Chip electronic component
11688555 · 2023-06-27
Assignee
Inventors
- Yukihiro Fujita (Nagaokakyo, JP)
- Shogo Kanbe (Nagaokakyo, JP)
- Kosuke Nakano (Nagaokakyo, JP)
- Hideki Otsuka (Nagaokakyo, JP)
Cpc classification
H01G4/232
ELECTRICITY
International classification
Abstract
A chip electronic component includes spacers that each have a predetermined thickness direction dimension on a mounting surface in a direction perpendicular to the mounting surface. The spacers each contain, as a main component, an intermetallic compound containing at least one high-melting-point metal selected from Cu and Ni, and Sn defining a low-melting-point metal.
Claims
1. A chip electronic component comprising: a chip component body including a mounting surface facing a mounting board; at least two outer electrodes disposed on outer surfaces of the component body; and at least two spacers respectively electrically connected to the at least two outer electrodes and at least partially disposed along the mounting surface of the component body; wherein each of the at least two spacers have a predetermined thickness direction dimension on the mounting surface in a direction perpendicular or substantially perpendicular to the mounting surface; each of the at least two spacers contains an intermetallic compound containing at least one metal selected from Cu and Ni, and a simple Sn metal; the chip component body has a rectangular or substantially rectangular parallelepiped shape including first and second main surfaces that oppose each other, first and second side surfaces that oppose each other, and first and second end surfaces that oppose each other, the first and second side surfaces and the first and second end surfaces connecting the first and second main surfaces, and the mounting surface is defined by the second main surface; the at least two outer electrodes are respectively provided on the first and second end surfaces and respectively extend from the first and second end surfaces to portions of the first and second main surfaces and portions of the first and second side surfaces; each of the at least two spacers is disposed on the second main surface and includes a portion in contact with a corresponding one of the at least two outer electrodes and a portion in contact with the second main surface; and the at least two spacers are bonded to the mounting board by a bonding material.
2. The chip electronic component according to claim 1, wherein the intermetallic compound is an intermetallic compound provided by a reaction between the Sn and a Cu—Ni alloy.
3. The chip electronic component according to claim 1, wherein the chip electronic component is a multilayer ceramic capacitor.
4. The chip electronic component according to claim 3, wherein the thickness direction dimension of each of the at least two spacers is about 10 μm or more.
5. The chip electronic component according to claim 1, wherein each of the at least two spacers contains a simple Sn metal, in addition to the intermetallic compound.
6. The chip electronic component according to claim 1, wherein outermost layers of at least portions of the at least two outer electrodes exposed from the at least two spacers are Sn-containing layers.
7. The chip electronic component according to claim 1, wherein edges and corners of the component body are filleted.
8. The chip electronic component according to claim 1, wherein the component body includes stacked ceramic layers and inner electrodes provided along interfaces between the ceramic layers.
9. The chip electronic component according to claim 8, wherein the inner electrodes contain Ni as a conductive component.
10. The chip electronic component according to claim 8, wherein each of the inner electrodes is connected to one of the at least two outer electrodes.
11. The chip electronic component according to claim 1, wherein each of the at least two spacers further contains Ag.
12. The chip electronic component according to claim 1, wherein an outermost layer of each of the at least two outer electrodes is an Sn plating layer.
13. The chip electronic component according to claim 1, wherein the component body has a longitudinal direction dimension of about 1.12 mm, a width direction dimension of about 0.63 mm, and a height direction dimension of about 0.63 mm.
14. A chip electronic component comprising: a chip component body including a mounting surface facing a mounting board; at least two outer electrodes disposed on outer surfaces of the component body; and at least two spacers respectively electrically connected to the at least two outer electrodes and at least partially disposed along the mounting surface of the component body; wherein each of the at least two spacers have a predetermined thickness direction dimension on the mounting surface in a direction perpendicular or substantially perpendicular to the mounting surface; each of the at least two spacers contains at least one metal selected from Cu and Ni, and a simple Sn metal; the chip component body has a rectangular or substantially rectangular parallelepiped shape including first and second main surfaces that oppose each other, first and second side surfaces that oppose each other, and first and second end surfaces that oppose each other, the first and second side surfaces and the first and second end surfaces connecting the first and second main surfaces, and the mounting surface is defined by the second main surface; the at least two outer electrodes are respectively provided on the first and second end surfaces and respectively extend from the first and second end surfaces to portions of the first and second main surfaces and portions of the first and second side surfaces; each of the at least two spacers is disposed on the second main surface and includes a portion in contact with a corresponding one of the at least two outer electrodes and a portion in contact with the second main surface; and the at least two spacers are bonded to the mounting board by a bonding material.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
(12) Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.
(13) Referring to
(14) The chip electronic component 1 includes a chip component body 3. The component body 3 preferably has, for example, a rectangular or substantially rectangular parallelepiped shape and includes first and second main surfaces 5 and 6, which oppose each other, first and second side surfaces 7 and 8, which oppose each other, and first and second end surfaces 9 and 10, which oppose each other. The first and second side surfaces 7 and 8 and the first and second end surfaces 9 and 10 connect the first and second main surfaces 5 and 6. In general, the edges and corners of the component body 3 having a rectangular or substantially rectangular parallelepiped shape are filleted.
(15) As illustrated in
(16) The inner electrodes 12 and 13 are disposed such that the edges of the inner electrodes 12 and 13 are each exposed on the end surface 9 or 10 of the component body 3. The first inner electrodes 12 exposed on the first end surface 9 of the component body 3 and the second inner electrodes 13 exposed on the second end surface 10 alternate in the component body 3 so as to obtain electrostatic capacitance through the ceramic layers 11.
(17) To obtain the electrostatic capacitance described above, a first outer electrode 14 electrically connected to the first inner electrode 12 and a second outer electrode 15 electrically connected to the second inner electrode 13 are respectively provided on the opposing first and second end surfaces 9 and 10 of the component body 3. The outer electrodes 14 and 15 are preferably formed by, for example, baking a conductive paste containing Cu as a conductive component. As needed, Ni plating and Sn plating are performed on the outer electrodes 14 and 15 in this order.
(18) The first outer electrode 14 is not only provided on the first end surface 9 of the component body 3 but also extends to portions of the first and second main surfaces 5 and 6 and portions of the first and second side surfaces 7 and 8, which are adjacent to the end surface 9. The second outer electrode 15 is not only provided on the second end surface 10 of the component body 3 but also extends to portions of the first and second main surfaces 5 and 6 and portions of the first and second side surfaces 7 and 8, which are adjacent to the end surfaces 10.
(19) In the chip electronic component 1, as illustrated in
(20) The first and second spacers 16 and 17 are disposed along the mounting surface 6. In the present preferred embodiment, the spacers 16 and 17 are disposed within the mounting surface 6, but the spacers 16 and 17 may extend to other surfaces of the component body 3.
(21) The spacers 16 and 17 preferably each contain, for example, as a main component, an intermetallic compound containing at least one high-melting-point metal selected from Cu and Ni, and Sn defining a low-melting-point metal. In particular, the intermetallic compound is preferably, for example, an intermetallic compound provided by the reaction between Sn and a Cu-Ni alloy. Such an intermetallic compound has advantages of high reaction rate and small shape change when the intermetallic compound is provided. The spacers 16 and 17 may further contain Ag as a high-melting-point metal in the intermetallic compound.
(22) As illustrate in
(23) As illustrated in
(24) The spacers 16 and 17 preferably contain, for example, a simple Sn metal, in addition to the intermetallic compound. The Sn metal in the spacers 16 and 17 provides good solderability when the chip electronic component 1 is mounted on the mounting board 2. To obtain the spacers 16 and 17 containing a simple Sn metal, for example, excess Sn is added to a metal material of the intermetallic compound. A portion of excess Sn is not used to provide the intermetallic compound and remains as a simple Sn metal in the spacers 16 and 17.
(25) To provide good solderability, Sn plating may be performed over the spacers 16 and 17 and portions of the outer electrodes 14 and 15 exposed from the spacers 16 and 17 after the spacers 16 and 17 are provided.
(26) When Ni plating and Sn plating are sequentially performed on the outer electrodes 14 and 15 as described above, the outermost layers of the outer electrodes 14 and 15 are Sn-containing layers at least in the stage before the spacers 16 and 17 are provided. In this case, a portion of the spacer 16 and a portion of the spacer 17 come into contact with the Sn-containing layers when the spacers 16 and 17 are provided. The Sn in the Sn-containing layers contributes to favorable formation of the intermetallic compound in the spacers 16 and 17. Therefore, the Sn in the outermost layers of the outer electrodes 14 and 15 remains in the regions exposed from the spacers 16 and 17 even after formation of the spacers 16 and 17. In the regions in contact with the spacers 16 and 17, the Sn may not remain after formation of the spacers 16 and 17.
(27) In the mounted state of the chip electronic component 1, the solders 20 may extend to or may not extend to the outer electrodes 14 and 15 over the spacers 16 and 17, as illustrated in
(28) In order that the solders 20 do not extend to the outer electrodes 14 and 15 as described above, it is preferable that Sn-containing layers with high wettability to the solders 20 are not provided on the outermost layers of portions of the outer electrodes 14 and 15 exposed from the spacers 16 and 17. This indicates that the outer electrodes 14 and 15 may be subjected to only Ni plating without Sn plating or may be Cu-baked electrodes.
(29) Next, a non-limiting example of a preferred method for forming the spacers 16 and 17 will be described.
(30) (1) The component body 3 including the outer electrodes 14 and 15 is prepared.
(31) (2) A metal material paste containing at least one high-melting-point metal selected from Cu and Ni, and Sn defining and functioning as a low-melting-point metal is prepared as a material of the spacers 16 and 17.
(32) (3) A holder plate, such as alumina plate, for example, to which the metal material paste is not bonded under the reflow conditions is prepared.
(33) (4) Metal material paste thick films are formed by applying the metal material paste in a desired pattern to the holder plate by, for example, a screen printing method or a dispensing method.
(34) (5) The component body 3 prepared in (1) is mounted on the holder plate such that the mounting surface 6 opposes the holder plate. At this time, the outer electrodes 14 and 15 of the component body 3 are aligned with the metal material paste thick films made of the metal material paste, and the metal material paste thick films adhere to the component body 3 so as to cover a portion of the outer electrode 14 and a portion of the outer electrode 15.
(35) (6) The reflow process is performed in the state of (5). In this process, the metals in the metal material paste form an intermetallic compound, and the metal material paste is solidified to form the spacers 16 and 17 bonded to the component body 3 and the outer electrodes 14 and 15.
(36) (7) The component body 3 is isolated from the holder plate together with the spacers 16 and 17.
(37) The chip electronic component 1 including the spacers 16 and 17 is obtained accordingly.
(38) Next, referring to
(39) In the chip electronic component 21, the thickness direction dimension T of the spacers 16 and 17 is larger than that in the chip electronic component 1. With this configuration, a different electronic component 22 is able to be mounted between the chip electronic component 21 and the mounting board 2. The different electronic component 22 is preferably, for example, a chip electronic component, and outer electrodes 23 and 24 of the electronic component 22 are electrically connected and mechanically bonded to conductive lands 25 and 26 on the mounting board 2 respectively with solders 27 interposed therebetween.
(40) The three-dimensional mounting as described above is able to reduce the area used for mounting.
(41) Next, an Experimental Example 1 provided to confirm the advantageous effects of reducing the “acoustic noise” generated by the chip electronic component 1, which defines a multilayer ceramic capacitor, according to the first preferred embodiment will be described.
(42)
(43) Referring to
(44) The sound pressure level of the unpleasant sound obtained as described above is shown in Table 1 and
(45) TABLE-US-00001 TABLE 1 Spacer Sound Pressure Sample No. Thickness [mm] Level [OA] 1 0 73.7 2 0.016 69.6 3 0.017 68.6 4 0.025 67.3 5 0.031 66.7 6 0.033 68.2 7 0.038 67.4 8 0.076 65.6 9 0.089 63.9 10 0.091 61.2 11 0.093 64.4 12 0.109 63.4
(46) Table 1 and
(47) In an Experimental Example 2, the configuration retainability after reflow was compared between an Example according to a preferred embodiment of the present invention and a Comparative Example. In the Example, a metal material containing, as a main component, an intermetallic compound containing at least one high-melting-point metal selected from Cu and Ni, and Sn defining and functioning as a low-melting-point metal was used as a metal material for the spacers. In the Comparative Example, the lead-free solder with a composition of Sn—Ag—Cu described in International Publication No. 2015/098990 was used as a metal material for the spacers.
(48) In the Example, the metal material paste containing about 31.5 wt % of a Cu—about 10 wt % Ni powder with a D50 of about 5 μm, about 58.5 wt % of a solder powder with a D50 of about 5 μm, and a composition of Sn-3 wt % Ag-0.5 wt % Cu, and about 10 wt % of a flux was used as in the Experimental Example 1.
(49) In the Comparative Example, a lead-free solder paste “M705-GRN360-K2-V” with a composition of Sn-Ag-Cu available from Senju Metal Industry Co., Ltd. was used as a metal material paste.
(50) The chip electronic component 41 as illustrated in
(51) Next, the metal material paste was applied to portions of the outer electrodes 43 and 44 adjacent to a mounting surface 45 of the component body 42 to form metal material paste thick films 46, which would define and function as spacers having a rectangular pattern as illustrated in
(52) Sample 1: The metal material paste thick films 46 were formed on the chip electronic component 41A using the metal material paste according to the Example as a metal material paste.
(53) Sample 2: The metal material paste thick films 46 were formed on the chip electronic component 41B using the metal material paste according to the Example as a metal material paste.
(54) Sample 3: The metal material paste thick films 46 were formed on the chip electronic component 41C using the metal material paste according to the Example as a metal material paste.
(55) Sample 4: The metal material paste thick films 46 were formed on the chip electronic component 41A using the metal material paste according to the Comparative Example as a metal material paste.
(56) Sample 5: The metal material paste thick films 46 were formed on the chip electronic component 41B using the metal material paste according to the Comparative Example as a metal material paste.
(57) Sample 6: The metal material paste thick films 46 were formed on the chip electronic component 41C using the metal material paste according to the Comparative Example as a metal material paste.
(58) Next, the metal material paste thick films 46 of Samples 1 to 6 were subjected to a reflow treatment. The configuration of the metal material thick films which would define and function as spacers obtained after the reflow treatment of the metal material paste thick films 46 was then evaluated.
(59) In any of Samples 1 to 3 according to the Example, as illustrated in
(60) In Sample 4 according to the Comparative Example, as illustrated in
(61) Next, in Sample 5 according to the Comparative Example, as illustrated in
(62) Next, in Sample 6 according to the Comparative Example, as illustrated in
(63) When the metal material thick films 47 according to the Example and the metal material thick films 47 according to the Comparative Example were heated until the reflow temperature was reached again, the metal material thick films 47 according to the Example were confirmed to maintain their configurations in any of Samples 1 to 3. In Sample 4, the metal material thick films 47 according to the Comparative Example became molten again other than small portions of the metal material thick films 47 in contact with the Sn plating films on the surfaces of the outer electrodes 43 and 44. In Samples 5 and 6, the metal material thick films 47 according to the Comparative Example entirely became molten again.
(64) Additionally, as illustrated in
(65) In the case of using the metal material paste according to the Example, the spacers 16 and 17 made of the metal material thick films in an appropriate configuration were formed regardless of the presence or absence of the Sn plating films on the surfaces of the outer electrodes 14 and 15.
(66) In the case of using the metal material paste according to the Comparative Example, the spacers 16 and 17 in an appropriate configuration were not formed. In particular, when the Sn plating films were present on the surfaces of the outer electrodes 14 and 15, a large portion of the metal material located on the mounting surface 6 was attracted to the outer electrodes 14 and 15 as a result of the reflow process, which resulted in a failure to form the spacers so as to include portions in contact with the first and second outer electrodes 14 and 15 and portions in contact with the mounting surface 6.
(67) In the foregoing description, a chip electronic component that defines a multilayer ceramic capacitor is described as the chip electronic component according to preferred embodiments of the present invention. Preferred embodiments of the present invention may also be applied to chip electronic components having electrostriction, such as chip coil components and chip piezoelectric components, for example, other than multilayer ceramic capacitors.
(68) Since the spacers which are characteristic structures of preferred embodiments of the present invention not only reduce the “acoustic noise” but also to enable three-dimensional mounting, chip electronic components according to preferred embodiments of the present invention are not limited to those having electrostriction.
(69) It should be understood that the preferred embodiments described above are illustrative only, and partial replacements or combinations of configurations may be made between different preferred embodiments.
(70) While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims.