
Capacitive sensor including a porous member, characterized in that the lower electrode is a conductive film.
The method of claim 1,
The capacitive sensor including a porous member, characterized in that both the upper electrode and the lower electrode are conductive nanofibers.
The method of claim 1,
The upper electrode is a conductive film having a plurality of holes formed on the surface thereof,
The lower electrode is a capacitive sensor including a porous member, characterized in that the conductive film.
Board;
A lower electrode disposed on the upper surface of the substrate;
An upper electrode disposed on the lower electrode;
Moisture-sensitive nanofibers positioned in the same phase as the upper electrode and capable of adsorbing moisture;
And at least one of the upper electrode and the lower electrode is formed of a porous member to increase a contact area between the moisture-sensitive nanofiber and the outside air containing moisture.
The method of claim 5,
The upper electrode is a conductive nanofiber,
The lower electrode is a conductive film,
Capacitive sensor including a porous member, characterized in that the conductive nanofibers of the upper electrode and the moisture sensitive nanofibers are mixed to form one layer.
The method of claim 6,
Capacitive sensor including a porous member, characterized in that it further comprises an insulating film between the lower electrode and the moisture-sensitive portion and the upper electrode.
The method of claim 6,
A capacitive sensor including a porous member, characterized in that the lower electrode, the moisture sensitive nanofibers are further included between the moisture sensitive portion and the upper electrode.
The method of claim 5,
The lower electrode is a conductive film,
The upper electrode is a conductive nanofiber,
The upper electrode and the moisture-sensitive nanofiber is a capacitive sensor including a porous member, characterized in that the form of a double nanofiber in which the conductive nanofiber is inserted into the moisture-sensitive nanofiber.
The method according to claim 1 or 5,
A capacitive sensor including a porous member, characterized in that at least one pair of lower electrode terminals for applying power to the lower electrode is formed by being drawn out of the substrate.
The method of claim 10,
The substrate is formed wider than the lower electrode, the capacitive sensor including a porous member in which a groove is formed with a predetermined thickness on a surface to which the lower electrode is not attached.
The method of claim 11,
Capacitive sensor including a porous member, characterized in that the heat dissipation material is filled in the groove.
The method of claim 11,
Capacitive sensor including a porous member, characterized in that the groove is in a vacuum state.
The method according to claim 1 or 5,
A capacitive sensor including a porous member, characterized in that at least one pair of upper electrode terminals for applying power to the upper electrode is formed by being drawn out of the substrate.

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