Electronic components

Abstract

This electronic component comprises an element body (20), and a glass film (50) which covers an outer surface (21) of the element body (20). The glass film (50) has a groove (52) that extends on an outer surface (51) of the glass film (50). The groove (52) is recessed from the outer surface (51) of the glass film (50) toward the outer surface (21) side of the element body (20) in a specific cross-section in a direction orthogonal to the outer surface (51) of the glass film (50). A bottom (52A) of the groove (52) is positioned closer to the outer surface (51) side of the glass film (50) than the outer surface (21) of the element body (20). In addition, the bottom (52A) of the groove (52) has an arc shape in the specific cross section.

Description

[Technical Field]

[0001] The present disclosure relates to an electronic component. [Background Art]

[0002] The invention described in Patent Document 1 includes an element body, an internal electrode, a glass layer, and an external electrode. The internal electrode is located inside the element body. The glass layer covers a surface of the element body. The glass layer has a plurality of through holes. The through holes extend from an outer surface of the glass layer to a boundary between the glass layer and the element body. The external electrode is laminated on the outer surface of the glass layer. Further, the external electrode is electrically connected to the internal electrode. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent No. 6680075 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] In an electronic component such as the invention described in Patent Document 1, basically, the greater the thickness of the glass layer, the greater the stress of the glass layer. On the other hand, when the glass layer has through holes as described in Patent Document 1, the stress in the glass layer is released at the through holes. Therefore, in the above electronic component, stress concentration at a specific portion of the glass layer can be suppressed. However, in the electronic component described in Patent Document 1, since the glass layer has through holes, the barrier property of the glass layer is reduced. Accordingly, there is a need for a structure that can relieve stress in the glass layer while suppressing a decrease in the barrier property of the glass layer. [Means for Solving the Problem]

[0005] To solve the above problems, one aspect of the present disclosure is an electronic component comprising a base body and a glass film covering the outer surface of the base body, wherein the glass film extends on the outer surface of the glass film and has a groove in a specific cross section in a direction perpendicular to the outer surface of the glass film that is recessed from the outer surface of the glass film toward the outer surface of the base body, the bottom of the groove is located on the outer surface side of the glass film than the outer surface of the base body, and the bottom of the groove is arc-shaped in the specific cross section. [Effects of the Invention]

[0006] According to the above configuration, it is possible to suppress stress concentration in the glass film while ensuring the barrier properties of the glass film. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a perspective view of an electronic component. [Figure 2] Figure 2 is a side view of an electronic component. [Figure 3] Figure 3 is a cross-sectional view along the line 3-3 in Figure 2. [Figure 4] Figure 4 is a magnified view of the outer surface of the glass film of an electronic component. [Figure 5] Figure 5 is a magnified view of the vicinity of the glass film when an electronic component is viewed in a specific cross-section. [Figure 6] Figure 6 is an explanatory diagram illustrating the manufacturing method of electronic components. [Figure 7] Figure 7 is an explanatory diagram illustrating the manufacturing method of electronic components. [Figure 8] Figure 8 is an explanatory diagram illustrating the manufacturing method of electronic components. [Figure 9] Figure 9 is an explanatory diagram illustrating the manufacturing method of electronic components. [Figure 10] Figure 10 is an explanatory diagram illustrating the manufacturing method of electronic components. [Figure 11] Figure 11 is an explanatory diagram illustrating the manufacturing method of electronic components. [Figure 12] Figure 12 is an explanatory diagram illustrating the manufacturing method of electronic components. [Figure 13] Figure 13 is a magnified view of the vicinity of the glass film in a specific cross-sectional view of the modified electronic component. [Modes for carrying out the invention]

[0008] <An embodiment of an electronic component> An embodiment of an electronic component will be described below with reference to the drawings. Note that the drawings may show components enlarged for ease of understanding. The dimensional ratios of the components may differ from those in the actual components or those shown in other drawings.

[0009] <About the overall structure> As shown in Figure 1, the electronic component 10 is a surface-mount type negative-resistance thermistor component that is mounted on a circuit board or the like. A negative-resistance thermistor component has the characteristic that its resistance decreases as the temperature rises.

[0010] The electronic component 10 comprises a base body 20. The base body 20 is roughly rectangular in shape and has a central axis CA. In the following, the axis extending along the central axis CA will be referred to as the first axis X. One of the axes perpendicular to the first axis X will be referred to as the second axis Y. The axis perpendicular to both the first axis X and the second axis Y will be referred to as the third axis Z. Furthermore, one direction along the first axis X will be referred to as the first positive direction X1, and the direction along the first axis X opposite to the first positive direction X1 will be referred to as the first negative direction X2. Furthermore, one direction along the second axis Y will be referred to as the second positive direction Y1, and the direction along the second axis Y opposite to the second positive direction Y1 will be referred to as the second negative direction Y2. Furthermore, one direction along the third axis Z will be referred to as the third positive direction Z1, and the direction along the third axis Z opposite to the third positive direction Z1 will be referred to as the third negative direction Z2.

[0011] An outer surface 21 of the base body 20 has six flat surfaces. The "surface" of the base body 20 as used herein refers to a surface that can be observed as a surface when the entire base body 20 is observed. That is, even if there are fine irregularities or steps that can only be identified by magnifying and observing a part of the base body 20 with a microscope or the like, the surface is expressed as a flat surface or a curved surface. The six flat surfaces face mutually different directions. The six flat surfaces are broadly classified into a first end surface 22A facing the first positive direction X1, a second end surface 22B facing the first negative direction X2, and four side surfaces 22C. The four side surfaces 22C are respectively a surface facing the third positive direction Z1, a surface facing the third negative direction Z2, a surface facing the second positive direction Y1, and a surface facing the second negative direction Y2.

[0012] In the outer surface 21 of the base body 20, a boundary portion between two adjacent flat surfaces and a boundary portion between three adjacent flat surfaces are curved surfaces. That is, the corners of the base body 20 have a rounded chamfer shape. In FIGS. 1 and 2, the surface of a glass film 50 described later is regarded as the same as the outer surface 21 of the base body 20 when reference numerals are assigned.

[0013] As shown in FIG. 2, the dimension of the base body 20 along the first axis X is larger than the dimension along the third axis Z. Further, as shown in FIG. 1, the dimension of the base body 20 along the first axis X is larger than the dimension along the second axis Y. The base body 20 is made of ceramics obtained by firing a metal oxide containing one or more components selected from Mn, Fe, Ni, Co, Ti, Ba, Al, and Zn.

[0014] As shown in FIG. 3, the electronic component 10 includes two first internal electrodes 41 and two second internal electrodes 42. The first internal electrodes 41 and the second internal electrodes 42 are embedded inside the base body 20.

[0015] The first internal electrode 41 is made of a conductive material. For example, the material of the first internal electrode 41 is palladium. The material of the second internal electrode 42 is the same as the material of the first internal electrode 41.

[0016] The first internal electrode 41 has a rectangular plate shape. The main surface of the first internal electrode 41 is perpendicular to the second axis Y. The second internal electrode 42 has the same rectangular plate shape as the first internal electrode 41. The main surface of the second internal electrode 42 is perpendicular to the second axis Y, similar to the first internal electrode 41.

[0017] The dimension of the first internal electrode 41 in the direction along the first axis X is smaller than the dimension of the base body 20 in the direction along the first axis X. Also, as shown in Figure 1, the dimension of the first internal electrode 41 in the direction along the third axis Z is approximately two-thirds of the dimension of the base body 20 in the direction along the third axis Z. The dimensions of the second internal electrode 42 in each direction are the same as those of the first internal electrode 41.

[0018] As shown in Figure 3, the first internal electrode 41 and the second internal electrode 42 are positioned alternately in the direction along the second axis Y. That is, they are arranged in the order of first internal electrode 41, second internal electrode 42, first internal electrode 41, second internal electrode 42, from the side surface 22C facing the second positive direction Y1 toward the second negative direction Y2. In this embodiment, the distance between each internal electrode in the direction along the second axis Y is equal.

[0019] As shown in Figure 1, the two first internal electrodes 41 and the two second internal electrodes 42 are all located in the center of the body 20 in the direction along the third axis Z. On the other hand, as shown in Figure 3, the first internal electrodes 41 are located towards the first positive direction X1, and the second internal electrodes 42 are located towards the first negative direction X2.

[0020] Specifically, the first positive X1 end of the first internal electrode 41 coincides with the first positive X1 end of the base body 20. The first negative X2 end of the first internal electrode 41 is located inside the base body 20 and does not reach the first negative X2 end of the base body 20. On the other hand, the first negative X2 end of the second internal electrode 42 coincides with the first negative X2 end of the base body 20. The first positive X1 end of the second internal electrode 42 is located inside the base body 20 and does not reach the first positive X1 end of the base body 20.

[0021] As shown in Figure 3, the electronic component 10 is equipped with a glass film 50. The glass film 50 covers the outer surface 21 of the base body 20. In this embodiment, the glass film 50 covers all areas of the outer surface 21 of the base body 20. The main material of the glass film 50 is insulating glass. Therefore, the glass film 50 contains silicon dioxide. In addition, the glass film 50 contains one or more elements selected from alkali metals and alkaline earth metals as additives. Specifically, the glass film 50 contains potassium as an additive. Therefore, in the elemental mapping image of the cross-sectional image of the glass film 50, the glass film 50 may have an interface due to the presence of potassium.

[0022] The electronic component 10 comprises a first external electrode 61 and a second external electrode 62. The first external electrode 61 has a first base electrode 61A and a first metal layer 61B. The first base electrode 61A is laminated on top of the glass film 50 on a portion of the outer surface 21 of the base body 20, including the first end face 22A. Specifically, the first base electrode 61A is a five-sided electrode that covers the first end face 22A of the base body 20 and a portion of the first positive direction X1 side of the four side surfaces 22C. In this embodiment, the material of the first base electrode 61A is silver and glass.

[0023] The first metal layer 61B covers the first base electrode 61A from the outside. Therefore, the first metal layer 61B is laminated on the first base electrode 61A. Although not shown in the diagram, the first metal layer 61B has a two-layer structure consisting of a nickel layer and a tin layer, in that order from the side of the first base electrode 61A.

[0024] The second external electrode 62 has a second base electrode 62A and a second metal layer 62B. The second base electrode 62A is laminated on top of the glass film 50 on a portion of the outer surface 21 of the base body 20, including the second end face 22B. Specifically, the second base electrode 62A is a five-sided electrode that covers the second end face 22B of the base body 20 and a portion of the first negative direction X2 side of the four side surfaces 22C. In this embodiment, the material of the second base electrode 62A is the same as the material of the first external electrode 61, and is a mixture of silver and glass.

[0025] The second metal layer 62B covers the second base electrode 62A from the outside. Therefore, the second metal layer 62B is laminated on the second base electrode 62A. Specifically, the second metal layer 62B has a two-layer structure consisting of nickel plating and tin plating, similar to the first metal layer 61B.

[0026] The second external electrode 62 does not extend to the first external electrode 61 on the side surface 22C, and is positioned separately from the first external electrode 61 in the direction along the first axis X. Furthermore, on the side surface 22C of the base body 20, the central portion in the direction along the first axis X is not laminated with the first external electrode 61 and the second external electrode 62, and the glass film 50 is exposed. In Figures 1 to 3, the first external electrode 61 and the second external electrode 62 are shown by dashed lines.

[0027] As shown in Figure 3, the first external electrode 61 and the first positive X1 side end of the first internal electrode 41 are connected via a first extension 71 that penetrates the glass film 50. As will be described in detail later, the first extension 71 is formed during the manufacturing process of the electronic component 10 by the palladium constituting the first internal electrode 41 extending toward the first external electrode 61.

[0028] Furthermore, the second external electrode 62 and the end of the second internal electrode 42 on the first negative direction X2 side are connected via a second extension 72 that penetrates the glass film 50. The second extension 72, like the first extension 71, is formed during the manufacturing process of the electronic component 10 by the palladium constituting the second internal electrode 42 extending toward the second external electrode 62. In Figure 3, the first internal electrode 41 and the first extension 71 are shown as separate members with a boundary, but in reality, there is no clear boundary between the two. The same applies to the second extension 72. Also, the first extension 71 and the second extension 72 are not shown in Figures 1 and 2.

[0029] <About glass films> As shown in Figure 4, the glass film 50 has grooves 52 extending on its outer surface 51. When viewed in a direction perpendicular to the outer surface 51 of the glass film 50, the width of the opening edge 52B of the groove 52 on the outer surface 51 of the glass film 50 is defined as the opening width WG. In this case, if the extension length of the opening is 5 times or more than the opening width WG, it is referred to as "grooves 52 extending on the outer surface 51 of the glass film 50".

[0030] As shown in Figure 5, a specific cross-section is defined as a cross-section in a direction perpendicular to the outer surface 51 of the glass film 50. In this specific cross-section, the groove 52 is recessed from the outer surface 21 of the glass film 50 toward the outer surface 21 of the base material 20. The bottom 52A of the groove 52 is located on the outer surface 51 side of the glass film 50 rather than the outer surface 21 of the base material 20. In other words, the groove 52 does not penetrate the glass film 50.

[0031] The bottom 52A and opening edge 52B of the groove 52 are determined as follows. First, the surface of the glass film 50 is photographed with an electron microscope. Then, cross-sectional processing is performed at an arbitrary specific cross section that includes the observed groove 52. Elemental mapping is then performed on this specific cross section to obtain a mapping image that identifies the boundary between the glass film 50 and the substrate 20, and the surface opposite to the substrate 20. In this mapping image, the lowest point TB of the groove 52 that is closest to the outer surface 21 of the substrate 20 is identified. The area including the lowest point TB is the bottom 52A.

[0032] Furthermore, a mapping image of the glass film 50 is obtained in a specific cross-section as described above. Then, in the mapping image, a virtual line V is drawn that is tangent to either of the outer surfaces 51 of the glass film 50 on both sides of the groove 52. At this time, the virtual line V may partially coincide with the outer surface 51 of the glass film 50. The end of the point of contact between this virtual line V and the outer surface 51 of the glass film 50, on the side closer to the center of the groove 52, is defined as the opening edge 52B.

[0033] In a specific cross-section, the maximum depth SG of the groove 52 is approximately 750 nm. The maximum depth SG is the larger of the distances from both opening edges 52B to the lowest point TB in the direction perpendicular to the virtual line V described above. In this embodiment, the opening width WG is approximately 870 nm. The opening width WG is the distance from one opening edge 52B to the other opening edge 52B on the virtual line V.

[0034] In a specific cross-section, the bottom 52A of the groove 52 is arc-shaped. In other words, the bottom 52A is the region in a specific cross-section that includes the lowest point TB and is arc-shaped. Here, "arc" means that fine irregularities of less than 1 nm that cannot be clearly judged by observation with an electron microscope, for example, are ignored, and the region as a whole is arc-shaped. In a specific cross-section, the radius of curvature R1 of the bottom 52A of the groove 52 is 10 nm or more. In this embodiment, the radius of curvature R1 of the bottom 52A of the groove 52 is approximately 315 nm. As described above, the aperture width WG of the groove 52 is approximately 870 nm. Therefore, the radius of curvature R1 of the bottom 52A is one-quarter or more of the aperture width WG.

[0035] The radius of curvature R1 of the bottom portion 52A is defined as follows: First, a mapping image of the glass film 50 including the bottom portion 52A is obtained as described above. Then, an arc approximating the surface of the bottom portion 52A is identified in the mapping image. Next, an approximate circle 52C containing this arc is identified. The radius of this approximate circle 52C is taken as the radius of curvature R1.

[0036] In a specific cross-section, a portion of the inner wall 52D of the groove 52 is arc-shaped. Specifically, the specific tangent line SL is defined as a tangent line that is tangent to the inner wall 52D of the groove 52 and is inclined at 45 degrees with respect to the imaginary line V. The point of contact between the specific tangent line SL and the inner wall 52D of the groove 52 is defined as the specific contact SP. In this case, a portion PP of the inner wall 52D of the groove 52, including the specific contact SP, is arc-shaped. The radius of curvature R2 of this portion PP is 10 nm or more. In this embodiment, the radius of curvature R2 of the portion PP including the specific contact SP is approximately 40 nm to 60 nm. Note that in Figure 5, the illustration of the radius of curvature R2 of one portion PP is omitted.

[0037] <Regarding the thickness of the glass film> As shown in Figure 5, the shortest distance from the outer surface 21 of the base body 20 to the outer surface 51 of the glass film 50 is defined as the thickness TG of the glass film 50. The average value of the thickness TG of the glass film 50 in areas where grooves 52 are absent is 300 nm or more. Specifically, in this embodiment, the average value of the thickness TG of the glass film 50 is approximately 850 nm. The average value of the thickness TG of the glass film 50 in areas where grooves 52 are absent is calculated as follows.

[0038] First, a location on the outer surface 51 of the glass film 50 where no grooves 52 exist is identified. Next, a specific cross-section of the glass film 50 at that location is photographed with an electron microscope. For this image, a measurement range of at least 5 μm in the direction along the outer surface 51 of the glass film 50 is defined. Then, the cross-sectional area of ​​the glass film 50 in the measurement range is calculated by image processing. Finally, the average value of the thickness TG of the glass film 50 is calculated by dividing the cross-sectional area of ​​the glass film 50 in the measurement range by the length of the measurement range in the direction along the outer surface 51 of the glass film 50. In other words, the average value of the thickness TG of the glass film 50 is the average value of the thickness TG in the measurement range.

[0039] Furthermore, in a specific cross-section, the shortest distance SD from the bottom 52A of the groove 52 to the outer surface 21 of the base material 20 is approximately 90 nm. That is, in a specific cross-section, the ratio of the shortest distance SD from the bottom 52A of the groove 52 to the outer surface 21 of the base material 20 to the average value of the thickness TG of the glass film 50 is 10% or more. In this embodiment, this ratio is approximately 10.6%.

[0040] <Manufacturing methods for electronic components> Next, we will describe the manufacturing method of the electronic component 10. As shown in Figure 6, the manufacturing method for the electronic component 10 includes a laminate preparation step S11, an R-chamfering step S12, a solvent addition step S13, a catalyst addition step S14, a substrate addition step S15, a polymer addition step S16, and a metal alkoxide addition step S17. Furthermore, the manufacturing method for the electronic component 10 includes a film formation step S18, a drying step S19, an immersion step S20, a baking step S21, a conductive coating step S22, a curing step S23, and a plating step S24.

[0041] First, in forming the base body 20, the laminate preparation step S11 prepares a laminate which is a rectangular parallelepiped base body 20. That is, the laminate at this stage is in a state before R chamfering. For example, first, several ceramic sheets that will become the base body 20 are prepared. These sheets are thin plates. A conductive paste that will become the first internal electrode 41 is laminated onto these sheets. A ceramic sheet that will become the base body 20 is laminated onto the laminated paste. A conductive paste that will become the second internal electrode 42 is laminated onto these sheets. In this way, the ceramic sheets and conductive paste are laminated. Then, by cutting to a predetermined size, an unfired laminate is formed. After that, the unfired laminate is fired at a high temperature to prepare the laminate.

[0042] Next, as shown in Figure 6, the R-chamfering process S12 is performed. In the R-chamfering process S12, curved surfaces are formed at the boundaries between two adjacent planes and at the boundaries between three adjacent planes of the laminate prepared in the laminate preparation process S11. For example, the corners of the laminate are R-chamfered by barrel polishing, thereby forming the curved surfaces at the aforementioned boundaries.

[0043] Next, as shown in Figure 6, the solvent addition step S13 is performed. As shown in Figure 7, in the solvent addition step S13, 2-propanol is added to the reaction vessel 81 as the solvent 82. Next, as shown in Figure 6, the catalyst addition step S14 is performed. As shown in Figure 8, in the catalyst addition step S14, stirring of the solvent 82 in the reaction vessel 81 is started first. Then, aqueous ammonia water is added to the reaction vessel 81 as an aqueous solution 83 containing the catalyst. The catalyst in this embodiment is hydroxide ions and functions as a catalyst that promotes the hydrolysis of the metal alkoxide 85, which will be described later.

[0044] Next, as shown in Figure 6, the raw material input step S15 is performed. As shown in Figure 9, in the raw material input step S15, a plurality of raw materials 20 that were previously formed in the R-chamfering step S12 as described above are added to the reaction vessel 81.

[0045] Next, as shown in Figure 6, the polymer addition step S16 is performed. As shown in Figure 10, in the polymer addition step S16, polyvinylpyrrolidone is added to the reaction vessel 81 as polymer 84. As a result, the polymer 84 added to the reaction vessel 81 is adsorbed onto the outer surface 21 of the substrate 20.

[0046] Next, as shown in Figure 6, the metal alkoxide addition step S17 is performed. As shown in Figure 11, in the metal alkoxide addition step S17, liquid tetraethyl orthosilicate is added to the reaction vessel 81 as the metal alkoxide 85. Tetraethyl orthosilicate is sometimes referred to as tetraethoxysilane. In this embodiment, the amount of metal alkoxide 85 added in the metal alkoxide addition step S17 is calculated based on the area of ​​the outer surface 21 of the element 20 added in the element addition step S15. Specifically, it is calculated by multiplying the amount of metal alkoxide 85 per element 20 required to form a glass film 50 covering the outer surface 21 of the element 20 by the number of elements 20.

[0047] Next, as shown in Figure 6, the film formation process S18 is performed. In the film formation process S18, the stirring of the solvent 82, which was started in the solvent addition process S13 described above, is continued for a predetermined time after the metal alkoxide 85 is added to the reaction vessel 81 in the metal alkoxide addition process S17. As a result, the metal alkoxide 85 is hydrolyzed by hydroxide ions, which act as a catalyst. When the metal alkoxide 85 is hydrolyzed, the hydrolyzed metal alkoxide 85 adheres to the surface of the substrate 20. Then, the metal alkoxide 85 attached to the surface of the substrate 20 undergo dehydration condensation to form a glass film 50. In the film formation process S18, a sol-like glass film 50 is formed by a liquid-phase reaction in the reaction vessel 81.

[0048] Next, as shown in Figure 6, a drying step S19 is performed. In the drying step S19, after the film formation step S18, the substrate 20 is removed from the reaction vessel 81 and dried. As a result, the sol-like glass film 50 is dried and becomes a gel-like glass film 50. During the drying step S19, cracks occur that penetrate the glass film 50. These cracks are a preliminary stage to the formation of the grooves 52 described later. The occurrence of these cracks distributes the stress in the glass film 50.

[0049] Next, as shown in Figure 6, the immersion step S20 is performed. As shown in Figure 12, in the immersion step S20, first, a solution 87 containing at least one element selected from alkali metals and alkaline earth metals as an additive is placed in a reaction vessel 86, which is different from the reaction vessel 81 used up to the film formation step S18. In this embodiment, the solution 87 is a solution containing a potassium oxide precursor. Then, the substrate 20 having a gel-like glass film 50 is immersed in the solution 87. As a result, the solution 87 adheres to the surface of the glass film 50. Then, the melting point temperature of the glass film 50 decreases.

[0050] Next, as shown in Figure 6, the baking process S21 is performed. In the baking process S21, first, the substrate 20 that was immersed in the solution 87 in the immersion process S20 is removed from the reaction vessel 86. Then, the removed substrate 20 is fired in an atmosphere of 800 degrees for 20 minutes. As a result, the glass film 50 dissolves. A portion of the dissolved glass film 50 then penetrates into the cracks created in the drying process S19. As a result, the bottom portion 52A of the glass film 50 is formed on the outer surface 21 of the substrate 20 that is exposed inside the cracks in the glass film 50, and a groove 52 is formed. At this time, due to surface tension, the glass wets up at the point where it is in contact with the wall of the crack. Therefore, the bottom portion 52A becomes arc-shaped in a specific cross-section. Also, in the baking process S21, the solvent of the solution 87 adhering to the surface of the glass film 50 volatilizes. On the other hand, the potassium oxide precursor contained in the solution 87 precipitates on the outer surface 51 of the glass film 50.

[0051] Next, the conductive coating process S22 is performed. In the conductive coating process S22, conductive paste is applied to two locations on the surface of the glass film 50: one portion including the part covering the first end face 22A of the base body 20, and another portion including the part covering the second end face 22B of the base body 20. Specifically, conductive paste is applied to a portion of the base body 20 on the first positive direction X1 side, including the entire area of ​​the first end face 22A, so as to cover the glass film 50. In addition, conductive paste is applied to a portion of the base body 20 on the first negative direction X2 side, including the entire area of ​​the second end face 22B, so as to cover the glass film 50.

[0052] Next, the curing process S23 is performed. Specifically, the curing process S23 involves heating the substrate 20 to which the glass film 50 and conductive paste have been applied. This causes the precipitated potassium oxide precursor to become potassium oxide. The potassium oxide diffuses into the interior of the glass film 50 covering the outer surface 21 of the substrate 20. Then, water and polymer 84 vaporize from the gel-like glass film 50, causing the sol covering a portion of the outer surface 21 of the substrate 20 to harden. Furthermore, the conductive paste applied to the outer surface 21 of the substrate 20 hardens. In other words, the first base electrode 61A and the second base electrode 62A are fired.

[0053] In this embodiment, during heating in the curing process S23, the Kirkendall effect, resulting from the difference in diffusion rates between the first internal electrode 41 and the first base electrode 61A, attracts the palladium contained in the first internal electrode 41 to the silver-containing first base electrode 61A. As a result, the first extension 71 extends from the first internal electrode 41 toward the first base electrode 61A, penetrating the glass film 50, thereby connecting the first internal electrode 41 and the first base electrode 61A. The same applies to the second extension 72 connecting the second internal electrode 42 and the second base electrode 62A.

[0054] Next, the plating process S24 is performed. Electroplating is carried out on the first base electrode 61A and the second base electrode 62A. As a result, a first metal layer 61B is formed on the surface of the first base electrode 61A. Also, a second metal layer 62B is formed on the surface of the second base electrode 62A. Although not shown in the diagram, the first metal layer 61B and the second metal layer 62B are electroplated with two types of metal, nickel and tin, to form a two-layer structure. In this way, the electronic component 10 is formed.

[0055] <About barrier properties testing> A barrier property test was conducted on a substrate 20 covered with a glass film 50 having grooves 52. In this test, multiple samples were prepared for each of the five groups. That is, multiple samples each of Sample 1, Sample 2, Sample 3, Sample 4, and Sample 5 were prepared. The glass film 50 was formed by performing the substrate immersion process S15 to the baking process S21 described above. Furthermore, the thickness TG of the glass film 50 was made different for each group of samples by changing the conditions of each process for each of Samples 1 to 5. Then, each sample was left for 500 hours under conditions of a temperature of 85 degrees Celsius and a relative humidity of 90-95%. After that, the resistance value of each sample was measured. Samples that showed deterioration in resistance value were deemed defective. In this test, a decrease of 0.1% or more in resistance value compared to the resistance value before exposure to the above temperature and relative humidity conditions was judged as "deterioration of resistance value." This determination of whether or not a sample is defective was performed on multiple samples for each group of samples, and the rate of defective products for each group was calculated.

[0056] In Sample 1, the average thickness TG of the glass film 50 was 300 nm. The average radius of curvature R1 of the bottom 52A of the groove 52 in Sample 1 was 540 nm. The average radius of curvature R2 of a portion of the PP in the groove 52 in Sample 1 was 130 nm. The defect rate in Sample 1 was 0%.

[0057] In Sample 2, the average thickness TG of the glass film 50 was 850 nm. The average radius of curvature R1 of the bottom 52A of the groove 52 in Sample 2 was 310 nm. The average radius of curvature R2 of a portion of the PP in the groove 52 in Sample 2 was 10 nm. The defect rate in Sample 2 was 0%.

[0058] In Sample 3, the average thickness TG of the glass film 50 was 300 nm. The average radius of curvature R1 of the bottom 52A of the groove 52 in Sample 3 was 10 nm. The average radius of curvature R2 of a portion of the PP in the groove 52 in Sample 3 was 40 nm. The defect rate in Sample 3 was 0%.

[0059] In Sample 4, the average thickness TG of the glass film 50 was 100 nm. The average radius of curvature R1 of the bottom 52A of the groove 52 in Sample 4 was 30 nm. The average radius of curvature R2 of a portion of the PP in the groove 52 in Sample 4 was 50 nm. The defect rate in Sample 4 was 0.3%.

[0060] In sample 5, the average thickness TG of the glass film 50 was 300 nm. The average radius of curvature R1 of the bottom 52A of the groove 52 in sample 5 was 3 nm. The average radius of curvature R2 of a portion of the PP in the groove 52 in sample 5 was 8 nm. The defect rate in sample 5 was 0.2%.

[0061] In the case of sample 4, which had a defect, the average thickness TG of the glass film 50 was smaller compared to the other samples. In this case, it was found that the barrier properties were degraded compared to samples 1-3. Also, in the case of sample 5, which had a defect, the average radius of curvature R1 of the bottom 52A of the groove 52 was smaller compared to the other samples. In this case as well, it was found that the barrier properties were degraded compared to samples 1-3. Furthermore, in sample 5, the average radius of curvature R2 of a portion of the PP in the groove 52 was smaller compared to the other samples. In this case as well, it was found that the barrier properties were degraded compared to samples 1-3.

[0062] From the above tests, it can be said that the average value of the thickness TG of the glass film 50 is preferably 300 nm or more, and the radius of curvature R1 of the bottom 52A of the groove 52 is preferably 10 nm or more. Furthermore, if the radius of curvature R2 of a portion of the PP in the groove 52 is large, other objects are less likely to get caught near the opening edge 52B of the groove 52. In order to suppress such snagging and ensure the characteristics of the product, it can be said that the radius of curvature R2 of a portion of the PP in the groove 52 is preferably 10 nm or more.

[0063] <Effects of this embodiment> (1) According to the above embodiment, the presence of grooves 52 in the base body 20 releases stress in the glass film 50 in the grooves 52. Therefore, it is possible to prevent stress from concentrating at specific locations in the glass film 50. Furthermore, the grooves 52 do not penetrate the glass film 50. In other words, the outer surface 21 of the base body 20 is not exposed inside the grooves 52. Therefore, according to the above configuration, the barrier properties of the glass film 50 are ensured. In addition, the bottom portion 52A of the grooves 52 is arc-shaped. Therefore, it is possible to prevent the grooves 52 from extending toward the outer surface 21 of the base body 20. That is, it is possible to prevent the grooves 52 from unintentionally reaching the base body 20 and impairing the barrier properties of the glass film 50 by the grooves 52.

[0064] (2) In the above embodiment, the radius of curvature R1 of the bottom 52A of the groove 52 is 10 nm or more in a specific cross section. With this arc size, the curvature of the bottom 52A of the groove 52 is ensured to a certain extent. Therefore, the effects described in (1) can be fully obtained.

[0065] (3) In the above embodiment, in a specific cross section, the radius of curvature R1 of the bottom 52A of the groove 52 is one-quarter or more of the opening width WG of the opening edge 52B of the groove 52. In other words, the arc shape of the bottom 52A in the above embodiment is a sufficiently gentle arc, similar to the arc shape of the bottom 52A when the groove 52 is assumed to be semicircular. If the arc of the bottom 52A is gentle in this way, even if an external force is applied to the glass film 50, for example, the groove 52 can be effectively prevented from propagating from the bottom 52A.

[0066] (4) In the above embodiment, a portion of the inner wall 52D of the groove 52, including the specific contact SP, is arc-shaped. The radius of curvature R2 of this portion of PP is 10 nm or more. Here, the specific contact SP of the inner wall 52D is the part where the inclination of the groove 52 becomes steeper than 45 degrees. Therefore, the area corresponding to the specific contact SP is a place where other objects are likely to get caught when they rub against the electronic component 10. In this regard, as described above, since the portion of PP including the specific contact SP is rounded, other objects are less likely to get caught at the area of ​​the groove 52 corresponding to the specific contact SP. By suppressing such snagging, the scratch resistance of the glass film 50 is improved.

[0067] (5) In the above embodiment, the average value of the thickness TG of the glass film 50 in areas where the groove 52 is absent is 300 nm or more. With this configuration, sufficient barrier properties of the glass film 50 are ensured.

[0068] (6) In the above embodiment, in a specific cross-sectional view, the ratio of the shortest distance SD from the bottom 52A of the groove 52 to the outer surface 21 of the base body 20 to the average value of the thickness TG of the glass film 50 is 10% or more. With this configuration, even in the area where the glass film 50 is thinnest, a corresponding thickness of the glass film 50 is ensured. That is, the barrier properties of the glass film 50 are ensured.

[0069] <Example of changes> The above embodiments and the following modifications can be combined and implemented to the extent that they do not contradict each other technically.

[0070] • The electronic component 10 is not limited to a negative-characteristic thermistor component. For example, it may also be a multilayer capacitor component or an inductor component. The material of the base body 20 is not limited to the examples of the above embodiment. The material of the base body 20 may be a composite of resin and metal powder.

[0071] The shape of the base body 20 is not limited to the examples of the above embodiments. For example, the base body 20 may be a polygonal columnar shape other than a rectangular columnar shape having a central axis CA. The base body 20 may also be the core of a wound-type inductor component. For example, the core may be a so-called drum core shape. Specifically, the core may have a columnar winding core portion and flange portions provided at each end of the winding core portion.

[0072] The boundary portions of adjacent planes on the outer surface 21 of the base body 20 do not necessarily have to be chamfered. In this case, there are no curved surfaces at the boundary portions. The shapes of the first internal electrode 41 and the second internal electrode 42 are not limited as long as they can ensure electrical conductivity with the corresponding first external electrode 61 and the second external electrode 62. Also, there is no limit to the number of first internal electrodes 41 and second internal electrodes 42; there may be one internal electrode or three or more.

[0073] The configuration of the first external electrode 61 is not limited to the examples of the above embodiment. For example, the first external electrode 61 may consist only of the first base electrode 61A, and the first metal layer 61B may not have a two-layer structure. The same applies to the second external electrode 62.

[0074] The combination of materials between the first internal electrode 41 and the first base electrode 61A is not limited to a combination of palladium and silver. For example, it may be a combination of copper and nickel, copper and silver, silver and gold, nickel and cobalt, or nickel and gold. Alternatively, one may be silver and the other a combination of silver and palladium. Alternatively, one may be palladium and the other a combination of silver and palladium, or one may be copper and the other a combination of silver and palladium. Alternatively, one may be gold and the other a combination of silver and palladium.

[0075] • In some cases, the Kirkendall effect may not be obtained depending on the combination of the first internal electrode 41 and the first base electrode 61A. In this case, the first internal electrode 41 may be processed so that it is exposed from the glass film 50 before the conductive coating process S22. For example, the glass film 50 on the first end face 22A side of the base body 20 may be polished to physically remove a portion of the glass film 50. After that, the first internal electrode 41 and the first base electrode 61A can be connected by performing the conductive coating process S22. Alternatively, for example, after forming the first base electrode 61A, the glass film 50 may be formed including on the surface of the first base electrode 61A, and then the glass film 50 covering the surface of the first base electrode 61A may be removed. The same applies to the material combination of the second internal electrode 42 and the second base electrode 62A.

[0076] The placement of the first external electrode 61 is not limited to the example of the embodiment described above. For example, the first external electrode 61 may be placed only on the first end face 22A and one side face 22C. The same applies to the second external electrode 62.

[0077] In the specific cross-section of the above embodiment, the radius of curvature R1 of the bottom 52A of the groove 52 may be less than 10 nm. As long as the bottom 52A is at least arc-shaped, the effects described in (1) can be expected.

[0078] In the specific cross-section of the above embodiment, the radius of curvature R2 of a portion PP of the inner wall 52D of the groove 52, including the specific contact SP, may be less than 10 nm. Furthermore, the portion PP does not have to be arc-shaped.

[0079] In the above embodiment, a portion of the glass film 50, including the opening edge 52B, may be arc-shaped. In the example shown in Figure 13, the glass film 50 has a groove 52 extending on the outer surface 51 of the glass film 50. The cross section in a direction perpendicular to the outer surface 51 of the glass film 50 is called a specific cross section. In the specific cross section, the groove 52 is recessed from the outer surface 21 of the glass film 50 toward the outer surface 21 of the base material 20. The bottom 52A of the groove 52 is located on the outer surface 51 side of the glass film 50 than the outer surface 21 of the base material 20. That is, the groove 52 does not penetrate the glass film 50. In the specific cross section, the bottom 52A of the groove 52 is arc-shaped. In the example shown in Figure 13, the radius of curvature R1 of the bottom 52A of the groove 52 is approximately 1 μm.

[0080] In the example shown in Figure 13, in a specific cross-section, a portion PQ including the opening edge 52B of the groove 52 is arc-shaped. Specifically, this portion PQ is a convex arc toward the opposite side from the base body 20. The radius of curvature of this portion PQ is 10 nm or more. In the example shown in Figure 13, the radius of curvature of the arc of portion PQ is approximately 10 to 30 nm.

[0081] Furthermore, in the example shown in Figure 13, the opening width WG of the opening edge 52B of the groove 52 is approximately 1.2 μm in a specific cross-section. That is, in a specific cross-section, the radius of curvature R1 of the bottom 52A of the groove 52 is one-quarter or more of the opening width WG of the opening edge 52B of the groove 52.

[0082] Furthermore, as shown in the example in Figure 13, suppose a first imaginary line V1 is drawn connecting the opening edges 52B on both sides of the groove 52 in a specific cross-section. Then, suppose an intermediate position MP is defined as the position where the maximum depth SG of the groove 52 is halved, and a second imaginary line V2 is drawn passing through the intermediate position MP and parallel to the first imaginary line V1. In a specific cross-section, it is preferable that twice the radius of curvature R1 of the bottom 52A of the groove 52 is greater than or equal to the length at which the second imaginary line V2 is demarcated by the inner wall 52D of the groove 52 in that specific cross-section. With such a configuration, the arc of the bottom 52A of the groove 52 is larger than the scale of the opening width WG of the groove 52. Therefore, stress is sufficiently distributed at the bottom 52A of the glass film 50 in the bottom 52A of the groove 52. Although not shown in the figures, in the above embodiment as well, twice the radius of curvature R1 of the bottom 52A of the groove 52 is greater than or equal to the length at which the second imaginary line V2 is demarcated by the inner wall 52D of the groove 52 in a specific cross-section.

[0083] In the above embodiment, the average thickness TG of the glass film 50 in areas where the groove 52 is absent may be less than 300 nm. Also, in a specific cross-section, the ratio of the shortest distance SD from the bottom 52A of the groove 52 to the outer surface 21 of the base body 20 to the average thickness TG of the glass film 50 may be less than 10%. That is, the bottom 52A of the groove 52 only needs to be located on the outer surface 51 side of the glass film 50 than the outer surface 21 of the base body 20.

[0084] The configuration of the glass film 50 is not limited to the examples of the above embodiment. For example, it does not have to cover all areas of the outer surface 21 of the base body 20. The area covered by the glass film 50 may be appropriately changed in accordance with the shape of the base body 20, the positions of the first external electrode 61 and the second external electrode 62, etc.

[0085] The glass contained in the glass film 50 may diffuse into the first substrate electrode 61A, causing the glass film 50 and the first substrate electrode 61A to become integrated. The same applies to the glass film 50 and the second substrate electrode 62A.

[0086] The glass film 50 does not need to contain one or more elements selected from alkali metals and alkaline earth metals as additives. The material of the glass film 50 is not limited to the examples of the above embodiments. For example, the glass is not limited to silicon dioxide, but may be a multi-component oxide containing Si, such as B-Si, Si-Zn, Zr-Si, or Al-Si oxides. The glass may also be a multi-component oxide containing alkali metals and Si, such as Al-Si, Na-Si, or Li-Si oxides. Furthermore, the glass may be a multi-component oxide containing alkaline earth metals and Si, such as Mg-Si, Ca-Si, Ba-Si, or Sr-Si oxides. And the glass does not have to contain Si; it may be a mixture of these.

[0087] The material of the glass film 50 may include, in addition to glass, a pigment, a silicone-based flame retardant, a silane coupling agent, a titanate coupling agent, or other surface treatment agents or antistatic agents.

[0088] More specifically, the glass film 50 may contain, in addition to glass, additives such as organic acid salts, oxides, inorganic salts, organic salts, and other fine particles and nanoparticles of metal oxides. Furthermore, the additives contained in solution 87 are not limited to potassium oxide precursors.

[0089] Examples of organic acid salts include salts of oxoacids such as soda ash, sodium carbonate, sodium bicarbonate, sodium percarbonate, sodium sulfite, sodium bisulfite, sodium sulfate, sodium thiosulfate, sodium nitrate, and sodium sulfite, as well as halogen compounds such as sodium fluoride, sodium chloride, sodium bromide, and sodium iodide.

[0090] Examples of oxides include sodium peroxide, and examples of hydroxides include sodium hydroxide. Examples of inorganic salts include sodium hydride, sodium sulfide, sodium hydrogen sulfide, sodium silicate, trisodium phosphate, sodium borate, sodium borohydride, sodium cyanide, sodium cyanate, and sodium tetrachloroaurate.

[0091] In addition, examples of inorganic salts include calcium peroxide, calcium hydroxide, calcium fluoride, calcium chloride, calcium bromide, calcium iodide, calcium hydride, calcium carbide, and calcium phosphide.

[0092] Additives may include oxo salts such as calcium carbonate, calcium bicarbonate, calcium nitrate, calcium sulfate, calcium sulfite, calcium silicate, calcium phosphate, calcium pyrophosphate, calcium hypochlorite, calcium chlorate, calcium perchlorate, calcium bromate, calcium iodate, calcium arsenite, calcium chromate, calcium tungstate, calcium molybdate, calcium magnesium carbonate, and hydroxyapatite. Other additives include calcium acetate, calcium gluconate, calcium citrate, calcium malate, calcium lactate, calcium benzoate, calcium stearate, and calcium aspartate.

[0093] For example, the additives may also be lithium carbonate, lithium chloride, lithium titanate, lithium nitride, lithium peroxide, lithium citrate, lithium fluoride, lithium hexafluorophosphate, lithium acetate, lithium iodide, lithium hypochlorite, lithium tetraborate, lithium bromide, lithium nitrate, lithium hydroxide, lithium aluminum hydride, lithium triethylborohydride, lithium hydride, lithium amide, lithium imide, lithium diisopropylamide, lithium tetramethylpiperizide, lithium sulfide, lithium sulfate, lithium thiophenolate, or lithium phenoxide.

[0094] For example, the additives may also be boron triiodide, sodium cyanoborohydride, sodium borohydride, tetrafluoroboric acid, triethylborane, borax, or boric acid.

[0095] For example, the additives may also be barium sulfite, barium chloride, barium chlorate, barium perchlorate, barium peroxide, barium chromate, barium acetate, barium cyanide, barium bromide, barium oxalate, barium nitrate, barium hydroxide, barium hydride, barium carbonate, barium iodide, barium sulfide, and barium sulfate. Other additives may also be sodium acetate and sodium citrate.

[0096] Furthermore, the additives may be fine particles or nanoparticles of metal oxides. Examples of metal oxides include sodium oxide, calcium oxide, lithium oxide, boron oxide, barium oxide, silicon oxide, titanium oxide, zircon oxide, aluminum oxide, zinc oxide, and magnesium oxide.

[0097] Furthermore, in the above embodiments, the potassium oxide precursor is, for example, potassium arsenide, potassium bromide, potassium carbide, potassium chloride, potassium fluoride, potassium hydride, potassium iodide, potassium triiodide, potassium azide, potassium nitride, potassium superoxide, potassium ozonide, potassium peroxide, potassium phosphide, potassium sulfide, potassium selenide, potassium telluride, potassium tetrafluoroaluminate, potassium tetrafluoroborate, potassium tetrahydroborate, potassium methanide, potassium cyanide, potassium formate, and potassium hydrogen fluoride. Potassium, tetrachloride, potassium mercury(II), potassium hydrogen sulfide, potassium octachlorodimolybdenate(II), potassium amide, potassium hydroxide, potassium hexafluorophosphate, potassium carbonate, potassium tetrachloride platinum(II), potassium hexachloride platinum(IV), potassium nonahydridorhenium(VII), potassium sulfate, potassium acetate, potassium gold(I) cyanide, potassium hexanitrocobalt(III), potassium hexacyanoferrate(III), potassium hexacyanoferrate(II), potassium methotrexate Potassium oxide, potassium ethoxide, potassium tert-butoxide, potassium cyanate, potassium fulminate, potassium thiocyanate, potassium aluminum sulfate, potassium aluminate, potassium arsenate, potassium bromate, potassium hypochlorite, potassium chlorite, potassium chlorate, potassium perchlorate, potassium carbonate, potassium chromate, potassium dichromate, potassium tetrakis(peroxo)chromate(V), potassium copper(III)ate, potassium ironate, potassium iodate, potassium periodate, potassium permanganate, potassium manganese, Examples include potassium hypomanganite, potassium molybdate, potassium nitrite, potassium nitrate, tripotassium phosphate, potassium perrhenate, potassium selenate, potassium silicate, potassium sulfite, potassium sulfate, potassium thiosulfate, potassium disulfite, potassium dithionate, potassium disulfate, potassium peroxodisulfate, potassium dihydrogen arsenate, dipotassium hydrogen arsenate, potassium bicarbonate, potassium dihydrogen phosphate, dipotassium hydrogen phosphate, potassium hydrogen selenate, potassium bisulfite, potassium bisulfate, and potassium peroxobisulfate.

[0098] Metal alkoxides 85 include, for example, sodium methoxide, sodium ethoxide, calcium diethoxide, lithium isopropoxide, lithium ethoxide, lithium tert-butoxide, lithium methoxide, boron alkoxide, potassium t-butoxide, tetraethyl orthosilicate, allyl trimethoxysilane, isobutyl(trimethoxy)silane, tetrapropyl orthosilicate, tetramethyl orthosilicate, [3-(diethylamino)propyl]trimethoxysilane, triethoxy( Octyl)silane, triethoxyvinylsilane, triethoxyphenylsilane, trimethoxyphenylsilane, trimethoxymethylsilane, butyltrichlorosilane, n-propyltriethoxysilane, methyltrichlorosilane, dimethoxy(methyl)octylsilane, dimethoxydimethylsilane, tris(tert-butoxy)silanol, tris(tert-pentoxy)silanol, hexadecyltrimethoxysilane, tris(1,2-benzenediolate-O,O')dipotassium silicate, ol Tetrabutyl tosilicate, aluminum silicate, calcium silicate, tetramethylammonium silicate solution, chlorotriisopropoxytitanium(IV), titanium(IV) isopropoxide, titanium(IV) 2-ethylhexyl oxide, titanium(IV) ethoxide, titanium(IV) butoxide, titanium(IV) tert-butoxide, titanium(IV) propoxide, titanium(IV) methoxide, zirconium(IV) bis(diethyl citrate) dipropoxide, zirconium(IV) dibutoxide ( It may also be bis-2,4-pentanedione, zirconium(IV) 2-ethylhexanoate, zirconium(IV) isopropoxide isopropanol complex, zirconium(IV) ethoxide, zirconium(IV) butoxide, zirconium(IV) tert-butoxide, zirconium(IV) propoxide, aluminum tert-butoxide, aluminum isopropoxide, aluminum ethoxide, aluminum tri-sec-butoxide, or aluminum phenoxide.

[0099] In the above embodiment, the method for manufacturing the electronic component 10 may differ from that of the above embodiment. For example, the glass film 50 may be formed by the following method. First, a thin film that will be the basis for the glass film 50 is formed on the outer surface 21 of the beveled base body 20 by a barrel spray method or the like. Then, the glass film 50 is formed by adding an additive containing at least one element selected from alkali metals and alkaline earth metals to the thin film.

[0100] The solvent 82 added in the solvent addition step S13 is not limited to the example of the above embodiment, and any liquid that can adequately disperse the metal alkoxide 85 is acceptable. The solvent addition step S13 may be performed after the catalyst addition step S14 or the element addition step S15. The solvent addition step S13 may be performed before at least one of the metal alkoxide addition step S17 and the catalyst addition step S14. The solvent addition step S13 may also be omitted. In this case, for example, if the amount of water in the aqueous solution 83 containing the catalyst is sufficiently large, the metal alkoxide 85 will react in the liquid phase. Alternatively, the aqueous solution 83 containing the catalyst may be added in a state mixed with the organic solvent 82.

[0101] The aqueous solution 83 containing the catalyst is aqueous ammonia, and the catalyst is a hydroxide ion, but the catalyst is not limited to this. Any basic aqueous solution can catalyze the hydrolysis of the metal alkoxide 85, similar to the aqueous ammonia in the above embodiment, and even an acidic aqueous solution can catalyze the hydrolysis of the metal alkoxide 85. Furthermore, even a neutral aqueous solution is acceptable as long as it contains ions that can catalyze hydrolysis.

[0102] Although it has been explained that the catalyst is introduced as an aqueous solution 83 containing the catalyst, the solid compound containing the catalyst and water may be introduced into the reaction vessel 81 separately. In this case, the catalyst can be considered introduced into the reaction vessel 81 because it has been formed inside the reaction vessel 81. Alternatively, for example, the solid compound containing the catalyst may be introduced into the reaction vessel 81, and moisture from the air may be used as the water necessary for hydrolysis.

[0103] The substrate addition step S15 may be performed before the catalyst addition step S14. Also, if the substrate addition step S15 is performed before the catalyst addition step S14, the metal alkoxide addition step S17 may be performed before the catalyst addition step S14 or the substrate addition step S15. The substrate addition step S15 only needs to be performed before at least one of the metal alkoxide addition step S17 and the catalyst addition step S14.

[0104] In the method for manufacturing the electronic component 10 of the above embodiment, instead of the metal alkoxide 85, a solution containing a precursor for generating the metal alkoxide 85 may be added. In this case, in the metal alkoxide addition step S17, a metal complex or acetate, which is a metal alkoxide precursor, may be added. Examples of metal complexes include acetylacetonates such as lithium acetylacetonate, titanium(IV) oxyacetylacetonate, titanium diisopropoxide bis(acetylacetonate), zirconium(IV) trifluoroacetylacetonate, zirconium(IV) acetylacetonate, aluminum acetylacetate, aluminum(III) acetylacetonate, calcium(II) acetylacetonate, and zinc(II) acetylacetonate. Examples of acetates include zirconium acetate, zirconium(IV) hydroxide acetate, and basic aluminum acetate.

[0105] The metal alkoxide addition step S17 does not require the metal alkoxide 85 to be generated outside the reaction vessel 81 and then added to the reaction vessel 81; instead, the metal alkoxide 85 may be generated inside the reaction vessel 81. For example, metal alkoxide 85 is produced by the reaction of a metal salt and an alcohol. Therefore, if a metal salt, which is a metal alkoxide precursor, and an alcohol are added to the reaction vessel 81, and these react to produce metal alkoxide 85, this can be considered as the metal alkoxide 85 being added to the reaction vessel 81.

[0106] • Metal alkoxide 85 is not limited to tetraethyl orthosilicate. For example, the metal contained in metal alkoxide 85 may be titanium, zirconium, aluminum, etc. When the metal contained in metal alkoxide 85 is silicon, the reaction rate is slower compared to other metals, making it easier to control the reaction rate of metal alkoxide 85 to a constant level. Furthermore, the alkoxy group of metal alkoxide 85 may be a methoxy group, a propoxy group, etc., or it may be modified with functional groups such as long-chain alkyl groups or epoxy groups, as in a coupling agent. In addition, the coordination number with respect to the metal contained in metal alkoxide 85 is not limited to 4-coordination, but may be 3-coordination or 2-coordination.

[0107] The reaction vessel 81 used in the immersion process S20 and the reaction vessel 86 used in the film formation process S18 do not need to be different. In the immersion step S20, it is sufficient for the solution 87 to adhere to the glass film 50 covering the outer surface 21 of the substrate 20; it is not necessary to immerse the entire substrate 20 in the solution 87 in the reaction vessel 86. For example, the solution 87 may be applied only to the portion of the outer surface 21 of the substrate 20 that is covered by the glass film 50. Furthermore, the method of adding alkali metals and alkaline earth metals to the gel-like glass film 50 is not limited to immersion; they may also be added by spraying or other means.

[0108] The curing step S23 is not limited to a step in which the glass film 50 and the conductive paste are cured simultaneously. For example, if the conductive paste is a material that is cured by ultraviolet irradiation, a heating step may be performed as a step in curing the glass film 50, and ultraviolet irradiation may be performed as a step in curing the conductive paste.

[0109] In the above embodiment, after performing the substrate input step S15 to the drying step S19 once, the substrate input step S15 to the drying step S19 may be repeated again. By repeating these steps, the thickness TG of the glass film 50 increases.

[0110] In the above embodiment, after performing the immersion process S20 and the baking process S21 once, the immersion process S20 and the baking process S21 may be repeated. By repeatedly performing these processes, the shortest distance SD from the bottom 52A of the groove 52 to the outer surface 21 of the base body 20 increases, and the radius of curvature R1 of the bottom 52A changes.

[0111] <Note> The technical concepts that can be derived from the above embodiments and modifications are described below. [1] An electronic component comprising a body and a glass film covering the outer surface of the body, wherein the glass film extends on the outer surface of the glass film and has a groove in a specific cross section in a direction perpendicular to the outer surface of the glass film that is recessed from the outer surface of the glass film toward the outer surface of the body, the bottom of the groove is located on the outer surface side of the glass film than the outer surface of the body, and the bottom of the groove is arc-shaped in the specific cross section.

[0112] [2] The electronic component according to [1], wherein in the specific cross section, the radius of curvature of the bottom of the groove is 10 nm or more. [3] In the specific cross section, the radius of curvature of the bottom of the groove is one-quarter or more of the width of the opening edge of the groove, as described in [1] or [2].

[0113] [4] In the specific cross section, a line connecting the opening edges on both sides of the groove is defined as a virtual line, a tangent line touching the inner wall of the groove that is inclined at 45 degrees with respect to the virtual line is defined as the specific tangent, and the point of contact between the specific tangent and the inner wall of the groove is defined as the specific contact point, wherein in the specific cross section, a portion of the inner wall of the groove including the specific contact point is arc-shaped, and the radius of curvature of the portion is 10 nm or more, as described in any one of [1] to [3].

[0114] [5] The electronic component according to any one of [1] to [4], wherein the average thickness of the glass film in areas where the groove is absent is 300 nm or more. [6] In the specific cross section, the ratio of the shortest distance from the bottom of the groove to the outer surface of the body to the average value of the thickness of the glass film is 10% or more. The electronic component according to any one of [1] to [5]. [Explanation of Symbols]

[0115] 10…Electronic components 20... Base body 21...Outer surface 50…Glass film 51...Outer surface 52...Groove 52A…Bottom 52B...Opening edge

Claims

1. It comprises a base body and a glass film covering the outer surface of the base body, The glass film extends on the outer surface of the glass film and has a groove in a specific cross-section perpendicular to the outer surface of the glass film that is recessed from the outer surface of the glass film toward the outer surface of the base body. The bottom of the groove is located on the outer surface side of the glass film rather than the outer surface of the base body. In the aforementioned specific cross-section, the bottom of the groove is arc-shaped. Electronic components.

2. In the aforementioned specific cross-section, the radius of curvature at the bottom of the groove is 10 nm or more. The electronic component according to claim 1.

3. In the aforementioned specific cross-section, the radius of curvature of the bottom of the groove is one-quarter or more of the width of the opening edge of the groove. The electronic component according to claim 1.

4. In the aforementioned specific cross-section, the line connecting the opening edges on both sides of the groove is defined as a virtual line. A tangent line that is in contact with the inner wall of the groove and is inclined at a 45-degree angle with respect to the imaginary line is defined as the specific tangent line. When the contact point between the specified tangent and the inner wall of the groove is defined as the specified contact point, In the aforementioned specific cross-section, a portion of the inner wall of the groove, including the aforementioned specific contact point, is arc-shaped. The radius of curvature of the aforementioned portion is 10 nm or more. The electronic component according to claim 1.

5. The average thickness of the glass film in areas where the groove is absent is 300 nm or more. The electronic component according to claim 1.

6. In the aforementioned specific cross-section, the ratio of the shortest distance from the bottom of the groove to the outer surface of the substrate to the average value of the thickness of the glass film is 10% or more. The electronic component according to claim 1.

Images