Resistor and method for producing resistor

Abstract

The present disclosure addresses the problem of making it easy to adjust the resistance value of a resistance body. A resistor (1) according to the present disclosure comprises an insulating substrate (11), a resistance body (12), an electrode (13), and an oxynitride film (14). The resistance body (12) contains Cr, Si, and N and is provided on the insulating substrate (11). The electrode (13) contains Cu and / or Ag and is provided on the resistance body (12). The oxynitride film (14) is provided on the resistance body (12). The electrode (13) and the oxynitride film (14) are side by side in a second direction (D2) that is orthogonal to a first direction (D1), which is the thickness direction of the insulating substrate (11). The oxynitride film (14) contacts an end part of the electrode (13) in the second direction (D2).

Description

Resistor and method for manufacturing resistor

[0001] The present disclosure relates generally to resistors and methods of manufacturing resistors, and more particularly to resistors including an insulating substrate and a resistive element disposed on the insulating substrate, and methods of manufacturing resistors.

[0002] Patent Document 1 describes a chip resistor (resistor) including an insulating substrate, a resistor, and a pair of upper electrodes (electrodes). The resistor is provided on the insulating substrate. The pair of upper electrodes are provided at both longitudinal ends of the resistor so as to cover a portion of the upper surface of the resistor.

[0003] In the chip resistor described in Patent Document 1, a resistor is formed on an insulating substrate, and a pair of upper electrodes is formed on the resistor, followed by heat treatment, which may result in the formation of an oxide film on at least one of the pair of upper electrodes, making it difficult to adjust (trim) the resistance value of the resistor by contacting a probe with each of the pair of upper electrodes.

[0004] Japanese Patent Application Laid-Open No. 2020-170843

[0005] An object of the present disclosure is to provide a resistor and a method for manufacturing the resistor that allow the resistance value of the resistor to be easily adjusted.

[0006] A resistor according to one aspect of the present disclosure includes an insulating substrate, a resistive element, an electrode, and an oxynitride film. The resistive element includes Cr, Si, and N and is provided on the insulating substrate. The electrode includes at least one of Cu and Ag and is provided on the resistive element. The oxynitride film is provided on the resistive element. The electrode and the oxynitride film are aligned in a second direction perpendicular to a first direction, which is the thickness direction of the insulating substrate. The oxynitride film is a first oxynitride film, a second oxynitride film, or a third oxynitride film. The first oxynitride film is in contact with an end of the electrode in the second direction. The second oxynitride film has a gap between it and the electrode in the second direction. The third oxynitride film overlaps a portion of the electrode in the first direction.

[0007] A method for manufacturing a resistor according to one aspect of the present disclosure includes a substrate preparation step, a resistor formation step, an oxynitride film formation step, an oxynitride film removal step, and an electrode formation step. In the substrate preparation step, an insulating substrate is prepared. In the resistor formation step, a resistor is formed on the insulating substrate. In the oxynitride film formation step, the resistor formed in the resistor formation step is subjected to a heat treatment to form an oxynitride film on the resistor. In the oxynitride film removal step, at least a portion of the oxynitride film formed in the oxynitride film formation step is removed by etching. In the electrode formation step, an electrode is formed on a portion of the resistor from which the oxynitride film was removed in the oxynitride film removal step.

[0008] FIG. 1 is a cross-sectional view of a resistor according to a first embodiment. FIGS. 2A to 2F are cross-sectional views showing the manufacturing process of the resistor according to the first embodiment. FIGS. 3A to 3C are cross-sectional views showing an oxynitride film removal process among the manufacturing processes of the resistor according to the first embodiment. FIG. 4 is a graph showing the relationship between the analysis depth in the resistor and the quantitative conversion value for the resistor according to the first embodiment. FIG. 5 is a cross-sectional view of a resistor according to a second embodiment. FIG. 6 is a cross-sectional view of a resistor according to a third embodiment. FIGS. 7A to 7F are cross-sectional views showing the manufacturing process of a resistor according to a fourth embodiment. FIG. 8 is a cross-sectional view of a resistor according to a fifth embodiment. FIGS. 9A to 9C are cross-sectional views showing the oxynitride film removal process among the manufacturing processes of a resistor according to a second modification of the first to fifth embodiments.

[0009] Resistors and resistor manufacturing methods according to embodiments 1 to 5 will be described below with reference to the drawings. The drawings described in the following embodiments 1 to 5 are schematic diagrams, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Furthermore, the configurations described in the following embodiments 1 to 5 are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments 1 to 5, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0010] First Embodiment (1) Overview of Resistor First, an overview of a resistor 1 according to a first embodiment will be described with reference to FIG.

[0011] The resistor 1 according to the first embodiment is a surface mount (SMT) chip resistor that is mounted on the surface (mounting surface) of a printed circuit board using a surface mounter, for example. The resistor 1 is also a thin film chip resistor, for example.

[0012] As shown in FIG. 1 , the resistor 1 according to the first embodiment includes an insulating substrate 11, a resistive element 12, a pair of electrodes 13, and an oxynitride film 14. The resistive element 12 contains chromium (Cr), silicon (Si), and nitrogen (N) and is provided on the insulating substrate 11. Each of the pair of electrodes 13 contains at least one of copper (Cu) and silver (Ag) and is provided on the resistive element 12. The oxynitride film 14 is provided on the resistive element 12. The pair of electrodes 13 and the oxynitride film 14 are aligned in a second direction D2. The second direction D2 is a direction perpendicular to the first direction D1, which is the thickness direction of the insulating substrate 11. The oxynitride film 14 is, for example, a first oxynitride film 14. The first oxynitride film 14 is in contact with an end (end surface 131) of the electrode 13 in the second direction D2.

[0013] In the resistor 1 according to the first embodiment, the oxynitride film 14 is not formed on the electrodes 13, so that the measured value is less likely to become unstable when the resistance value of the resistor 12 is measured by contacting a probe with the electrodes 13. As a result, the resistance value of the resistor 12 can be easily adjusted.

[0014] (2) Configuration of Resistor Next, the configuration of the resistor 1 according to the first embodiment will be described with reference to FIG.

[0015] 1, the resistor 1 according to the first embodiment includes an insulating substrate 11, a resistive element 12, a pair of electrodes 13, and an oxynitride film 14. The resistor 1 further includes a protective film 15.

[0016] (2.1) Insulating Substrate The insulating substrate 11 is, for example, a ceramic substrate. The material of the ceramic substrate is, for example, an alumina sintered body with an alumina content of 96% or more. The insulating substrate 11 is formed in a rectangular shape when viewed from a plane in the first direction D1. As shown in FIG. 1 , the insulating substrate 11 has a first main surface (upper surface) 111, a second main surface (lower surface) 112, and an outer peripheral surface 113.

[0017] The first main surface 111 and the second main surface 112 face each other in the first direction D1. Each of the first main surface 111 and the second main surface 112 is a plane extending along a second direction D2 perpendicular to the first direction D1. The outer peripheral surface 113 includes four side surfaces extending along the first direction D1. The first direction D1 is parallel to the thickness direction of the insulating substrate 11 (the up-down direction in FIG. 1 ). The second direction D2 is parallel to the longitudinal direction or width direction (short-side direction) of the insulating substrate 11 (the left-right direction in FIG. 1 ). In the first embodiment, as an example, the second direction D2 is parallel to the longitudinal direction of the insulating substrate 11.

[0018] (2.2) Resistor The resistor 12 is, for example, a thin film, and is provided on the first main surface 111 of the insulating substrate 11. That is, the resistor 12 is provided on the insulating substrate 11. In the example of Fig. 1, the resistor 12 is provided over the entire first main surface 111 of the insulating substrate 11. The resistor 12 has, for example, a rectangular shape when viewed in a plan view from the first direction D1, but can have any shape according to the resistance value of the resistor 12.

[0019] The resistor 12 is made of, for example, an alloy containing Cr, Si, and N. That is, the resistor 12 contains Cr, Si, and N. The atomic ratio of Si to Cr in the resistor 12 is 2 / 3 or more and 4 or less, at least at the center of the resistor 12 in the first direction D1. In other words, the atomic ratio of Cr to Si in the resistor 12 is 3:2 or more and 1:4 or less. Furthermore, the total atomic amount of N in the total atomic amount of metals constituting the resistor 12 is, for example, 50 atomic % or less. That is, the atomic percentage of N in the resistor 12 is 50 atomic % or less, at least at the center of the resistor 12 in the first direction D1 (the film thickness direction of the resistor 12).

[0020] In the resistor 1 according to the first embodiment, the resistive element 12 further contains oxygen (O). The atomic percentage of O in the resistive element 12 is 10 atomic % or less at least at the center of the resistive element 12 in the first direction D1.

[0021] The resistor 12 is formed in a substantially rectangular shape by forming a thin-film conductor over almost the entire surface of the insulating substrate 11 using a thin-film process such as sputtering, and then removing unnecessary portions of the thin-film conductor using a photolithography process.

[0022] The atomic composition ratio of the resistor 12 is calculated from the spectral ratio obtained for each of the elements Cr, Si, N, and O on the top surface or cross section of the resistor 12 using, for example, an energy dispersive X-ray spectroscopy (TEM-EDX) or an electron energy loss spectroscopy (TEX-EELS) attached to a transmission electron microscope (TEM). Alternatively, the atomic composition ratio is calculated by correcting each atomic composition ratio evaluated using X-ray photoelectron spectroscopy (XPS) based on a correction factor for each element evaluated using Rutherford backscattering spectroscopy (RBS).

[0023] Here, it is possible to adjust the resistivity of the resistor 12 by changing the atomic ratio of Cr to Si in the resistor 12. The resistivity of the resistor 12 is preferably 500 μΩ·cm or more and 30,000 μΩ·cm or less.

[0024] (2.3) Electrodes A pair of electrodes 13 is provided on the resistor 12. More specifically, the pair of electrodes 13 is provided so as to cover a portion of the upper surface of the resistor 12 at both ends of the resistor 12 in the longitudinal direction (second direction D2). Each of the pair of electrodes 13 contains at least one of Cu and Ag. In the first embodiment, each of the pair of electrodes 13 contains Cu. Specifically, each of the pair of electrodes 13 is a CuNi (copper-nickel) alloy. In each electrode 13, the atomic percentage of Cu is, for example, 60 atom %. Also, in each electrode 13, the atomic percentage of Ni is, for example, 40 atom %. The pair of electrodes 13 is formed on the portion of the resistor 12 from which the oxynitride film 14 has been removed, for example, by screen printing using a paste material. Each of the pair of electrodes 13 has, for example, a rectangular shape when viewed in a plan view from the first direction D1.

[0025] Each of the pair of electrodes 13 has a pair of end faces 131, 132 and a main surface 133. The pair of end faces 131, 132 face each other in the second direction D2. Each of the pair of end faces 131, 132 is a flat surface extending along the first direction D1. The main surface 133 is the surface of the electrode 13 opposite the resistor 12 side. The main surface 133 is a flat surface extending along the second direction D2. When measuring the resistance value of the resistor 12, a probe is brought into contact with the main surface 133 of each of the pair of electrodes 13.

[0026] (2.4) Oxynitride Film As shown in FIG. 1 , the oxynitride film 14 is provided on the resistor 12. More specifically, the oxynitride film 14 is provided in the central portion of the upper surface of the resistor 12. That is, the oxynitride film 14 is not provided on both end portions of the upper surface of the resistor 12 in the second direction D2. A pair of electrodes 13 is provided on both sides of the oxynitride film 14 in the second direction D2 on the upper surface of the resistor 12. That is, the pair of electrodes 13 and the oxynitride film 14 are aligned in the second direction D2.

[0027] As shown in FIG. 1 , the oxynitride film 14 has a pair of end faces 141. The pair of end faces 141 are both end faces of the oxynitride film 14 in the second direction D2. Each of the pair of end faces 141 is a flat surface along the first direction D1. One of the pair of end faces 141 (the left side in FIG. 1 ) is in contact with the end face 131 of one of the pair of electrodes 13 (the left side in FIG. 1 ). The other of the pair of end faces 141 (the right side in FIG. 1 ) is in contact with the end face 131 of the other of the pair of electrodes 13 (the right side in FIG. 1 ). That is, the oxynitride film 14 is in contact with each end face 131 of the pair of electrodes 13 in the second direction D2. In the resistor 1 according to the first embodiment, the oxynitride film 14 is a first oxynitride film (hereinafter also referred to as the “first oxynitride film 14”). In the resistor 1 according to the first embodiment, the end surface 131 of the electrode 13 is the end of the electrode 13 .

[0028] (2.5) Protective Film The protective film (inorganic protective film) 15 is a film for protecting the resistor 12. The protective film 15 is formed so as to cover at least one of the resistor 12 and the oxynitride film 14. In the example of FIG. 1 , the protective film 15 covers the oxynitride film 14 provided on the resistor 12. In addition, in the example of FIG. 1 , the protective film 15 also covers parts of the pair of electrodes 13 provided on both sides of the oxynitride film 14. That is, in a plan view from the first direction D1, the protective film 15 covers the boundary between the oxynitride film 14 and the pair of electrodes 13, and continuously covers from the oxynitride film 14 to parts of the pair of electrodes 13.

[0029] The protective film 15 is made of, for example, Al ２ O ３ The protective film 15 is made of alumina. For example, the protective film 15 is formed on the entire upper surface of the oxynitride film 14 and on a part of the main surface 133 of the pair of electrodes 13 by applying an alumina paste.

[0030] (3) Method for Manufacturing Resistor Next, a method for manufacturing the resistor 1 according to the first embodiment will be described with reference to FIGS. 2A to 3C.

[0031] The method for manufacturing the resistor 1 according to the first embodiment is a method for manufacturing the above-described resistor 1. The method for manufacturing the resistor 1 includes a substrate preparation step, a resistor formation step, an oxynitride film formation step, an oxynitride film removal step, and an electrode formation step. The method for manufacturing the resistor 1 also includes a protective film formation step. In the method for manufacturing the resistor 1 according to the first embodiment, the substrate preparation step, resistor formation step, oxynitride film formation step, oxynitride film removal step, electrode formation step, and protective film formation step are performed in this order.

[0032] (3.1) Manufacturing Process First, the manufacturing process of the resistor 1 will be described with reference to FIGS. 2A to 2F.

[0033] The substrate preparation step is a step of preparing the insulating substrate 11. More specifically, in the substrate preparation step, as shown in Fig. 2A , for example, the insulating substrate 11 is arranged so that the first main surface 111 is on the upper side and the second main surface 112 is on the lower side.

[0034] The resistor formation step is a step of forming the resistor 12 on the insulating substrate 11. More specifically, in the resistor formation step, the resistor 12 is formed on the first main surface 111 of the insulating substrate 11 by, for example, reactive sputtering in which nitrogen is reacted with the resistor 12, or reactive sputtering in which nitrogen is reacted with oxygen. In the example of Fig. 2B, the resistor 12 is formed over the entire first main surface 111 of the insulating substrate 11. The sputtering target for the reactive sputtering contains, for example, Cr, Si, and O, with an atomic ratio of Cr to Si of 3:7 and an atomic percentage of O of 20 atom %.

[0035] In the resistor formation step, a pattern of the resistor 12 is formed on the insulating substrate 11. More specifically, for example, the pattern of the resistor 12 is formed by removing a part of the resistor 12 using a photolithography process.

[0036] The oxynitride film forming process is a process of performing a heat treatment on the resistor 12 formed in the resistor forming process to form an oxynitride film 16 on the resistor 12. More specifically, as shown in FIG. 2C , the insulating substrate 11 on which the resistor 12 is formed is placed in a heat treatment furnace 100 to perform the heat treatment. As a result, as shown in FIG. 2C , the oxynitride film 16 is formed on the resistor 12. The heat treatment temperature is, for example, 400° C. or higher and 800° C. or lower. In the first embodiment, the heat treatment temperature is, for example, 520° C. In the first embodiment, the heat treatment temperature is the actual temperature of the resistor 12. However, the heat treatment temperature is not limited to the actual temperature of the resistor 12 and may be, for example, an ambient temperature.

[0037] The oxynitride film removing step is a step of removing by etching at least a portion of the oxynitride film 16 formed in the oxynitride film forming step. More specifically, in the oxynitride film removing step, as shown in FIG. 2D , both end portions in the second direction D2 of the oxynitride film 16 formed on the resistor 12 are removed to form the oxynitride film 14. Etching will be described later in the section "(3.2) Etching."

[0038] The electrode formation step is a step of forming electrodes 13 in portions of the resistor 12 from which the oxynitride film 16 has been removed in the oxynitride film removal step. More specifically, in the electrode formation step, a pair of electrodes 13 is formed on both sides of the oxynitride film 14 in the second direction D2 by, for example, screen printing using a paste material, as shown in Fig. 2E . Here, as shown in Fig. 2E , the thickness of each of the pair of electrodes 13 in the first direction D1 is preferably greater than the thickness of the oxynitride film 14 in the first direction D1.

[0039] Here, "forming electrode 13 in the portion of resistor 12 from which oxynitride film 16 has been removed in the oxynitride film removal step" includes both the case where all of electrode 13 is formed in the portion from which oxynitride film 14 has been removed, as described above, and the case where part of electrode 13 (a portion excluding part 134 described below) is formed in the portion from which oxynitride film 16 has been removed, as shown in Fig. 6 described below. In other words, "forming electrode 13 in the portion of resistor 12 from which oxynitride film 16 has been removed in the oxynitride film removal step" means forming at least part of electrode 13 in the portion of resistor 12 from which oxynitride film 16 has been removed in the oxynitride film removal step.

[0040] The protective film forming step is a step of forming the protective film 15 so as to cover at least one of the resistor 12 and the oxynitride film 14. More specifically, in the protective film forming step, the protective film 15 is formed on the entire upper surface of the oxynitride film 14 and on parts of the main surfaces 133 of the pair of electrodes 13 by applying, for example, an alumina paste.

[0041] As a comparative example, consider a case where heat treatment is performed after forming an electrode on a resistor. In this case, the heat treatment temperature is 400°C or higher, so the electrode must be made of a material that is resistant to oxidation corrosion at this heat treatment temperature and does not reduce adhesion to the resistor. This narrows the range of electrode material options.

[0042] In contrast, in the method for manufacturing the resistor 1 according to the first embodiment, a heat treatment is performed on the insulating substrate 11 with only the resistor 12 formed thereon, and after removing a portion of the oxynitride film 16 formed on the resistor 12 by the heat treatment, the electrode 13 is formed on the removed portion. This eliminates concerns about oxidation corrosion of the electrode 13 and a decrease in adhesion to the resistor 12 due to the heat treatment, and has the advantage of increasing the degree of freedom in selecting the electrode material.

[0043] (3.2) Etching Next, the etching in the oxynitride film removal step will be described with reference to FIGS. 3A to 3C. In the first embodiment, the etching in the oxynitride film removal step is dry etching. The dry etching is, for example, reverse sputtering, ion etching, or ion milling. The etching gas is, for example, Ar (argon) gas.

[0044] First, as shown in Fig. 3A, a portion of the oxynitride film 16 formed on the resistor 12 that is to remain as the oxynitride film 14 is masked with a metal mask 200. Next, argon ions are bombarded against the portion of the oxynitride film 16 that is not masked by the metal mask 200. As a result, the portions of the oxynitride film 16 that are not masked by the metal mask 200 (the portions on both sides of the oxynitride film 14 in the second direction D2) are removed (see Fig. 3B).

[0045] Thereafter, a pair of electrodes 13 are formed on both sides of the oxynitride film 14 in the second direction D2 while masked with the metal mask 200. Finally, the metal mask 200 is removed, resulting in the state shown in FIG.

[0046] In the above-described etching, a resist mask may be used instead of the metal mask 200. The metal mask 200 may be removed before the pair of electrodes 13 is formed.

[0047] (4) Resistor Characteristics Next, the characteristics of the resistor 1 according to the first embodiment will be described with reference to FIG. 4 . FIG. 4 shows the results of elemental analysis of a resistor 12 formed (deposited) on a glass substrate. The horizontal axis of FIG. 4 represents the analysis depth in the resistor 12, and the vertical axis of FIG. 4 represents the quantitative equivalent value (atomic percentage) of each element. In the example of FIG. 4 , the atomic ratio of Cr to Si in the resistor 12 is 1:2. In other words, the atomic ratio of Si to Cr in the resistor 12 is 2. In the example of FIG. 4 , the atomic percentage of N in the resistor 12 is 30 atom %. In the example of FIG. 4 , the film thickness of the resistor 12 (the thickness of the resistor 12 in the first direction D1) is 100 nm.

[0048] In the resistor 1 according to the first embodiment, the resistive element 12 contains Cr, Si, N, and O, as described above. The film thickness of the resistive element 12 is 100 nm, as described above. Therefore, in this case, the center of the resistive element 12 in the film thickness direction (first direction D1) is 50 nm. At an analysis depth of 50 nm, the atomic percentage of O in the resistive element 12 is approximately 2 atom % (see the solid line in FIG. 4 ). That is, in the resistor 1 according to the first embodiment, the atomic percentage of O in the resistive element 12 is 10 atom % or less, at least at the center (50 nm) of the resistive element 12 in the first direction D1.

[0049] According to the resistor 1 of the first embodiment, the resistivity of the resistor 12 can be increased by including O in the resistor 12 .

[0050] 4, the atomic percentage of O in the resistor 12 is approximately 2 atom %, but the atomic percentage of O in the resistor 12 may be 10 atom % or less. Also, the atomic percentage of O in the resistor 12 may be 0 atom % or more. In other words, the atomic percentage of O in the resistor 12 may be 0 atom % or more and 10 atom % or less. More preferably, the atomic percentage of O in the resistor 12 is 0.1 atom % or more and 10 atom % or less.

[0051] (5) Effects In the resistor 1 according to the first embodiment, the oxynitride film 14 is not formed on the electrodes 13, so that when a probe is brought into contact with the electrodes 13 to measure the resistance value of the resistor 12, the measured value is less likely to become unstable. As a result, it becomes possible to easily adjust the resistance value of the resistor 12. Furthermore, since the oxynitride film 14 is not formed at the interface between the resistor 12 and the electrodes 13, it is also possible to ensure electrical connection between the resistor 12 and the electrodes 13.

[0052] In the resistor 1 according to the first embodiment, the atomic ratio of Si to Cr in the resistor 12 is 2 / 3 or more and 4 or less at least at the center of the resistor 12 in the first direction D1. Furthermore, the atomic percentage of N in the resistor 12 is 50 atom % or less at least at the center of the resistor 12 in the first direction D1. This makes it possible to achieve both a high resistance ratio and a low TCR.

[0053] In addition, in the resistor 1 according to the first embodiment, by changing the chemical composition of Cr and Si in the resistor 12, it is possible to adjust the resistivity of the resistor 12 within the range of 500 μΩ cm or more and 30,000 μΩ cm or less.

[0054] In the resistor 1 according to the first embodiment, the resistor 12 further contains O. The atomic percentage of O in the resistor 12 is 10 atomic % or less at least at the center of the resistor 12 in the first direction D1. This allows the resistivity of the resistor 12 to be higher than when the resistor 12 does not contain O.

[0055] In the method for manufacturing the resistor 1 according to the first embodiment, the resistor 12 is subjected to a heat treatment to form the oxynitride film 14 on the resistor 12, and then a portion of the oxynitride film 14 is removed. Then, the electrode 13 is formed on the portion of the resistor 12 from which the oxynitride film 14 has been removed. This eliminates concerns about oxidation corrosion of the electrode 13 and a decrease in adhesion to the resistor 12 due to the heat treatment, and has the advantage of increasing the degree of freedom in selecting the electrode material.

[0056] In the method for manufacturing the resistor 1 according to the first embodiment, the etching performed in the oxynitride film removing step is dry etching, which makes it possible to easily remove at least a portion of the oxynitride film 14.

[0057] The method for manufacturing the resistor 1 according to the first embodiment further includes a protective film forming step, in which at least one of the resistor element 12 and the oxynitride film 14 is covered, thereby protecting the resistor element 12.

[0058] Second Embodiment Next, a resistor 1A according to a second embodiment will be described with reference to Fig. 5. In the resistor 1A according to the second embodiment, the same components as those in the resistor 1 according to the first embodiment (see Figs. 1 to 3) are denoted by the same reference numerals, and the description thereof will be omitted.

[0059] The resistor 1A according to the second embodiment differs from the resistor 1 according to the first embodiment in that it includes a second oxynitride film 14A instead of the first oxynitride film 14.

[0060] 5, the resistor 1A according to the second embodiment includes an insulating substrate 11, a resistive element 12, a pair of electrodes 13, and an oxynitride film 14A. The resistor 1A according to the second embodiment further includes a protective film 15.

[0061] The oxynitride film 14A is provided on the resistor 12. A pair of electrodes 13 is also provided on the resistor 12. The pair of electrodes 13 and the oxynitride film 14A are aligned in the second direction D2. In other words, the pair of electrodes 13 are provided on both sides of the oxynitride film 14A in the second direction D2. A gap G1 is provided between each of the pair of electrodes 13 and the oxynitride film 14A. That is, the oxynitride film 14A is a second oxynitride film (hereinafter also referred to as the "second oxynitride film 14A") that has a gap G1 between itself and each of the pair of electrodes 13 in the second direction D2. Therefore, each of the end faces 141 of the second oxynitride film 14A is not in contact with the end face 131 of the corresponding one of the pair of electrodes 13.

[0062] 5, a part of the resistor 12 (a part of the resistor 12 corresponding to the gap G1) is exposed in the resistor 1A according to the second embodiment. Therefore, in the resistor 1A according to the second embodiment, the protective film 15 covers both the resistor 12 and the oxynitride film 14A.

[0063] In the resistor 1A according to the second embodiment, the oxynitride film 14A is not formed on the electrode 13, so that the measured value is less likely to become unstable when the resistance value of the resistor 12 is measured by contacting a probe with the electrode 13. As a result, it becomes possible to easily adjust the resistance value of the resistor 12. Furthermore, since the oxynitride film 14A is not formed at the interface between the resistor 12 and the electrode 13, it is also possible to ensure electrical connection between the resistor 12 and the electrode 13.

[0064] Third Embodiment Next, a resistor 1B according to a third embodiment will be described with reference to Fig. 6. In the resistor 1B according to the third embodiment, the same components as those in the resistor 1 according to the first embodiment (see Figs. 1 to 3) are denoted by the same reference numerals, and the description thereof will be omitted.

[0065] The resistor 1B according to the third embodiment differs from the resistor 1 according to the first embodiment in that it includes a third oxynitride film 14B instead of the first oxynitride film 14.

[0066] 6, the resistor 1B according to the third embodiment includes an insulating substrate 11, a resistive element 12, a pair of electrodes 13, and an oxynitride film 14B. The resistor 1B according to the third embodiment further includes a protective film 15.

[0067] The oxynitride film 14B is provided on the resistor 12. A pair of electrodes 13 is provided on the resistor 12. The pair of electrodes 13 and the oxynitride film 14B are aligned in the second direction D2. In other words, the pair of electrodes 13 are provided on both sides of the oxynitride film 14B in the second direction D2. Each of the pair of electrodes 13 has a portion (extension) 134. The portion 134 extends toward the oxynitride film 14B in the second direction D2. As a result, the portion 134 of each of the pair of electrodes 13 overlaps with the portion 134 of the oxynitride film 14B in the first direction D1. That is, in the resistor 1B according to the third embodiment, the oxynitride film 14B is a third oxynitride film (hereinafter also referred to as the "third oxynitride film 14B").

[0068] In the resistor 1B according to the third embodiment, similarly to the resistor 1 according to the first embodiment, the protective film 15 covers the oxynitride film 14B provided on the resistive element 12. In the resistor 1B according to the third embodiment, the protective film 15 also covers a part of the pair of electrodes 13 provided on both sides of the oxynitride film 14B.

[0069] In the resistor 1B according to the third embodiment, the oxynitride film 14B is not formed on the electrode 13, so that the measured value is less likely to become unstable when the resistance value of the resistor 12 is measured by contacting a probe with the electrode 13. As a result, it becomes possible to easily adjust the resistance value of the resistor 12. Furthermore, since the oxynitride film 14B is not formed on the interface between the resistor 12 and the electrode 13, it is also possible to ensure electrical connection between the resistor 12 and the electrode 13.

[0070] 7A to 7F, a resistor 1C according to a fourth embodiment and a method for manufacturing the resistor 1C will be described. In the resistor 1C according to the fourth embodiment, the same components as those in the resistor 1 according to the first embodiment (see FIGS. 1 to 3) are designated by the same reference numerals, and the description thereof will be omitted.

[0071] The resistor 1C according to the fourth embodiment differs from the resistor 1 according to the first embodiment in that it does not include an oxynitride film.

[0072] 7F, the resistor 1C according to the fourth embodiment includes an insulating substrate 11, a resistor element 12, a pair of electrodes 13, and a protective film 15. That is, in the resistor 1C according to the fourth embodiment, the oxynitride film 16 formed on the resistor element 12 in the oxynitride film forming step is entirely removed (see FIG. 7D).

[0073] The method for manufacturing the resistor 1C according to the fourth embodiment includes a substrate preparation step, a resistor formation step, an oxynitride film formation step, an oxynitride film removal step, and an electrode formation step. The method for manufacturing the resistor 1C according to the fourth embodiment also includes a protective film formation step. In the method for manufacturing the resistor 1C according to the fourth embodiment, the substrate preparation step, resistor formation step, oxynitride film formation step, oxynitride film removal step, electrode formation step, and protective film formation step are performed in this order.

[0074] In the substrate preparation step, as shown in FIG. 7A, for example, the insulating substrate 11 is arranged so that the first main surface 111 faces upward and the second main surface 112 faces downward.

[0075] In the resistor formation step, as shown in FIG. 7B, the resistor 12 is formed over the entire first main surface 111 of the insulating substrate 11 using a thin film process such as sputtering.

[0076] In the oxynitride film forming step, as shown in FIG. 7C , the insulating substrate 11 on which the resistor 12 is formed is placed in a heat treatment furnace 100 and heat treated to form an oxynitride film 16 over the entire surface of the resistor 12 (the upper surface in FIG. 7C ).

[0077] In the oxynitride film removal step, the oxynitride film 16 is removed by, for example, dry etching. In the example of Fig. 7D, the oxynitride film 16 is completely removed in the oxynitride film removal step. That is, after the oxynitride film removal step is performed, the oxynitride film does not exist.

[0078] In the electrode formation step, as shown in FIG. 7E, a pair of electrodes 13 are formed on both ends of the resistor 12 in the second direction D2 by, for example, screen printing using a paste material.

[0079] Finally, in the protective film forming step, as shown in FIG. 7F, a protective film 15 is formed by applying, for example, an alumina paste so as to cover a portion of each of the resistor 12 and the pair of electrodes 13 .

[0080] In the resistor 1C according to the fourth embodiment, an oxynitride film is not formed on the electrodes 13, so that the measured value is less likely to become unstable when the resistance value of the resistor 12 is measured by contacting a probe with the electrodes 13. As a result, it becomes possible to easily adjust the resistance value of the resistor 12. Furthermore, since an oxynitride film is not formed on the interface between the resistor 12 and the electrodes 13, it is also possible to ensure electrical connection between the resistor 12 and the electrodes 13.

[0081] Furthermore, in the manufacturing method of the resistor 1C according to the fourth embodiment, the insulating substrate 11 on which only the resistor element 12 is formed is subjected to a heat treatment to form the oxynitride film 16 on the resistor element 12. Then, after the oxynitride film 16 on the resistor element 12 is completely removed, the pair of electrodes 13 is formed on the resistor element 12. This eliminates concerns about oxidation corrosion of the electrodes 13 and a decrease in adhesion to the resistor element 12 due to the heat treatment, and has the advantage of increasing the degree of freedom in selecting the electrode material.

[0082] Fifth Embodiment Next, a resistor 1D according to a fifth embodiment will be described with reference to Fig. 8. In the resistor 1D according to the fifth embodiment, the same components as those in the resistor 1 according to the first embodiment (see Figs. 1 to 3) are denoted by the same reference numerals, and the description thereof will be omitted.

[0083] The resistor 1D according to the fifth embodiment differs from the resistor 1 according to the first embodiment in that it further includes a second protective film 17 that is different from the protective film 15 (hereinafter also referred to as the "first protective film 15"). The resistor 1D according to the fifth embodiment also differs from the resistor 1 according to the first embodiment in that it further includes a pair of end electrodes 18, a pair of plating layers 19, and a pair of back electrodes 20.

[0084] 8 , the resistor 1D according to the fifth embodiment includes an insulating substrate 11, a resistive element 12, a pair of electrodes 13 (hereinafter also referred to as a pair of upper electrodes 13), an oxynitride film 14A, and a first protective film 15. The resistor 1D further includes a second protective film 17, a pair of end electrodes 18, a pair of plating layers 19, and a pair of back electrodes 20.

[0085] The oxynitride film 14A is, for example, a second oxynitride film (hereinafter also referred to as "second oxynitride film 14A") that has a gap G1 between itself and each of the pair of electrodes 13 in the second direction D2.

[0086] The second protective film (resin protective film) 17 is made of, for example, epoxy resin and covers the entire first protective film 15 and a portion of the pair of upper surface electrodes 13. That is, in a plan view from the first direction D1, the second protective film 17 covers the boundary between the first protective film 15 and the pair of upper surface electrodes 13 and continuously covers from the first protective film 15 to at least a portion of the pair of upper surface electrodes 13.

[0087] The second protective film 17 is formed by, for example, applying an epoxy resin by screen printing and then curing the epoxy resin by irradiating it with ultraviolet light. Note that the portions of the pair of upper electrodes 13 that are located between both ends (portions covering the pair of upper electrodes 13) of the first protective film 15 in the longitudinal direction (second direction D2) and the plating layer 19 are directly covered with the second protective film 17.

[0088] Each of the pair of end electrodes 18 is made of, for example, a CuNi alloy. The pair of end electrodes 18 is located at both ends of the insulating substrate 11 in the longitudinal direction (second direction D2). The pair of end electrodes 18 is formed at both ends of the insulating substrate 11 in the longitudinal direction using, for example, a thin-film process such as sputtering. The pair of end electrodes 18 is electrically connected to the pair of top electrodes 13.

[0089] 8 , each of the pair of plating layers 19 includes a Ni plating layer 191 and a Sn plating layer 192. Each of the pair of plating layers 19 is connected to a part of the corresponding one of the pair of upper surface electrodes 13, and is in contact with the second protective film 17. In addition, each of the pair of plating layers 19 covers the corresponding one of the pair of end surface electrodes 18.

[0090] Each of the pair of back electrodes 20 is made of, for example, epoxy resin containing Ag (silver) as a conductive material. The pair of back electrodes 20 is located at both ends of the second main surface 112 of the insulating substrate 11 in the longitudinal direction (second direction D2). The pair of back electrodes 20 is formed, for example, by applying epoxy resin to both ends of the second main surface 112 of the insulating substrate 11 in the longitudinal direction by screen printing, and then irradiating the epoxy resin with ultraviolet light to harden it. The pair of back electrodes 20 corresponds one-to-one to the pair of upper surface electrodes 13. Note that the pair of back electrodes 20 may be omitted.

[0091] In the resistor 1D according to the fifth embodiment, the oxynitride film 14 is not formed on the top electrode 13, so that the measured value is less likely to be unstable when the resistance value of the resistor 12 is measured by contacting a probe with the top electrode 13. As a result, it becomes possible to easily adjust the resistance value of the resistor 12. Furthermore, since the oxynitride film 14 is not formed on the interface between the resistor 12 and the top electrode 13, it is also possible to ensure electrical connection between the resistor 12 and the top electrode 13.

[0092] In addition, the oxynitride film 14A is not limited to the second oxynitride film, but may be, for example, a first oxynitride film in contact with the end of the electrode 13 in the second direction D2, or a third oxynitride film overlapping a portion of the electrode 13 in the first direction D1.

[0093] (Modifications) Embodiments 1 to 5 are merely one of various embodiments of the present disclosure. Various modifications of Embodiments 1 to 5 can be made depending on the design, etc., as long as the object of the present disclosure can be achieved. Modifications of Embodiments 1 to 5 are listed below. The modifications described below can be applied in appropriate combinations.

[0094] (1) Modification 1 In the first to fifth embodiments, the resistor 12 contains Cr, Si, N, and O. However, the resistor 12 may contain Al (aluminum) in addition to Cr, Si, N, and O. That is, in the resistor 1 according to Modification 1, the resistor 12 further contains Al. The atomic percentage of Al in the resistor 12 is 30 atomic % or less at least at the center of the resistor 12 in the first direction D1 (the film thickness direction of the resistor 12).

[0095] In the resistor 1 according to the first modification, the resistive element 12 contains Al in addition to Cr, Si, N, and O. This allows the resistivity of the resistive element 12 to be higher than when the resistive element 12 does not contain Al.

[0096] (2) Modification 2 In the first to fifth embodiments, the etching in the oxynitride film removal step is dry etching, but the etching is not limited to dry etching and may be wet etching. Wet etching will be described below with reference to FIGS. 9A to 9C.

[0097] 9A, in the wet etching, the insulating substrate 11 having the oxynitride film 16 formed on the resistor 12 is immersed in a solution 500 contained in a container 400. The solution 500 is a solution that reacts with the oxynitride film 16, such as hydrofluoric acid.

[0098] 9A , in order to leave the oxynitride film 14 located in the central portion of the oxynitride film 16, the corresponding portion is masked with a resist mask 300. As a result, the portion of the oxynitride film 16 that is not masked with the resist mask 300 reacts with the solution 500 and is removed. As a result, the portion of the oxynitride film 16 that is masked with the resist mask 300 becomes the oxynitride film 14, as shown in FIG.

[0099] 9B, a pair of electrodes 13 are formed on both sides of the oxynitride film 14 in the second direction D2. Then, the resist mask 300 is removed, resulting in the state shown in FIG.

[0100] (3) Other Modifications Other modifications are listed below.

[0101] In the first to fifth embodiments, the resistor 12 contains O, but the resistor 12 does not necessarily contain O. In other words, the resistor 12 only needs to contain at least Cr, Si, and N.

[0102] In the first to fifth embodiments, each of the pair of electrodes 13 contains Cu, but each of the pair of electrodes 13 may contain, for example, Ag, or both Cu and Ag. That is, it is sufficient that each of the pair of electrodes 13 contains at least one of Cu and Ag.

[0103] When each of the pair of electrodes 13 contains Ag, each of the pair of electrodes 13 is, for example, an AgPd alloy. The atomic percentage of Ag in each electrode 13 is, for example, 97 atom %. The atomic percentage of Pd in ​​each electrode 13 is, for example, 3 atom %.

[0104] Furthermore, when each of the pair of electrodes 13 contains both Cu and Ag, each of the pair of electrodes 13 is, for example, an AgCuPd alloy. In each electrode 13, the atomic percentage of Ag is, for example, 98 atom %. In each electrode 13, the atomic percentage of Cu is, for example, 1 atom %. In each electrode 13, the atomic percentage of Pd is, for example, 1 atom %.

[0105] In the first to fifth embodiments, the resistor 12 is formed using a thin film process such as sputtering, but the resistor 12 may also be formed using, for example, a resistor paste.

[0106] In the first to fifth embodiments, the pair of electrodes 13 is formed by screen printing using a paste material, but the pair of electrodes 13 may also be formed using a thin film process such as sputtering.

[0107] (Aspects) The present specification discloses the following aspects.

[0108] A resistor (1; 1A; 1B; 1C; 1D) according to a first aspect includes an insulating substrate (11), a resistor (12), an electrode (13), and an oxynitride film (14; 14A; 14B). The resistor (12) contains Cr, Si, and N and is provided on the insulating substrate (11). The electrode (13) contains at least one of Cu and Ag and is provided on the resistor (12). The oxynitride film (14; 14A; 14B) is provided on the resistor (12). The electrode (13) and the oxynitride film (14; 14A; 14B) are aligned in a second direction (D2) perpendicular to a first direction (D1) that is the thickness direction of the insulating substrate (11). The oxynitride film (14; 14A; 14B) is a first oxynitride film (14), a second oxynitride film (14A), or a third oxynitride film (14B). The first oxynitride film (14) is in contact with an end (131) of the electrode (13) in the second direction (D2). The second oxynitride film (14A) has a gap (G1) between it and the electrode (13) in the second direction (D2). The third oxynitride film (14B) overlaps a portion (134) of the electrode (13) in the first direction (D1).

[0109] According to this embodiment, since no oxynitride film (14; 14A; 14B) is formed on the electrode (13), the measured value is less likely to be unstable when the resistance value of the resistor (12) is measured by contacting a probe with the electrode (13). As a result, the resistance value of the resistor (12) can be easily adjusted.

[0110] In the resistor (1; 1A; 1B; 1C; 1D) according to the second aspect, the atomic ratio of Si to Cr in the resistor (12) is 2 / 3 or more and 4 or less at least at the center of the resistor (12) in the first direction (D1). The atomic percentage of N in the resistor (12) is 50 atom % or less at least at the center of the resistor (12) in the first direction (D1).

[0111] According to this embodiment, it is possible to achieve both a high resistance ratio and a low TCR.

[0112] In the resistor (1; 1A; 1B; 1C; 1D) according to the third aspect, in the first or second aspect, the resistivity of the resistor (12) is 500 μΩ·cm or more and 30,000 μΩ·cm or less.

[0113] According to this embodiment, it is possible to adjust the resistivity of the resistor (12).

[0114] In a resistor (1; 1A; 1B; 1C; 1D) according to a fourth aspect, in any one of the first to third aspects, the resistor (12) further contains Al, and the atomic percentage of Al in the resistor (12) is 30 atom % or less at least at the center of the resistor (12) in the first direction (D1).

[0115] According to this embodiment, it is possible to increase the resistivity of the resistor (12) compared to when the resistor (12) does not contain Al.

[0116] In a resistor (1; 1A; 1B; 1C; 1D) according to a fifth aspect, in any one of the first to fourth aspects, the resistor (12) further contains O. The atomic percentage of O in the resistor (12) is 10 atom % or less at least at the center of the resistor (12) in the first direction (D1).

[0117] According to this embodiment, it is possible to increase the resistivity of the resistor (12) compared to when the resistor (12) does not contain O.

[0118] A method for manufacturing a resistor (1; 1A; 1B; 1C; 1D) according to a sixth aspect includes a resistor formation step, an oxynitride film formation step, an oxynitride film removal step, and an electrode formation step. In the resistor formation step, a resistor (12) is formed on an insulating substrate (11). In the oxynitride film formation step, the resistor (12) formed in the resistor formation step is subjected to heat treatment to form an oxynitride film (16) on the resistor (12). In the oxynitride film removal step, the oxynitride film (16) formed in the oxynitride film formation step is etched to remove at least a portion of the oxynitride film (16). In the electrode formation step, an electrode (13) is formed on a portion of the resistor (12) from which the oxynitride film (16) was removed in the oxynitride film removal step.

[0119] According to this embodiment, since no oxynitride film (14; 14A; 14B) is formed on the electrode (13), the resistance value of the resistor (12) is less likely to become unstable when the resistance value of the resistor (12) is measured by contacting a probe with the electrode (13), which makes it possible to easily adjust the resistance value of the resistor (12).

[0120] In the method for manufacturing a resistor (1; 1A; 1B; 1C; 1D) according to a seventh aspect, in the sixth aspect, the etching is dry etching.

[0121] According to this aspect, it is possible to remove at least a part of the oxynitride film (14; 14A; 14B).

[0122] In the method for manufacturing a resistor (1; 1A; 1B; 1C; 1D) according to an eighth aspect, in the sixth aspect, the etching is wet etching.

[0123] According to this aspect, it is possible to remove at least a part of the oxynitride film (14; 14A; 14B).

[0124] A method for manufacturing a resistor (1; 1A; 1B; 1C; 1D) according to a ninth aspect is any one of the sixth to eighth aspects, further comprising a protective film forming step in which a protective film (15) is formed so as to cover the resistor (12).

[0125] According to this aspect, the resistor (12) can be protected by the protective film (15).

[0126] The configurations according to the second to fifth aspects are not essential for the resistors (1; 1A; 1B; 1C; 1D) and can be omitted as appropriate.

[0127] The configurations according to the seventh to ninth aspects are not essential for the manufacturing method of the resistor (1; 1A; 1B; 1C; 1D), and can be omitted as appropriate.

[0128] 1, 1A, 1B, 1C, 1D Resistors 11 Insulating substrate 12 Resistors 13 Electrodes 14 First oxide film (oxide film) 14A Second oxide film (oxide film) 14B Third oxide film (oxide film) 15 Protective film 16 Oxygen film 131, 132 End faces (ends) 134 Part D1 First direction D2 Second direction G1 Gap

Claims

1. An insulating substrate, a resistor containing Cr, Si, and N, provided on the insulating substrate, an electrode containing at least one of Cu and Ag, provided on the resistor, and a silicon oxynitride film provided on the resistor, wherein the electrode and the silicon oxynitride film are arranged side by side in a second direction orthogonal to a first direction which is the thickness direction of the insulating substrate, the silicon oxynitride film is a first silicon oxynitride film in contact with an end portion of the electrode in the second direction, a second silicon oxynitride film having a gap between the second silicon oxynitride film and the electrode in the second direction, or a third silicon oxynitride film in which a part of the electrode overlaps in the first direction, a resistor.

2. The atomic ratio of Si to Cr in the resistor is 2 / 3 or more and 4 or less at least at the center of the resistor in the first direction, and the atomic percentage of N in the resistor is 50 atom% or less at least at the center of the resistor in the first direction, The resistor according to claim 1.

3. The specific resistance of the resistor is 500 μΩ·cm or more and 30000 μΩ·cm or less, The resistor according to claim 1 or 2.

4. The resistor further contains Al, and the atomic percentage of Al in the resistor is 30 atom% or less at least at the center of the resistor in the first direction, The resistor according to claim 1 or 2.

5. The resistor further contains O, and the atomic percentage of O in the resistor is 10 atom% or less at least at the center of the resistor in the first direction, The resistor according to claim 1 or 2.

6. A substrate preparation step of preparing an insulating substrate, a resistor formation step of forming a resistor on the insulating substrate, a silicon oxynitride film formation step of performing heat treatment on the resistor formed in the resistor formation step to form a silicon oxynitride film on the resistor, a silicon oxynitride film removal step of removing at least a part of the silicon oxynitride film formed in the silicon oxynitride film formation step by etching, and an electrode formation step of forming an electrode on a portion of the resistor from which the silicon oxynitride film has been removed in the silicon oxynitride film removal step, A method for manufacturing a resistor.

7. The etching is dry etching, The method for manufacturing a resistor according to claim 6.

8. The etching is wet etching, The method for manufacturing a resistor according to claim 6.

9. Further having a protective film forming step of forming a protective film so as to cover at least one of the resistor and the oxynitride film, The method of manufacturing a resistor according to any one of claims 6 to 8.