Resin multilayer substrate and electronic device

Abstract

The invention provides a resin multilayer substrate and an electronic device, which ensure the adhesion between a carrying part and a multilayer substrate part, and inhibit the deformation of a rigid part formed by the multilayer substrate part and the carrying part and the generation of cracks at the boundary between a flexible part and the rigid part. The resin multilayer substrate is provided with a multilayer substrate part (101) and a mounting part (201), the resin layer of the multilayer substrate part (101) and the resin layer of the mounting part (201) are both layers formed from a crystalline thermoplastic resin having the same first component, and the resin layer of the multilayer substrate part (101) and the resin layer of the mounting part (201) are formed from a crystalline thermoplastic resin having the same first component. In a 1st-up map when differential scanning calorimetry (DSC) is performed at a temperature rise rate of 10 DEG C / min, there is a difference in endothermic peak temperatures occurring at the beginning of temperature rise, the endothermic peak temperature of the resin layer of the multilayer substrate part (101) is lower than the endothermic peak temperature of the resin layer of the mounting part (201), and the resin layer of the multilayer substrate part (101) and the resin layer of the mounting part (201) are directly bonded.

Description

Technical Field

[0001] The present invention relates to a resin multilayer substrate including a multilayer substrate portion formed by laminating resin layers and a mounting portion mounted on the multilayer substrate portion or having a shape to be mounted on the multilayer substrate portion, and an electronic device including the resin multilayer substrate. Background Art

[0002] Patent Document 1 discloses a resin multilayer substrate including a plurality of resin layers, a conductor layer attached to one surface of the resin layers, and an interlayer connection conductor formed inside a predetermined resin layer.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: International Publication No. 2017 / 051649

[0006] If the structure forms regions with locally different thicknesses in the stacking direction due to the difference in the number of stacked resin layers with a conductor layer attached, the thicker portion can have a predetermined electronic component function.

[0007] However, when bonding dissimilar materials, ensuring close contact between the multilayer substrate and the mounted components is difficult. Furthermore, the multilayer substrate and the mounted components formed the rigid portion, while the rest of the multilayer substrate itself is the flexible portion. Therefore, while this flexible portion can be deformed, the rigid portion may also deform with it. Furthermore, stress tends to concentrate at the boundary between the flexible and rigid portions (at the base of the rigid portion), causing cracks to form at this boundary, for example, due to bending of the flexible portion. Summary of the Invention

[0008] Problems to be solved by the invention

[0009] Therefore, the object of the present invention is to provide a resin multilayer substrate that ensures the close contact between a mounting portion mounted on a multilayer substrate portion or having a shape to be mounted on a multilayer substrate portion and the multilayer substrate portion, and suppresses the deformation of a rigid portion formed by the multilayer substrate portion and the mounting portion and the generation of cracks at the boundary between the flexible portion and the rigid portion, as well as an electronic device equipped with the resin multilayer substrate.

[0010] Technical solutions to solve problems

[0011] (1) A resin multilayer substrate as an example of the present disclosure includes:

[0012] a multilayer substrate portion including a plurality of resin layers and a conductor layer attached to a predetermined resin layer among the plurality of resin layers; and

[0013] a mounting portion having a resin layer and a conductor layer formed on the resin layer, and mounted on the multi-layer substrate portion or having a shape capable of being mounted on the multi-layer substrate portion;

[0014] The resin layer of the multi-layer substrate portion and the resin layer of the mounting portion are both layers formed of a crystalline thermoplastic resin having the same first component.

[0015] In a first-up chart of differential scanning calorimetry performed at a temperature increase rate of 10°C / min, there is a difference in endothermic peak temperatures appearing at the initial temperature increase for the resin layer of the multilayer substrate portion and the resin layer of the mounting portion, with the endothermic peak temperature of the resin layer of the multilayer substrate portion being lower than the endothermic peak temperature of the resin layer of the mounting portion.

[0016] The resin layer of the multi-layer substrate portion and the resin layer of the mounting portion are directly bonded to each other.

[0017] (2) An electronic device as an example of the present disclosure is characterized by including:

[0018] the resin multilayer substrate; and

[0019] Another substrate on which the resin multilayer substrate is mounted.

[0020] (3) An electronic device as an example of the present disclosure is characterized by including:

[0021] the resin multilayer substrate; and

[0022] A housing houses the resin multilayer substrate.

[0023] Effects of the Invention

[0024] According to the present invention, a resin multilayer substrate is obtained that ensures the close contact between a multilayer substrate portion and a mounting portion relative to the multilayer substrate portion, and suppresses the deformation of the rigid portion formed by the multilayer substrate portion and the mounting portion, as well as the generation of cracks at the boundary between the flexible portion and the rigid portion, and an electronic device equipped with the resin multilayer substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The lower part is a cross-sectional view of the resin multilayer substrate 301 according to the first embodiment. Figure 1 The upper portion is a cross-sectional view of a state before the mounting portion 201 is mounted on the multi-layer substrate portion 101 .

[0026] Figure 2 This is a typical example of a chart showing the temperature over time and the DSC shift when differential scanning calorimetry (DSC) is performed.

[0027] Figure 3 The lower part is a cross-sectional view of the resin multilayer substrate 302 according to the second embodiment. Figure 3 The upper portion is a cross-sectional view of the resin multilayer substrate 302 during the manufacturing process.

[0028] Figure 4 The lower part is a cross-sectional view of a resin multilayer substrate 303 according to the third embodiment. Figure 4 The upper part is a top view of the mounting portion 203.

[0029] Figure 5 It is a cross-sectional view of a resin multilayer substrate 304 according to the fourth embodiment.

[0030] Figure 6 It is a cross-sectional view of a resin multilayer substrate 305 according to the fifth embodiment.

[0031] Figure 7 It is a cross-sectional view of a resin multilayer substrate 306 according to the sixth embodiment.

[0032] Figure 8 It is a cross-sectional view of a resin multilayer substrate 307 according to the seventh embodiment.

[0033] Figure 9 It is a cross-sectional view of a resin multilayer substrate 308 according to the eighth embodiment.

[0034] Figure 10 It is a cross-sectional view of an electronic device 409 according to a ninth embodiment.

[0035] Description of reference numerals:

[0036] BM…connecting conductor;

[0037] GL…ground conductor layer;

[0038] S1…Side 1;

[0039] S2…side 2;

[0040] SL, SL1, SL2, SLa, SLb... conductor patterns for signal lines;

[0041] 1…external electrode;

[0042] 2, 2a, 2b ... multi-layer substrate side pad electrodes;

[0043] 4…Interlayer connecting conductor;

[0044] 5…conductor foil;

[0045] 6, 6A, 6a, 6b…terminal electrodes;

[0046] 7…conductor layer;

[0047] 7A…Radiating electrode;

[0048] 7G…ground electrode;

[0049] 9…Filling plated through holes;

[0050] 10…resin material;

[0051] 11, 12, 13, 14, 15 ... multi-layer substrate side resin layer;

[0052] 20…adhesive layer;

[0053] 21: mounting portion side resin layer;

[0054] 24…electronic components;

[0055] 25…connector;

[0056] 27…other substrates;

[0057] 41 ... other substrate side pad electrodes;

[0058] 42 ... component side pad electrode;

[0059] 101, 102, 105, 106, 107, 108 ... a multi-layer substrate portion;

[0060] 201, 202, 203, 204, 205, 207, 208…carrying part;

[0061] 301, 302, 303, 304, 305, 306, 307, 308…resin multilayer substrate;

[0062] 409…Electronic equipment. DETAILED DESCRIPTION

[0063] Hereinafter, several specific examples are given with reference to the accompanying drawings to illustrate a plurality of ways for implementing the present invention. The same reference numerals are used for the same parts in each figure. In consideration of the ease of explanation or understanding of the key points, the specific embodiment is divided into multiple embodiments for illustration, but it is possible to omit, replace or combine parts of the structures shown in different embodiments. After the second embodiment, the description of matters common to the first embodiment is omitted, and only the differences are described. In particular, the same effects produced by the same structure are not mentioned one by one in each embodiment.

[0064] First Implementation Method

[0065] In the first embodiment, an example of a resin multilayer substrate is shown.

[0066] Figure 1 The lower part is a cross-sectional view of the resin multilayer substrate 301 according to the first embodiment. Figure 1 The upper portion is a cross-sectional view of the mounting portion 201 before mounting it on the multi-layer substrate portion 101. In the cross-sectional view, the lines that appear in the cross section (due to cutting) are depicted, and the lines that exist behind the cross section are omitted. This also applies to the various embodiments described below.

[0067] The resin multilayer substrate 301 includes a multilayer substrate portion 101 and a mounting portion 201 .

[0068] The multilayer substrate 101 includes a plurality of resin layers 11, 12, 13, 14, and 15, and conductor layers and interlayer connection conductors attached to predetermined resin layers among the plurality of resin layers 11, 12, 13, 14, and 15. The conductor layers and interlayer connection conductors are conductors mainly composed of, for example, Cu or Ag.

[0069] The mounting portion 201 includes a resin layer 21 and a conductor layer 7 formed on the resin layer 21. Figure 1 In the figure, the resin layer 21 is shown as a single layer, but the resin layer 21 is composed of a single layer or a plurality of layers.

[0070] A connecting conductor BM is formed by coating in the openings of resin layer 15. Connecting conductor BM is, for example, a molten metal such as solder. A plurality of substrate-side pad electrodes 2a and 2b are formed below connecting conductor BM. In this example, resin layers 11, 12, 13, 14, and 15 are a laminate of thermoplastic resin sheets with Cu foil attached to one side.

[0071] A conductive layer 7 is formed on the upper surface of the mounting portion 201 or in the vicinity of the upper surface so that the mounting portion 201 functions as a circuit having predetermined electrical characteristics.

[0072] Terminal electrodes 6 a and 6 b are formed on the mounting surface (lower surface) of the mounting portion 201 . The terminal electrodes 6 a and 6 b are electrically connected to the pad electrodes 2 a and 2 b formed on the multilayer substrate portion 101 .

[0073] A plurality of external electrodes 1 are formed on the bottom surface of the multilayer substrate portion 101. These external electrodes 1 are connected to pad electrodes formed on another substrate, described later, thereby mounting the resin multilayer substrate 301 on the other substrate. Alternatively, as described later, electronic components can be mounted on these external electrodes 1 to form a resin multilayer substrate with mounted electronic components.

[0074] Signal line conductor patterns SL1 and SL2 and a ground conductor layer GL are formed within the multilayer substrate 101. These signal line conductor patterns SL1 and SL2, the ground conductor layer GL, and the resin layer between them form two microstrip transmission lines.

[0075] Mounting portion 201 is subjected to a temperature increase and decrease process before being mounted on multilayer substrate portion 101. As will be described later, this increases the elastic modulus by increasing the crystallinity of mounting portion 201. In other words, the elastic modulus of multilayer substrate portion 101 is relatively lower than that of mounting portion 201.

[0076] The elastic modulus was measured as follows. Using a TriboIndenter TI980 (Bruker Japan) as a measuring instrument, the elastic modulus of the crystalline thermoplastic resin (the first component) of the resin layers 11, 12, 13, 14, and 15 of the multilayer substrate 101 and the resin layer 21 of the mounting portion 201 was measured by nanoindentation. The measurement mode was (load-hold-unload): 5-2-5 seconds, load (indenter): 10 mN (Berkovich), and the number of measurement points: 5.

[0077] For example, when the crystalline thermoplastic resin is a liquid crystal polymer resin (LCP), the elastic modulus of the multilayer substrate portion 101 is 0.44 GPa lower than the elastic modulus of the mounting portion 201 .

[0078] like Figure 1 As shown, the mounting portion 201 is placed at a predetermined position on the multilayer substrate portion 101, and the entire portion is heated to a predetermined temperature and pressed at a predetermined pressure. This causes the connecting conductor BM to melt, thereby electrically connecting the pad electrodes 2a, 2b on the multilayer substrate portion to the terminal electrodes 6a, 6b on the mounting portion 201.

[0079] The resin layers 11, 12, 13, 14, and 15 of the multilayer substrate section 101 and the resin layer 21 of the mounting section 201 are all formed from a crystalline thermoplastic resin having the same first component. The heating and pressurizing described above allow the resin layers 11, 12, 13, 14, and 15 of the multilayer substrate section 101 to be directly bonded to the resin layer 21 of the mounting section 201. This allows for high adhesion between the mounting section 201 and the multilayer substrate section 101.

[0080] Thus, because the resin layers 11, 12, 13, 14, and 15 of the multilayer substrate section 101 and the resin layer 21 of the mounting section 201 are all made of the same crystalline thermoplastic resin, a higher degree of adhesion can be achieved between the mounting section 201 and the multilayer substrate section 101. Furthermore, because the resin layers of the multilayer substrate section 101 are made of a crystalline thermoplastic resin, the resin layers can be easily laminated at once, eliminating the need for a separate bonding step. This reduces the overall number of steps and enables low-cost manufacturing.

[0081] Here, the "first component" refers to, for example, a main component that excludes incidental layers, even if an adhesive layer is present to bond the resin layers together. For example, the resin layers 11, 12, 13, 14, and 15 of the multilayer substrate portion 101 and the resin layer 21 of the mounting portion 201 are all formed of a crystalline thermoplastic resin such as a wholly aromatic polyester resin or a thermoplastic polyimide resin.

[0082] The following relationship exists between the resin layers 11, 12, 13, 14, and 15 of the multilayer substrate section 101 and the resin layer 21 of the mounting section 201. Differential scanning calorimetry (DSC) was performed on the resin layers 11, 12, 13, 14, and 15 of the multilayer substrate section 101 and the resin layer 21 of the mounting section 201 at a temperature increase rate of 10°C / minute. In the first-up chart, a difference in the endothermic peak temperatures occurring at the initial temperature increase was observed, with the endothermic peak temperatures of the resin layers 11, 12, 13, 14, and 15 of the multilayer substrate section 101 being lower than the endothermic peak temperature of the resin layer 21 of the mounting section 201.

[0083] Figure 2 This is a typical example of a chart showing the temperature and DSC shift over time during differential scanning calorimetry (DSC). First, using a Rigaku DSC8230, the temperature was raised from room temperature at a rate of 10°C / minute to a temperature at which the crystalline thermoplastic resin completely melted. The temperature T1 of the first endothermic peak that appeared during this process was measured. However, broad, small peaks (area value: 0.8 mJ / mg or less) at the glass transition temperature were excluded. In other words, the temperature of such broad, small (shallow) peaks at the glass transition temperature was not considered as the endothermic peak temperature.

[0084] For example, if the resin layers 11 , 12 , 13 , 14 , 15 of the multilayer substrate portion 101 and the resin layer 21 of the mounting portion 201 are all liquid crystal polymer resin (LCP) having the same first component, the endothermic peak temperature T1 of the resin layers 11 , 12 , 13 , 14 , 15 of the multilayer substrate portion 101 is approximately 2.2°C lower than the endothermic peak temperature T1 of the resin layer 21 of the mounting portion 201 .

[0085] exist Figure 2In the 1st-up diagram, Tm1 is the first melting point. After the temperature rises above this first melting point, Tm1, the temperature is lowered below the endothermic peak temperature, T1, and then raised again. The melting point during this temperature rise (second melting point) is Tm2.

[0086] The above description states that "the resin layers 11, 12, 13, 14, 15 of the multilayer substrate portion 101 and the resin layer 21 of the mounting portion 201 are all layers formed of a crystalline thermoplastic resin having the same first component." The "same crystalline thermoplastic resin" is determined by the following method.

[0087] First, spectra of the crystalline thermoplastic resin used as the first component of both the mounting portion 201 and the multilayer substrate portion 101 were obtained using a Fourier transform infrared spectrophotometer (FT-IR). The spectra were then confirmed to have the same peaks and to be the same crystalline thermoplastic resin for both the mounting portion 201 and the multilayer substrate portion 101. Subsequently, the crystalline thermoplastic resin used as the first component was scraped off from each of the mounting portion 201 and the multilayer substrate portion 101, and samples were then subjected to differential scanning calorimetry (DSC) to measure the second melting point Tm2 of each component.

[0088] The method for determining the second melting point Tm2 is as follows. Figure 2 As shown, each crystalline thermoplastic resin was first heated at a rate of 10°C / min from room temperature to a temperature at which the crystalline thermoplastic resin was completely melted. The melted crystalline thermoplastic resin was then cooled at a rate of 10°C / min to room temperature and then heated at a rate of 10°C / min. During this heating process, the temperature of the endothermic peak at the temperature at which the crystalline thermoplastic resin was completely melted was defined as the second melting point Tm2 of the crystalline thermoplastic resin.

[0089] If the temperature difference between the second melting point Tm2 of the mounting portion 201 and the second melting point Tm2 of the multilayer substrate portion 101 is within 5° C., the crystalline thermoplastic resin of the mounting portion 201 and the crystalline thermoplastic resin of the multilayer substrate portion 101 are considered to be the same crystalline thermoplastic resin.

[0090] According to this embodiment, the following effects are achieved.

[0091] (a) When the resin layers 11, 12, 13, 14, 15 of the multi-layer substrate portion 101 and the resin layer 21 of the mounting portion 201 are made of different types of materials, it is difficult to ensure the close contact between the multi-layer substrate portion 101 and the mounting portion 201. However, since the resin layers 11, 12, 13, 14, 15 of the multi-layer substrate portion 101 and the resin layer 21 of the mounting portion 201 are layers formed of the same crystalline thermoplastic resin, it is easy to ensure the close contact between the two.

[0092] (b) Since the elastic modulus of the multilayer substrate portion 101 is lower than that of the mounting portion 201 , when the multilayer substrate portion 101 is bent while being heated to a temperature near its softening point, the mounting portion 201 is not deformed, and only the bendability of the multilayer substrate portion 101 can be improved.

[0093] Second Implementation Method

[0094] In the second embodiment, a resin multilayer substrate is exemplified in which the mounting structure of the mounting portion relative to the multilayer substrate portion is different from that of the first embodiment.

[0095] Figure 3 The lower part is a cross-sectional view of the resin multilayer substrate 302 according to the second embodiment. Figure 3 The upper portion is a cross-sectional view of the resin multilayer substrate 302 during the manufacturing process.

[0096] The resin multilayer substrate 302 includes a multilayer substrate portion 102 and a mounting portion 202 .

[0097] like Figure 3 As shown in the upper part of FIG, initially, the multi-layer substrate portion 102 and the mounting portion 202 are in an integrated laminated substrate state. Figure 3 Within the range shown in the upper part of , the left and right portions of the range shown by the dotted line are cut by a router by a predetermined amount, thereby forming a shape in which the mounting portion 202 is mounted on the multilayer substrate portion 102 .

[0098] Afterwards, through local heat treatment, the mounting portion 202 is heated and cooled while the multilayer substrate portion 101 is barely heated. The heating temperature of the mounting portion 202 is such that the endothermic peak temperature (T1) of the resin layer 21 of the mounting portion 202 is higher than the endothermic peak temperature (T1) of the resin layers 11, 12, 13, 14, and 15 of the multilayer substrate portion 101.

[0099] According to this embodiment, the step of mounting the mounting portion on the multi-layer substrate portion is unnecessary, and electrical connection and integrated bonding of resins are facilitated.

[0100] Third Implementation Method

[0101] In the third embodiment, a resin multilayer substrate having a mounting portion structure different from the examples shown in the first and second embodiments is exemplified.

[0102] Figure 4 The lower part is a cross-sectional view of a resin multilayer substrate 303 according to the third embodiment. Figure 4 The upper part is a top view of the mounting portion 203. Figure 4 The upper part, the single-dot chain line shows Figure 4However, the top view of the multi-layer substrate unit 101 is omitted.

[0103] The resin multilayer substrate 303 includes a multilayer substrate portion 101 and a mounting portion 203. The structure of the multilayer substrate portion 101 is similar to Figure 1 The multi-layer substrate portion 101 shown is the same.

[0104] A rectangular radiation electrode 7A is formed on or near the upper surface of the mounting portion 203. A ground electrode 7G is formed around the radiation electrode 7A. In other words, the mounting portion 203 functions as a patch antenna or as a part of a patch antenna.

[0105] The mounting portion 203 is a laminated structure comprising a resin layer 21 with Cu foil bonded to one side. Terminal electrodes 6A and 6G are formed on the mounting surface (lower surface) of the mounting portion 203. A laminated structure comprising multiple conductor foils 5 and multiple interlayer connecting conductors 4 is formed between the terminal electrode 6A and the radiation electrode 7A. Similarly, a laminated structure comprising multiple conductor foils 5 and multiple interlayer connecting conductors 4 is formed between the terminal electrode 6G and the ground electrode 7G. The interlayer connecting conductors 4 provide electrical continuity between the conductor layers formed of the conductor foils 5. In this manner, the laminated structure of the resin layers comprising the interlayer connecting conductors 4 and the conductor foils 5 in contact with the interlayer connecting conductors 4 forms a conductor path in the stacking direction within the mounting portion 203.

[0106] According to this embodiment, unlike a structure in which interlayer connections are formed by through-holes, a structure without openings (holes) can be realized, and the strength of the mounting portion 203 can be improved.

[0107] In this third embodiment, mounting portion 203 is also subjected to a temperature increase / decrease process before being mounted on multi-layer substrate portion 101. This increases the elastic modulus by increasing the crystallinity of mounting portion 203. In other words, the elastic modulus of multi-layer substrate portion 101 is relatively lower than that of mounting portion 203.

[0108] Fourth Implementation Method

[0109] In the fourth embodiment, a resin multilayer substrate is exemplified in which the structure of the interlayer connection conductor included in the mounting portion is different from the example shown in the third embodiment.

[0110] Figure 5 : is a cross-sectional view of a resin multilayer substrate 304 according to the fourth embodiment. The resin multilayer substrate 304 includes a multilayer substrate portion 101 and a mounting portion 204. The structure of the multilayer substrate portion 101 is similar to that of the Figure 1 The multi-layer substrate portion 101 shown is the same.

[0111] A rectangular radiation electrode 7A is formed on or near the upper surface of the mounting portion 204. A ground electrode 7G is formed around the radiation electrode 7A. Similar to the mounting portion 203 shown in the third embodiment, the mounting portion 204 functions as a patch antenna or as part of a patch antenna.

[0112] The mounting portion 204 is a laminated structure comprising a resin layer 21 with Cu foil bonded to one side. Terminal electrodes 6A and 6G are formed on the mounting surface (lower surface) of the mounting portion 204. A laminated structure comprising multiple conductor foils 5 and multiple interlayer connecting conductors 4 is formed between the terminal electrode 6A and the radiation electrode 7A. Similarly, a laminated structure comprising multiple conductor foils 5 and multiple interlayer connecting conductors 4 is formed between the terminal electrode 6G and the ground electrode 7G. The interlayer connecting conductors 4 are arranged at positions staggered in the X direction for adjacent layers. In this manner, a stacking-direction conductor path can be formed in the mounting portion 204, where the interlayer connecting conductors 4 are arranged at positions that do not overlap in the Z direction.

[0113] According to this embodiment, unlike a structure in which interlayer connections are made by through-holes, a structure without openings (holes) can be achieved, thereby improving the overall strength of mounting portion 204. Furthermore, unlike filled vias formed by plating through-holes, vias can be arranged at different positions within the inner layers of mounting portion 204, thereby increasing the degree of design freedom.

[0114] Fifth Implementation Method

[0115] In the fifth embodiment, a resin multilayer substrate is exemplified in which the structure of the interlayer connection conductor included in the mounting portion is different from the example shown in the fourth embodiment.

[0116] Figure 6 : is a cross-sectional view of a resin multilayer substrate 305 according to the fifth embodiment. The resin multilayer substrate 305 includes a multilayer substrate portion 105 and a mounting portion 205. The structure of the multilayer substrate portion 105 is similar to Figure 1 The multi-layer substrate 105 shown is similar to the above, but the resin layers 11, 12, 13, 14, and 15 are bonded together by adhesive layers shown by dotted lines.

[0117] A rectangular radiation electrode 7A is formed on or near the upper surface of the mounting portion 205. A ground electrode 7G is formed around the radiation electrode 7A. Similar to the mounting portion 203 shown in the third embodiment, the mounting portion 205 functions as a patch antenna or as part of a patch antenna.

[0118] The mounting portion 205 is a laminated structure composed of a resin layer 21 with Cu foil attached to one side, bonded together via an adhesive layer 20 (shown by a dotted line). Terminal electrodes 6A and 6G are formed on the mounting surface (lower surface) of the mounting portion 205. A laminated structure comprising multiple conductor foils 5 and multiple interlayer connecting conductors 4 is formed between the terminal electrode 6A and the radiation electrode 7A. Similarly, a laminated structure comprising multiple conductor foils 5 and multiple interlayer connecting conductors 4 is formed between the terminal electrode 6G and the ground electrode 7G. Interlayer connecting conductors 4 are arranged between the terminal electrode 6G and the ground electrode 7G, aligned in the Z direction. Interlayer connecting conductors 4 are arranged between the terminal electrode 6A and the radiation electrode 7A, staggered alternately in the X direction.

[0119] Furthermore, the radiation electrode 7A and the ground electrode 7G made of Cu foil are formed on the upper surface of the uppermost resin layer among the plurality of resin layers 21. In this way, the radiation electrode 7A and the ground electrode 7G may be exposed on the outer surface of the mounting portion 205.

[0120] Sixth Implementation Method

[0121] In the sixth embodiment, a resin multilayer substrate including electronic components is exemplified.

[0122] Figure 7 1 is a cross-sectional view of a resin multilayer substrate 306 according to the sixth embodiment. The resin multilayer substrate 306 includes a multilayer substrate portion 106, a mounting portion 203, and an electronic component 24. The electronic component 24 is not shown with hatching.

[0123] The multilayer substrate portion 106 includes a plurality of resin layers 11 , 12 , 13 , 14 , and 15 , and a conductor layer and an interlayer connection conductor attached to a predetermined resin layer among the plurality of resin layers.

[0124] The mounting portion 203 is the same as the mounting portion 203 shown in the third embodiment.

[0125] The component-side land electrode 42 is connected to the external electrode 1 of the multilayer substrate portion 106 via the connection conductor BM. The connection conductor BM is, for example, a heated molten metal such as solder.

[0126] The electronic component 24 is, for example, an IC that amplifies the power of a transmission signal and supplies it to an antenna, or an IC that amplifies a reception signal of the antenna.

[0127] According to the present embodiment, the electronic component 24 has high mountability on the multi-layer substrate portion 106 , and therefore the electronic component 24 can be easily mounted on the multi-layer substrate portion 106 .

[0128] Seventh Implementation Method

[0129] In the seventh embodiment, a resin multilayer substrate including a curved multilayer substrate portion is exemplified.

[0130] Figure 8 1 is a cross-sectional view of a resin multilayer substrate 307 according to the seventh embodiment. The resin multilayer substrate 307 includes a multilayer substrate portion 107 and a connector 25 mounted on the multilayer substrate portion 107. Hatching is omitted in the illustration of the connector 25.

[0131] The radiation electrode 7A is formed on the upper surface of the mounting portion 207 or in the vicinity of the upper surface, so that the mounting portion 207 functions as a patch antenna or as a part of the patch antenna.

[0132] Terminal electrodes 6 are formed on the mounting surface (lower surface) of mounting portion 207. A stack of multiple conductor foils 5 and multiple interlayer connection conductors 4 is formed between terminal electrodes 6 and radiation electrode 7A. In this manner, stacking resin layers including interlayer connection conductors 4 and conductor foils 5 in contact with these interlayer connection conductors 4 form a stacking-direction conductor path in mounting portion 207.

[0133] Signal line conductor patterns SLa, SLb and a ground conductor layer GL are formed inside the multilayer substrate 107. The signal line conductor patterns SLa, SLb, the ground conductor layer GL, and the resin layer therebetween form a microstrip transmission line.

[0134] A plurality of external electrodes 1 are exposed on the first surface S1 of the multilayer substrate portion 107. Pad electrodes 2 are formed on the second surface S2 of the multilayer substrate portion 107. Terminal electrodes 6 of the mounting portion 207 are bonded to the pad electrodes 2 via connecting conductors BM. Furthermore, the lower surface of the resin layer 21 at the bottom of the mounting portion 207 is bonded to the resin layer 15 of the multilayer substrate portion 107.

[0135] The component-side land electrode 42 is connected to the external electrode 1 of the multilayer substrate portion 107 via the connection conductor BM. The connection conductor BM is, for example, a heated molten metal such as solder.

[0136] exist Figure 8 In the example shown, the multilayer substrate portion 107 is bent (folded) by 90° along the XZ plane toward the mounting surface of the mounting portion 207. That is, the multilayer substrate portion 107 has a bent portion.

[0137] The connector 25 is connected to the patch antenna formed by mounting the mounting portion 207 .

[0138] According to the present embodiment, the multilayer substrate unit 107 having the bent portion formed by heating can be arranged in any space, and thus the resin multilayer substrate 307 having a predetermined shape as a whole can be configured.

[0139] Eighth Implementation Method

[0140] In the eighth embodiment, an example is shown in which the structure of the boundary portion between the multilayer substrate portion and the mounting portion is different from that of the resin multilayer substrate shown so far.

[0141] Figure 9 This is a cross-sectional view of a resin multilayer substrate 308 according to the eighth embodiment. The resin multilayer substrate 308 includes a multilayer substrate portion 108 and a mounting portion 208. The multilayer substrate portion 108 includes a plurality of resin layers 11, 12, 13, 14, and 15, as well as conductor layers and interlayer connection conductors attached to specific resin layers among these multiple resin layers. A connection conductor BM is formed by coating in the openings of the resin layer 15. The connection conductor BM is, for example, a heated molten metal such as solder. A multilayer substrate portion-side pad electrode 2 is formed below the connection conductor BM.

[0142] The radiation electrode 7A is formed on the upper surface of the mounting portion 208 or in the vicinity of the upper surface, so that the mounting portion 208 functions as a patch antenna or as a part of the patch antenna.

[0143] Inside the resin layer 21 , a filled plated through hole 9 is formed that is electrically connected to the radiation electrode 7A.

[0144] The boundary between the mounting portion 208 and the multilayer substrate portion 108 (the base of the mounting portion 208 ) is covered with resin material 10 . Since the resin material 10 covers the second surface S2 of the multilayer substrate portion 108 , the base of the mounting portion 208 is pressed into the multilayer substrate portion 108 .

[0145] The resin material 10 is, for example, epoxy resin, and is applied to the multilayer substrate 108 in a state where the mounting portion 208 is mounted thereon. The resin material 10 preferably has a Young's modulus higher than that of the resin layer constituting the multilayer substrate 108. The Young's modulus is determined by nanoindentation testing in accordance with JIS Z 2255 and ISO 14577. For example, the Young's modulus is determined from load-displacement data using a KLA Micro nanoindentation device.

[0146] The mounting portion of the mounting portion 208 is rigid, while the other portions are flexible. Therefore, when an external force tending to bend the resin multilayer substrate 308 is applied, stress tends to concentrate on the base of the mounting portion 208 .

[0147] In the resin multilayer substrate 308 of this embodiment, the bonding strength between the multilayer substrate portion 108 and the mounting portion 208 is high, thereby preventing cracks and chips at the interface between the multilayer substrate portion 108 and the mounting portion 208. Furthermore, the mounting portion 208 has high rigidity relative to the multilayer substrate portion 108, thereby suppressing deformation such as tilting of the mounting portion 208. This, in turn, prevents deviations in the antenna's radiation direction (directivity).

[0148] It should be noted that in Figure 9 , the resin material 10 is shown as a separate member from the multi-layer substrate unit 108 and the mounting portion 208. However, the shape of the resin material 10 may also be formed according to the multi-layer substrate unit 108 or the mounting portion 208. Specifically, after the mounting portion 208 is placed on the multi-layer substrate unit 108, pressure is applied to the multi-layer substrate unit 108 to press the mounting portion 208 into the mounting portion 208, and heat is applied to the multi-layer substrate unit 108. This causes the mounting portion 208 to sink into the multi-layer substrate unit 108, and the resin layer of the upper layer of the multi-layer substrate unit 108 is accumulated at the base of the mounting portion 208, forming the resin material 10 in this accumulated portion. Alternatively, the pressure and heat described above may be used to melt the base of the mounting portion 208, thereby forming the resin material 10.

[0149] Ninth Implementation Method

[0150] In the ninth embodiment, an electronic device including a resin multilayer substrate and another substrate is exemplified.

[0151] Figure 10 4 is a cross-sectional view of an electronic device 409 according to a ninth embodiment. The electronic device 409 includes another substrate 27, and a multilayer substrate portion 101 and a mounting portion 203 mounted on the other substrate 27. Hatching is omitted in the illustration of the other substrate 27.

[0152] The structure of the resin multilayer substrate 303 formed by the multilayer substrate portion 101 and the mounting portion 203 is similar to that in the third embodiment. Figure 4 The resin multilayer substrate 303 shown is the same.

[0153] The external electrodes 1 are formed on the mounting surface (lower surface) of the resin multilayer substrate 303 . The other substrate-side pad electrodes 41 are formed on the mounting surface (upper surface) of the other substrate 27 .

[0154] The external electrodes 1 of the multilayer substrate unit 101 are connected to other substrate-side pad electrodes 41 via connection conductors BM. The connection conductors BM are, for example, heated molten metal such as solder.

[0155] The other substrate 27 is, for example, a rigid glass epoxy substrate.

[0156] Tenth Implementation Method

[0157] In the tenth embodiment, an electronic device including a housing is exemplified.

[0158] An electronic device according to the present embodiment includes any of the resin multilayer substrates described in the first to ninth embodiments, and a housing that houses the resin multilayer substrate.

[0159] The housing for housing the resin multilayer substrate has a size and shape capable of housing (embedding) the resin multilayer substrate.

[0160] While various embodiments of the present invention have been described so far, they are all examples and are not intended to limit the scope of the present invention. The embodiments of the present invention may be omitted, replaced, or modified in various ways without departing from the gist of the invention. Embodiments in which such omissions, replacements, or modifications have been made are included within the scope of the present invention, the gist of the present invention, and are also included within the inventions described in the claims of this application and their equivalents.

[0161] For example, although the embodiments do not show examples in which a protective film is formed on the multi-layer substrate portion, the mounting portion, etc., a protective film may be formed on a predetermined portion or the entire surface of the outer surface.

[0162] In each embodiment, the signal line conductor pattern SL and the ground conductor layer GL are formed to configure a microstrip line. However, the structure of the resin multilayer substrate is not limited to a structure in which a transmission line is connected to the mounting portion.

[0163] The resin multilayer substrate and electronic device of the present invention can also be provided in the following aspects.

[0164] <1>

[0165] A resin multilayer substrate comprising:

[0166] a multilayer substrate portion including a plurality of resin layers and a conductor layer attached to a predetermined resin layer among the plurality of resin layers; and

[0167] a mounting portion having a resin layer and a conductor layer formed on the resin layer, and mounted on the multi-layer substrate portion or having a shape capable of being mounted on the multi-layer substrate portion;

[0168] The resin layer of the multi-layer substrate portion and the resin layer of the mounting portion are both layers formed of a crystalline thermoplastic resin having the same first component.

[0169] In a first-up chart of differential scanning calorimetry performed at a temperature increase rate of 10°C / min, there is a difference in endothermic peak temperatures appearing at the initial temperature increase for the resin layer of the multilayer substrate portion and the resin layer of the mounting portion, with the endothermic peak temperature of the resin layer of the multilayer substrate portion being lower than the endothermic peak temperature of the resin layer of the mounting portion.

[0170] The resin layer of the multi-layer substrate portion and the resin layer of the mounting portion are directly bonded to each other.

[0171] <2>

[0172] In the resin multilayer substrate described in <1>,

[0173] The crystalline thermoplastic resin is a wholly aromatic polyester resin.

[0174] <3>

[0175] In the resin multilayer substrate described in <1> or <2>,

[0176] The mounting portion is subjected to temperature increase and decrease treatments, thereby improving the crystallinity of the mounting portion compared to the multi-layer substrate portion.

[0177] <4>

[0178] In the resin multilayer substrate described in any one of <1> to <3>,

[0179] The elastic modulus of the multi-layer substrate portion is lower than the elastic modulus of the mounting portion.

[0180] <5>

[0181] In the resin multilayer substrate described in any one of <1> to <4>,

[0182] The mounting portion includes a plurality of resin layers, a conductor layer formed on the resin layer, and an interlayer connection conductor for electrically connecting the conductor layers.

[0183] <6>

[0184] In the resin multilayer substrate described in <5>,

[0185] The conductive layer formed on the mounting portion includes a radiation electrode and the interlayer connection conductor electrically connected to the radiation electrode.

[0186] <7>

[0187] In the resin multilayer substrate described in any one of <1> to <6>,

[0188] The multi-layer substrate portion has an interlayer connection conductor on the upper surface of the multi-layer substrate portion.

[0189] The mounting portion has terminal electrodes on the lower surface thereof,

[0190] The terminal electrodes of the mounting portion are electrically connected to the interlayer connection conductors of the multilayer substrate portion.

[0191] <8>

[0192] In the resin multilayer substrate described in any one of <1> to <7>,

[0193] A transmission line is formed on the multi-layer substrate portion.

[0194] <9>

[0195] In the resin multilayer substrate described in any one of <1> to <8>,

[0196] The multi-layer substrate portion has a bent portion.

[0197] <10>

[0198] In the resin multilayer substrate described in any one of <1> to <9>,

[0199] The multi-layer substrate portion includes external electrodes and a component connected to the external electrodes and mounted on the multi-layer substrate portion.

[0200] <11>

[0201] In the resin multilayer substrate described in any one of <1> to <10>,

[0202] A resin material is provided that covers a boundary between the mounting portion and the multi-layer substrate portion.

[0203] <12>

[0204] An electronic device comprising:

[0205] The resin multilayer substrate according to any one of <1> to <11>; and

[0206] Another substrate on which the resin multilayer substrate is mounted.

[0207] <13>

[0208] An electronic device comprising:

[0209] The resin multilayer substrate according to any one of <1> to <11>; and

[0210] A housing houses the resin multilayer substrate.

Claims

1. A resin multilayer substrate comprising: a multilayer substrate portion including a plurality of resin layers and a conductor layer attached to a predetermined resin layer among the plurality of resin layers; and a mounting portion having a resin layer and a conductor layer formed on the resin layer, and mounted on the multi-layer substrate portion or having a shape capable of being mounted on the multi-layer substrate portion; The resin layer of the multi-layer substrate portion and the resin layer of the mounting portion are both layers formed of a crystalline thermoplastic resin having the same first component. In a first-up chart of differential scanning calorimetry performed at a temperature increase rate of 10°C / min, there is a difference in endothermic peak temperatures appearing at the initial temperature increase for the resin layer of the multilayer substrate portion and the resin layer of the mounting portion, with the endothermic peak temperature of the resin layer of the multilayer substrate portion being lower than the endothermic peak temperature of the resin layer of the mounting portion. The resin layer of the multi-layer substrate portion and the resin layer of the mounting portion are directly bonded to each other.

2. The resin multilayer substrate according to claim 1, wherein The crystalline thermoplastic resin is a wholly aromatic polyester resin.

3. The resin multilayer substrate according to claim 1 or 2, wherein The mounting portion is subjected to temperature increase and decrease treatments, thereby improving the crystallinity of the mounting portion compared to the multi-layer substrate portion.

4. The resin multilayer substrate according to any one of claims 1 to 3, wherein The elastic modulus of the multi-layer substrate portion is lower than the elastic modulus of the mounting portion.

5. The resin multilayer substrate according to any one of claims 1 to 4, wherein The mounting portion includes a plurality of resin layers, a conductor layer formed on the resin layer, and an interlayer connection conductor for electrically connecting the conductor layers.

6. The resin multilayer substrate according to claim 5, wherein The conductive layer formed on the mounting portion includes a radiation electrode and the interlayer connection conductor electrically connected to the radiation electrode.

7. The resin multilayer substrate according to any one of claims 1 to 6, wherein The multi-layer substrate portion has an interlayer connection conductor on the upper surface of the multi-layer substrate portion. The mounting portion has terminal electrodes on the lower surface thereof, The terminal electrodes of the mounting portion are electrically connected to the interlayer connection conductors of the multilayer substrate portion.

8. The resin multilayer substrate according to any one of claims 1 to 7, wherein A transmission line is formed on the multi-layer substrate portion.

9. The resin multilayer substrate according to any one of claims 1 to 8, wherein The multi-layer substrate portion has a bent portion.

10. The resin multilayer substrate according to any one of claims 1 to 9, wherein The multi-layer substrate portion includes external electrodes and a component connected to the external electrodes and mounted on the multi-layer substrate portion.

11. The resin multilayer substrate according to any one of claims 1 to 10, wherein The resin multilayer substrate includes a resin material covering a boundary between the mounting portion and the multilayer substrate portion.

12. An electronic device comprising: The resin multilayer substrate according to any one of claims 1 to 11; and Another substrate on which the resin multilayer substrate is mounted.

13. An electronic device comprising: The resin multilayer substrate according to any one of claims 1 to 11; and A housing houses the resin multilayer substrate.

Images