Electronic module and method for manufacturing an electronic module

Abstract

The expected barrier properties may not be obtained relative to the average thickness of the barrier layer. [Solution] The electronic element 10 comprises a component body 11 and a protective film 16. The protective film 16 covers the outer surface of the component body 11 and comprises an organic film 16A mainly composed of organic components, and a first barrier film 16B mainly composed of inorganic components that covers the organic film 16A. The minimum thickness of the first barrier film 16B is 15 nm or more, and the maximum thickness of the first barrier film 16B is 65 nm or less.

Description

Technical Field

[0001] The present invention relates to an electronic module and a method for manufacturing an electronic module.

Background Art

[0002] The hybrid film of Patent Document 1 includes a plastic film, an anchor coat layer, a first barrier layer, and a second barrier layer. The anchor coat layer is a layer made of resin laminated on the plastic film. Each barrier layer is laminated on the anchor coat layer in the order of the first barrier layer, the second barrier layer, and the first barrier layer. Both the first barrier layer and the second barrier layer are layers made of SiOC.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the hybrid film as disclosed in Patent Document 1, the film thickness of each barrier layer affects the barrier property of the entire hybrid film. However, especially when the film thickness of the barrier layer is small, the expected barrier property may not be obtained with respect to the average film thickness of the barrier layer.

Means for Solving the Problems

[0005] The electronic module for solving the above problems includes a specific component, an organic film covering the outer surface of the specific component and mainly composed of an organic component, and a first barrier film directly covering the organic film and mainly composed of an inorganic component. The minimum value of the film thickness of the first barrier film is 15 nm or more, and the maximum value of the film thickness of the first barrier film is 65 nm or less.

[0006] A method for manufacturing an electronic module to solve the above problems comprises a first film formation step of forming an organic film mainly composed of organic components on the outer surface of a specific component, and a second film formation step of forming a first barrier film mainly composed of inorganic components on the outer surface of the organic film by atomic layer deposition, wherein in the second film formation step, the first barrier film is formed such that the minimum thickness of the first barrier film is 15 nm or more and the maximum thickness of the first barrier film is 65 nm or less. [Effects of the Invention]

[0007] This increases the likelihood of obtaining barrier properties that correspond to the average thickness of the first barrier layer. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a cross-sectional view of the electronic module according to the first embodiment. [Figure 2] Figure 2 is a partial cross-sectional view of the electronic module of the first embodiment. [Figure 3] Figure 3 is an enlarged cross-sectional view of the protective layer of the electronic module according to the first embodiment. [Figure 4] Figure 4 is a flowchart showing each step of the manufacturing method for the electronic module according to the first embodiment. [Figure 5] Figure 5 is a cross-sectional view of the electronic module according to the second embodiment. [Figure 6] Figure 6 is a partial cross-sectional view of the electronic module of the second embodiment. [Figure 7] Figure 7 is a cross-sectional view of the electronic module according to the third embodiment. [Figure 8] Figure 8 is a partial cross-sectional view of the electronic module of the third embodiment. [Figure 9] Figure 9 is a cross-sectional view of the electronic module according to the fourth embodiment. [Figure 10] Figure 10 is a partial cross-sectional view of the electronic module of the fourth embodiment. [Figure 11] Figure 11 is a partial cross-sectional view of the modified electronic module. [Modes for carrying out the invention]

[0009] The following describes various embodiments of the electronic module with reference to the drawings. Note that the drawings may show enlarged versions of components for easier understanding. The dimensional ratios of the components may differ from those in the actual components or those shown in other drawings. Furthermore, as illustrated in the following embodiments, an electronic module is a concept that includes passive elements that act electrically or magnetically when energized, active elements that operate when energized, and assemblies in which these elements are mounted on a wiring board.

[0010] <Configuration of the first embodiment> An embodiment of the electronic element 10 as an electronic module will be described. Examples of the electronic element 10 include inductors, capacitors, thermistors, and switches.

[0011] As shown in Figure 1, the electronic element 10 includes a component body 11 as a specific component. The component body 11 further includes a base body 12 and a pair of external terminals 13. The material of the base body 12 is an insulator. For example, the material of the base body 12 is a sintered ceramic body.

[0012] The shape of the base body 12 is generally that of a rectangular parallelepiped. Therefore, the base body 12 has six planes as its outer surface. In the following, one of the six planes of the base body 12 will be referred to as the first plane 12A. Of the six planes of the base body 12, the plane adjacent to the first plane 12A and extending in a direction perpendicular to the first plane 12A will be referred to as the second plane 12B. Therefore, there are four second planes 12B. Furthermore, of the six planes of the base body 12, the face opposite to the first plane 12A will be referred to as the third plane 12C. The portion of the outer surface of the base body 12 between each plane will be referred to as the edge portion 12D. In this embodiment, the edge portion 12D of the base body 12 is a curved portion that is convex toward the outside of the base body 12. That is, the edge portion 12D has a so-called R-chamfer shape.

[0013] The material of each external terminal 13 is a conductive metal. Therefore, each external terminal 13 is a metal member. Each external terminal 13 protrudes from the first plane 12A of the element body 12. Therefore, a part of the tip side of each external terminal 13 is exposed outside the element body 12. And the base end of each external terminal 13 is connected to an external electrode on the surface of the element body 12. Each external terminal 13 is connected to an internal wiring located inside the element body 12 via this external electrode. In FIG. 1, illustration of the external electrode on the surface of the element body 12 and the internal terminals inside the element body 12 is omitted. Each external terminal 13 is arranged at a position spaced apart from each other.

[0014] The electronic element 10 includes a sealing material 15. The material of the sealing material 15 is a thermosetting synthetic resin. Also, the sealing material 15 is insulating. Specifically, for example, as the material of the sealing material 15, a polyimide resin, an epoxy resin, an acrylic resin, etc. can be adopted.

[0015] The sealing material 15 covers the entire outer surface of the element body 12. Therefore, the sealing material 15 covers not only the first plane 12A, the second plane 12B, and the third plane 12C, but also the ridge line portion 12D. Also, the sealing material 15 covers a part of the outer surface of each external terminal 13. Specifically, as shown in FIG. 2, the sealing material 15 covers the vicinity of the boundary between the outer surface of each external terminal 13 and the first plane 12A of the element body 12. On the other hand, the sealing material 15 does not cover a part of the tip side of each external terminal 13. In the following, when simply expressed as "covering", it includes not only the case of covering directly in contact but also the case of not directly contacting with other members interposed therebetween.

[0016] As shown in FIG. 2, the electronic device 10 includes a protective film 16. Note that FIG. 2 is a cross-sectional view of the electronic device 10 in the vicinity of the base end of the external terminal 13. In FIG. 1, the shapes of the sealing material 15 and the protective film 16 in the vicinity of the base end of the external terminal 13 are shown in a simplified manner. As shown in FIG. 2, the protective film 16 includes an organic film 16A, a first barrier film 16B, and a second barrier film 16C. That is, the protective film 16 has a three-layer structure. These three films are laminated in the order of the organic film 16A, the first barrier film 16B, and the second barrier film 16C in this order from the side of the sealing material 15. In FIG. 1, the illustration of the three-layer structure of the protective film 16 is omitted and is shown as if it were a film consisting of one layer.

[0017] The material of the organic film 16A is mainly composed of an organic component. Here, the organic component is a component of a molecule having a carbon chain as a main skeleton. And the main component means that the ratio to the whole is more than 50% in terms of weight ratio. Therefore, the organic film 16A may partially have an inorganic component as an additive such as a stabilizer or a dispersant. As the material of the organic film 16A, for example, silicon-containing polyimide, parylene, or the like can be adopted. In this embodiment, the material of the organic film 16A is silicon-containing polyimide.

[0018] The organic film 16A covers the entire outer surface of the element body 12 from the outside of the sealing material 15. Therefore, the organic film 16A covers not only the first plane 12A, the second plane 12B, and the third plane 12C but also the ridge line portion 12D. The organic film 16A also covers a part of the outer surface of each external terminal 13. Specifically, the organic film 16A covers the boundary BL between the portion covered by the sealing material 15 and the portion not covered by the sealing material 15 on the outer surface of each external terminal 13. In other words, the edge of the organic film 16A is located outside the edge of the sealing material 15. On the other hand, the organic film 16A does not cover a part of the tip side of each external terminal 13.

[0019] The material of the first barrier film 16B mainly consists of inorganic components. Here, inorganic components are components that do not have carbon chains. Therefore, the first barrier film 16B may partially contain organic components as additives such as stabilizers and dispersants. Examples of materials for the first barrier film 16B include aluminum oxide, titanium oxide, and hafnium oxide. In this embodiment, the material of the first barrier film 16B is aluminum oxide.

[0020] The first barrier film 16B covers the entire outer surface of the base body 12 from the outside of the organic film 16A. Therefore, the first barrier film 16B covers not only the first plane 12A, the second plane 12B, and the third plane 12C, but also the ridge portion 12D. Furthermore, the first barrier film 16B directly covers the organic film 16A. In other words, the first barrier film 16B is in contact with the organic film 16A. In addition, the first barrier film 16B covers a portion of the outer surface of each external terminal 13. Specifically, the first barrier film 16B covers the boundary BL between the portion of the outer surface of each external terminal 13 that is covered by the sealing material 15 and the portion that is not covered by the sealing material 15. On the other hand, the first barrier film 16B does not cover a portion of the tip side of each external terminal 13. Furthermore, the edge of the first barrier film 16B coincides with the edge of the organic film 16A. In other words, the first barrier film 16B directly covers the entire outer surface S2 of the organic film 16A, while not protruding outward from the organic film 16A.

[0021] The material of the second barrier film 16C is different from the material of the first barrier film 16B. The material of the second barrier film 16C can be silicon-containing polyimide, parylene, etc. In this embodiment, the material of the second barrier film 16C is parylene.

[0022] The second barrier film 16C covers the entire outer surface of the base body 12 from the outside of the first barrier film 16B. Therefore, the second barrier film 16C covers not only the first plane 12A, the second plane 12B, and the third plane 12C, but also the ridge portion 12D. Furthermore, the second barrier film 16C covers a portion of the outer surface of each external terminal 13. Specifically, the second barrier film 16C covers the boundary BL between the portion of the outer surface of each external terminal 13 that is covered by the sealing material 15 and the portion that is not covered by the sealing material 15. On the other hand, the second barrier film 16C does not cover a portion of the tip side of each external terminal 13. The edge of the second barrier film 16C coincides with the edge of the first barrier film 16B and the edge of the organic film 16A. In other words, the first barrier film 16B directly covers the entire outer surface of the first barrier film 16B, while not protruding outward from the first barrier film 16B and the organic film 16A.

[0023] As shown in Figure 3, the average thickness of the first barrier film 16B is smaller than the average thickness of the organic film 16A and the average thickness of the second barrier film 16C. Furthermore, the average thickness of the first barrier film 16B is 50 nm or less. In this first embodiment, the average thickness of the first barrier film 16B is approximately 40 nm. On the other hand, the average thickness of the organic film 16A and the average thickness of the second barrier film 16C are both 1 μm or more. Note that in Figures 2 and 3, the thickness Tb of the first barrier film 16B is exaggerated in the illustration.

[0024] The film thickness Ta of the organic film 16A can be measured as follows. First, as shown in Figure 3, a cross-section including the outer surface S1 of the sealant 15 and the outer surface S2 of the organic film 16A, and perpendicular to the outer surface S1 of the sealant 15, is photographed with an electron microscope. Then, an arbitrary location is identified on the surface of the organic film 16A facing the sealant 15. The surface of the organic film 16A facing the sealant 15 can be considered identical to the outer surface S1 of the sealant 15. The shortest distance from this arbitrary location to the outer surface S2 of the organic film 16A is taken as the film thickness Ta of the organic film 16A at that arbitrary location. The film thickness Tb of the first barrier film 16B and the film thickness of the second barrier film 16C can be measured using the same method.

[0025] Furthermore, the average film thickness of the organic film 16A can be measured as follows. As described above, a cross-section including the outer surface S1 of the sealing material 15 and the outer surface S2 of the organic film 16A, and perpendicular to the outer surface S1 of the sealing material 15, is photographed with an electron microscope. Next, the observation range in the direction along the outer surface S1 of the sealing material 15 is identified from the captured electron microscope image. The observation range at this time is 10 μm or more. This observation range may be 10 μm or more continuously, or the sum of ranges at multiple different locations may be 10 μm or more. Then, the area of ​​the organic film 16A within the observation range is measured on the electron microscope image using image processing or the like. The value obtained by dividing the calculated area by the length of the observation range is taken as the average film thickness of the organic film 16A. The average film thickness of the first barrier film 16B and the average film thickness of the second barrier film 16C can be measured using the same method.

[0026] The minimum thickness Tb of the first barrier film 16B is 15 nm or more. The maximum thickness Tb of the first barrier film 16B is 65 nm or less. The minimum and maximum values ​​of the film thickness Tb of the first barrier film 16B can be measured as follows. First, a cross-section including the outer surface S2 of the organic film 16A and the outer surface S3 of the first barrier film 16B, and perpendicular to the outer surface S2 of the organic film 16A, is photographed with an electron microscope. Next, the observation range in the direction along the outer surface S1 of the sealing material 15 is identified from the photographed electron microscope image. The observation range at this time is set to 10 μm or more. The minimum value of the film thickness Tb of the first barrier film 16B within this observation range is considered to be the minimum value of the total film thickness Tb of the first barrier film 16B. Similarly, the maximum value of the film thickness Tb of the first barrier film 16B within the observation range is considered to be the maximum value of the total film thickness Tb of the first barrier film 16B.

[0027] As shown in Figure 3, the surface roughness of the outer surface S2 of the organic film 16A is smaller than the surface roughness of the surface covered by the organic film 16A and in contact with the organic film 16A. In this first embodiment, the surface covered by the organic film 16A and in contact with the organic film 16A is the outer surface S1 of the sealing material 15. Preferably, the surface roughness of the outer surface S2 of the organic film 16A is 50% or less of the surface roughness of the outer surface S1 of the sealing material 15.

[0028] The surface roughness of the outer surface S2 of the organic film 16A can be measured as the arithmetic mean roughness. Specifically, a cross-section including the outer surface S2 of the organic film 16A and perpendicular to the outer surface S1 of the sealant 15 is photographed with an electron microscope. The arithmetic mean roughness of the outer surface S2 of the organic film 16A, which is represented linearly on this electron microscope image, can be measured using a known calculation method. The arithmetic mean roughness is sometimes referred to as "Sa (ISO 25178)" or "Ra (JIS B 0601-2001)". The surface roughness of the outer surface S1 of the sealant 15 can be measured in the same manner.

[0029] <Manufacturing method of the first embodiment> A method for manufacturing the electronic element 10 of the first embodiment will be described. As shown in Figure 4, the manufacturing method includes a parts preparation step S11, a masking step S12, a first film deposition step S13, a second film deposition step S14, a third film deposition step S15, and a mask removal step S16.

[0030] In this manufacturing method, first, a parts preparation step S11 is performed. In the parts preparation step S11, a parts body 11 covered with a sealing material 15 is prepared. Therefore, the objects to be processed at this stage include the base body 12 of the parts body 11, each external terminal 13, and the sealing material 15.

[0031] Next, the masking process S12 is performed. In the masking process S12, a portion of each external terminal 13 is covered with masking tape. Specifically, as shown in Figure 2, a portion of each external terminal 13 from the tip is designated as a mask region M, and this mask region M is covered with masking tape. As the masking tape, for example, a tape made of a polyimide resin film with a heat-resistant silicone adhesive applied to the surface of the film can be used. Note that in Figure 2, the mask region M in the electronic element 10 is shown virtually.

[0032] Next, as shown in Figure 4, the first film formation step S13 is performed. In the first film formation step S13, an organic film 16A is formed on the object to be processed by a so-called dip-coating method. Specifically, the part body 11, which is covered with the sealing material 15 and is the object to be processed, is immersed in a coating solution in which uncured silicon-containing polyimide is dispersed in a solvent. At this time, only the base ends of each external terminal 13 of the part body 11 are in contact with the coating solution. Then, the object to be processed is removed from the coating solution. After that, the object to be processed is heated for several hours. The heating temperature at this time is approximately 100 degrees Celsius or higher and 200 degrees Celsius or lower. This causes the silicon-containing polyimide to harden and the solvent and other substances to volatilize. As a result, an organic film 16A is formed on the outer surface S1 of the sealing material 15.

[0033] Next, the second film deposition process S14 is performed. In the second film deposition process S14, a first barrier film 16B is deposited on the object to be processed by the so-called atomic layer deposition (ALD) method. As a result, the first barrier film 16B, mainly composed of aluminum oxide, is formed on the outer surface S2 of the organic film 16A and on a portion of the outer surface of each external terminal 13. As mentioned above, the mask region M of each external terminal 13 is covered with masking tape. Therefore, the first barrier film 16B is not deposited on the mask region M of each external terminal 13. On the other hand, the organic film 16A covers only a portion of the base end side of each external terminal 13. Therefore, immediately before the second film deposition process S14, there is an exposed portion of each external terminal 13 between the sealing material 15 and the mask region M. The first barrier film 16B is also deposited on this exposed portion of each external terminal 13.

[0034] Next, the third film formation step S15 is performed. In the third film formation step S15, a second barrier film 16C is formed on the object to be treated by a method known as chemical vapor deposition (CVD). In this embodiment, the second barrier film 16C is formed by a thermal CVD method, which forms a film on the object to be treated by a chemical reaction at high temperature. As a result, a second barrier film 16C, mainly composed of parylene, is formed on the outer surface S3 of the first barrier film 16B. As with the first barrier film 16B, the second barrier film 16C is not formed in the mask region M of each external terminal 13.

[0035] Next, the mask removal process S16 is performed. In the mask removal process S16, the masking tape attached in the masking process S12 is removed from each external terminal 13. As a result, the mask area M of each external terminal 13 is directly exposed to the outside, and the electronic element 10 is manufactured. The exposed portion of each external terminal 13 is connected to an electrode on the substrate, for example, with solder.

[0036] <Effects of the First Embodiment> The electronic element 10 of the first embodiment provides the following effects. (1-1) The first barrier film 16B is expected to have barrier properties corresponding to its average film thickness. However, there may be localized areas in the first barrier film 16B that are extremely thin compared to the average film thickness. In this case, the barrier properties will be low in the areas where the film thickness Tb is thin, and the first barrier film 16B as a whole may not be able to exhibit the barrier properties expected according to its average film thickness. This phenomenon is particularly pronounced when the average film thickness of the first barrier film 16B is small.

[0037] In this regard, in the first embodiment described above, the minimum value of the film thickness Tb of the first barrier film 16B is 15 nm or more, and the maximum value of the film thickness Tb of the first barrier film 16B is 65 nm or less. That is, even though the first barrier film 16B is a thin film with a film thickness Tb of 65 nm or less, a film thickness Tb of at least 15 nm is ensured. Therefore, the possibility of obtaining barrier properties corresponding to the average film thickness of the first barrier film 16B is increased.

[0038] Furthermore, while the barrier properties of the first barrier film 16B generally improve as the film thickness Tb increases, the rate of improvement in barrier properties decreases and plateaus when the film thickness Tb approaches 65 nm. Moreover, when the film thickness Tb exceeds 65 nm, the barrier properties of the first barrier film 16B actually decrease. Therefore, in the first embodiment described above, the film thickness of the first barrier film 16B is within a suitable range that can exhibit high barrier properties.

[0039] (1-2) In the first embodiment, the organic film 16A and the first barrier film 16B cover the edge portion 12D of the base body 12. This edge portion 12D is the so-called corner portion of the base body 12. By covering this edge portion 12D of the base body 12 with the organic film 16A, the corner of the base body 12 becomes a shape that is beveled to some extent by the organic film 16A. The presence of the first barrier film 16B on the organic film 16A prevents the film thickness Tb of the first barrier film 16B in the portion that covers the edge portion 12D from becoming extremely small.

[0040] (1-3) In the first embodiment, a sealing material 15 made of synthetic resin is provided between the component body 11 and the organic film 16A. This sealing material 15 also prevents moisture and other substances from entering the component body 11.

[0041] (1-4) In the first embodiment, a boundary BL exists between the outer surface of each external terminal 13 and the portion covered by the sealing material 15. At this boundary BL, there is a possibility that moisture and the like may penetrate through the interface between the outer surface of the external terminal 13 and the sealing material 15. In the first embodiment, the organic film 16A and the first barrier film 16B cover this boundary BL, so that moisture and the like can not penetrate through the boundary BL.

[0042] (1-5) In the first embodiment, the average thickness of the first barrier film 16B is 50 nm or less, and is smaller than the average thickness of the organic film 16A. In other words, the first barrier film 16B is a very thin film. Therefore, the presence of the first barrier film 16B can suppress an increase in the overall size of the electronic device 10.

[0043] (1-6) In the first embodiment, a second barrier film 16C is further provided that covers the outer surface S3 of the first barrier film 16B. As a result, an interface is formed between the first barrier film 16B and the second barrier film 16C within the protective film 16. With such an interface in place, even if moisture or the like penetrates into the second barrier film 16C, the moisture or the like spreads on the interface and is less likely to penetrate further into the first barrier film 16B. In other words, in addition to the barrier properties of the second barrier film 16C itself, an improvement in barrier properties can be expected due to the presence of an interface between the two barrier films.

[0044] (1-7) In the first embodiment, the surface roughness of the outer surface S2 of the organic film 16A is smaller than the surface roughness of the outer surface S1 of the sealant 15. That is, the organic film 16A flattens the surface irregularities of the sealant 15. Then, by forming the first barrier film 16B on the flat outer surface S2 of the organic film 16A, variations in the film thickness Tb of the first barrier film 16B at each location can be suppressed.

[0045] (1-8) In the first embodiment, atomic layer deposition is used as the film deposition method in the second film deposition step S14. Atomic layer deposition can produce a dense and thin film with a uniform film thickness. That is, it is particularly suitable as a film deposition method for the first barrier film 16B.

[0046] (1-9) In the first embodiment, chemical vapor deposition is used as the film deposition method in the third film deposition step S15. Chemical vapor deposition is more likely to produce thicker films than atomic layer deposition. Therefore, it is particularly suitable as a film deposition method for obtaining a thick, highly barrier-oriented second barrier film 16C.

[0047] <Configuration of the second embodiment> Embodiments of the package component 20 as an electronic module will be described. In the second embodiment, components common to the first embodiment may be denoted by the same reference numerals, and their descriptions may be omitted or simplified.

[0048] As shown in Figure 5, the package component 20 comprises a wiring board 21 as a specific component, a solder resist 22 as a sealing material, and a resin molded body 23. The wiring board 21 further comprises a board body 21A and a plurality of wirings 21B. The board body 21A is plate-shaped. The material of the board body 21A is an insulating synthetic resin such as phenolic resin or epoxy resin. Each wiring 21B is located on the first main surface S5 of the board body 21A. The material of each wiring 21B is a conductive metal. Therefore, the wiring 21B are metal components. Although not shown in the figures, the wiring board 21 has a plurality of wirings inside the board body 21A and on the second main surface S6 opposite to where the wiring 21B are located. The above wirings 21B are connected to the wirings on the second main surface S6 via the wiring inside the board body 21A. The wiring board 21 is sometimes referred to as a printed circuit board or the like.

[0049] The solder resist 22 is made of an insulating synthetic resin. The solder resist 22 covers the first main surface S5 of the substrate body 21A and a portion of the wiring 21B. Specifically, the solder resist 22 covers the entire area of ​​the first main surface S5 of the substrate body 21A where wiring 21B is not present. Also, as shown in Figure 6, at the ends of the wiring 21B, the solder resist 22 covers a portion of the outer surface of the wiring 21B, including the outer edge of the wiring 21B. Therefore, the wiring 21B has portions that are not covered by the solder resist 22.

[0050] As shown in Figure 5, the resin molded body 23 is located on the second main surface S6 of the substrate body 21A. Although not shown in the figure, the resin molded body 23 is composed of various elements mounted on the second main surface S6 of the substrate body 21A and an insulating synthetic resin covering these elements. The resin molded body 23 is approximately rectangular parallelepiped in shape. The various elements of the resin molded body 23 are connected to the wiring 21B on the first main surface S5 via wiring on the second main surface S6 and wiring inside the substrate body 21A.

[0051] As shown in Figure 5, the package component 20 is equipped with a protective film 16. The protective film 16 covers the outer surface of the resin molded body 23. The protective film 16 also covers a portion of the outer surface of the wiring 21B of the wiring board 21, and the outer surface of the solder resist 22. More specifically, the protective film 16 covers the boundary BL between the portion of the outer surface of the wiring 21B that is covered by the solder resist 22 and the portion that is not covered by the solder resist 22. On the other hand, the protective film 16 does not cover a portion of the outer surface of the wiring 21B. The portion of the wiring 21B that is not covered by the protective film 16 functions as a terminal for electrically connecting other electronic elements, substrates, etc.

[0052] As shown in Figure 6, the protective film 16 comprises, in order from the side of the object to which the protective film 16 is applied, an organic film 16A, a first barrier film 16B, and a second barrier film 16C. The relationship between the film thickness and surface roughness of each of these protective films 16 is the same as in the first embodiment.

[0053] <Effects of the second embodiment> The package component 20 of the second embodiment provides the same effects as (1-1), (1-5) to (1-9) of the first embodiment, in addition to the following effects.

[0054] (2-1) In the second embodiment, there is a boundary BL between the outer surface of the wiring 21B and the portion covered by the solder resist 22. At this boundary BL, there is a possibility that moisture or the like may penetrate through the interface between the outer surface of the wiring 21B and the solder resist 22. In the second embodiment, the protective film 16 covers this boundary BL, so that moisture or the like can penetrate through the boundary BL.

[0055] <Configuration of the third embodiment> An embodiment of the mounting substrate 30 as an electronic module will be described. Here, "mounting substrate" refers to any substrate on which electronic elements, chips, etc., are mounted. In the third embodiment, components common to the first embodiment may be denoted by the same reference numerals, and their descriptions may be omitted or simplified.

[0056] As shown in Figure 7, the mounting substrate 30 comprises a wiring board 31 as a specific component, a solder resist 32 as a sealing material, an electronic element 33, and a bonding material 35. The wiring board 31 further comprises a board body 31A and a plurality of wirings 31B. The board body 31A is plate-shaped. The material of the board body 31A is an insulating synthetic resin such as phenolic resin or epoxy resin, or silicone. Each wiring 31B is located on the main surface S7 of the board body 31A. The material of each wiring 31B is a conductive metal. Therefore, the wiring 31B is a metal component.

[0057] The solder resist 32 is made of an insulating synthetic resin. The solder resist 32 covers the main surface S7 of the substrate body 31A and a portion of the wiring 31B. Specifically, the solder resist 32 covers the entire area of ​​the main surface S7 of the substrate body 31A where there is no wiring 31B. Also, as shown in Figure 8, at the ends of the wiring 31B, the solder resist 32 covers a portion of the outer surface of the wiring 31B, including the outer edge of the wiring 31B. Therefore, the wiring 31B has portions that are not covered by the solder resist 32. The portions of the wiring 31B that are not covered by the solder resist 32 function as terminals for electrically connecting electronic elements 33 and the like.

[0058] As shown in Figure 7, the electronic element 33 is mounted on the wiring board 31. Specifically, the bonding material 35 bonds the external terminals of the electronic element 33 to the terminal portion of the wiring 31B that is not covered by the solder resist 32. Note that the external terminals of the electronic element 33 are not shown in Figure 7. The bonding material 35 is a conductive adhesive or solder. The electronic element 33 is spaced apart from the solder resist 32 on the wiring board 31. Therefore, there is a small gap between the electronic element 33 and the solder resist 32. Note that the electronic element 33 here may have a separate protective film 16, as in the electronic element 10 of the first embodiment, or it may not have a protective film 16.

[0059] As shown in Figure 7, the mounting substrate 30 is equipped with a protective film 16. The protective film 16 covers the outer surface of the electronic element 33. More specifically, the protective film 16 covers all areas of the outer surface of the electronic element 33 where the bonding material 35 is not present. The protective film 16 also covers all areas of the outer surface of the wiring 31B where the solder resist 32 and bonding material 35 are not present. The protective film 16 covers the entire outer surface of the solder resist 32. As a result, the protective film 16 covers the boundary BL between the portion of the outer surface of the wiring 31B that is covered by the solder resist 32 and the portion that is not covered by the solder resist 32. Furthermore, the protective film 16 covers the entire side surface of the bonding material 35. In this way, the protective film 16 covers the entire area of ​​the wiring 31B of the wiring substrate 31, the surface of the solder resist 32 facing the electronic element 33, the electronic element 33, and the outer surface of the bonding material 35 that is exposed to the outside.

[0060] As shown in Figure 8, the protective film 16 comprises, in order from the side of the object to which the protective film 16 is applied, an organic film 16A, a first barrier film 16B, and a second barrier film 16C. The relationship between the film thickness and surface roughness of each of these protective films 16 is the same as in the first embodiment.

[0061] <Effects of the Third Embodiment> The mounting substrate 30 of the third embodiment provides the same effects as (1-1), (1-5) to (1-9) of the first embodiment, in addition to the following effects.

[0062] (3-1) In the third embodiment, there is a boundary BL between the outer surface of the wiring 31B and the portion covered by the solder resist 32. At this boundary BL, there is a possibility that moisture or the like may penetrate through the interface between the outer surface of the wiring 31B and the solder resist 32. In the third embodiment, the protective film 16 covers this boundary BL, so that moisture or the like can penetrate through the boundary BL.

[0063] (3-2) In the third embodiment, the portion of the outer surface of the electronic element 33 facing the solder resist 32, and the portion of the outer surface of the solder resist 32 facing the electronic element 33 are also covered with the protective film 16. Furthermore, the sides of the bonding material 35 are also covered with the protective film 16. As a result, the entire wiring board 31, solder resist 32, electronic element 33, and bonding material 35 are covered with a continuous protective film 16. By covering the entire structure with a continuous protective film 16 in this way, high barrier performance can be achieved.

[0064] <Configuration of the 4th embodiment> An embodiment of the quartz oscillator 40 as an electronic module will be described. In the fourth embodiment, components common to the first embodiment may be denoted by the same reference numerals, and their descriptions may be omitted or simplified.

[0065] As shown in Figure 9, the crystal oscillator 40 comprises a ceramic substrate 41 as a first component, a crystal element 42, a metal cap 43 as a second component, and an adhesive 45. These ceramic substrate 41, crystal element 42, metal cap 43, and adhesive 45 constitute the oscillator body 40A as a specific component.

[0066] The ceramic substrate 41 further comprises a substrate body 41A and a plurality of wirings 41B. The substrate body 21A is plate-shaped. The material of the substrate body 21A is ceramic, specifically silicon. Each wiring 41B is located on the first main surface S8 of the substrate body 21A. The material of each wiring 41B is a conductive metal. Although not shown in the figures, the ceramic substrate 41 has a plurality of wirings inside the substrate body 41A and on the second main surface S9 opposite to where the wirings 41B are located. The above wirings 41B are connected to the wirings on the second main surface S9 via the wiring inside the substrate body 41A.

[0067] The quartz element 42 is an element that emits a signal of a specified frequency by utilizing the piezoelectric effect of quartz. Note that peripheral circuits for supplying power to the quartz element 42 may be mounted on the main body 41A of the ceramic substrate 41.

[0068] Examples of materials for the metal cap 43 include stainless steel and aluminum alloy. The metal cap 43 is box-shaped with one side closed. In other words, the shape of the metal cap 43 is a box with a bottom. The opening of the metal cap 43 faces the ceramic substrate 41. The metal cap 43 surrounds the crystal element 42 from the outside.

[0069] As shown in Figure 10, the opening edge 43A of the metal cap 43 is joined to the second main surface S9 of the substrate body 41A. Specifically, the adhesive 45 joins the opening edge 43A of the metal cap 43 to the second main surface S9 of the substrate body 41A. The adhesive 45 extends over the entire opening edge 43A of the metal cap 43. The material of the adhesive 45 is a synthetic resin.

[0070] As shown in Figure 9, the crystal oscillator 40 is equipped with a protective film 16. The protective film 16 covers the entire portion of the substrate body 41A that is not surrounded by the metal cap 43. However, the protective film 16 does not cover a portion of the wiring 41B. The portion of the wiring 41B not covered by the protective film 16 functions as a terminal for electrical connection to the substrate or the like.

[0071] Furthermore, the protective film 16 covers the entire outer surface of the metal cap 43. In addition, the protective film 16 covers the side of the adhesive 45 opposite to the space S partitioned by the metal cap 43. Therefore, the protective film 16 covers the boundary BL between the opening edge 43A, which is the part of the metal cap 43 covered by the adhesive 45, and the part that is not covered by the adhesive 45. Also, the protective film 16 covers the boundary BL between the part of the second main surface S9 of the ceramic substrate 41 covered by the adhesive 45 and the part that is not covered by the adhesive 45. In this way, the protective film 16 covers the entire surface of the ceramic substrate 41, the metal cap 43, and the adhesive 45 opposite to the space S, except for a part of the outer surface of the wiring 41B.

[0072] As shown in Figure 10, the protective film 16 comprises, in order from the object to which it is laminated, an organic film 16A, a first barrier film 16B, and a second barrier film 16C. The relationship between the film thickness and surface roughness of each of these protective films 16 is the same as in the first embodiment.

[0073] <Effects of the 4th Embodiment> The quartz oscillator 40 of the fourth embodiment provides the same effects as (1-1), (1-5) to (1-9) of the first embodiment, in addition to the following effects.

[0074] (4-1) In the fourth embodiment, there is a boundary BL between the opening edge 43A, which is the outer surface of the metal cap 43 covered with adhesive 45, and the portion not covered with adhesive 45. At this boundary BL, there is a possibility that moisture or the like may penetrate through the interface between the outer surface of the metal cap 43 and the adhesive 45. In the fourth embodiment, the protective film 16 covers this boundary BL, so that moisture or the like may penetrate through the boundary BL can be prevented. Similarly, the protective film 16 covers the boundary BL of the second main surface S9 of the ceramic substrate 41 between the portion covered with adhesive 45 and the portion not covered with adhesive 45. Therefore, moisture or the like may penetrate the ceramic substrate 41 through the boundary BL can be prevented.

[0075] <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.

[0076] The electronic modules to which the protective film 16 is applied are not limited to those exemplified in the first to fourth embodiments. The technology relating to the protective film 16 described above can be applied to a variety of things, such as passive elements, active elements, substrates, mounting substrates combining these, and assemblies in which multiple mounting substrates are integrated.

[0077] In the first embodiment, the material and shape of the base body 12 are merely examples. For example, the base body 12 may be cylindrical or have other shapes. Depending on the shape of the base body 12, it may not have a clear ridge portion 12D. Even if the base body 12 does not have such a ridge portion 12D, the technology relating to the protective film 16 of the above embodiment can be applied. Furthermore, in the first embodiment, the shape and number of external terminals 13 can also be changed as appropriate.

[0078] In the protective film 16 of the first embodiment, the edges of the organic film 16A, the first barrier film 16B, and the second barrier film 16C do not necessarily coincide. For example, a part of the first barrier film 16B may protrude outward relative to the organic film 16A, or the edge of the first barrier film 16B may be located inward relative to the edge of the organic film 16A. The same applies to the other films. When the positions of the edges of each film are shifted in this way, masking and removal of the masking can be performed at each film deposition step.

[0079] In the first embodiment, the edge of the sealing material 15 may coincide with the edge of the protective film 16. If a portion of each external terminal 13 is masked during the manufacturing process, as in the first embodiment, the edge of the sealing material 15 will coincide with the edge of the protective film 16 if the sealing material 15 is formed up to the masked portion.

[0080] In the first embodiment, the sealing material 15 may be omitted. In this case, the protective film 16 directly covers the base body 12 of the component body 11. In this modified example, it is preferable that the surface roughness of the outer surface S2 of the organic film 16A is smaller than the surface roughness of the outer surface of the base body 12, which is the surface covered by the organic film 16A of the protective film 16 and the surface in contact with the organic film 16A.

[0081] The material of the organic film 16A is not limited to those exemplified in the above embodiment, as long as it mainly consists of organic components, and can be changed as appropriate. The material should be selected appropriately according to the barrier properties required for the organic film 16A.

[0082] The surface roughness of the outer surface S2 of the organic film 16A may be about the same as, or greater than, the surface roughness of the surface covered by the organic film 16A. The material of the first barrier film 16B is not limited to those exemplified in the above embodiment, as long as it mainly consists of inorganic components, and can be changed as appropriate. The material should be selected as appropriate according to the barrier properties required for the first barrier film 16B. However, from the viewpoint of ensuring insulation to the external terminal 13, an insulating material among the inorganic components is preferred.

[0083] The material of the second barrier film 16C is not specified. In terms of barrier properties against components different from those that the first barrier film 16B can block, it is preferable that the material of the second barrier film 16C is different from the material of the first barrier film 16B. However, even if the material of the second barrier film 16C is the same as the material of the first barrier film 16B, an interface will be formed between the two barrier films. Therefore, even if they are made of the same material, having both the first barrier film 16B and the second barrier film 16C may increase the barrier properties.

[0084] The second barrier film 16C may be omitted. The presence or absence of the second barrier film 16C should be chosen considering the barrier properties that can be achieved with the organic film 16A and the first barrier film 16B. The protective film 16 may have an additional barrier layer outside the second barrier film 16C. For example, the first barrier film 16B and the second barrier film 16C outside of it may form a pair of multilayer barrier layers. Multiple pairs of these multilayer barrier layers may be present in order from the organic film 16A side. Specifically, as shown in Figure 11, the protective film 16 may have an organic film 16A, a first barrier film 16B, a second barrier film 16C, a first barrier film 116B, and a second barrier film 116C, which are stacked in order from the sealing material 15 side. In Figure 11, a five-layer protective film 16 is described as an example of a modification of the first embodiment, but the protective film 16 can be similarly modified in other embodiments.

[0085] • In addition to the first barrier film 16B, there may be other barrier films made of the same material as the first barrier film 16B. Furthermore, the other barrier film made of the same material as the first barrier film 16B may directly cover the first barrier film 16B. In this case, the portion inside the interface between the first barrier film 16B and the other barrier film is the "first barrier film 16B directly covering the organic film 16A". Also, there may be barrier films of a different type from the first barrier film 16B and the second barrier film 16C.

[0086] The average thickness of the first barrier film 16B is not limited to 50 nm or less as exemplified in the first embodiment. The minimum value of the thickness Tb of the first barrier film 16B is 15 nm or more, and the maximum value of the thickness Tb of the first barrier film 16B is 65 nm or less. Therefore, the average thickness of the first barrier film 16B can take a value between 15 nm and 65 nm.

[0087] The average film thickness of the first barrier film 16B does not necessarily have to be smaller than the average film thickness of the organic film 16A and the average film thickness of the second barrier film 16C. In other words, the average film thickness of the organic film 16A and the average film thickness of the second barrier film 16C may be smaller than the average film thickness of the first barrier film 16B.

[0088] The measurement methods for the average film thickness, film thickness, minimum and maximum film thickness, and surface roughness of each film in the first embodiment are merely illustrative. If there are unified measurement methods established by various organizations or industries, those methods should be followed. Alternatively, measurement methods that are conventionally used depending on the specifications of the equipment may be adopted.

[0089] The manufacturing method for the electronic module, particularly the method for forming the protective film 16, is not limited to the manufacturing method exemplified in the above embodiment. For example, in each of the first film formation step S13 to the third film formation step S15, film formation may be carried out by methods other than those exemplified in the above embodiment. Furthermore, two or more of the first film formation steps S13 to the third film formation steps S15 may be the same film formation method.

[0090] Furthermore, the masking step S12 may be omitted. In this case, for example, a portion of the protective film 16 covering each external terminal 13 may be removed by etching, thereby exposing a portion of the outer surface of the external terminal 13.

[0091] The configuration of the package component 20 in the second embodiment is an example and can be modified as appropriate. For example, multiple resin molded bodies 23 may be present on the same wiring board 21. In the second embodiment, the solder resist 22 as a sealing material may be omitted. In this case, the protective film 16 directly covers the first main surface S5 of the substrate body 21A. In this modified example, it is preferable that the surface roughness of the outer surface S2 of the organic film 16A is smaller than the surface roughness of the first main surface S5 of the substrate body 21A, which is the surface covered by the organic film 16A of the protective film 16 and the surface in contact with the organic film 16A.

[0092] The configuration of the mounting board 30 in the third embodiment is an example and can be modified as appropriate. For example, multiple electronic elements 33 may be mounted on the same wiring board 31. Furthermore, electronic elements 33 may be mounted not only on the main surface S7 of the wiring board 31, but also on the main surface opposite to the main surface S7. Furthermore, package components 20, as in the second embodiment, may be mounted in place of or in addition to the electronic elements 33.

[0093] In the third embodiment, the electronic element 33 may be sealed from the outside with a synthetic resin. In this case, the synthetic resin may be present on the outside of the electronic element 33 that is covered with the protective film 16, or the protective film 16 may be present so as to cover the synthetic resin that seals the electronic element 33.

[0094] In the third embodiment, the solder resist 32 as a sealing material may be omitted. In this case, the protective film 16 directly covers the main surface S7 of the substrate body 31A. In this modified example, it is preferable that the surface roughness of the outer surface S2 of the organic film 16A is smaller than the surface roughness of the main surface S7 of the substrate body 31A, which is the surface covered by the organic film 16A of the protective film 16 and the surface in contact with the organic film 16A.

[0095] Regarding the fourth embodiment, the above technology concerning the protective film 16 may be applied to an element other than the quartz oscillator 40, provided that a metal cap 43 is bonded to the ceramic substrate 41.

[0096] • In each embodiment, the portion covered by the protective film 16 can be changed as appropriate. For example, in the first embodiment, the protective film 16 may cover only the outer surface of the base body 12, or only the outer surface of the external terminal 13. It is preferable that the boundary portion of different members is covered by the protective film 16, as in the boundary BL in each embodiment.

[0097] <Note> The technical concepts that can be understood from the above embodiments and modified examples are described below. [1] An electronic module comprising a specific component, an organic film mainly composed of organic components covering the outer surface of the specific component, and a first barrier film mainly composed of inorganic components covering the organic film, wherein the minimum thickness of the first barrier film is 15 nm or more, and the maximum thickness of the first barrier film is 65 nm or less.

[0098] [2] The electronic module according to [1], wherein the specific component has, as part of the outer surface, a first plane and a second plane adjacent to the first plane and extending in a direction intersecting the first plane, and the organic film and the first barrier film cover the ridge between the first plane and the second plane.

[0099] [3] The electronic module according to [1] or [2], having a sealing material made of synthetic resin between the specific component and the organic film. [4] The electronic module according to [3], wherein the specific component has a metal member, the sealing material covers a part of the outer surface of the metal member, and the organic film and the first barrier film cover the boundary between the portion of the metal member covered by the sealing material and the portion not covered by the sealing material.

[0100] [5] The electronic module according to any one of [1] to [4], wherein the average thickness of the first barrier film is 50 nm or less and is smaller than the average thickness of the organic film. [6] The electronic module according to any one of [1] to [5], further comprising a second barrier film covering the outer surface of the first barrier film.

[0101] [7] The surface roughness of the outer surface of the organic film is smaller than the surface roughness of the surface covered by the organic film and in contact with the organic film. [1] to [6] The electronic module according to any one of these.

[0102] [8] The specific component further comprises a first member and a second member joined to the first member via an adhesive, wherein the organic film and the first barrier film cover the first member, the second member and the adhesive, as described in any one of [1] to [5].

[0103] [9] A method for manufacturing an electronic module, comprising: a first film formation step of forming an organic film mainly composed of organic components on the outer surface of a specific component; and a second film formation step of forming a first barrier film mainly composed of inorganic components on the outer surface of the organic film by atomic layer deposition, wherein in the second film formation step, the first barrier film is formed such that the minimum thickness of the first barrier film is 15 nm or more and the maximum thickness of the first barrier film is 65 nm or less.

[0104]

[10] The method for manufacturing an electronic module according to [9], further comprising a third film formation step of forming a second barrier film mainly composed of parylene on the outer surface of the first barrier film by chemical vapor deposition. [Explanation of Symbols]

[0105] 11…Main body of the part 16...Protective film 16A…Organic film 16B...First barrier film 16C…Second barrier membrane 21…Wiring board 31…Wiring board 40…Transducer body

Claims

1. Specific parts and An organic film, mainly composed of organic components, covers the outer surface of the aforementioned specific part, A first barrier film, mainly composed of inorganic components, directly covers the aforementioned organic film, Equipped with, The minimum thickness of the first barrier film is 15 nm or more, and the maximum thickness of the first barrier film is 65 nm or less. Electronic module.

2. The aforementioned specific component has, as part of its outer surface, a first plane and a second plane adjacent to the first plane and extending in a direction intersecting the first plane. The organic film and the first barrier film cover the ridge between the first plane and the second plane. The electronic module according to claim 1.

3. A sealing material mainly composed of synthetic resin is provided between the specified component and the organic film. The electronic module according to claim 1.

4. The aforementioned specific part has a metal member, The sealing material covers a portion of the outer surface of the metal member, The organic film and the first barrier film cover the boundary between the portion of the metal member covered by the sealing material and the portion not covered by the sealing material. The electronic module according to claim 3.

5. The average thickness of the first barrier film is 50 nm or less, and is smaller than the average thickness of the organic film. The electronic module according to claim 1.

6. The first barrier film further comprises a second barrier film covering the outer surface of the first barrier film. The electronic module according to claim 1.

7. The surface roughness of the outer surface of the organic film is smaller than the surface roughness of the surface covered by the organic film and in contact with the surface. The electronic module according to claim 1.

8. The aforementioned specific component further comprises a first member and a second member joined to the first member via an adhesive, The organic film and the first barrier film cover the first member, the second member, and the adhesive. The electronic module according to claim 1.

9. A first film formation step involves forming an organic film mainly composed of organic components on the outer surface of a specific part, A second film formation step involves forming a first barrier film, mainly composed of inorganic components, on the outer surface of the aforementioned organic film by atomic layer deposition. It has, In the second film formation step, the first barrier film is formed such that the minimum thickness of the first barrier film is 15 nm or more, and the maximum thickness of the first barrier film is 65 nm or less. A method for manufacturing electronic modules.

10. The invention further comprises a third film formation step of forming a second barrier film, mainly composed of parylene, on the outer surface of the first barrier film by chemical vapor deposition. A method for manufacturing an electronic module according to claim 9.

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