JP6666139B2 - Thermometer - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a temperature measuring element in which an inner-layer resistance wiring is provided between a plurality of insulating layers stacked on each other.

  2. Description of the Related Art As a sensor (temperature measuring element) for detecting a temperature of a fluid having a high temperature (for example, about several hundred to 1,000 ° C.) such as an exhaust gas, a sensor utilizing a change in electric resistance of a metal material with temperature is known. As the metal material, a metal material containing platinum is often used from the viewpoints of oxidation resistance at a high temperature and temperature dependency of a resistance value.

  As a sensor containing a metal material, for example, as described in Patent Document 1, a platinum thin film provided with a resistance pattern is formed on the surface of a heat-resistant insulating substrate made of a ceramic sintered body such as alumina, and a terminal is provided. There is known a temperature sensor element having a configuration in which a lead terminal such as a platinum wire is welded to an electrode.

JP-A-11-112214

  The sensor is used by applying a current from a lead terminal to use a change in electric resistance. At this time, a large potential difference may be generated between metal materials such as terminal electrodes provided on the surface of the insulating base. Migration of the metal material occurs due to the generated potential difference, and a large fluctuation or short circuit of the electric resistance value between the electrodes or the resistance patterns causes a failure of the sensor.

Temperature detector of one embodiment of the present invention includes a rectangular plate-like insulating substrate in which a plurality of insulating layers are laminated, said one main surface of the insulating base, two corners adjacent to each other with an Hotan sides A first electrode and a second electrode provided in each of the portions, a lead connected to each of the first electrode and the second electrode, and an internal resistance wiring provided between layers of an insulating layer of the insulating base. , provided in the interlayer of the one main surface side, a first interconnection connected to the first electrode, provided in the interlayer of the other hand the main surface side, which is connected to the first wiring and the second electrode An internal resistance wiring having two wirings, and a long side region extending along a long side from a region where the first electrode is provided on one main surface of the insulating base and connected to the first wiring; and a first surface wiring, is connected to each of the first electrode and the second electrode Wherein characterized Rukoto comprising a second covering member covering the first cover member and at least the first surface wiring large volume covering the lead was.

  According to the temperature measuring element of one embodiment of the present invention, the distance between the second electrode and the first surface wiring can be increased, and the migration generated between the second electrode and the first surface wiring can be reduced. Therefore, even when used for a long time, it is possible to obtain a highly reliable temperature measuring element with few failures.

(A) And (b) is a perspective view which shows the temperature measuring element of embodiment of this invention. It is a top view of a temperature measuring body. It is a top view of the temperature measuring element which is another embodiment. It is a perspective view of the temperature measuring body in which the protection member was provided. It is a perspective view of the temperature measuring body in which the protection member was provided.

  A temperature detector according to an embodiment of the present invention will be described with reference to the accompanying drawings. The distinction between the upper and lower parts in the following description is for convenience, and does not limit the upper and lower parts when a wiring board or the like is actually used.

  FIG. 1 is a perspective view showing a temperature measuring element according to an embodiment of the present invention. FIG. 1A is an external perspective view of a temperature measuring element, and FIG. 1B is an exploded perspective view of the temperature measuring element. FIG. 2 is a plan view of the temperature measuring element. In FIG. 2, the protective glass 5 is not shown so that the one main surface 2a of the insulating base 2 can be easily understood.

  The temperature measuring element 1 includes an insulating substrate 2, leads 3, 4, protective glass 5, a first electrode 6, a second electrode 7, a first wiring 10 as an internal resistance wiring, a second wiring 11 as an internal resistance wiring, It has one surface wiring 20. Temperature measurement is performed using the fact that the electric resistance of the first wiring 10 and the second wiring 11 changes according to the environmental temperature. That is, the environmental temperature at which the temperature measuring element 1 is located is calculated and detected from the measured values of the electrical resistance of the first wiring 10 and the second wiring 11.

  The insulating base 2 is a rectangular plate having one main surface 2a and the other main surface 2b, and is a base portion for providing internal resistance wiring. The insulating substrate 2 is formed of a ceramic sintered body such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, and a glass ceramic sintered body. The insulating base 2 is formed by laminating a plurality of insulating layers (eight layers in the example shown in FIG. 1) made of such a ceramic sintered body.

  The insulating substrate 2 can be manufactured by the following method, for example, when each insulating layer is made of an aluminum oxide sintered body. First, a slurry prepared by adding and mixing an appropriate organic binder and a solvent to raw material powders such as aluminum oxide, silicon oxide, magnesium oxide and calcium oxide is formed into a sheet shape by a doctor blade method or the like to form a ceramic green sheet. Make it. Next, after cutting these ceramic green sheets into appropriate dimensions, a plurality of these sheets are laminated to form a laminate. Thereafter, the laminated body is fired at a high temperature (about 1600 ° C.) to manufacture the insulating base 2. Each of the plurality of ceramic green sheets becomes an insulating layer.

  On one main surface 2 a of the insulating base 2, two surface terminal electrodes, that is, a first electrode 6 and a second electrode 7 are provided. The first electrode 6 and the second electrode 7 join the leads 3 and 4 for connecting to an external circuit to the insulating base 2 and electrically connect the leads 3 and 4 to the internal resistance wiring.

  One main surface 2a of the insulating base 2 is rectangular, and has four sides of two short sides 2a1 and 2a2 parallel to each other and two long sides 2a3 and 2a4 parallel to each other. The first electrode 6 and the second electrode 7 are provided at two corners of the one main surface 2a with one short side 2a1 interposed therebetween.

  For example, in FIG. 2, two short sides 2a1 and 2a2 are parallel to the paper surface in the vertical direction, and two long sides 2a3 and 2a4 are parallel to the paper surface in the horizontal direction. The first electrode 6 and the second electrode 7 are provided at respective corners vertically sandwiching the one short side 2a1 on the right side of the paper surface, and the first electrode 6 is provided at a lower corner portion of the paper surface, The second electrode 7 is provided at a corner above the paper surface.

An internal resistance wiring composed of a first wiring 10 and a second wiring 11 is provided between layers of the insulating base 2. The first wiring 10 is a wiring provided between layers on the one main surface 2 a side of the insulating base 2, that is, a wiring closer to the first electrode 6 and the second electrode 7, and is connected to the first electrode 6. . The second wiring 11 is a wiring provided between layers on the other main surface 2 b side of the insulating base 2, that is, a wiring remote from the first electrode 6 and the second electrode 7, and is connected to the second electrode 7. .

  The internal resistance wiring composed of the first wiring 10 and the second wiring 11 is formed of platinum, which is a metal material whose electric resistance changes according to temperature, or a metal material containing platinum as a main component. In order to detect a change in the electrical resistance of the metal material according to the temperature according to the temperature change, it is preferable that the absolute value of the electrical resistance of the metal material in the initial stage (for example, about 25 ° C., so-called normal temperature) is larger.

  This is for the following reasons. That is, the change of the electric resistance according to the temperature change of the internal resistance wiring occurs at a fixed ratio regardless of the magnitude (absolute value) of the initial electric resistance. That is, the larger the value of the initial electric resistance, the larger the absolute value of the change in the electric resistance due to the temperature change. The greater the absolute value of the change in electrical resistance, the less likely it is to be affected by noise (fluctuations in electrical resistance due to factors other than temperature changes). Also, the measurement becomes easier. Therefore, it is preferable that the internal resistance wiring has a large initial electric resistance. Therefore, a metal material such as platinum is formed in a linear shape, the length of the section for measuring the electric resistance is long, and this is an effective form for increasing the absolute value of the electric resistance.

  Regarding components other than platinum in the metal material containing platinum as a main component, the components (types) and addition amounts thereof are appropriately adjusted for the purpose of adjusting the temperature resistance coefficient (TCR) of the internal resistance wiring and improving the heat resistance. Selected. Examples of the component other than platinum include a metal material of a platinum group element such as palladium, rhodium, and iridium, and gold. For example, when importance is placed on the linearity of the change in the electrical resistance with respect to the change in the temperature of the internal resistance wiring, it is preferable that the platinum content is large.

  The metal material containing platinum as a main component contains platinum at a ratio of about 80% by mass or more. Platinum and other components may form an alloy, and may exist as independent crystal grains. The internal resistance wiring may include an additive other than the metal component such as platinum or a metal material containing platinum as a main component. Examples of the additive include inorganic particles similar to those contained in the insulating base 2 such as aluminum oxide. The additive is added, for example, to match the firing shrinkage of the internal resistance wiring and the insulating layer.

  The internal resistance wiring is formed by, for example, applying a metal paste prepared by kneading a powder of platinum together with an organic solvent and a binder on a main surface or the like of a ceramic green sheet serving as an insulating layer in a predetermined pattern and simultaneously firing the metal paste. Can be.

  The electric resistance between one end of the internal resistance wiring and the other end is measured by, for example, an external electric circuit. The measured electric resistance changes according to the temperature of the internal resistance wiring, and the temperature of the internal resistance wiring changes according to the temperature of the environment where the temperature sensor 1 is located (external temperature). That is, the external temperature is detected by measuring the electric resistance of the internal resistance wiring.

  The external temperature detected by the temperature measuring element 1 is, for example, the temperature of various kinds of combustion exhaust gas, and it may be necessary to detect a high temperature of about several hundred to 1,000 ° C. The internal resistance wiring is made of platinum or a metal material containing platinum as a main component because of such good high-temperature stability and good linearity of the electrical resistance change according to the temperature. For example, the temperature measuring element 1 is mounted on an external board (not shown) including an electric circuit (external electric circuit) for resistance detection as described above, and an object to be measured exists along with such an external board and the like. It is mounted on the part (gas flow path etc.).

  In addition, if the internal resistance wiring is exposed to the outside air, it is unnecessary for destruction or deformation due to adhesion of foreign matter or erroneous collision with the external substrate or other components mounted on the external substrate. There is a possibility that the electric resistance changes. In order to prevent this, the internal resistance wiring is provided between a plurality of insulating layers. In other words, the internal resistance wiring is provided inside the insulating base 2 and is not exposed outside.

  In the present embodiment, the internal resistance wiring is composed of two wirings: a first wiring 10 disposed on one main surface 2a side and a second wiring 11 disposed on the other main surface 2b side. The first wiring 10 may be provided between one insulating layer and may be provided between a plurality of adjacent layers. In the case where the wiring is provided between a plurality of layers, the wiring provided between the layers is electrically connected to each other by a via conductor which is a through conductor penetrating the insulating layer in the thickness direction. Similarly to the first wiring 10, the second wiring 11 may be provided between one insulating layer, may be provided between a plurality of layers adjacent to each other, or may be provided between a plurality of layers. Wirings provided between the layers are electrically connected by via conductors. Further, the first wiring 10 and the second wiring 11 are also connected by via conductors.

  The via conductor is formed of, for example, a conductor material (metal material) mainly containing the same metal material (platinum or the like) as the internal resistance wiring. Examples of such a metal material include platinum or a material containing platinum as a main component and an inorganic filler such as alumina. The inorganic filler is used, for example, when the via conductor and the insulating substrate 2 are formed by simultaneous firing, to match the shrinkage ratio and shrinkage behavior of the two.

  Via conductors can be formed, for example, by filling platinum metal paste similar to that for forming internal resistance wiring into through holes provided in advance in ceramic green sheets serving as insulating layers, and firing them simultaneously. it can. The through-hole can be provided in the ceramic green sheet by a processing method such as a mechanical drilling process using a metal pin or a drilling process using a laser beam. In this case, particles of the inorganic filler as described above may be added to the metal paste.

  Leads 3 and 4 are connected to the first electrode 6 and the second electrode 7, respectively. In the present embodiment, for example, the lead 4 is connected to the first electrode 6, and the lead 3 is connected to the second electrode 7.

  The first electrode 6 and the second electrode 7 can be formed by the same method using, for example, the same metal material (eg, platinum) as the internal resistance wiring. The first electrode 6 and the second electrode 7 of the present embodiment have a rounded rectangular pattern made of platinum, but may have other shapes.

  Since the first electrode 6 and the second electrode 7 may be placed in a high-temperature environment, the first electrode 6 and the second electrode 7 are made of a metal material having high oxidation resistance at a high temperature, such as platinum group metal including platinum or gold. Is preferred.

  In the present embodiment, a protective glass 5 is provided on one main surface 2a of the insulating base 2 so as to cover a connection portion between the first electrode 6, the second electrode 7, and the leads 3 and 4.

  The protective glass 5 is made of, for example, non-alkali crystallized glass or the like, and can be manufactured by the following method.

  First, a slurry prepared by adding and mixing an appropriate organic binder, a solvent, and the like to the raw material powder is completely covered on the connection portions between the first electrode 6, the second electrode 7, and the leads 3, 4. Supply in excess like a mountain. Next, the insulating substrate 2 containing the slurry is fired and cooled to room temperature, thereby producing the protective glass 5 that completely covers the connection site.

  The temperature measuring element 1 of the present embodiment has a first surface wiring 20 which is a surface wiring provided on one main surface 2a of the insulating base 2. The first surface wiring 20 is provided in the long side region 2c of the one main surface 2a extending along the long side 2a3 from the region where the first electrode 6 is provided.

  In FIG. 2, the first electrode 6 is provided at a lower right corner of the one main surface 2 a toward the paper surface, and the long side region 2 c is a long side connected to the corner where the first electrode 6 is provided. A side, that is, a region extending along the long side 2a3 below the paper surface. The long side region 2c is a region where the first electrode 6 is provided among two regions in which one main surface 2a of the insulating base 2 is bisected by a line parallel to the long sides 2a3 and 2a4. And is located on the other short side 2a2 side of the first electrode 6. The first surface wiring 20 is provided in the long side region 2c. The first surface wiring 20 is arranged relatively close to the first electrode 6, and is arranged relatively far from the second electrode 7.

  Further, the first surface wiring 20 is connected to the first wiring 10 provided on one main surface 2a side among the internal resistance wirings.

  The first electrode 6 and the first surface wiring 20 are both provided on one main surface 2a of the insulating base 2 and are connected to the first wiring 10 disposed on the one main surface 2a side. The first electrode 6 and the first surface wiring 20 are connected to the first wiring 10 immediately below. The first wiring 10 is connected to a second wiring 11 disposed below the first wiring 10 and on the other main surface 2b side. Further, second wiring 11 is connected to second electrode 7 provided on one main surface 2a.

  The first surface wiring 20 is provided, for example, to connect the first wiring 10 to a passive element or the like mounted on the one main surface 2a.

  The first wiring 10 may be, for example, a resistance adjusting wiring. The resistance adjustment wiring is a wiring for adjusting the resistance value of the internal resistance wiring after completing the temperature measurement body 1. In the temperature measuring element 1, the resistance value of the internal resistance wiring may deviate from a target value due to manufacturing variations or the like. In such a case, a resistance adjusting wiring is provided to adjust the resistance value after completion. The first surface wiring 20 is used in combination with the first wiring 10 which is a resistance adjusting wiring. The resistance adjustment wiring is composed of a plurality of wirings having different wiring lengths. The plurality of wirings are connected to the first surface wiring 20 by via conductors, and the wirings are connected by the first surface wiring 20. As shown in FIG. 2, the first surface wiring 20 includes a plurality of adjustment wirings 20a including lands connected to via conductors and connection wirings connecting lands. When the connection wiring is cut by cutting or laser irradiation, the connection between the wirings in the resistance adjustment wiring is cut. Thereby, the entire length of the resistance adjustment wiring is reduced, and the resistance value of the resistance adjustment wiring is reduced. Since the resistance value of the internal resistance wiring is the sum of the resistance value of the first wiring 10 and the resistance value of the second wiring 11 connected in series to the first wiring 10, the resistance value of the first wiring As the resistance value decreases, the resistance value of the internal resistance wiring decreases. Thus, by changing the number of cuts of the adjustment wiring 20a, it is possible to appropriately change the resistance value of the internal resistance wiring.

The second wiring 11 may be any wiring as long as a predetermined resistance value can be obtained. However, in order to reduce the thickness of the insulating base 2 and downsize the temperature measuring body 1, It is preferable to increase the resistance value of the wiring provided between one layer and reduce the number of stacked insulating layers. In order to increase the resistance value of the conductor wiring provided between one layer, for example, a plurality of straight portions arranged in parallel with each other and a plurality of straight portions connecting ends of adjacent straight portions among the plurality of straight portions are connected. It is preferable to use a meandering wiring having a folded portion. The folded portion connects the ends of a plurality of adjacent linear portions to each other. In other words, the plurality of straight portions and the plurality of folded portions are sequentially connected in series to form one meandering pattern (meandering pattern).

  When the second wiring 11 has a meandering pattern, relatively long conductor wirings are sequentially folded and arranged between layers, which is advantageous in providing as long a conductor wiring as possible between one layer. When the length of the conductor wiring is longer, the electric resistance of the second wiring 11 can be further increased. That is, for example, since the electric resistance before the temperature measurement (the above-mentioned initial state such as the normal temperature) is relatively large, the absolute value of the change in the electric resistance according to the temperature change is large. For this reason, accurate temperature measurement can be easily performed from the room temperature to the high temperature range of about 1,000 ° C. or the like.

  Further, for example, as shown in FIGS. 1 and 2, when the insulating base 2 is rectangular and the wiring conductor is meandering, the linear part and the folded part of the meandering wiring conductor are formed of an insulating layer. The following effects can be obtained if they are arranged parallel to each side. That is, in this case, the distance from each side of the insulating layer to the wiring conductor closest to the side is made substantially the same in each of the linear portion and the folded portion. Therefore, in each of the straight portion and the folded portion, there is a possibility that the distance from the outer peripheral portion of the insulating base 2 to the wiring conductor is partially extremely short, and the platinum of the wiring conductor is easily sublimated to the outside. Reduced.

  Further, in this case, the width of the relatively wide portion between the straight portion and the folded portion is approximately the same, and furthermore, the gap between each side of the insulating layer and each of the straight portion and the folded portion is different. The distance may be the same. In this case, the distance from the outer periphery to the wiring conductor is made substantially the same over substantially the entire periphery of the insulating layer. Therefore, the possibility of promoting sublimation of platinum to the outside in a part of the length direction of the wiring conductor can be further reduced.

Such a wiring conductor has almost the same overall shape as that between the layers of the rectangular insulating layer. Therefore, the temperature measuring element 1 can improve the temperature measurement accuracy and long-term reliability of the internal resistance wiring. When importance is placed on the second wiring 11, it is preferable that the second wiring 11 has a meandering shape, and the straight portion and the folded portion are arranged in parallel with the outer periphery of the insulating layer.

  As a current path of the temperature measuring element 1, the current flows from the lead 4 through the first electrode 6, the first wiring 10, a part of the current flowing to the first surface wiring 20, and the rest to the second wiring 11. The current flowing through the second wiring 11 returns from the vicinity of the lowermost layer to the one main surface 2 a by the via conductor, and flows through the lead 3 via the second electrode 7.

  According to such a current path, the potential difference between the first electrode 6 and the second electrode 7 provided on the same one main surface 2a is the highest, and the potential difference between the first surface wiring 20 and the second electrode 7 is also the same. Next high. Migration between the metal materials forming the conductor is likely to occur between the conductors where such a high potential difference occurs.

  The protective glass 5 having a relatively large volume exists between the first electrode 6 and the second electrode 7, and passes through the surface of the protective glass 5 between the first electrode 6 and the second electrode 7. The migration distance of the metal material becomes longer. Therefore, a short circuit due to metal migration is less likely to occur than a portion covered with glass thinly, such as the first surface wiring.

  The greater the distance between the first surface wiring 20 and the second electrode 7, the more the migration can be suppressed. However, considering the distance, it is difficult to secure a wiring space for the first surface wiring 20. In the present embodiment, in order to reduce migration that occurs between the first surface wiring 20 and the second electrode 7, the first surface wiring 20 is placed in the long side region 2 c that is relatively far from the second electrode 7. Provided. With such a long side region 2c, it is possible to suppress the occurrence of migration while securing a wiring space for the first surface wiring.

  For example, if the coating member (overcoat glass) is a non-alkali crystallized glass with a potential difference of 2 V, an environmental temperature of 1000 ° C., and an alkali-free crystallized glass, generally, if the distance between the two electrode terminals is 400 μm or more, migration can be effectively performed. Can be reduced. The temperature measuring element 1 of the present embodiment has a size of 2 mm × 4 mm in a plan view, and if the first surface wiring 20 is provided in the long side region 2c, the distance between the first surface wiring 20 and the second electrode 7 is 400 mm. ８００800 μm, and an effect of reducing migration can be obtained.

  By reducing the occurrence of migration, the thermometer 1 of the present embodiment can be a highly reliable thermometer 1 with few failures even when used for a long time.

  FIG. 3 is a plan view of a temperature measuring element according to another embodiment. The thermometer 1A of the present embodiment is different from the above-described embodiment in that a second surface wiring 21 is further provided in addition to the first surface wiring 20 as the surface wiring. The configuration other than the second surface wiring 21 is the same as that of the above-described embodiment, and therefore, the same configuration is denoted by the same reference numeral as in the above-described embodiment, and detailed description is omitted. The second surface wiring 21 is connected to the long side region 2c on one main surface 2a of the insulating base 2 and extends to the short side region 2d extending along the short side 2a2 which is the other short side opposite to the short side 2a1. The wiring is provided, and is connected to the first wiring 10 like the first surface wiring 20.

  The short side region 2 d is located at a position relatively distant from the second electrode 7. When the second surface wiring 21 is provided in the short side region 2 d, the short side region 2 d is located between the second electrode 7 and the second surface 7. In this case, the occurrence of migration can be reduced. In addition, since the surface layer wiring can be provided not only in the long side region 2c but also in the short side region 2d, the wiring space for the surface layer wiring is widened and more surface layer wiring is provided on the one main surface 2a of the insulating base 2. Can be.

  Also in the present embodiment, for example, the first wiring 10 may be a wiring for connecting a passive element or the like mounted on the one main surface 2a, or may be a resistance adjusting wiring.

  Further, the temperature measuring elements 1 and 1A of the present embodiment may be provided with covering members 8 and 9 that cover the first surface wiring 20 and the second surface wiring 21. 4 and 5 are perspective views of a temperature measuring body provided with a protection member.

  As shown in FIG. 2, the temperature sensor 1 has a first surface wiring 20 provided on a long side region 2 c of the one main surface 2 a of the insulating base 2. In order to protect the first surface layer wiring 20, a rectangular covering member 8 made of, for example, a glass material is provided so as to cover the entire long side region 2c.

  Further, as shown in FIG. 3, the temperature measuring element 1A has a first surface wiring 20 and a second surface wiring 21 provided on the long side region 2c and the short side region 2d of the one main surface 2a of the insulating base 2, respectively. I have. In order to protect the first surface wiring 20 and the second surface wiring 21, an L-shaped covering member 9 made of, for example, a glass material is provided so as to cover the entire long side region 2c and short side region 2d.

  As described above, when the first wiring 10 is a wiring for resistance adjustment, if a part of the first surface wiring 20 is cut off at the time of use or the like after the resistance adjustment, the resistance value of the internal wiring conductor is adjusted after the adjustment. And deviates from the target value. In order to reduce such a shift in the resistance value, a covering member 8 that covers the first surface wiring 20 is provided. The same applies to the second surface wiring 21, and the covering member 9 that covers the second surface wiring 21 is provided.

Since the temperature measuring element 1 is used under a high temperature environment of 1000 ° C. or more, a resin material or the like cannot be used as a material of the covering member. By using a glass material, the first surface wiring 20 and the second surface wiring 21 can be sufficiently protected even in a high temperature environment.

  The glass material constituting the covering members 8 and 9 is made of, for example, non-alkali crystallized glass.

1, 1A: temperature measuring element 2: insulating base 2a: one main surface 2b: other main surface 2c: long side region 2d: short side region 3, 4: lead 5 Protective glass 6 First electrode 7 Second electrode 8 Covering member 9 Covering member 10 First wiring 11 Second wiring 20 First surface wiring 20a Adjustment wiring 21 Second surface wiring 2a1, 2a2 Short side 2a3, 2a4 Long side

Claims (4)

A rectangular plate-shaped insulating base formed by laminating a plurality of insulating layers,
A first electrode and a second electrode provided at two corners adjacent to each other across one short side of one main surface of the insulating base;
A lead connected to each of the first electrode and the second electrode;
An internal resistance wiring provided between layers of the insulating layer of the insulating base, wherein the first resistance is provided between the one main surface side layer and is connected to the first electrode and the other main surface side layer. An internal resistance wiring provided and having a second wiring connected to the first wiring and the second electrode;
A first surface wiring provided on a long side region extending along a long side from a region where the first electrode is provided on one main surface of the insulating base, and connected to the first wiring;
A temperature measuring element comprising: a first covering member having a large volume covering the lead connected to each of the first electrode and the second electrode; and a second covering member covering at least the first surface wiring. .   A second surface layer provided in a short side region of the one main surface of the insulating base, which is connected to the long side region and extends along the other short side opposite to the one short side, and connected to the first wiring; The thermometer according to claim 1, further comprising a wiring. It said second cover member is made of a glass material, further temperature sensing element according to claim 2, wherein the benzalkonium to cover the second surface wiring.   The second wiring is a meandering wiring having a plurality of straight portions arranged in parallel with each other and a plurality of folded portions connecting ends of adjacent straight portions among the plurality of straight portions. The temperature sensor according to any one of claims 1 to 3, wherein