FI113806B - Moisture detection elements and method for making them - Google Patents

Description

, 113806

Moisture Detection Element and Method of Manufacture

BACKGROUND OF THE INVENTION The present invention relates to a capacitive moisture sensing element having a moisture sensitive membrane comprising an organic polymerized resin material and a process for making it, and more particularly to the structure and method 10 of an upper electrode end piece.

This type of conventional moisture sensing element is formed by sequentially stacking a lower electrode in the form of a thin film, an organic polymeric resin material moisture sensitive film and an upper electrode in the form of a thin film on the surface of the substrate. In this element, the change in capacitance or impedance between the opposing electrodes relative to the relative humidity of the moisture-sensitive film is measured as the change in humidity.

Figures 5A-5D show a conventionally proposed method for manufacturing a moisture detection element 20. First. As shown in Fig. 5A, a lower electrode 2 is formed in the form of a thin film, a lower electrode connection end piece 2a and an upper electrode end piece 4a are formed on the surface of the insulating substrate 1. Then, as shown in Fig. 5B, 5B, a moisture-sensitive film 3 is formed over the entire region of the insulating sub-: ': strate 1, except for the end regions. As shown in Fig. 5C, the upper electrode 4 is formed on the moisture-sensitive membrane 3 together with the extended portion 4b of the upper electrode 4b, a portion extending over the upper electrode contact piece 4a. As shown in Fig. 5D, the stepped portion of the upper electrode: the contact terminal piece 4a and the expanded portion 4b is finally coated with a precious metal. with diaphragm 5 for coupling the upper electrode end piece 4a ι ·>. 35 to the electrically expanded part 4b. The wires 6 are then connected to the upper electrode terminal block 4a and the 2-13806 to the lower electrode terminal block 2a. By this construction, the change in capacitance or impedance between the upper electrode 4 and the lower electrode 2 relative to the relative humidity of the moisture sensitive film 3 is reduced as a change in humidity. Note that this type of moisture detection element is incorporated, for example, in JP-Laid-Open No. 60-239657.

However, this humidity detection element having the above arrangement has problems such as a more complicated manufacturing process and lower productivity because the portion between the expanded portion 4b of the upper electrode 4 and the upper electrode connection piece 4a is covered with a reinforcing precious metal foil 5 and an upper electrode 4 6, as shown in FIG.

In addition, the interface structures between the moisture sensitive film 3 and the reinforcing noble metal film 5 and the precious metal film 5 and the expanded part 4b of the upper electrode 4 are complex. For this reason, it is very likely that at these interfaces, disintegration occurs by thermal shock, expansion or shrinkage of the moisture sensitive membrane 3 when moisture is absorbed or desorbed, or the like, which poses problems in the form of long-term V stability.

• 25 Reinforcing precious metal film 5 is manufactured to a very J *: thickness. As a result, residual stresses tend to remain in the polymeric resin material, resulting in poor reliability in the form of chemical resistance and environmental resistance.

In addition, the soldering and brazing material for the electrical connection of the wires 6 for the upper electrode connection terminal piece 4a decomposes the materials for the upper electrode 4 and the precious metal film 5. For this reason, great. , ·, Electrical connection with mechanical strength cannot be implemented i · i 35.

• · 3 113806

In addition, a thin metal foil, a thick metal film, a bulk metal or the like is applied to the lower electrode 2 in a moisture sensing element having the above arrangements. If very small holes are present in the 5 moisture sensitive membrane 3 formed in the electrode 2, deteriorating insulating properties result in leakage currents and short circuits. With 4.

As a way of solving such problems, a structure is provided to prevent the short-circuiting mentioned above, in which the single crystal silicon is used as the substrate 1 material in the structure, while the lower electrode 2 and the thermal oxide film are used as an insulating film. However, there is a limitation to the substrate material used in such a structure, and the insulating film is also limited to SiO2 15 in order to narrow the range of materials that prevent the design of the optimum moisture sensing element. In addition, the capacitance between the lower electrode 2 and the upper electrode 4 changes depending on the voltage applied and the measuring frequency used between them. As a result, very high precision moisture detection cannot be performed.

In addition, as a second means of solving such problems, a structure in which a corrosion-resistant metal 9, · · · · · · · · · · ·, that can be covered with an oxide film, e.g. Ta, · it V · is applied to the lower electrode 2 and -

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l *: 25 is formed by a wet forming system which acts as an insulating process. In such a structure precious metal,: * · *; having stable properties, e.g. Pt, Au or Pd, cannot be used as the electrode material to the lower electrode 2, which results in a narrow choice of material. Therefore, the optimal structure of "I! 30" cannot be achieved in the form of long-term stability.

j \; SUMMARY OF THE INVENTION: The present invention relates to a humidity detecting element, characterized by what is stated in claim 1 of patent * 35. The invention also relates to a method for manufacturing a humidity detection element, characterized by the method of claim 1 4. Preferred embodiments of the invention are set forth in the dependent claims.

It is an object of the present invention to provide a moisture detection element and a method for making the same which can improve electrical coupling properties between the upper electrode and the upper electrode end piece, and between the upper electrode end piece, lower electrode end piece and wires thereby providing an improvement in quality and reliability.

Another object of the present invention is to provide a moisture detection element and a method of making the same which can detect electrical coupling portions between the upper electrode and the upper electrode end piece 15 and between the upper electrode end piece, lower electrode end piece and wires by a simple method and high productivity.

It is yet another object of the present invention to provide a moisture sensing element that can prevent degrading and short-circuiting dielectric properties between the upper electrode and the lower electrode, even when the moisture-sensitive hand membrane has very small holes, thus: · ·· long-term stability is achieved.

It is yet another object of the present invention to provide • · *: *: 25 a moisture detection element that permits selection of the most suitable materials from substrate materials, electrode materials, and polymeric resin materials. design freedom and improve reliability.

'!!! In order to achieve the above objects, according to the present invention, there is provided a moisture detection element, wherein the electrode metal layers (pads):; for the upper and lower electrodes, a substrate is formed, an expanded portion consisting of a terminal portion of the upper electrode 35 is stacked over the metal layer '1 of the electrode to form the upper electrode end piece, and the same 5 113806 electrode material for the upper electrode is stacked on the metal layer the lower electrode forming the lower electrode end piece.

According to the present invention there is provided a method of manufacturing a moisture 5 sensing element, comprising the steps of forming an electrode material film on a substrate and patterning a film to form a lower electrode, a lower electrode metal layer and a higher electrode metal layer; corresponding to the region of formation of the metal layer of the electrode on the substrate, and depositing the electrode material on the moisture-sensitive film at a temperature not lower than the glass transition temperature or the soft point of the organic polymer resin material by 50 ° C layer, while covering the stepped portion and pi-2 0 by lowering the lower electrode end piece the upper electrode end piece and the lower electrode metal layer.

BRIEF DESCRIPTION OF THE DRAWINGS: ·· FIGS. IA-1C are views illustrating an arrangement of a moisture detection element according to an embodiment of the present invention;

Figures 2A-2D are cross-sectional views illustrating a method for manufacturing a moisture detection element according to the present invention;

Figures 3A and 3B are cross-sectional views showing a moisture sensing element according to a second embodiment of the present invention; Figures 4A-4F are cross-sectional views of the figures: 3A and 3B for illustrating a method for manufacturing a moisture detection element according to the present invention; > · T 6 113806

Figures 5A-5D are plan views illustrating a conventional method of manufacturing a moisture detection element according to the present invention; and

Fig. 6 is a perspective view showing the arrangement of a conventional 5 humidity detection element.

Description of Preferred Embodiments

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Figures IA-1C illustrate a moisture detection element according to the present invention: Referring to Figures IA-1C, reference numeral 11 indicates a substrate; 12 lower electrodes formed on substrate 11 to a thickness of about 500 to 10,000 Å; 12a a metal layer of a lower portion of the lower electrode 12 laa-15 formed integral with the metal layer region of the electrode on the substrate 11 for connection to the lower electrode 12; 13 moisture-sensitive films consisting of an organic polymeric resin material formed on the lower electrode 12 to a thickness of about 1-10 μπΐ: η 20; and 13a a stepped portion 'formed by treating that portion of the moisture-sensitive film' · k 13 located in the metal layer region of the electrode, inclined; '·· but for the share.

V · Reference numeral 14 denotes an upper electrode, which is formed on a moisture sensitive film 13 at a thickness in the range of 200-2000 Å; 14a for the upper electrode metal layer of the upper electrode 14, a metal layer formed in the region of the forming metal layer of the electrode on the substrate 11 in the form of an islet in the same process as for the lower electrode 12; and 14b; An expanded area formed as part of the upper electrode 14, which partially covers the inclined stepped portion 13a and expands over the metal layer k of the upper electrode · The expanded portion 14b is stacked on the upper electrode end member of the upper electrode * · · 35 1 to 1. Reference numeral 16 indicates an electrode shielding metal layer consisting of the same electrode material as the upper electrode 14 and stacked with the lower electrode metal layer 12a at the same time as the upper electrode 14 is formed. the extended portion of electrode 12 we a barrier layer 12a for forming a lower electrode end piece 17. Reference numeral 18 indicates the wires connected / secured to the upper electrode terminal block 15 and the lower electrode terminal block 17 by solder metal 19.

In this arrangement, the upper electrode terminal block 15 has a two-layer structure comprising a metal layer 14a of the upper electrode and an expanded portion 14b of the upper electrode 14. For this reason, although the lead 18 would be coupled to the upper electrode end piece 15 by brazing metal 19 or brazing, although the brazing metal or brazing material melts the material for the thin expanded portion 14b (200-2000 Å), disconnection may be prevented -20 ros 14a, which is relatively thick (500-10,000 Å), is formed under the expanded portion 14b. The wire 18 may be *: additionally coupled to the upper electrode terminal block 15 having a double-layer structure, with solder metal 19 or brazing:, wire attachment, welding, or conductive resin bonding material to achieve: stable electrical connection with high mechanical strength. With respect to the lower electrode end piece 17, the same effects described above can be observed.

. In the arrangement described above, the thickness of the upper electrode 14 is set within the range of 200 to 2000 Å. If the thickness is ** · 'less than 200 Å, the expanded portion 14b is not the upper electrode mesh; ·; rather than the protective metal layer 16 of the extended part 1t of the electrode 12 in the metal layer 12a of the lower part 12 of the electrode 12 can be mechanically very strong. If the thickness exceeds 2000 Å, good permeability '* will not be achieved. Therefore, by setting the thickness of the upper electrode 14 within the limits of? 113806 Ο 200 - 2000 Å, mechanically strong upper and lower electrode end pieces 15 and 17 and an upper permeable electrode 14 can be realized.

Figures 2A-2D illustrate a method of manufacturing a moisture detection element in accordance with the present invention. First, as shown in Fig. 2A, a metal layer is formed by deposition or sputtering of the substrate 11 having a thickness of about 0.5 mm to 500-5000 Å 10. The substrate 11 comprises an insulating material such as alkaline glass, a thermally oxidized discrete deposit, sapphire, alumina or quartz or a semiconductor material such as silicon. The metal layer is formed by at least one layer comprising Pt, 15 Au, Nb / Pt, Cr / Pt and Ti / Pt, respectively. The metal layer is then patterned so as to simultaneously form a lower electrode 12, an expanded portion of the electrode 12a for the lower electrode 12, and a metal layer 14a for the upper electrode.

In the next step, drop as in Figure 2B

illustrates an organic polymerized resin material solution such as PMMA, crosslinked PMMA, polyimide, * '·· polysulfone or polyether sulfone for substrate 11, where: * the lower electrode, the extended portion of the lower electrode · * · *: 25 metal layer 12a and upper electrode metal layer 14a · '· *. is formed, and the spin coating is performed at about 1000 to 5000 revolutions per minute. The resulting structure is then dried and subjected to heat treatment at 100-450 ° C for 1-100 hours with single or multi-temperature 30 sheets. In this process, a polymerized resin film ·; · is formed to provide a moisture-sensitive film 13 having a thickness of j *: 1 to 10 μτη: η and having stable properties as a moisture-sensitive material.

Subsequently, as shown in Figure 2C, a mask 20 consisting of alkaline glass, * '· quartz, sapphire, or the like, and having an opening 9 113806 in the formation region of the electrode end piece, is positioned over the moisture-sensitive film 13 thus formed. Then, dry etching from a position above the substrate 11 in the direction indicated by the arrows A under the conditions 5 described below to remove a portion of the moisture-sensitive film 13 corresponding to the metal layer formation area of the electrode and expose the metal layer 12a (not shown) metal liqueur 14a. By such a process, the stepped portion 13a of the moisture-sensitive film 10 13 is formed such that it has an inclined surface. The conditions for dry etching are set as follows. Gases such as O 2, Ar or CF 4 are used alone or in a mixture of more than one. The pressure is set from 0.1 to several torr. The high frequency output 15 is set to 100 - 500 W.

Finally, as shown in Figure 2D, after removal of the mask 20 from the moisture-sensitive film 13, a metal film with high corrosion resistance and high permeability, such as Au, Pt or Pd, is formed on the substrate 20 by deposition, sputtering, or ion plating 200. - 2000 Å while '. ·· The heat treatment is performed under the following conditions. The metal membrane is then patterned to form the upper electrode 14: a portion of the inclined stepped portion 13a of the moisture sensitive film 13, the metal layer 14a of the upper electrode t and the metal layer 12a of the extended portion of the lower electrode 12. By this process, as shown in Figure 2D, an expanded portion 14b of the upper electrode 14 is formed in the metal layer 14a of the upper electrode, thereby forming an upper electrode end piece 15 having a * ··· * bilayer structure. In addition, as shown in Fig. 1a '**, a protective metal layer 16 of the lower electrode is formed; an extended portion of the electrode 12 over the metal layer 12a to form a lower electrode end piece 17 having a double: 3 successive structure.

• · * * * 10 113806

Consider the temperature at which the metal is heated to form the upper electrode 14. It is assumed that an organic polymerized resin material having a glass transition temperature Tg or a softening point Ts of 200 is used for a moisture-sensitive film 13. In this case, by forming the thin film while heating the material at a temperature of from 150 to 350 ° C, an upper electrode 14 with excellent permeability up to 200-2000 Å can be formed. In this case, the glass transition temperature Tg or the softening point Ts is within a considerable range and almost the same heating effect as that described above can be observed at a temperature slightly lower than the slightly measured glass transition temperature Tg or softening point Ts. For this reason, thin-film forming can even be accomplished by heating the material at 150 ° C, which is 50 ° C lower than the glass transition temperature Tg or soft point Ts. For example, if an upper electrode 14 having a thickness of 900 Å is formed by setting the heating temperature to about 300 ° C, the hysteresis (difference between the moisture sensitive properties of the moisture-sensitive foil 13 and the corresponding moisture desorption-i process) is about 0.5%. RH. In other words, one can: '· obtain a moisture sensing element with excellent sensitivity:::.

Since the upper electrode 14 is formed at temperature • V. which is equal to or greater by a factor of 50 ° C (Tg or. Ts-50 ° C) than a temperature lower than the conversion temperature of the glass of the organic polymerized resin material. the state Tg or soft point Ts on the moisture-sensitive film 13, 30 according to this method have good adhesion and good permeability properties of the upper electrode 14 to the organic polymerized resin material, thereby widening the range of process conditions and improving process stability.

The method further comprises a two-layer structure of an upper electrode end piece 15 wherein an expanded portion 14b of an upper electrode 11 113806 14 is formed over a metal layer 14a of an upper electrode and a double layer structure of a lower electrode end piece 17 wherein a protective electrode layer 16 is formed portion on top of the metal layer 12a, is formed by the same process as the process by which the upper electrode 14 is formed. Therefore, the manufacturing process has been simplified to improve productivity.

Further, according to the method, positioning when the moisture-sensitive film 13 is subjected to dry etching relative to the substrate 11 reference points can be easily performed using a mask 20. A plurality of discs can therefore be simultaneously processed in batch processing at high position accuracy, thereby improving productivity.

Further, according to the method, since the patterning for the moisture sensitive film 13 is carried out as a dry etching, the film is completely free from contact with the resist solution, leach solution and the like, and dust from subsequent processes. Therefore, a moisture-sensitive film having a surface of 20% clean can be obtained.

Further according to the method, since the stepped portion of the moisture sensitive film 13 is formed such that • '·. it has a slightly sloping surface, forming the upper; ; : the extended portion 14b of the electrode 14 along the inclined surface of the 25 stepped portion 13a of the moisture sensitive film 13 in a tight • ·. **. in contact with that which provides good stair coverage. If etching is performed using a photoresist, the stepped portion is formed to have a steep, sloping surface. For this reason, the metal film tends to be polished ;;; With 30 lymphatic staggered sections, thin and disconnected

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'; · * Which tends to take place with a polymeric stepped portion; ·: Della. In contrast to this mask etching, the etching gas flows under the mask, so that the polymeric stepped portion is formed so that it has a gradually tilted »» · 35 surface, thus preventing open impurities and the like.

• · 12 113806

Further, since the upper electrode 14 has good adhesion properties to the moisture-sensitive film 13, the adhesive strength of the upper electrode 14 relative to the stepped portion 13a 5 of the moisture-sensitive film 13 is increased to prevent the occurrence of discharge.

As described above, the electrical coupling properties of the moisture sensing element of the present invention between the upper electrode and the upper electrode -10 terminal and the lower electrode and lower electrode terminal member can be improved. Therefore, stable electrical switching properties can be maintained for long periods of time and improvements in quality and reliability can be achieved.

Further, according to the method of manufacturing the moisture detection element of the present invention, the electrical coupling portion between the upper electrode and the upper electrode end piece, the upper electrode end piece and the lower electrode end piece may be formed simultaneously in the process of forming the 20 upper electrode. Therefore, productivity can be improved by a simple process.

Figures 3A and 3B and 4A-4F illustrate yet another embodiment of the present invention in which a thin insulating film is formed on a lower electrode. The same reference numerals 25 as in Figures 3A and 3B and 4A to 4F indicate the same parts as in Figures IA-1C and 2A-2D. 30 denotes a thin insulating film consisting of a nitride or oxide, such as AlOx, SiOx, SiNx, SiOxNy, TaOx or NbOx, and is formed on the lower electrode 12 from about 100 to about 10,000; ;; 30 Ä thick.

Since the insulating film 30 having a thickness of about 100 to 10,000 Å is produced on the surface of the lower electrode 12, the surface of the lower electrode 12, which is brought into contact with the moisture-sensitive film 13, is completely t ; * [35 covered to be insulating. Therefore, it is possible to achieve

'* I

13 113806, even if there are very small holes in the moisture sensitive film. In other words, there is no deterioration or short-circuiting of the insulating properties of the moisture-sensitive membrane 13 between the lower electrode 12 and the upper electrode 14 in the moisture-sensitive membrane 13, thereby reliably preventing initial failure, short-circuiting and the like. Thus, no insulation failure and short-circuiting will occur over a long period of time, resulting in improvements in stability and reliability.

Since the insulating film 30 is made of an insulating material formed by nitrides or an oxide such as A10x, SiOx, SiNx, SiOxNx, TaOx or NbOx, the surface of the lower electrode 12 can be insulated independently of the combination of noble gas containing electrodes and for the polymerized resin material upper electrode 14. Therefore, the degree of freedom of the structure can be greatly increased.

Further, in this arrangement, the insulating film 30 is formed to a thickness of 100 to 10,000 Å. At thicknesses of less than 100 Å, very small holes and the like tend to form, and the lower electrode 12 cannot be manufactured with a film having insulating properties! '. would be good. If the thickness exceeds 10,000 Å, a dielectric is produced; ; ; The film is stressed and a film with high adhesion strength and no cracking is obtained. Therefore, the thickness of the insulating film 30 is set between 100 and 10,000 Å to obtain good compatibility between the electrode material and the polymerized resin material and to ensure reliable insulation properties.

'*' · 30 Figures 4A-4F illustrate a method of manufacturing the moisture detection element shown in Figures 3A and 3B. Ku -. * · '; 4A, the metal is first formed by forming an electrode * of a substrate 11 about 0.5 mm thick. by coating or sputtering to a thickness

1 »I

35,500 - 5,000 Ä. The substrate 11 consists of an insulating material such as alkaline glass, quartz, sapphire 14 113806 or alumina or a semiconductor material such as a discrete crystal having an oxide film. The metal is formed by at least one layer composed of noble gases such as Pt, Au and Pd. The metal film is then patterned 5 to simultaneously form the lower electrode 12, the metal layer 12a (not shown) of the expanded portion of the lower electrode 12, and the upper electrode end piece 14a.

Afterwards, as shown in Fig. 4B, an insulating material consisting of a nitride or oxide such as 10 Al, SiOx, SiNx, SiOxNy TaOx or NbOx is formed on the surface of the lower electrode 12 by deposition or sputtering by ionic plating or CDV 100-10,000. Ä and is patterned using a mask or LO system or photolithographic method to form a thin insulating film 30.

Then, as shown in Fig. 4C, a solution in which an oligomer, such as a polymerized resin material, is dissolved, is dropped onto a substrate 11 on which a lower electrode 12 having an insulating film 30, a lower electrode expanded portion metal layer 12a and an upper electrode end piece 14a is formed. The coating of the solution is accomplished by spin coating at a rotation speed of about 1000 to 5000 revolutions per minute, dip coating, or plasma polymerization. Sen; v. After 25, the resulting structure is dried and exposed to heat.

• I

• 100 to 450 ° C for 1 to 100 hours with single or multi temperature profiles. This process polymerizes

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'Oligomer to a thickness of about 1 to 10 μτη: η to form a moisture sensitive film 13 and to exhibit stable properties as a moisture sensitive material.

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As shown in Figure 4D, the moisture-sensitive film 13 thus formed is patterned by wet etching based on a photolithographic method, by dry etching or by the LO method to remove a portion of the "J." 35 sensitive film which corresponds to the area of formation of the metal layer of the electrode on the substrate 11 and exposing the metal layer 12a (not shown) of the lower electrode 12 and the metal layer 14a of the upper electrode.

It is assumed that the patterning will be accomplished by the dry weaving method. In this case, as the 4D shown in Figure 5, the mask 20 consisting of e.g. alkali glass, quartz or sapphire and has an opening elec-rodipäatekappaleen the catchment area, placed in smooth water-usherkälle film 13, and dry etching is carried out from the substrate 11 above the point of the arrow A indicated by 10 in the direction described above to remove the portion of the moisture-sensitive film 13 which corresponds to the metal layer of the electrode and exposes the expanded layer of electrode 12 to the metal layer 12a (not shown) and the upper electrode metal layer 14a. By this process, the stepped portion of the moisture-sensitive cal-15 von 13 is formed to have a gently sloping surface. The conditions for dry etching are set as follows. Gases such as O2, Ar and CF4 are used alone or in combination of more than one. The pressure is set from 0.1 to several torr. The high frequency output 20 is 100 to 500 W.

Subsequently, as shown in Figure 4E, when the mask 20 is removed from the moisture-sensitive film 13, a metal film with high corrosion resistance and high permeability, such as Au, Pt and Pd, is formed on the substrate 11 by ϊ 25 by deposition, sputtering, ion plating 100. -: ·: up to 2000 Ä thickness while undergoing heat treatment under the following conditions. The metal film is patterned to form the upper electrode 14 on the end surfaces of the moisture sensitive film 13, the inclined stepped portion 30 of the moisture sensitive film 13, and the top electrode 14a of the metal layer 14a. By this process, the upper electrode 14 expanded! The V portion 14b is stacked on the main surface of the metal layer 14a of the upper electrode to form the upper electrode end piece 15,. with a two-layer structure.

; 35. As shown in Figure 4F, in this way been formed the upper electrode 14 is patterned after the excitation of the feet 16 113806 by the laser beam from above the upper electrode 14 in the direction indicated by the arrow A. As a result, the upper electrode 14 may have an electrode area that provides a predetermined capacitance. By tuning the moisture-sensitive membrane 5 13 at the same time as the upper electrode 14 is tuned, arbitrary capacitance can be set. The same effects as described above can be obtained when the upper electrode 14 is excited by a mechanical metal removal method such as scratching instead of laser irradiation based on Virit-10.

According to this method, a large number of interchangeable elements with nearly predetermined capacitance and which do not pose problems in the form of quality or reliability can be produced by performing a tuning process based on laser radiation or mechanical metal removal.

Further, according to the method, the two-layer structure of the upper electrode terminal body 15, in which the expanded portion 14b of the upper electrode 14 is formed over the metal layer 14a of the upper electrode 20, can be formed by the same process as the upper electrode 14. Therefore, the manufacturing process is simplified and productivity can be improved.

When the moisture sensitive film 13 is subjected to dry etching according to the method, positioning at substrate 11 reference sites can be easily performed using mask 20. Therefore, a plurality of discs can be processed simultaneously with a high local precision, thus improving productivity.

Further, according to the method, since the patterning of the moisture-sensitive film 13 is performed by dry etching, the moisture-sensitive film 13 is completely free from contact with the resist solution, the leach solution and the like, and dust from the following processes. Therefore, a moisture sensitive membrane 13 having a clean surface can be obtained.

• · 17 113806

Further, since the stepped portion 13a of the moisture sensitive film 13 is formed to have a sloping inclined surface, the extended portion 14b of the upper electrode 14 is formed along the inclined surface of the stepped portion 13a of the moisture sensitive membrane 13 in close contact therewith and a slightly sloping surface is formed. Since the steep polymeric stepped portion is not formed, a good stair cover can be obtained, thus preventing short circuits and the like.

Further, according to the method, since the upper electrode 14 has good adhesive properties to the moisture sensitive film 13, the adhesive strength of the upper electrode 14 relative to the stepped portion 13 of the moisture sensitive film 13 is increased to prevent mechanical removal.

As described above, according to an embodiment of the method shown in Figures 3A-4F, since a thin insulating film is formed on the lower electrode to insulate the lower electrode surface, although the moisture-sensitive film has very small holes between the upper and lower electrodes, . Therefore, insulation failure and short circuiting * - · does not occur over a long period of time, which ensures consistent quality · and high reliability over a long period of time. In addition, the insulating Γ *: 25 film is not affected by the combination of the substrate material, the electrode material, and the polymerized resin material, and a combination of materials with good compatibility can be selected. Therefore, the degree of freedom of the structure can be increased and very reliable moisture can be obtained '!!! 30 detection elements.

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Claims (8)

1. Moisture detection element consisting of a substrate (11), an upper electrode (11) formed on the substrate (11), a moisture sensitive membrane (13) formed on the lower electrode (12) by organic polymeric resin. material and a permeable upper electrode (14) formed on the moisture-sensitive membrane (13), characterized in that the moisture detection element comprises an upper electrode (14) substrate (11) formed for the upper electrode metal layer (14a). which layer is adjacent one end of the moisture-sensitive membrane (13), an extended portion (14b) of the upper electrode, which portion extends from the upper electrode (14) to the metal layer (14a) of the upper electrode, the expanded portion ( 14b) expands along a sloping surface (13a) formed at the other end of the moisture-sensitive membrane (13) and in contact with the same, the extended portion further extending over the metal layer 20 (14a) of the upper electrode. and star in contact with the same. Moisture detection element according to claim 1, characterized in that it further contains: \. an upper substrate (11) formed and associated with the same lower electrode (12) and an electrode material layer 25 (16) consisting of the same material as the upper electrode (14) and piled on top of the metal layer (12a) for the lower the extended portion of the electrode (12) to form a lower electrode end piece (17). 3. An element according to claim 1, characterized in that wires (18) are connected to an upper (15) and a lower (17) electrode end piece by conductive parts (19). •> 4. An element according to claim 1 or 2, characterized in that the thickness of the upper electrode is installed within the range 200 - 2000 Å. A method of producing a moisture detection element, characterized in that it comprises the steps of: an electrode material film is formed on top of a substrate (11) and the film is patterned to form a lower electrode (12), a metal layer (12a) for an expanded portion of the lower electrode (12) and a metal layer (14a) for an upper electrode; a moisture-sensitive membrane (13) is formed on top of the substrate; a stepped portion (13a) is formed by patterning the portion of the moisture-sensitive membrane which corresponds to the formation area of the metal layer of the electrode on the substrate; The electrode material is deposited on the moisture-sensitive membrane at a temperature not less than 50 ° C lower than the temperature lower than the glass transition temperature or softening point of an organic polymeric resin material, to form a permeable upper electrode (14) through stacking the one end portion of the upper electrode on top of the metal layer (14a) of the upper electrode, the stripping portion of the top portion being covered to form an upper electrode end piece (15), and electrode material being stacked on top, the metal layer (12a) for the extended portion of the lower electrode (12) to form a lower electrode end piece (17). 6. A method according to claim 5, characterized in that the electrode material of the electrode end piece (17) is stacked on top of the metal layer (12a) for the lower part of the lower electrode while forming the upper electrode. Moisture detection element according to claim 1, characterized in that an insulating film is ► ·; * ’; formed on top of the lower electrode (12) and on top of the portion of the substrate (11) adjacent to the lower electrode (12). * t 22 113806 8. An element according to claim 6, characterized in that the thickness of the insulating film is between 100 and 10,000 Å.