JP2008270447A - Thin composite element and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a small and thin composite element having high speed thermal response by forming each of a thermistor, a resistor and a capacitor with a thin film and forming them in one chip. <P>SOLUTION: In the thin composite element 10, a thin film thermistor 12, a thin film resistor 16, and a thin film capacitor 21 are spaced apart from each other and formed on an insulating substrate 11. A pair of opposed comb-type electrodes 13 and 14 are formed on the thin film thermistor, and the thin film capacitor has a lower electrode 17, a dielectric layer 18 and an upper electrode 19. One comb-type electrode 14, one end of the thin film resistor 16 and one end of the upper electrode 19 are mutually electrically connected by a connecting layer 22 on the substrate. A first led out electrode 23 electrically connected to the other comb-type electrode 13, and a second led out electrode 24 electrically connected to the other end of the thin resistor are formed on the substrate, respectively. All elements on the substrate except pads 17c, 23c, 24c for connecting the leads at the lower electrode, the first and the second led out electrodes are covered with a protective film 26. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thin composite element having a thin film thermistor, a thin film resistor, and a thin film capacitor, and a method for manufacturing the same.

  Conventionally, an oscillation type temperature measuring circuit has been disclosed as a circuit including a thermistor, a resistor, and a capacitor (for example, see Patent Document 1). In this oscillation type temperature measuring circuit, a resistor and a capacitor are connected in series to a DC power source, and a relaxation oscillation circuit that charges and discharges this capacitor in a cycle corresponding to the time constant of these resistors and the capacitor is formed, and the temperature is measured as the resistor. Switching means for alternately switching and connecting the thermistor and the reference resistor is provided, and the temperature of the thermistor is obtained by comparing the oscillation frequency when the thermistor is connected with the oscillation frequency when the reference resistor is connected. In this oscillation type temperature measuring circuit, a surge absorbing Zener diode is connected in the opposite direction between the both-end connection point of the thermistor and the both-end line of the DC power supply. According to the oscillating temperature measuring circuit of the present invention, even if a positive or negative surge voltage is induced at any of the lead wires at both ends of the thermistor, the surge voltage is absorbed to the DC power source side through the Zener diode and directly into the internal circuit. Since it is not transmitted, the conventional malfunction and element destruction do not occur, and the reliability of the circuit is greatly improved. However, in such an oscillation type temperature measuring circuit, a circuit is configured by using a plurality of individual electronic components such as a thermistor, a resistor, and a capacitor. When these components are mounted on the same substrate, the mounting area is inevitably required. As a result, the size of the circuit has been greatly reduced.

As an element having a structural feature improved in this respect, there is a composite element in which a thermistor and a resistor are connected in series, and a characteristic equivalent to a circuit in which a capacitor is connected in parallel to these thermistor and the resistor is realized on a single chip. (For example, refer to Patent Document 2). By using this composite element, it is possible to reduce the size of electronic circuits such as a temperature compensation circuit composed of a thermistor, a resistor and a capacitor. In particular, it is possible to realize a composite element useful as a temperature compensation circuit such as a temperature compensation crystal oscillator having a strong need for miniaturization.
JP 61-68526 (Claims, functions, effects of the invention) JP-A-11-307318 ([0004], [0006])

  The composite element disclosed in Patent Document 2 has a feature that a thermistor, a resistor, and a capacitor can be configured on a single chip, so that the circuit can be miniaturized. However, in this composite element, a resistor is provided on one surface of the thermistor body. The bulk structure in which the body layer is provided and the dielectric layer is provided on the other surface combines the three parts of the resistor, the capacitor, and the thermistor, so the thermistor has a large heat capacity and low thermal response. there were.

  It is an object of the present invention to provide a thin composite element having a thin and small high-speed thermal response and a method for manufacturing the same by forming a thermistor, a resistor and a capacitor from thin films into one chip.

  In the invention according to claim 1 of the present application, as shown in FIGS. 1 and 2, a thin film thermistor 12, a thin film resistor 16, and a thin film capacitor 21 are formed on an insulating substrate 11 so as to be separated from each other. A pair of facing comb electrodes 13 and 14 is formed, and a thin film capacitor 21 is formed on the lower electrode 17 formed on the substrate 11, the dielectric layer 18 formed on the lower electrode, and the dielectric layer. The connection layer 22 is formed on the substrate 11 so as to electrically connect one of the pair of comb electrodes 14, one end of the thin film resistor 16, and one end of the upper electrode 19 or the lower electrode on the substrate 11. A first extraction electrode 23 is formed on the substrate 11 so as to be electrically connected to the other 13 of the pair of comb electrodes, and is electrically connected to the other end of the thin film resistor 16 on the substrate 11. Second extraction electrode 2 Are formed, and all elements 12, 13, 13 on the substrate excluding the pad portions 17 c, 23 c, 24 c for connecting the lead lines in the lower electrode 17 or the upper electrode, the first lead electrode 23 and the second lead electrode 24, The thin composite element 10 is characterized in that a protective film 26 is formed so as to cover 14, 16, 18, 19, and 22.

7 and 8, the thin film thermistor 32, the thin film resistor 36, and the thin film capacitor lower electrode 41 are formed on the insulating substrate 31 so as to be separated from each other. A pair of comb-shaped electrodes 33 and 34 facing each other is formed on the substrate 31, and one of the pair of comb-shaped electrodes 34, one end of the thin film resistor 36, and one end of the lower electrode 41 are electrically connected to each other on the substrate 31. A connection layer 37 is formed on the substrate 31, a third extraction electrode 38 is formed on the substrate 31 so as to be electrically connected to the other of the pair of comb electrodes 33, and the other end of the thin film resistor 36 is electrically connected to the substrate 31. The fourth lead electrode 39 is formed so as to be connected to each other, and all the elements 32, 33, on the substrate except the pad portions 38c, 39c for connecting the lead lines in the third and fourth lead electrodes 38, 39 are formed. 34, 36, 37, 4 A protective film 42 made of SiO ₂ is formed so as to cover 1, and an upper electrode 43 for a thin film capacitor is formed on the lower electrode 41 via the protective film 42, and the lower electrode 41, the protective film 42, and the upper electrode 43 are formed. This is a thin composite element 30 characterized in that a thin film capacitor 44 (FIG. 8) is formed.

  As shown in FIGS. 1, 2 and 4, the invention according to claim 9 of the present application forms a thin film capacitor lower electrode 17 in a predetermined pattern on an insulating substrate 11, and a step of forming a thin film capacitor lower electrode 17 on the lower electrode 17. A step of forming the dielectric layer 18, a step of forming the thin film thermistor 12 in a predetermined pattern separately from the lower electrode 17 on the substrate 11, and a predetermined pattern separately from the lower electrode 17 and the thin film thermistor 12 on the substrate 11. Forming a thin film resistor 16, forming a pair of comb-shaped electrodes 13 and 14 on the thin film thermistor 12, forming a thin film capacitor upper electrode 19 on the dielectric layer 18, and on the substrate 11. Forming a connection layer 22 so as to electrically connect one of the pair of comb-shaped electrodes 14, one end of the thin film resistor 16, and one end of the upper electrode 19 or the lower electrode; A step of forming a first extraction electrode 23 so as to be electrically connected to the other 13 of the pair of comb electrodes, and a second extraction electrode 24 so as to be electrically connected to the other end of the thin film resistor 16 on the substrate 11. All the elements 12 on the substrate excluding the pad portions 17c, 23c, 24c for connecting the lead lines in the lower electrode 17 or the upper electrode, the first lead electrode 23, and the second lead electrode 24, 13, 14, 16, 18, 19, 22 and forming a protective film 26 so as to cover the thin composite element 10.

As shown in FIGS. 7, 8, and 9, the invention according to claim 13 includes a step of forming a thin film thermistor 32 with a predetermined pattern on an insulating substrate 31, and a thin film thermistor with a predetermined pattern on the substrate 31. The step of forming a thin film resistor 36 separately from 32, the step of forming a pair of comb electrodes 33, 34 opposite to each other on the thin film thermistor 32, and one of the pair of comb electrodes 34 on the substrate 31 and the thin film resistor Forming a connection layer 37 so as to electrically connect one end of 36 to each other, and forming a third lead electrode 38 on the substrate 31 so as to be electrically connected to the other 33 of the pair of comb electrodes. A step of forming a fourth lead electrode 39 so as to be electrically connected to the other end of the thin film resistor 36 on the substrate 31, and a thin film capacitor so as to be electrically connected to the connection layer 37 on the substrate 31. Form lower electrode 41 All the elements 32, 33, 34, 36, 37, 41 on the substrate except for the pad portions 38 c, 39 c for connecting the lead lines in the process and the third and fourth lead electrodes 38, 39 are covered. The method of manufacturing the thin composite element 30 includes a step of forming a protective film 42 made of SiO ₂ and a step of forming an upper electrode 43 for a thin film capacitor on the lower electrode 41 via the protective film 42.

  The invention according to claim 3 or 7 of the present application is the invention according to claim 1 or 5, wherein the insulating substrates 11 and 31 are silicon substrates 11 a and 31 a having insulating films 11 b and 31 b on the upper surface of the substrate, and a thin film thermistor The thin composite elements 10 and 30 are formed in which the cavities or recesses 11c and 31c of the silicon substrates 11a and 31a are formed, leaving the insulating films 11b and 31b below the layers 12 and 32.

  The invention according to claim 11 or 15 of the present application is the invention according to claim 9 or 13, wherein the insulating substrates 11 and 31 are silicon substrates 11a and 31a having insulating films 11b and 31b on the upper surface of the substrate, respectively, and a thin film thermistor This is a method for manufacturing the thin composite elements 10 and 30 in which the cavities or recesses 11c and 31c of the silicon substrates 11a and 31a are formed by etching using the insulating films 11b and 31b as etching stoppers below the layers 12 and 32.

  In the thin composite element according to claim 1 or 5 of the present application, the thermistor, the resistor and the capacitor are each a thin film and are provided on the same substrate. The composite element has a small heat capacity and high rapid thermal response. Further, as shown in FIG. 3, this thin composite element forms an oscillation type temperature measuring circuit including a thermistor 12, a resistor 16, a capacitor 21, and electrodes 17, 23, and 24. Further, since all the elements on the substrate except for the pad portion for connecting the leader line are covered with the protective film, the thermistor does not directly touch the external atmosphere. Thereby, it is hard to be influenced by the humidity of the atmosphere in which the composite element is used, and is excellent in moisture resistance.

  According to the method for manufacturing a thin composite element according to claim 9 or 13 of the present application, it is possible to manufacture a thin composite element having the above features.

  Further, in the thin composite element according to claim 3 or 7 of the present invention, since the cavity or recess of the silicon substrate is formed leaving the insulating film below the thin film thermistor, the thin film thermistor has a membrane structure, and the high-speed thermal response is further improved. Become.

  Furthermore, in the method for manufacturing a thin composite element according to claim 11 or 15 of the present application, a cavity or a recess can be easily formed in the silicon substrate by etching using the insulating film on the silicon substrate as an etching stopper.

  The best mode for carrying out the present invention will be described below.

<First Embodiment>
As shown in FIGS. 1 and 2, the thin composite element 10 according to the first embodiment of the present invention includes a thin film thermistor 12, a pair of comb electrodes 13 and 14, a thin film resistor 16, and a thin film capacitor 21 on an insulating substrate 11. A connection layer 22, a first extraction electrode 23, a second extraction electrode 24, and a protective film 26 are provided. The thin film thermistor 12, the thin film resistor 16, and the thin film capacitor 21 are formed on the substrate so as to be separated from each other. Examples of the insulating substrate 11 include those having a silicon substrate 11a and an insulating film 11b formed on the upper surface of the substrate. The silicon substrate 11 with an insulating film is preferable because a cavity or a recess (see FIGS. 5 and 6) described later can be easily formed by etching under the insulating film. Examples of other insulating substrates include glass substrates and ceramic substrates. The substrate is determined from a thickness range of 0.1 to 0.5 mm. The silicon substrate with an insulating film is formed so as to have a SiO ₂ film having a thickness of 100 to 1000 nm on the substrate surface by thermally oxidizing the silicon substrate and by chemical vapor deposition on the silicon substrate surface.

The thin film thermistor 12 is made of Mn—Co based composite metal oxide (Mn _x Co _1-x ) ₃ O ₄ (where 0.3 ≦ x ≦ 0.6), or Mn—Co based composite metal oxide with Ni, Fe , Cu and Al, a composite metal oxide containing at least one selected from the group consisting of Cu and Al (for example, (Mn _x Co _y Fe _1-xy ) ₃ O ₄ (provided that 0.2 ≦ x ≦ 0.6, 0. 02 ≦ y ≦ 0.65) This composite metal oxide has a spinel crystal structure and a columnar crystal structure extending in the film thickness direction.Mn, Co The composition ratio of Ni, Fe, Cu, Al, etc. is determined according to the desired characteristics of the thermistor, and the thickness of the thin film thermistor 12 is determined from the range of 100 to 1000 nm according to the desired characteristics. In this embodiment, the thin film resistance is a desired value. It is formed in a shape like folded resistance wire in order to obtain the anti-values.

The thin film capacitor 21 is formed on the dielectric layer with a lower electrode 17 formed on the insulating substrate 11, a dielectric layer 18 formed on the lower electrode with a smaller area than the lower electrode, and with a smaller area than the dielectric layer. And the upper electrode 19. That is, a part of the lower electrode 17 is exposed even after the dielectric layer and the upper electrode are laminated in order to form the pad portion 17c for connecting the lead line in the lower electrode. The dielectric layer 18 is a complex oxide made of (Ba _1-x Sr _x ) TiO ₃ (where 0 ≦ x ≦ 1.0) and has a perovskite structure. The thickness of the dielectric layer is determined from the range of 100 to 1000 nm according to desired characteristics.

  The pair of comb-shaped electrodes 13 and 14 are formed by bonding layers 13a and 14a such as Cr and Ti formed on the thin film thermistor 12, Au formed on the bonding layer in the same shape and size as the bonding layers, It is composed of conductive layers 13b and 14b such as Pt. Also, the lower electrode 17 and the upper electrode 19 for the thin film capacitor are formed by bonding layers 17a and 19a such as Cr and Ti formed on the insulating substrate and the dielectric layer, respectively, and the same shape and size as the bonding layer on the bonding layer. And the conductive layers 17b and 19b made of Au, Pt or the like. The connection layer 22 includes a bonding layer 22a made of Cr, Ti or the like formed on an insulating substrate, and a conductive layer 22b made of Au, Pt or the like formed on the bonding layer in the same shape and size as the bonding layer. Consists of. The connection layer 22 is formed on the substrate so as to electrically connect one of the comb electrodes 14, one end of the thin film resistor 16, and one end of the upper electrode 19.

The first extraction electrode 23 includes a bonding layer 23a made of Cr, Ti or the like formed on an insulating substrate, and a conductive layer made of Au, Pt or the like formed on the bonding layer in the same shape and size as the bonding layer. 23b, and the second extraction electrode 24 is similarly configured. The first extraction electrode 23 is electrically connected to the other comb electrode 13, and the second extraction electrode 24 is electrically connected to the other end of the thin film resistor 16. The bonding layer has a function of increasing the degree of bonding of the conductive layer to an insulating substrate or the like as a base layer of the conductive layer. Further, all elements on the substrate except for the pad portions 17c, 23c, 24 for connecting lead wires (not shown) such as lead wires in the lower electrode 17, the first and second lead electrodes 23, 24, that is, The thin film thermistor 12, the pair of comb electrodes 13, 14, the thin film resistor 16, the dielectric layer 18, the upper electrode 19, and the connection layer 22 are protective films such as silicon dioxide (SiO ₂ ) and silicon nitride (Si ₃ N ₄ ). 26. As a result, as shown in FIG. 3, an oscillation type temperature measuring circuit having the thermistor 12, the resistor 16, the capacitor 21, and the electrodes 17, 23, 24 is formed. A thin composite element 10 of 4 mm and a width of 1 to 4 mm is obtained.

  In the above embodiment, a part of the lower electrode 17 of the thin film capacitor is exposed to form the pad portion 17c for connecting a lead line such as a lead wire. However, the lower electrode, the dielectric layer, The pads may be provided on the upper electrode by increasing the area in the order of the upper electrode. In this case, one end of the lower electrode is connected to the connection layer.

<Second Embodiment>
As shown in FIGS. 7 and 8, the thin composite element 30 according to the second embodiment of the present invention includes a thin film thermistor 32, a pair of comb-shaped electrodes 33 and 34, a thin film resistor 36, and a connection layer 37 on an insulating substrate 31. A thin film capacitor 44 including a third extraction electrode 38, a fourth extraction electrode 39, a protective film 42, a lower electrode 41, a protective film 42, and an upper electrode 43 is provided. Examples of the insulating substrate 31 include those having a silicon substrate 31a and an insulating film 31b formed on the upper surface of the substrate. The silicon substrate 31 with an insulating film is preferable because a cavity or a concave portion (see FIGS. 10 and 11) described later can be easily formed by etching under the insulating film. The thickness and type of the insulating substrate and the method for manufacturing the silicon substrate with the insulating film are the same as those in the first embodiment.

  The composition of the thin film thermistor 32 formed on the insulating substrate 31 is the same as that of the thin film thermistor 12 of the first embodiment, and the shape, size and arrangement of the thin film thermistor 32 are the same as those of the thin film thermistor 32 of the first embodiment. The thermistor 12 has almost the same shape, size and arrangement. Similarly, the composition, shape, size and arrangement of the pair of comb electrodes 33 and 34 are the same as the composition, shape, size and arrangement of the pair of comb electrodes 13 and 14. The composition of the thin film resistor 36 is the same as that of the thin film resistor 16 of the first embodiment, and the shape, size, and arrangement of the thin film resistor 36 are the same as those of the thin film resistor 16 of the first embodiment. Almost the same as the arrangement. The composition, shape, size, and arrangement of the third and fourth extraction electrodes 38, 39 are substantially the same as the shape, size, and arrangement of the first and second extraction electrodes 23, 24 of the first embodiment.

The characteristic configuration of this embodiment is the configuration of a thin film capacitor. As shown in FIG. 8, in this thin film capacitor 44, a lower electrode 41 is formed on an insulating substrate 31, this lower electrode is covered with a protective film 42 to be described later, and the upper electrode is placed on the lower electrode via the protective film 42. It is comprised by forming 43. The connection layer 37 is formed on the substrate so as to electrically connect one comb electrode 34, one end of the thin film resistor 36, and one end of the lower electrode 41 to each other. The protective film 42 in this embodiment is made of silicon dioxide (SiO ₂ ) having dielectric properties. Similar to the protective film 26 of the first embodiment, the pad portion 38c of the third lead electrode 38c and the pad portion 39c of the fourth lead electrode 39 for connecting a lead wire (not shown) such as a lead wire are excluded. The protective film 42 covers all the elements, that is, the thin film thermistor 32, the pair of comb electrodes 33 and 34, the thin film resistor 36, the connection layer 37, and the lower electrode 41. By configuring the thin film capacitor 44 as described above, the thin film capacitor 44 can be reduced in size and cost. As a result, a thin composite element 30 having a total thickness of 0.1 to 0.5 mm and a length of 1 to 4 mm and a width of 1 to 4 mm is obtained.

<Third Embodiment>
As shown in FIG. 5, the thin composite element 10 according to the third embodiment of the present invention includes a recess 11c in the silicon substrate 11a, leaving an insulating film 11b below the thin film thermistor 12 of the thin composite element 10 according to the first embodiment. Is formed. Although not shown, a cavity may be used instead of the recess 11c.

<Fourth embodiment>
As shown in FIG. 10, the thin composite element 30 of the fourth embodiment of the present invention has a recess 31c in the silicon substrate 31a, leaving an insulating film 31b below the thin film thermistor 32 of the thin composite element 30 of the second embodiment. Is formed. Although not shown, a cavity may be used instead of the recess 31c.

  Next, examples of the present invention will be described.

<Example 1>
A method for manufacturing the thin composite element shown in FIGS. 1 and 2 will be described. First, as shown in FIG. 4A, a SiO ₂ layer 11b having a layer thickness of 500 nm is formed on a silicon substrate 11a having a thickness of 0.25 mm by a thermal oxidation method.
(a) Formation of Thin Film Capacitor Excluding Upper Electrode In order to form the lower electrode 17 for the thin film capacitor, a Cr thin film is formed on the entire upper surface of the SiO ₂ layer 11b by a sputtering method so as to have a film thickness of 100 nm. Subsequently, an Au thin film is formed on the Cr thin film by sputtering so that the film thickness becomes 200 nm. A photosensitive resin is formed on the entire surface of the Au thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the Au thin film is patterned by wet etching using a potassium iodide iodide solution to obtain a desired conductive layer 17b of the lower electrode 17 (FIG. 2). Subsequently, the Cr thin film is patterned into the same structure as the Au thin film by wet etching using a cerium ammonium nitrate solution, and a bonding layer 17a is formed on the SiO ₂ layer 11b as shown in FIG. 4B. (FIG. 2), the thin film capacitor lower electrode 17 is obtained.

A photosensitive resin is formed on the entire upper surface of the SiO ₂ layer 11b and the lower electrode 17, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, a thin film of composite oxide made of Ba _0.7 Sr _0.3 TiO ₃ is formed on the lower electrode 17 by sputtering so that the film thickness becomes 1 μm. Next, as shown in FIG. 4C, the composite oxide thin film is patterned into a desired shape by a lift-off method to obtain the dielectric layer 18.
(b) Formation of thin film thermistor A photosensitive resin is formed on the entire upper surface of the SiO ₂ layer 11b, the lower electrode 17 and the dielectric layer 18, and is exposed to light and developed using a predetermined photomask. Is patterned. Next, a thin film having a spinel structure of (Mn _0.4 Co _0.6 ) ₃ O ₄ is formed by a sputtering method so as to have a film thickness of 500 nm. Next, the thin film having the spinel structure is patterned into a desired shape by a lift-off method. The substrate is heat-treated at 800 ° C. for 1 hour to obtain a thin film thermistor 12 having a high resistance value and a highly reliable B constant, as shown in FIG.
(c) Formation of Thin Film Resistor A Ni—Cr thin film is formed on the entire upper surface of the SiO ₂ layer 11b, the lower electrode 17, the dielectric layer 18 and the thin film thermistor 12 by a sputtering method so as to have a film thickness of 500 nm. A photosensitive resin is formed on the entire upper surface of the thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the Ni—Cr thin film is patterned into a desired shape by wet etching using a ferric chloride solution to obtain a thin film resistor 16 as shown in FIG. .
(d) Formation of comb-shaped electrode, upper electrode for thin film capacitor, lead electrode and connection layer Cr thin film is formed on the entire upper surface of SiO ₂ layer 11b, lower electrode 17, dielectric layer 18, thin film thermistor 12 and thin film resistor 16. Is formed by a sputtering method so as to be 100 nm. Subsequently, an Au thin film is formed on the Cr thin film by sputtering so that the film thickness becomes 200 nm. A photosensitive resin is formed on the entire surface of the Au thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the Au thin film is patterned by wet etching using a potassium iodide iodide solution to obtain conductive layers 13b, 14b, 19b, 23b, and 22b of desired electrodes and connection layers (FIG. 2). Subsequently, the Cr thin film is patterned into the same structure as the Au thin film by wet etching using a cerium ammonium nitrate solution to form bonding layers 13a, 14a, 19a, 23a, and 22a (FIG. 2), and FIG. As shown in FIG. 4F, the comb electrodes 13 and 14, the thin film capacitor upper electrode 19, the lead electrodes 23 and 24, and the connection layer 22 are obtained.
(e) Formation of Protective Film After forming various electrodes and connection layers, a SiO ₂ thin film is formed on the entire upper surface of the substrate by sputtering so as to have a film thickness of 600 nm. A photosensitive resin is formed on the entire surface of the SiO ₂ thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the SiO ₂ thin film is patterned by wet etching using hydrofluoric acid, and as shown in FIG. 4G, only the pad portions 17c, 23c, and 24c for connecting lead lines such as lead wires are provided. And all other elements are covered with a protective film 26 made of SiO ₂ . As a result, a thin composite element 10 having a total thickness of 0.25 mm and a length of 3 mm and a width of 2 mm is obtained.

  The manufacturing method of a single composite element has been described above. When mass-producing composite elements, a large number of composite elements composed of thin film thermistors, resistors, and capacitors are formed on a single silicon substrate, and the substrate is cut. Thus, individual thin composite elements are obtained.

<Example 2>
A method of manufacturing the thin composite element shown in FIG. 5 will be described. After turning over the composite element 10 shown in FIG. 4G, a rectangular window 27 is formed by removing the SiO ₂ layer 11d in a portion corresponding to the back side of the thin film thermistor 12 as shown in FIG. 6A. The silicon substrate 11a has an SiO ₂ layer 11b formed on the upper surface and an SiO ₂ layer 11d formed on the lower surface. This window 27 is formed by masking the SiO ₂ layer 11d other than the window portion with a photosensitive resin and patterning the SiO ₂ layer 11d by wet etching using hydrofluoric acid. Subsequently, using the photosensitive resin as a mask, a part of the silicon substrate 11a corresponding to the lower part (upper part in FIG. 6) of the thin film thermistor is etched by wet etching using a tetramethylammonium hydroxide aqueous solution (TMAH). As shown in FIG. 6B, a thin composite element having a thermistor in a membrane structure is obtained.

<Example 3>
A method for manufacturing the thin composite element shown in FIGS. 7 and 8 will be described. First, as shown in FIG. 9A, a SiO ₂ layer 31b having a thickness of 500 nm is formed on a silicon substrate 31a having a thickness of 0.25 mm by a thermal oxidation method.
(a) Formation of Thin Film Thermistor A thin film having a spinel structure of (Mn _0.4 Co _0.6 ) ₃ O ₄ is formed on the entire upper surface of the SiO ₂ layer 31b by a sputtering method so as to have a film thickness of 500 nm. A photosensitive resin is formed on the entire upper surface of the spinel-structured thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the spinel-structured thin film is patterned into a desired shape by wet etching using a diluted hydrochloric acid solution. This substrate is heat-treated at 800 ° C. for 1 hour to obtain a thin film thermistor 32 having a high resistance value and a highly reliable B constant, as shown in FIG. 9B.
(b) Formation of Thin Film Resistor A Ni—Cr thin film is formed on the entire upper surface of the SiO ₂ layer 31b and the thin film thermistor 32 by a sputtering method so as to have a film thickness of 500 nm. A photosensitive resin is formed on the entire upper surface of the thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the Ni—Cr thin film is patterned into a desired shape by wet etching using a ferric chloride solution to obtain a thin film resistor 36 as shown in FIG. 9C. .
(c) Formation of comb-shaped electrode, lower electrode for thin film capacitor, lead electrode and connection layer A thin Cr film is formed on the entire upper surface of the SiO ₂ layer 31b, the thin film thermistor 32 and the thin film resistor 36 by a sputtering method. Form. Subsequently, an Au thin film is formed on the Cr thin film by sputtering so that the film thickness becomes 200 nm. A photosensitive resin is formed on the entire surface of the Au thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the Au thin film is patterned by wet etching using a potassium iodide iodide solution to obtain conductive layers 33b, 34b, 41b, 38b and 37b of desired electrodes and connection layers (FIG. 8). Subsequently, the Cr thin film is patterned into the same structure as the Au thin film by wet etching using a cerium ammonium nitrate solution to form bonding layers 33a, 34a, 41a, 38a and 37a (FIG. 8), and FIG. As shown in FIG. 9D, comb electrodes 33 and 34, a thin film capacitor lower electrode 41, lead electrodes 38 and 39, and a connection layer 37 are obtained.
(d) Formation of protective film After forming various electrodes and connection layers, a SiO ₂ thin film is formed on the entire upper surface of the substrate by sputtering so that the film thickness becomes 600 nm. A photosensitive resin is formed on the entire surface of the SiO ₂ thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the SiO ₂ thin film is patterned by wet etching using hydrofluoric acid, and as shown in FIG. 9E, only the pad portions 38c and 39c for connecting the lead lines such as lead wires are exposed. All other elements are covered with a protective film 42 made of SiO ₂ .
(e) Formation of upper electrode for thin film capacitor In order to form an upper electrode which is a counter electrode of lower electrode 41 for thin film capacitor, a Cr thin film is formed at a predetermined position on the upper surface of protective film 42 so that the film thickness becomes 100 nm. It is formed by a sputtering method. Subsequently, an Au thin film is formed on the Cr thin film by sputtering so that the film thickness becomes 200 nm. A photosensitive resin is formed on the entire surface of the Au thin film, exposed using a predetermined photomask, developed, and patterned. Using the photosensitive resin as a mask, the Au thin film is patterned by wet etching using a potassium iodide iodide solution to obtain a desired conductive layer 43b of the upper electrode 43 (FIG. 8). Subsequently, the Cr thin film is patterned into the same structure as the Au thin film by wet etching using a cerium ammonium nitrate solution to form a bonding layer 43a (FIG. 8), as shown in FIGS. 7 and 9 (f). Then, an upper electrode 43 for a thin film capacitor is obtained. The lower electrode 43, the protective film 42, and the upper electrode 43 form a thin film capacitor 44 (FIG. 8). As a result, a thin composite element 30 having a total thickness of 0.25 mm and a length of 2 mm and a width of 2 mm is obtained.

  The manufacturing method of a single composite element has been described above. When mass-producing composite elements, a large number of composite elements composed of thin film thermistors, resistors, and capacitors are formed on a single silicon substrate, and the substrate is cut. Thus, individual thin composite elements are obtained.

<Example 4>
A method for manufacturing the thin composite element shown in FIG. 10 will be described. After turning over the composite element 30 shown in FIG. 9 (f), a rectangular window 46 is formed by removing the SiO ₂ layer 31 d in the portion corresponding to the back side of the thin film thermistor 32 as shown in FIG. 11 (a). The silicon substrate 31a has an SiO ₂ layer 31b formed on the upper surface and an SiO ₂ layer 31d formed on the lower surface. The window 46 is formed by masking the SiO ₂ layer 31d other than the window portion with a photosensitive resin and patterning the SiO ₂ layer 31d by wet etching using hydrofluoric acid. Subsequently, using the photosensitive resin as a mask, a part of the silicon substrate 31a corresponding to the lower part (upper part in FIG. 11) of the thin film thermistor is etched by wet etching using a tetramethylammonium hydroxide aqueous solution (TMAH). A thin composite element having a thermistor in the membrane structure as shown in FIG.

It is a disassembled perspective view of the thin composite element of 1st Embodiment of this invention. It is the sectional view on the AA line of FIG. 1 of the thin composite element of 1st Embodiment of this invention. It is an equivalent circuit diagram of the thin composite element of the first embodiment of the present invention. It is a perspective view which shows the manufacturing process of the thin composite element of 1st Embodiment of this invention. It is sectional drawing of the thin composite element corresponding to FIG. 2 of 2nd Embodiment of this invention. It is a perspective view which shows the manufacturing process of the thin composite element of 2nd Embodiment of this invention. It is a disassembled perspective view of the thin composite element of 3rd Embodiment of this invention. It is the BB sectional view taken on the line of FIG. 7 of the thin composite element of 3rd Embodiment of this invention. It is a perspective view which shows the manufacturing process of the thin composite element of 3rd Embodiment of this invention. It is sectional drawing of the thin composite element corresponding to FIG. 8 of 4th Embodiment of this invention. It is a perspective view which shows the manufacturing process of the thin composite element of 4th Embodiment of this invention.

Explanation of symbols

10: Thin composite element 11: Insulating substrate 12: Thin film thermistor 13, 14: A pair of comb electrodes 16: Thin film resistor 17: Lower electrode 17a: Bonding layer 17b: Conductive layer 17c: Pad portion 18: Dielectric layer 19: Upper portion Electrode 21: Thin film capacitor 22: Connection layer 23: First extraction electrode 23a: Bonding layer 23b: Conductive layer 23c: Pad part 24: Second extraction electrode 24c: Pad part 26: Protective film 30: Thin composite element 31: Insulating substrate 32: Thin film thermistor 33, 34: A pair of comb-shaped electrodes 36: Thin film resistor 37: Connection layer 37a: Bonding layer 37b: Conductive layer 38: Third extraction electrode 38a: Bonding layer 38b: Conductive layer 38c: Pad portion 39: First 4 extraction electrode 39c: pad part 41: lower electrode 41a: bonding layer 41b: conductive layer 42: protective film 43: upper electrode 3a: bonding layer 43 b: conductive layer 44: thin-film capacitor

Claims (16)

A thin film thermistor, a thin film resistor, and a thin film capacitor are formed on an insulating substrate and separated from each other.
A pair of comb electrodes facing each other is formed on the thin film thermistor,
The thin film capacitor includes a lower electrode formed on the substrate, a dielectric layer formed on the lower electrode, and an upper electrode formed on the dielectric layer,
A connection layer is formed on the substrate so as to electrically connect one of the pair of comb electrodes, one end of the thin film resistor, and one end of the upper electrode or the lower electrode,
A first extraction electrode is formed on the substrate so as to be electrically connected to the other of the pair of comb electrodes;
A second extraction electrode is formed on the substrate to be electrically connected to the other end of the thin film resistor;
A protective film is formed so as to cover all the elements on the substrate except the pad portion for connecting the lead lines in the lower electrode or the upper electrode, the first lead electrode, and the second lead electrode. A thin composite element.   2. The thin composite element according to claim 1, wherein the insulating substrate is a ceramic substrate, a glass substrate, or a silicon substrate having an insulating film on the upper surface of the substrate.   3. The thin composite element according to claim 1, wherein the insulating substrate is a silicon substrate having an insulating film on the upper surface of the substrate, and the cavity or recess of the silicon substrate is formed leaving the insulating film below the thin film thermistor.   A lower electrode, a connection layer, a first extraction electrode, and a second extraction electrode are formed of a bonding layer formed on an insulating substrate and a conductive layer formed on the bonding layer in the same shape and size as the bonding layer. The thin composite element according to any one of claims 1 to 3, each configured. A thin film thermistor, a thin film resistor, and a lower electrode for a thin film capacitor are formed on an insulating substrate so as to be separated from each other.
A pair of comb electrodes facing each other is formed on the thin film thermistor,
A connection layer is formed on the substrate so as to electrically connect one of the pair of comb electrodes, one end of the thin film resistor, and one end of the lower electrode,
A third extraction electrode is formed on the substrate so as to be electrically connected to the other of the pair of comb electrodes;
A fourth extraction electrode is formed on the substrate to be electrically connected to the other end of the thin film resistor;
A protective film made of SiO ₂ is formed so as to cover all the elements on the substrate except the pad portion for connecting the lead lines in the third and fourth lead electrodes;
An upper electrode for a thin film capacitor is formed on the lower electrode through the protective film,
A thin composite element comprising a thin film capacitor composed of the lower electrode, the protective film, and the upper electrode.   6. The thin composite element according to claim 5, wherein the insulating substrate is a ceramic substrate, a glass substrate, or a silicon substrate having an insulating film on the upper surface of the substrate.   The thin composite element according to claim 5 or 6, wherein the insulating substrate is a silicon substrate having an insulating film on the upper surface of the substrate, and the cavity or recess of the silicon substrate is formed leaving the insulating film below the thin film thermistor.   The lower electrode, the connection layer, the third extraction electrode, and the fourth extraction electrode are formed of a bonding layer formed on an insulating substrate and a conductive layer formed on the bonding layer in the same shape and size as the bonding layer. The thin composite element according to any one of claims 5 to 7, each configured. Forming a lower electrode for a thin film capacitor in a predetermined pattern on an insulating substrate;
Forming a dielectric layer on the lower electrode;
Forming a thin film thermistor in a predetermined pattern separately from the lower electrode on the substrate;
Forming a thin film resistor in a predetermined pattern separately from the lower electrode and the thin film thermistor on the substrate;
Forming a pair of opposing comb electrodes on the thin film thermistor and forming an upper electrode for the thin film capacitor on the dielectric layer;
Forming a connection layer on the substrate so as to electrically connect one of the pair of comb electrodes, one end of the thin film resistor, and one end of the upper electrode or the lower electrode;
Forming a first extraction electrode on the substrate so as to be electrically connected to the other of the pair of comb electrodes;
Forming a second extraction electrode on the substrate so as to be electrically connected to the other end of the thin film resistor;
Forming a protective film so as to cover all the elements on the substrate except for a pad portion for connecting lead lines in the lower electrode or the upper electrode, the first lead electrode, and the second lead electrode; A method for manufacturing a thin composite element including:   The method for manufacturing a thin composite element according to claim 9, wherein the insulating substrate is a ceramic substrate, a glass substrate, or a silicon substrate having an insulating film on an upper surface of the substrate.   The thin composite element according to claim 9 or 10, wherein the insulating substrate is a silicon substrate having an insulating film on an upper surface of the substrate, and a cavity or a recess of the silicon substrate is formed by etching using the insulating film as an etching stopper below the thin film thermistor. Manufacturing method.   After the lower electrode, the connection layer, the first extraction electrode, and the second extraction electrode form a bonding layer on the insulating substrate, a conductive layer having the same shape and size as the bonding layer is formed on the bonding layer. The manufacturing method of the thin composite element of any one of Claims 9 thru | or 11 comprised by these. Forming a thin film thermistor in a predetermined pattern on an insulating substrate;
Forming a thin film resistor separately from the thin film thermistor in a predetermined pattern on the substrate;
Forming a pair of opposing comb electrodes on the thin film thermistor;
Forming a connection layer on the substrate so as to electrically connect one of the pair of comb electrodes and one end of the thin film resistor;
Forming a third extraction electrode on the substrate so as to be electrically connected to the other of the pair of comb electrodes;
Forming a fourth extraction electrode on the substrate so as to be electrically connected to the other end of the thin film resistor;
Forming a lower electrode for a thin film capacitor so as to be electrically connected to the connection layer on the substrate;
Forming a protective film made of SiO ₂ so as to cover all elements on the substrate except for the pad portion for connecting the lead lines in the third and fourth lead electrodes;
Forming a thin film capacitor upper electrode on the lower electrode through the protective film.   The method for producing a thin composite element according to claim 13, wherein the insulating substrate is a ceramic substrate, a glass substrate, or a silicon substrate having an insulating film on an upper surface of the substrate.   15. The thin composite element according to claim 13, wherein the insulating substrate is a silicon substrate having an insulating film on the upper surface of the substrate, and a cavity or a recess of the silicon substrate is formed by etching using the insulating film as an etching stopper below the thin film thermistor. Manufacturing method.   After the lower electrode, the connection layer, the third extraction electrode, and the fourth extraction electrode form a bonding layer on the insulating substrate, a conductive layer having the same shape and size as the bonding layer is formed on the bonding layer. The method for manufacturing a thin composite element according to claim 13, comprising:

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