JP2008107166A - Humidity sensor and manufacturing method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a humidity sensor having a simple constitution and detecting a relative humidity in the atmosphere, and to provide its manufacturing method. <P>SOLUTION: The humidity sensor 1 is provided with a humidity sensitive section 24 having a humidity sensitive film 23 for changing the electrostatic capacitance by adsorbing the moisture, and comb electrodes 22a, 22b covered with the humidity sensitive film 23 and detecting a change in the electrostatic capacitance; a circuit element section 25 for processing an output signal from the humidity sensitive section 24; and a pad 26 electrically connected to a bonding wire 31, and outputting an output signal from the circuit element section 25 to the outside of the humidity sensor 1. The humidity sensitive section 24, the circuit element section 25 and the pad 26 are mounted on the same semiconductor substrate 21, and the connection between the pad 26 and the bonding wire 31 is protected by, and covered with a pod protective film 27. The pod protective film 27 is integrally formed with the humidity sensitive film 23, by using the same material as the humidity sensitive film 23. The entire upper surface of the semiconductor substrate 21 is covered with the humidity sensitive film 23 and the pod protective film 27. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a humidity sensor for detecting the humidity of the atmosphere surrounding the humidity sensor and a method for manufacturing the same.

As this type of humidity sensor and a method for manufacturing the same, a technique of forming a moisture sensitive film through a dispenser, such as the technique described in Patent Document 1, is conventionally known. That is, in such a humidity sensor, for example, a pair of comb-shaped electrodes (comb electrodes) made of ruthenium oxide are arranged on the same plane on a ceramic substrate so as to be separated from each other. In addition, a substantially square pad made of, for example, aluminum is formed at each end of the comb electrodes. These pads and lead terminals are wire bonded to each other with bonding wires. Furthermore, for example, a so-called dam is formed in which an annular frame member is formed so as to cover the entire circumference of the comb electrode. Then, when forming a moisture sensitive film on the entire inner surface of the frame member of the ceramic substrate, a moisture sensitive agent is dropped from above the substrate toward the full height of the frame member through the dispenser toward the inner side of the frame member of the ceramic substrate, By drying the dripped moisture sensitive agent, a moisture sensitive film is uniformly formed with a predetermined thickness.
JP 2002-71612 A

  According to the above prior art, since the frame member is formed around the entire comb electrode, the humidity detection portion of the humidity sensor becomes large, which leads to an increase in the size of the humidity sensor. Such an increase in size is greatly reflected in the manufacturing cost, and there is a possibility that the humidity sensor cannot be provided at a low cost.

  On the other hand, it is possible to omit the frame member. However, simply omitting the frame member may cause the following problems. That is, when the humidity sensor is mounted on a moving body such as an automobile, it is often exposed to a moisture-containing atmosphere as compared with a case where the humidity sensor is mounted on a consumer device. The pad is easily corroded by moisture contained in the atmosphere. Therefore, when the humidity sensor is mounted on an automobile, a protective gel made of a water-resistant material is generally applied to such a pad and thermally cured after application to suppress corrosion of the pad due to moisture. However, when the protective gel is applied to the pad, the protective gel is accidentally applied to the moisture-sensitive film, or the protective gel flows to the location where the moisture-sensitive film is formed before it is cured. If it adheres to the film, the properties of the moisture sensitive film will change, which may interfere with the humidity detection accuracy of the atmosphere. Therefore, it is difficult to omit the frame member as described above. In other words, a dam structure with a frame member must be adopted. Therefore, the problem of increasing the size of the humidity sensor still remains, and there is room for improvement. Incidentally, in the prior art, since the entire periphery of the moisture sensitive film is surrounded by the frame member, as a result, the adhesion of the protective gel to the moisture sensitive film is reduced.

  In addition, even if such a situation is a resistance type humidity sensor that detects a change in the humidity of the atmosphere as a change in the impedance of the moisture sensitive film, a capacitance type that detects a change in the humidity of the atmosphere as a change in capacitance between a pair of electrodes. Even a humidity sensor can occur in the same way.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a humidity sensor capable of detecting the relative humidity of the atmosphere with a simpler configuration and a method for manufacturing the same.

  In order to achieve such an object, in the invention described in claim 1, a moisture-sensitive film whose physical quantity changes by adsorbing moisture and a pair of electrodes which are covered by the moisture-sensitive film and detect changes in the physical quantity A moisture sensing unit, a circuit element unit for processing an output signal of the moisture sensing unit, and an output signal of the circuit element unit for outputting the output signal of the circuit element unit outside the humidity sensor by being electrically connected to a bonding wire. As a humidity sensor that includes a pad on the same substrate and detects an atmospheric humidity change as a change in the physical quantity, a connection portion of the pad with the bonding wire is formed of the same material as that of the moisture-sensitive film. The pad protection film was covered.

  As described in the problem section, when the humidity sensor is mounted on a moving body such as an automobile, it may be exposed to a moisture-containing atmosphere as compared with a case where the humidity sensor is mounted on a consumer device. Many pads, particularly often made of aluminum, are easily corroded by moisture contained in the atmosphere. Therefore, in the prior art, the pad is covered with a protective gel made of a water-resistant material different from the material for forming the moisture-sensitive film, and corrosion due to moisture is suppressed.

  In that respect, in the configuration described in claim 1, the connection portion of the pad with the bonding wire is covered with a pad protective film made of the same material as that for forming the moisture sensitive film. As a result, even when the pad protective film is accidentally attached to the moisture sensitive film when covering the connection portion of the pad with the bonding wire with the pad protective film, the moisture sensitive film and the pad Since the protective film is made of the same material, the property of the moisture sensitive film hardly changes. Therefore, the atmospheric humidity detection accuracy is hardly disturbed. Moreover, in such a structure, since the dam structure by the frame member which had to be employ | adopted by the prior art becomes unnecessary, this can be omitted. Therefore, the physique of the humidity sensor can be reduced. Further, in such a configuration, the restrictions on the layout on the substrate that are applied to the moisture-sensitive portion, the circuit element portion, and the pad are lifted. As a result, the degree of freedom in design can be improved. Thus, the relative humidity of the atmosphere can be detected with a simpler configuration.

  In the first place, the moisture sensitive film changes the physical quantity by adsorbing moisture contained in the atmosphere. Using the same material as the material for forming the moisture-sensitive film having such properties, it seems that the formation of a pad protective film that should suppress corrosion due to moisture rather promotes corrosion due to moisture. However, although the moisture-sensitive film adsorbs moisture, the amount of adsorbed water is actually small, and it has been confirmed by the inventors that the concern of promoting corrosion due to moisture is eliminated.

  In addition, since the moisture-sensitive film and the pad protective film are formed of the same material, in the configuration according to claim 1, the pad protective film has the moisture-sensitive film as in the invention according to claim 2, for example. The structure is preferably formed integrally with the membrane. Furthermore, in the configuration according to claim 2, the entire surface of the substrate is covered with the moisture-sensitive film and the pad protective film as in the invention according to claim 3, for example. Is desirable. In such a configuration, the moisture-sensitive film and the pad protective film are preferably formed through a dispenser, as in the invention described in claim 4 above. In particular, in the configuration of claim 4, when forming the moisture-sensitive film and the pad protective film through a dispenser, the film thickness can be easily controlled only by adjusting the viscosity of these forming materials. .

  On the other hand, in order to achieve the above object, in the invention described in claim 5, a pair of a moisture-sensitive film whose physical quantity changes by adsorbing moisture and a change in the physical quantity covered by the moisture-sensitive film are detected. A moisture-sensitive part having electrodes, a circuit element part for processing an output signal of the moisture-sensitive part, and an output signal of the circuit element part is output to the outside of the humidity sensor by being electrically connected to a bonding wire And a bonding sensor for the pad, using the same material as the material for forming the moisture-sensitive film, as a method of manufacturing a humidity sensor for detecting humidity change in the atmosphere as a change in the physical quantity. A pad protection film is formed to cover the connection portion.

  As described above, and as described in the problem section, when the humidity sensor is mounted on a moving body such as an automobile, the moisture content is lower than when mounted on a consumer device. Pads that are often exposed to an atmosphere including them, and often composed of aluminum, are easily corroded by moisture contained in the atmosphere. Therefore, in the prior art, the pad is covered with a protective gel made of a water-resistant material different from the material for forming the moisture-sensitive film, and corrosion due to moisture is suppressed.

  In that respect, in the method according to claim 5, the pad protective film that covers the connection portion of the pad with the bonding wire is formed of the same material as that of the moisture sensitive film. As a result, even when the pad protective film is accidentally attached to the moisture sensitive film when covering the connection portion of the pad with the bonding wire with the pad protective film, the moisture sensitive film and the pad Since the protective film is made of the same material, the property of the moisture sensitive film hardly changes. Therefore, the atmospheric humidity detection accuracy is hardly disturbed. Moreover, in such a method, since the dam structure by the frame member employ | adopted by the prior art becomes unnecessary, this can be omitted. Therefore, the physique of the humidity sensor can be reduced. Furthermore, in such a method, restrictions on the board layout concerning the moisture-sensitive part, the circuit element part, and the pad are lifted. As a result, the degree of freedom in design can be improved. Thus, a humidity sensor that can detect the relative humidity of the atmosphere with a simpler configuration can be manufactured.

  The moisture sensitive film originally changes the physical quantity by adsorbing moisture contained in the atmosphere. When the same material as the material for forming the moisture-sensitive film having such properties is used for the pad protective film which should suppress corrosion due to moisture, it seems that corrosion due to moisture is rather promoted. However, although the moisture sensitive film adsorbs moisture, the amount of adsorbed water is actually very small, and it has been confirmed by the inventors that the concern of promoting corrosion due to moisture is eliminated. This is also as described above.

  Further, in order to form the moisture sensitive film and the pad protective film from the same material, in the configuration according to claim 5, for example, as in the invention according to claim 6, the pad protective film is formed as the moisture sensitive film. It is good to form integrally. Furthermore, in the method according to the sixth aspect, it is desirable that the entire surface of the substrate is covered with the moisture-sensitive film and the pad protective film, for example, as in the invention according to the seventh aspect. In such a method, the moisture-sensitive film and the pad protective film may be formed through a dispenser, particularly as in the invention described in claim 8. In particular, in the method of claim 8, when the moisture sensitive film and the pad protective film are formed through a dispenser, the film thickness can be easily controlled only by adjusting the viscosity of these forming materials. .

  Hereinafter, an embodiment of a humidity sensor and a method for manufacturing the same according to the present invention will be described with reference to FIGS. In the humidity sensor of the present embodiment, as will be described in detail below, the connection portion of the pad with the bonding wire is covered with a pad protective film formed of the same material as the moisture-sensitive film forming material. It has a structure. In addition, the humidity sensor of the present embodiment is embodied as a capacitive humidity sensor that detects a change in the humidity of the atmosphere as a change in capacitance between the comb electrodes.

  FIG. 1 is a perspective view of a humidity sensor according to the present embodiment, and FIG. 2 is a side sectional view of the humidity sensor according to the present embodiment. First, the configuration of the humidity sensor according to the present embodiment will be described with reference to FIGS.

  As shown in FIG. 1, the humidity sensor 1 according to the present embodiment basically includes an IC chip 20 having a humidity sensing unit 24, a circuit element unit 25, and the like, which will be described later, and an output of the IC chip 20. The lead terminal 30 for taking out out of the humidity sensor 1 is provided in the case 10 formed, for example, in a bottomed rectangular tube shape.

  Among these, as shown in FIG. 2, the IC chip 20 has an atmosphere surrounding the humidity sensor 1 and a pair of electrodes 22 a and 22 b disposed on the semiconductor substrate 21 made of, for example, silicon so as to be opposed to each other on the same plane. And a humidity sensing portion 24 having a pair of electrodes 22a and 22b and a moisture sensing film 23 covering the electrodes. Further, the IC chip 20 includes a circuit element portion 25 that detects the relative humidity of the atmosphere on the surface layer portion of the semiconductor substrate 21 based on a change in capacitance between the electrodes 22 a and 22 b in the moisture sensitive portion 24. Further, the IC chip 20 is electrically connected to the bonding wire 31 so that the pad 26 for outputting the output signal of the circuit element unit 25 to the outside of the humidity sensor 1 is connected to the pair of electrodes 22a and 22b. Similarly, it is provided on the semiconductor substrate 21.

  In addition, although the shape of a pair of electrode 22a and 22b is not specifically limited, In this Embodiment, the comb-tooth shape is employ | adopted as the shape. As a result, the arrangement area of the moisture-sensitive part 24 can be reduced, and the area where the pair of electrodes 22a and 22b face each other can be increased, and the capacitance between these electrodes that changes as the humidity of the atmosphere changes. The amount of change increases. As a result, the sensitivity of the humidity sensor 1 for detecting humidity is improved. Since the detection principle of such a capacitive humidity sensor is generally known, a detailed description thereof is omitted here.

  On the other hand, as shown in FIG. 1 and FIG. 2, the lead terminals 30 are formed in, for example, a rectangular cross section, and are arranged at a predetermined interval in a plurality (seven in this embodiment) at one end in the case 10. The case 10 is provided so as to penetrate the side wall of the case 10. The plurality of lead terminals 30 are electrically connected to pads 26 made of, for example, aluminum via bonding wires 31. Then, information on the relative humidity of the atmosphere obtained through the circuit element unit 25 is sequentially transmitted as “circuit element unit 25 → pad 26 → bonding wire 31 → lead terminal 30”, and is output to the outside of the humidity sensor 1.

  By the way, when the humidity sensor 1 is mounted on a moving body such as an automobile, for example, it is often exposed to an atmosphere containing moisture as compared with a case where the humidity sensor 1 is mounted on a consumer device. Therefore, since the pad 26 is made of aluminum, it is easily corroded by moisture contained in the atmosphere. Therefore, in the humidity sensor 1 of the present embodiment, as shown in FIG. 1 and FIG. 2, the pad 26 is made of the same material as the moisture-sensitive film 23 on the entire upper surface including the connection portion with the bonding wire 31. The pad protection film 27 is made of. In this way, the pad 26 is prevented from being corroded by moisture contained in the atmosphere. In the present embodiment, as shown in FIGS. 1 and 2, the pad protection film 27 is formed with a predetermined film thickness (for example, “5 μm to 10 μm”) integrally with the moisture sensitive film 23, The entire surface of the semiconductor substrate 21 is covered with the moisture sensitive film 23 and the pad protective film 27 thus integrally formed.

  As described in the Background Art section, in the prior art, generally, the pad is covered with a protective gel made of a water-resistant material different from the material for forming the moisture-sensitive film to suppress corrosion due to moisture. It was. When the protective gel is applied to the pad, the protective gel is accidentally applied to the moisture sensitive film, or the protective gel flows to the location where the moisture sensitive film is formed and adheres to the moisture sensitive film before the curing. If this happens, the properties of the moisture sensitive film will change, and the humidity detection accuracy of the atmosphere will often be hindered.

  However, in the present embodiment, the pad protective film 27 has the same shape as the moisture sensitive film 23 and is integrally formed, so that the pad protective film 27 changes the properties of the moisture sensitive film 23. Such a thing hardly occurs. Therefore, the atmospheric humidity detection accuracy is hardly hindered. Moreover, in such a structure, since the dam structure by the frame member which had to be employed in the prior art becomes unnecessary, this can be omitted, and the size of the humidity sensor 1 can be reduced. Become. Furthermore, in such a configuration, the restrictions on the layout on the semiconductor substrate 21 that are applied to the moisture-sensitive part 24, the circuit element part 25, and the pad 26 are lifted. As a result, the degree of freedom in design can be improved.

  In the first place, the moisture sensitive film 23 changes the capacitance between the comb electrodes 22a and 22b by adsorbing moisture contained in the atmosphere. Using the same material as the material for forming the moisture-sensitive film 23 having such properties, the pad protection film 27 that should suppress corrosion due to moisture is formed, and it seems that corrosion due to moisture is rather promoted. . However, although the moisture sensitive film 23 adsorbs moisture, the amount of moisture adsorbed is actually small. For this reason, the concern of promoting corrosion due to moisture has been eliminated.

  Hereinafter, a method for manufacturing the humidity sensor 1 configured as described above will be described with reference to FIGS. FIG. 3 is a flowchart showing the manufacturing process of the humidity sensor manufacturing method according to the present embodiment, and FIG. 4 is a diagram schematically showing a drip mode of the moisture-sensitive agent in the dispensing process. .

  As shown in FIG. 3, when manufacturing the humidity sensor 1 of the present embodiment, first, the semiconductor substrate 21 is assembled to the case 10 as a process of step S <b> 10. Specifically, the semiconductor substrate 21 on which the moisture sensitive portion 24, the circuit element portion 25, and the pad 26 are already fabricated is assembled at a predetermined position on the bottom of the case 10 where the lead terminals 30 are already formed. Thus, the semiconductor substrate 21 is mechanically fixed to the case 10.

  When such a case assembling process is completed, wire bonding is performed as a process of step S20. That is, the pads 26 on the semiconductor substrate 21 and the portions protruding from the inner wall of the case 10 of the lead terminals 30 are wire-bonded by the bonding wires 31. Thus, the semiconductor substrate 21 is electrically connected to the lead terminal 30.

  Next, as a process of Step S30 and Step S40, the moisture sensitive film 23 and the pad protective film 27 are formed on the upper surface of the semiconductor substrate 21 bonded by wire using the dispenser 40.

  Specifically, as the process of step S30, first, the viscosity of a moisture sensitive agent (for example, polyimide), which is a material for forming the moisture sensitive film 23 and the pad protective film 27, is adjusted in an appropriate facility. The moisture-sensitive agent is stored at a temperature of, for example, “−20 ° C.” or less, and when the moisture-sensitive film 23 or the like is formed, the temperature is raised to room temperature (for example, “20 ° C.”). However, the moisture sensitive agent has a high viscosity at room temperature, and it is difficult to form the moisture sensitive film 23 and the pad protective film 27 through the dispenser 40. Even if it can be formed, it takes a long time. Therefore, it is necessary to reduce the viscosity of the moisture sensitive agent. Therefore, in the present embodiment, after considering the time until it is dropped on the semiconductor substrate 21 through the dispenser 40, the speed of spreading on the semiconductor substrate 21 after being dropped, the film thickness after being cured (imidized), and the like. Then, the moisture sensitive agent is adjusted to a predetermined viscosity. When adjusting the viscosity of such a moisture-sensitive agent, for example, a solvent such as NMP (N-methylpyrodon) is used as a diluent and mixed with the moisture-sensitive agent at a predetermined ratio corresponding to the predetermined viscosity. At this time, the viscosity may be adjusted by controlling the temperature of these solvents together with the mixing of the diluent or in place of the mixing of the diluent. In short, if the moisture sensitive film 23 and the like can be formed on the surface of the semiconductor substrate 21 through the dispenser 40, the viscosity adjustment mode is arbitrary.

  When the viscosity of the moisture-sensitive agent is adjusted in this way, a predetermined amount of the moisture-sensitive agent is dropped at a time from a predetermined position on the semiconductor substrate 21 through the dispenser 40 as a subsequent step S40. The dropping mode at this time is shown in FIG. As shown in FIG. 4, the dispenser 40 is disposed approximately above the center of the semiconductor substrate 21, that is, between the portion where the comb electrodes 21 a and 21 b of the semiconductor substrate 21 are formed and the portion where the pads 26 are formed. From the upper side, a predetermined amount of the moisture sensitive agent is hung at a time toward the upper surface of the semiconductor substrate 21. Since the thus-dropped moisture-sensitive agent has fluidity, it spreads in the form shown in FIG. 4 on the semiconductor substrate 21 and finally the whole semiconductor substrate 21 in the form shown in FIG. It will cover the upper surface. It should be noted that such a dampening amount of the moisture-sensitive agent is such that a predetermined film thickness (for example, “5 μm to 10 μm”) is obtained on the comb electrodes 21 a and 21 b of the semiconductor substrate 21 and the pad 26 of the semiconductor substrate 21. Is set to

  As the subsequent step S50, a curing step is performed. NMP used as a diluent is mixed with the moisture sensitive agent dropped onto the semiconductor substrate 21 through the processes of the previous step S30 and step S40. In order to remove such diluent, the semiconductor substrate 21 is heated for 12 hours at a temperature of about 350 ° C. in an appropriate facility. Accordingly, the diluent is removed from the moisture sensitive agent and cured (imidized) by curing. That is, the moisture sensitive agent dropped on the semiconductor substrate 21 becomes the moisture sensitive film 23 and the pad protective film 27.

  As described above, when the moisture sensitive film 23 and the pad protective film 27 are formed on the semiconductor substrate 21, a cover (not shown) is assembled to the case 10 in the subsequent step S60. That is, a cover provided with a mesh (not shown) for circulating air inside and outside the case 10 is assembled to the opening of the bottomed rectangular tube-shaped case 10 (FIG. 1). Thus, the humidity sensor 1 is manufactured.

  The humidity sensor and the manufacturing method thereof according to the present invention are not limited to the configuration and method exemplified in the above embodiment, and may be implemented as, for example, the following embodiment appropriately modified from the above embodiment. it can.

  In the above embodiment, as the dispensing step (step S40 in FIG. 3), a predetermined amount of moisture-sensing agent is applied once from the upper part of the semiconductor substrate 21 toward the upper surface of the semiconductor substrate 21 through the dispenser 40. I was hanging on. The dropping mode by the dispenser 40 is not limited to this. In addition, as shown in FIG. 5 as a diagram corresponding to FIG. 4, the moisture sensitive agent is divided into a plurality of times (for example, twice) from a predetermined position on the semiconductor substrate 21 through a dispenser 40 by a predetermined amount. It is good also as hanging down. That is, the dispenser 40 drops the moisture-sensitive agent once by a predetermined amount from the upper part of the upper surface of the semiconductor substrate 21 where the comb-tooth electrodes 21a and 21b are formed toward the upper surface of the semiconductor substrate 21. After the dripping, it moves to above the portion where the pad 26 on the upper surface of the semiconductor substrate 21 is formed, and the moisture sensitive agent is dripped once by a predetermined amount. The dampening agent thus dropped has fluidity and spreads on the surface of the semiconductor substrate 21. Further, in this case, as shown in the previous FIG. 2, it is not necessary to drop the moisture sensitive agent through the dispenser 40 so that the moisture sensitive agent covers the entire upper surface of the semiconductor substrate 21. That is, an amount that provides a film thickness of a predetermined thickness (for example, “5 μm to 10 μm”) on at least the comb-tooth electrodes 21 a and 21 b on the upper surface of the semiconductor substrate 21 and the pads 26 on the upper surface of the semiconductor substrate 21. The moisture sensitive agent may be dripped through the dispenser 40.

  In the above embodiment, the moisture sensitive film 23 and the pad protective film 27 are formed through the dispenser 40, but the present invention is not limited to this. In short, as long as the moisture-sensitive film 23 and the pad protective film 27 can be formed from the same forming material so as to cover the entire upper surface of the semiconductor substrate 21, the forming method is not limited to the dispenser 40 and is arbitrary. Further, the moisture sensitive film 23 and the pad protective film 27 may not cover the entire upper surface of the semiconductor substrate 21, and the moisture sensitive film 23 and the pad protective film 27 may not be integrally formed. In short, the moisture sensitive film 23 is formed so as to cover the portion where the comb-tooth electrodes 22a and 22b are formed on the upper surface of the semiconductor substrate 21, and the portion where the pad 26 is formed on the upper surface of the semiconductor substrate 21 is covered. If the pad protection film 27 is formed as described above, the intended purpose can be achieved.

  In the above-described embodiment, the capacitance humidity sensor that detects the humidity change of the atmosphere as the capacitance change between the comb-tooth electrodes 22a and 22b is realized. However, the detection principle is not limited to this. In addition, this may be realized as a resistance humidity sensor that detects a change in the humidity of the atmosphere as a change in the impedance of the moisture sensitive film 23.

The perspective view of one Embodiment of the humidity sensor concerning this Embodiment. Side surface sectional drawing of the humidity sensor of the embodiment. The flowchart which shows the manufacturing process about the manufacturing method of the humidity sensor concerning this Embodiment. The figure which shows typically the dripping aspect of the moisture sensitive agent in the dispensing process of the embodiment. The figure which shows typically the dripping aspect of the moisture sensitive agent in the dispensing process of a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Humidity sensor, 10 ... Case, 20 ... IC chip, 21 ... Semiconductor substrate, 22a, 22b ... Comb-shaped electrode (a pair of electrodes), 23 ... Humidity sensitive film, 24 ... Humidity sensitive part, 25 ... Circuit element part , 26 ... pads, 27 ... pad protective films, 30 ... lead terminals, 31 ... bonding wires, 40 ... dispensers.

Claims (8)

A moisture-sensitive film that changes its physical quantity by adsorbing moisture, a moisture-sensitive part that is covered by the moisture-sensitive film and has a pair of electrodes for detecting changes in the physical quantity, and processes the output signal of the moisture-sensitive part And a pad for outputting the output signal of the circuit element unit to the outside of the humidity sensor by being electrically connected to the bonding wire, and the humidity change of the atmosphere is A humidity sensor for detecting changes,
A humidity sensor, wherein a connection portion of the pad with the bonding wire is covered with a pad protective film formed of the same material as that of the moisture sensitive film.   The humidity sensor according to claim 1, wherein the pad protective film is formed integrally with the moisture sensitive film.   The humidity sensor according to claim 2, wherein the entire surface of the substrate is covered with the moisture-sensitive film and the pad protective film.   The humidity sensor according to claim 1, wherein the moisture-sensitive film and the pad protective film are formed through a dispenser. A moisture-sensitive film that changes its physical quantity by adsorbing moisture, a moisture-sensitive part that is covered by the moisture-sensitive film and has a pair of electrodes for detecting changes in the physical quantity, and processes the output signal of the moisture-sensitive part And a pad for outputting the output signal of the circuit element unit to the outside of the humidity sensor by being electrically connected to the bonding wire, and the humidity change of the atmosphere is A method of manufacturing a humidity sensor that detects a change, comprising:
A method of manufacturing a humidity sensor, comprising: forming a pad protective film that covers a connection portion of the pad with the bonding wire by using the same material as that for forming the moisture sensitive film.   The method of manufacturing a humidity sensor according to claim 5, wherein the pad protective film is formed integrally with the moisture sensitive film.   The method for manufacturing a humidity sensor according to claim 6, wherein an entire surface of the substrate is covered with the moisture sensitive film and the pad protective film.   The method for manufacturing a humidity sensor according to any one of claims 5 to 7, wherein the moisture-sensitive film and the pad protective film are formed through a dispenser.

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