JP2013045891A - Electronic component and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component which efficiently achieves the thickness reduction of an external electrode and the improvement of the adhesion strength.SOLUTION: An external electrode E1 of an electronic component is composed of: metal particles SP1 adhered to a surface of an external electrode formation part CBa of a component body CB in a scattered state; and an electrode main film Fsp2 formed on the surface of the external electrode formation part CBa of the component body CB so as to cover the metal particles SP1.

Description

  The present invention relates to an electronic component in which an external electrode is devised, and a method for manufacturing an electronic component having the external electrode.

  Electronic components such as chip capacitors, chip inductors, chip resistors, and piezoelectric chips have functional elements provided inside the component body, such as external electrodes that are electrically connected to an electrode layer, a coil, a resistance layer, etc. Is provided on the surface.

  This external electrode is generally composed of an electrode base film formed on a part of the surface of the component body and an electrode main film formed on the surface of the electrode base film. As a method, application and baking of a metal paste are adopted, and electrolytic plating is adopted as a method of forming the electrode main film. The electrode base film constituting the external electrode serves to improve the adhesion strength of the electrode main film. However, since the electrode base film is formed by applying and baking a metal paste, the thickness of the external electrode For example, it is extremely difficult to reduce the thickness of the external electrode to the order of μm.

  The thickness of the external electrode has a greater influence on the size of the electronic component as the electronic component becomes smaller (for example, 0603 size or 0402 size). Therefore, reduction of the thickness of the external electrode has been regarded as important, and an attempt has been made to form both an electrode base film and an electrode main film constituting the external electrode by a sputtering method in order to reduce the thickness ( (See Patent Document 1).

  However, the external electrode disclosed in Patent Document 1 is composed of an electrode base film for improving adhesion strength and an electrode main film as in the case of the previous external electrode, and “thickness of external electrode = thickness of electrode base film”. + Electrode main film thickness ”, reducing the thickness of both the electrode base film and electrode main film may reduce the adhesion strength of the external electrode if only the electrode main film thickness is reduced. Without it, the thickness of the external electrode cannot be reduced. In short, the external electrode structure disclosed in Patent Document 1 has a limit in satisfying both the thickness reduction of the external electrode and the improvement of the adhesion strength.

  The inventor of the present application has intensively researched in view of the above circumstances, and by developing an external electrode structure having no electrode base film, an electronic component that can effectively reduce the thickness of the external electrode and improve the adhesion strength, and the external It came to create the manufacturing method suitable for preparation of the electronic component which has an electrode.

JP 2000-299514 A

  An object of the present invention is to provide an electronic component capable of effectively reducing the thickness of an external electrode and improving adhesion strength, and a manufacturing method suitable for manufacturing an electronic component having the external electrode.

  In order to achieve the above object, the present invention (electronic component) is an electronic component having an external electrode on the surface of the component main body, and the external electrode adheres to the surface of the external electrode forming portion of the component main body in a scattered state. And a main electrode film formed on the surface of the external electrode forming portion of the component main body so as to cover the metal particles.

  Moreover, this invention (manufacturing method of an electronic component) is a manufacturing method of the electronic component provided with the process of forming an external electrode in the surface of a component main body, Comprising: The said external electrode formation process is (1) said sputtering method by said sputtering method (2) forming a main electrode film so as to cover the metal particles on the surface of the external electrode forming portion of the component main body by a sputtering method; Including the step of performing.

  According to the electronic component and the manufacturing method thereof according to the present invention, the following effects can be obtained. That is, since the metal particles adhere to the surface of the external electrode forming portion of the component body in a scattered state, the locations where the metal particles are present on the surface of the external electrode forming portion are convex and nonexistent locations (external The portion where the surface of the electrode forming portion is exposed becomes concave. In addition, since the electrode main film is formed on the surface of the external electrode forming portion so as to cover the metal particles adhering in the scattering state, the electrode main film reaches the surface of the external electrode forming portion by entering the recess. Thick portions and thin portions that do not enter the recesses are mixed.

  In other words, the electrode main film has an effect of increasing the total adhesion area as compared with the case where the electrode main film is directly formed on a flat surface, and an anchor action based on the shape of the metal particles is obtained. The adhesion strength of the electrode main film can be improved. In addition, since the adhesion strength can be improved even if the maximum thickness of the electrode main film corresponding to the thickness of the external electrode is set to the minimum value that can cover the metal particles, the maximum thickness of the electrode main film is reduced. Therefore, the thickness of the external electrode can be reduced.

  In short, the electronic component according to the present invention can effectively reduce the thickness of the external electrode and improve the adhesion strength by adopting the external electrode structure having no electrode base film. According to the method for manufacturing an electronic component according to the above, it is possible to accurately manufacture an electronic component that can obtain the above-described effect.

  The above object and other objects, structural features, and operational effects of the present invention will become apparent from the following description and the accompanying drawings.

FIG. 1 is an explanatory diagram of a first step of external electrode formation according to the first embodiment. FIG. 2 is a side view of the component main body after the first step. FIG. 3 is an explanatory diagram of a second step of external electrode formation according to the first embodiment. FIG. 4 is a side view of the component main body after the second step. FIG. 5 is a side view of the electronic component after forming the external electrodes. FIG. 6 is a diagram showing the adhesion strength between the external electrodes of the verified product and the comparative product. FIG. 7 is an explanatory diagram of a method for measuring the adhesion strength shown in FIG. FIG. 8 is a side view of a comparative product. FIG. 9 is an explanatory diagram of a first step of external electrode formation according to the second embodiment. FIG. 10 is a side view of the component main body after the first step. FIG. 11 is an explanatory diagram of a second step of external electrode formation according to the second embodiment. FIG. 12 is a side view of the component main body after the second step. FIG. 13 is a side view of the electronic component after forming the external electrode. FIG. 14 is a diagram illustrating the adhesion strength between the external electrodes of the verified product and the comparative product. FIG. 15 is a side view of a comparative product.

<< First Embodiment >>
FIG. 1 shows a DC magnetron type sputtering apparatus 10 used for forming an external electrode. The sputtering apparatus 10 includes a chamber 11, an upper target electrode 12, a magnet 13 having N and S poles, and a lower sample. A base electrode 14 and a DC power source 15 are provided. The chamber 11 has a first port 11a connected to a gas supply source (not shown) and a second port 11b connected to a vacuum pump (not shown). The upper target electrode 12 has a flat lower surface, and the magnet 13 is provided on the lower surface or inside thereof. The magnet 13 is composed of a permanent magnet or an electromagnet. In the case of a permanent magnet, a magnetic field can always be formed. In the case of an electromagnet, the formation and non-formation of a magnetic field can be selected as appropriate by supplying or not supplying power. The lower sample stage electrode 14 has a flat upper surface, and the upper surface faces the lower surface of the upper target electrode 12 in parallel. The DC power source 15 supplies predetermined DC power to the upper target electrode 12 and the lower sample stage electrode 14. The DC power source 15 has a function of switching the connection polarity between the upper target electrode 12 and the lower sample stage electrode 14.

<First step of external electrode formation>
In performing the first step, as shown in FIG. 1, the target TA1 is disposed on the lower surface of the upper target electrode 12, and the component holder J1 holding a large number of component bodies CB is disposed on the lower sample stage electrode 14. Place on the top surface.

  The target TA1 has a flat plate shape having a predetermined thickness. The material of the target TA1 is preferably iron or an alloy mainly composed of iron such as stainless steel. Of course, titanium, chromium, tantalum, an alloy containing at least one of these, or the like may be used as the material of the target TA1.

  The component holder J1 has a flat plate shape having a predetermined thickness, and has a large number of recesses J1a on the upper surface thereof. Each recess J1a is for housing and holding a portion excluding a part of the component main body CB (external electrode forming portion CBa), and the surface of the external electrode forming portion CBa is exposed from the component holder J1 (FIG. 2). The material of the component holder J1 may be either a conductive material or a non-conductive material, but stainless steel or aluminum is preferable when the component holder J1 functions as an electrode.

  The component body CB becomes an electronic component such as a chip capacitor, a chip inductor, a chip resistor, or a piezoelectric chip by forming external electrodes, and has a substantially rectangular parallelepiped shape. The component main body CB is mainly made of ceramics and has functional elements such as an electrode layer, a coil, a resistance layer, and the like. The ceramic material that is the main material of the component body CB varies depending on the electronic component, but representative examples include barium titanate, strontium titanate, titanium oxide, aluminum oxide, and lead zirconate titanate.

Then, an inert gas is introduced from the gas supply source into the chamber 11 through the first port 11a, and the vacuum level in the chamber 11 is adjusted through the second port 11b by a vacuum pump. A high DC voltage is applied to the electrodes 12 and 14 for a predetermined time from a DC power source 15 with the target electrode 12 as a negative electrode and the lower sample stage electrode 14 as a positive electrode.

The inert gas introduced into the chamber 11 is preferably argon, but may be neon, xenon, or the like. Moreover, although it changes with the specifications of the sputtering apparatus 10, the inert gas introduction amount into the chamber 11 is set to a value within the range of 10 to 500 sccm, and the degree of vacuum within the chamber 11 is approximately within the range of 10 ^{−1 to} 50 Pa. The high DC voltage applied to both electrodes 12 and 14 is set to a value in the range of approximately 10 to 10000 W when expressed as power, and the application time of the high DC voltage is approximately in the range of 10 to 60 sec. Is set to the value of

  As a result, as shown in FIGS. 1 and 2, the inert gas is turned into plasma, and positive ions II collide with the target TA1, and metal particles (pointing to atoms and molecules) SP1 fly off from the surface of the target TA1. Then, the repelled metal particles SP1 adhere to the surface of the external electrode forming portion CBa of each component body CB in a scattered state.

  The important point in this first step is to attach the metal particles SP1 in a scattered state to the surface of the external electrode forming portion CBa of the component main body CB. The particle size of the metal particles SP1 blown off from the surface of the target TA1 is on the order of nm. However, if the application time of the high DC voltage is lengthened, the metal particles SP1 are deposited on the surface of the external electrode forming portion CBa of the component body CB. Here, the formation of the film is avoided by shortening the application time of the high DC voltage as much as possible. Incidentally, when the surface coverage of the metal particles SP1 attached to the surface of the external electrode forming portion CBa of the component main body CB is represented by a numerical value, it is in the range of 30 to 90%.

<Second step of external electrode formation>
When performing the second step following the first step, as shown in FIG. 2, the target TA1 is replaced with another target TA2.

  The target TA2 has a flat plate shape with a predetermined thickness. The material of the target TA2 is a material that becomes an electrode main film of the external electrode, and is preferably copper, nickel, silver, or the like.

  Then, an inert gas is introduced from the gas supply source into the chamber 11 through the first port 11a, and the vacuum level in the chamber 11 is adjusted through the second port 11b by a vacuum pump. A high DC voltage is applied to the electrodes 12 and 14 for a predetermined time from a DC power source 15 with the target electrode 12 as a negative electrode and the lower sample stage electrode 14 as a positive electrode.

The inert gas introduced into the chamber 11 is preferably argon, but may be neon, xenon, or the like. Moreover, although it changes with the specifications of the sputtering apparatus 10, the inert gas introduction amount into the chamber 11 is set to a value within the range of 10 to 500 sccm, and the degree of vacuum within the chamber 11 is approximately within the range of 10 ^{−1 to} 50 Pa. The high DC voltage applied to both electrodes 12 and 14 is set to a value in the range of approximately 10 to 10000 W when expressed as power, and the application time of the high DC voltage is approximately in the range of 60 to 300 sec. Is set to the value of

  As a result, as shown in FIGS. 3 and 4, the inert gas is turned into plasma, and positive ions II collide with the target TA2, and metal particles (pointing to atoms and molecules) SP2 fly off from the surface of the target TA2. Then, the bounced metal particles SP2 are deposited on the surface of the external electrode forming portion CBa of each component body CB so as to cover the metal particles SP1 to form the electrode main film Fsp2.

  The important point in the second step is to form the electrode main film Fsp2 by depositing the metal particles SP2 on the surface of the external electrode forming portion CBa of the component main body CB so as to cover the metal particles SP1. Here, the electrode main film Fsp2 covering the metal particles SP1 is formed by setting the application time of the high DC voltage to a time suitable for film formation. Incidentally, when the maximum thickness of the electrode main film Fsp2 is expressed by a numerical value, it is a value within a range of 0.5 to 10 μm, preferably 1 to 3 μm.

<Third step of external electrode formation>
When performing the third step subsequent to the second step, the target TA2 is replaced with the target TA1, and the direction of each component body CB held by the component holder J1 is reversed and held again. The holder J1 is disposed on the upper surface of the lower sample stage electrode 14.

  Then, under the same conditions as in the first step, an inert gas was introduced from the gas supply source into the chamber 11 through the first port 11a, and the degree of vacuum in the chamber 11 was adjusted through the second port 11b by a vacuum pump. In this state, under magnetic field formation, a high DC voltage is applied to both electrodes 12 and 14 for a predetermined time from the DC power source 15 with the upper target electrode 12 as a negative electrode and the lower sample stage electrode 14 as a positive electrode.

  As a result, as in the first step, the inert gas is turned into plasma, the positive ions II collide with the target TA1, and metal particles (pointing to atoms and molecules) SP1 are blown off from the surface of the target TA1. The metal particles SP1 thus adhered adhere to the surface of the external electrode forming portion CBa on the opposite side of each component body CB in a scattered state. The important points in the third step are as described in the first step.

<Fourth step of external electrode formation>
When performing the fourth step following the third step, the target TA1 is replaced with the target TA2.

  Then, under the same conditions as in the second step, an inert gas was introduced from the gas supply source into the chamber 11 through the first port 11a, and the degree of vacuum in the chamber 11 was adjusted through the second port 11b by a vacuum pump. In this state, under magnetic field formation, a high DC voltage is applied to both electrodes 12 and 14 for a predetermined time from the DC power source 15 with the upper target electrode 12 as a negative electrode and the lower sample stage electrode 14 as a positive electrode.

  As a result, as in the second step, the inert gas is turned into plasma, the positive ions II collide with the target TA2, and the metal particles (pointing to atoms and molecules) SP2 are blown off from the surface of the target TA2. The deposited metal particles SP2 are deposited on the surface of the external electrode forming portion CBa on the opposite side of each component body CB so as to cover the metal particles SP1, thereby forming the electrode main film Fsp2. The important points in the fourth step are as described in the second step.

<Electronic components with external electrodes on the component body>
FIG. 5 shows an electronic component such as a chip capacitor, a chip inductor, a chip register, or a piezoelectric chip in which external electrodes E1 are formed on both ends of the component main body CB through the first to fourth steps. The external electrode E1 here is the metal particles SP1 adhering to the surface of the external electrode forming portion CBa of the component main body CB in a scattered state, and the electrode formed to cover the metal particles SP1 on the surface of the external electrode forming portion CBa. It consists of a main membrane Fsp2.

<Effects obtained by electronic parts and manufacturing method thereof>
As can be seen from FIG. 2, since the metal particles SP1 adhere to the surface of the external electrode forming portion CBa of the component body CB in a scattered state, there are places where the metal particles SP1 exist on the surface of the external electrode forming portion CBa. A portion that is convex and does not exist (a portion where the surface of the external electrode forming portion CBa is exposed) is concave. Further, as can be seen from FIG. 4, the electrode main film Fsp2 is formed on the surface of the external electrode formation portion CBa so as to cover the metal particles SP1 adhering in a scattered state, and thus the electrode main film Fsp2 has the concave portion. A maximum thickness portion that enters and reaches the surface of the external electrode forming portion CBa and a thin portion that does not enter the recess are mixed.

  That is, the electrode main film Fsp2 has an effect of increasing the total contact area as compared with the case where the electrode main film Fsp2 is directly formed on a flat surface (see FIG. 8), and the shape of the metal particle SP1. Therefore, the adhesion strength of the electrode main film Fsp2 can be improved. Further, since the adhesion strength can be improved even if the maximum thickness of the electrode main film Fsp2 corresponding to the thickness of the external electrode E1 is set to the minimum value that covers the metal particles SP1, the maximum thickness of the electrode main film Fsp2 can be increased. The thickness of the external electrode E1 can be reduced by reducing the thickness.

  In short, according to the electronic component, by adopting the external electrode structure having no electrode base film, it is possible to effectively reduce the thickness of the external electrode E1 and improve the adhesion strength. According to this, an electronic component capable of obtaining the above-described effect can be accurately manufactured.

<Verification of effect>
When verifying the above-mentioned effects, particularly the improvement in adhesion strength, five verification products 1-1 to 1-3 (see FIG. 5) and comparative products (see FIG. 8) were prepared, and an adhesion strength test was performed on each. To confirm the result.

The verified products 1-1 to 1-3 are obtained by forming an external electrode E1 on a component main body of a 0603 size chip capacitor (mainly composed of barium titanate) as the component main body CB. E1
[Verification product 1-1]
(Conditions for the first step and the third step)
・ Inert gas: Argon ・ Introducing amount of inert gas: 10 sccm
・ Vacuum degree of chamber 11: 0.5 Pa
・ DC power: 100W
-DC power application time: 60 sec
-Target TA1: Surface coverage of iron / metal particles SP1: 50%
(Conditions for the second step and the fourth step)
・ Inert gas: Argon ・ Introducing amount of inert gas: 100 sccm
・ Vacuum degree of chamber 11: 3 Pa
・ DC power: 100W
-DC power application time: 180 sec
・ Target TA2: Copper ・ Maximum thickness of electrode main film Fsp2: 1 μm
[Verification product 1-2]
(Conditions for the first step and the third step)
・ Inert gas: Argon ・ Introducing amount of inert gas: 100 sccm
・ Vacuum degree of the chamber 11: 2 Pa
・ DC power: 100W
-DC power application time: 15 sec
Target TA1: Surface coverage of iron / metal particle SP1: 70%
(Conditions for the second step and the fourth step)
Same as verification product 1-1 [Verification product 1-3]
(Conditions for the first step and the third step)
・ Inert gas: Argon ・ Introducing amount of inert gas: 500 sccm
・ Vacuum degree of chamber 11: 30 Pa
・ DC power: 100W
-DC power application time: 10 sec
Target TA1: Surface coverage of iron / metal particles SP1: 40%
(Conditions for the second step and the fourth step)
It was formed according to the first to fourth steps in the same manner as the verification product 1-1.

On the other hand, the comparative product is formed by forming an external electrode E1 'on a component body of a 0603 size chip capacitor (mainly composed of barium titanate) as the component body CB, and the external electrode E1'
[Comparative product]
(Conditions for the first step and the third step)
The first step and the third step are not performed (conditions of the second step and the fourth step)
It was formed according to the second step and the fourth step in the same manner as the verification product 1-1. As can be seen from FIG. 8, the comparative external electrode E1 ′ is a metal particle SP1 adhering to the surface of the external electrode forming portion CBa in a scattered state, such as verification products 1-1 to 1-3 (see FIG. 5). ”And only the electrode main film Fsp2.

As shown in FIG. 7, in the adhesion strength test, a lead-free solder paste is applied to the copper pad SUBa of the glass epoxy substrate SUB with a thickness of 50 μm by screen printing, and a verification product 1-1 to 1-3 is applied thereon. And comparative products are mounted, reflow soldering is performed at a peak temperature of 280 ° C. and a temperature profile of 10 seconds, and the center of the side of the verification products 1-1 to 1-3 and the comparison products (with a load cell type pressure tester) The pressure was applied at a speed of 2.5 mm / min, and the load when each external electrode E1 was peeled was converted into adhesion strength (unit: kgf / mm ² ), and the numerical value was confirmed.

As can be seen from FIG. 6, even if the maximum thickness of the electrode main film Fsp2 of the verification product 1-1 to 1-3 is the same as the thickness of the electrode main film Fsp2 of the comparison product, the external electrode of the verification product 1-1 The average value of the adhesion strength of E1 (about 0.90 kgf / mm ² ), the average value of the adhesion strength of the external electrode E1 of the verification product 1-2 (about 1.06 kgf / mm ² ), and the verification product 1-3 The average value (about 0.97 kgf / mm ² ) of the adhesion strength of the external electrode E1 is higher than the average value (about 0.73 kgf / mm ² ) of the adhesion strength of the comparative external electrode E1 ′. It was confirmed that the adhesion strength was improved.

<< Second Embodiment >>
The configuration of the sputtering apparatus 10 shown in FIG. 9 is the same as that shown in FIG.

<First step of external electrode formation>
In performing the first step, as shown in FIG. 9, the component holder J <b> 2 holding a large number of component main bodies CB is disposed on the upper surface of the lower sample stage electrode 14. Since the first step uses the component holder J2 as a target, it is not necessary to place a target on the lower surface of the upper target electrode 12.

  The component holder J2 has a flat plate shape having a predetermined thickness, and has a large number of recesses J2a on the upper surface thereof. Each recess J2a is for housing and holding a portion excluding a part of the component main body CB (external electrode forming portion CBa), and the surface of the external electrode forming portion CBa is exposed from the component holder J2 (FIG. 10). The component holder J2 is used as a target, and the material of the component holder J2 is preferably iron or an alloy mainly composed of iron such as stainless steel. Of course, titanium, chromium, tantalum, silicon, zirconium, an alloy containing at least one of these, or the like may be used as the material of the component holder J2.

  The component body CB becomes an electronic component such as a chip capacitor, a chip inductor, a chip resistor, or a piezoelectric chip by forming external electrodes, and has a substantially rectangular parallelepiped shape. The component main body CB is mainly made of ceramics and has functional elements such as an electrode layer, a coil, a resistance layer, and the like. The ceramic material that is the main material of the component body CB varies depending on the electronic component, but representative examples include barium titanate, strontium titanate, titanium oxide, aluminum oxide, and lead zirconate titanate.

  Then, an inert gas is introduced from the gas supply source into the chamber 11 through the first port 11a, and the degree of vacuum in the chamber 11 is adjusted through the second port 11b by a vacuum pump. In the magnetic field formation, contrary to the first step of the << first embodiment >>, the upper target electrode 12 is the positive electrode and the lower sample stage electrode 14 is the negative electrode. A voltage is applied for a predetermined time.

The inert gas introduced into the chamber 11 is preferably argon, but may be neon, xenon, or the like. Moreover, although it changes with the specifications of the sputtering apparatus 10, the inert gas introduction amount into the chamber 11 is set to a value within the range of 1 to 1000 sccm, and the degree of vacuum within the chamber 11 is approximately within the range of 10 ^{−2 to} 100 Pa. The high DC voltage applied to both electrodes 12 and 14 is set to a value in the range of approximately 10 to 10000 W when expressed as power, and the application time of the high DC voltage is approximately in the range of 100 to 300 sec. Is set to the value of

  As a result, as shown in FIGS. 9 and 10, the inert gas is turned into plasma, and the positive ions II collide with the component holding jig J2, and metal particles (points to atoms and molecules) from the surface of the component holding jig J2. SP3 is bounced off, and the bounced metal particles SP3 adhere to the surface of the external electrode forming portion CBa of each component body CB in a scattered state.

  The important point in this first step is to attach the metal particles SP3 in a scattered state on the surface of the external electrode forming portion CBa of the component main body CB. The particle size of the metal particles SP3 blown off from the surface of the component holding jig J2 is on the order of nm. However, if the application time of the high DC voltage is lengthened, the metal particles SP3 are deposited on the surface of the external electrode forming portion CBa of the component body CB. In this case, the formation of the film is avoided by shortening the application time of the high DC voltage as much as possible. Incidentally, when the surface coverage of the metal particles SP3 adhering to the surface of the external electrode forming portion CBa of the component main body CB is represented by a numerical value, it is within a range of 30 to 90%.

<Second step of external electrode formation>
When performing the second step following the first step, the target TA4 is disposed on the lower surface of the upper target electrode 12, as shown in FIG.

  The target TA4 has a flat plate shape with a predetermined thickness. The material of the target TA4 is a material that becomes an electrode main film of the external electrode, and is preferably copper or nickel.

  Then, an inert gas is introduced from the gas supply source into the chamber 11 through the first port 11a, and the vacuum level in the chamber 11 is adjusted through the second port 11b by a vacuum pump. A high DC voltage is applied to the electrodes 12 and 14 for a predetermined time from a DC power source 15 with the target electrode 12 as a negative electrode and the lower sample stage electrode 14 as a positive electrode.

The inert gas introduced into the chamber 11 is preferably argon, but may be neon, xenon, or the like. Moreover, although it changes with the specifications of the sputtering apparatus 10, the inert gas introduction amount into the chamber 11 is set to a value within the range of 1 to 1000 sccm, and the degree of vacuum within the chamber 11 is approximately within the range of 10 ^{−2 to} 100 Pa. The high DC voltage applied to both electrodes 12 and 14 is set to a value in the range of approximately 10 to 10000 W when expressed as power, and the application time of the high DC voltage is approximately in the range of 10 to 300 sec. Is set to the value of

  As a result, as shown in FIGS. 11 and 12, the inert gas is turned into plasma, the positive ions II collide with the target TA4, and the metal particles (pointing to atoms or molecules) SP4 fly off from the surface of the target TA4. Then, the blown-off metal particles SP4 are deposited on the surface of the external electrode forming portion CBa of each component body CB so as to cover the metal particles SP3, thereby forming the electrode main film Fsp4.

  The important point in the second step is that the electrode main film Fsp4 is formed by depositing the metal particles SP4 on the surface of the external electrode forming portion CBa of the component main body CB so as to cover the metal particles SP3. Here, the electrode main film Fsp4 covering the metal particles SP3 is formed by setting the application time of the high DC voltage to a time suitable for film formation. Incidentally, when the maximum thickness of the electrode main film Fsp4 is expressed by a numerical value, it is a value within a range of 0.5 to 10 μm, preferably 1 to 3 μm.

<Third step of external electrode formation>
When performing the third step following the second step, the target TA4 is removed and the direction of each component body CB held by the component holder J2 is reversed and held again, and then the component holder J2 is removed. It is arranged on the upper surface of the lower sample stage electrode 14.

  Then, under the same conditions as in the first step, an inert gas was introduced from the gas supply source into the chamber 11 through the first port 11a, and the degree of vacuum in the chamber 11 was adjusted through the second port 11b by a vacuum pump. In this state, a high DC voltage is applied to both electrodes 12 and 14 for a predetermined time from the DC power source 15 with the upper target electrode 12 as a positive electrode and the lower sample stage electrode 14 as a negative electrode, with no magnetic field formed or with a magnetic field formed.

  As a result, as in the first step, the inert gas is turned into plasma, and positive ions II collide with the component holding jig J2, and metal particles (pointing to atoms and molecules) SP3 fly off from the surface of the component holding jig J2. The blown-off metal particles SP3 adhere to the surface of the external electrode forming portion CBa of each component body CB in a scattered state. The important points in the third step are as described in the first step.

<Fourth step of external electrode formation>
When performing the fourth step following the third step, the target TA4 is disposed on the lower surface of the upper target electrode 12.

  Then, under the same conditions as in the second step, an inert gas was introduced from the gas supply source into the chamber 11 through the first port 11a, and the degree of vacuum in the chamber 11 was adjusted through the second port 11b by a vacuum pump. In this state, under magnetic field formation, a high DC voltage is applied to both electrodes 12 and 14 for a predetermined time from the DC power source 15 with the upper target electrode 12 as a negative electrode and the lower sample stage electrode 14 as a positive electrode.

  As a result, as in the second step, the inert gas is turned into plasma, the positive ions II collide with the target TA4, and metal particles (pointing to atoms or molecules) SP4 are blown off from the surface of the target TA4. The metal particles SP4 thus deposited are deposited on the surface of the external electrode forming portion CBa on the opposite side of each component body CB so as to cover the metal particles SP3, thereby forming the electrode main film Fsp4. The important points in the fourth step are as described in the second step.

<Electronic components with external electrodes on the component body>
FIG. 13 shows electronic components such as a chip capacitor, a chip inductor, a chip register, and a piezoelectric chip in which external electrodes E2 are formed at both ends of the component main body CB through the first to fourth steps. Here, the external electrode E2 includes metal particles SP3 adhering to the surface of the external electrode forming portion CBa of the component body CB in a scattered state, and electrodes formed so as to cover the metal particles SP3 on the surface of the external electrode forming portion CBa. It consists of a main membrane Fsp4.

<Effects obtained by electronic parts and manufacturing method thereof>
As can be seen from FIG. 10, since the metal particles SP3 are attached in a scattered state on the surface of the external electrode forming portion CBa of the component body CB, there are places where the metal particles SP3 exist on the surface of the external electrode forming portion CBa. A portion that is convex and does not exist (a portion where the surface of the external electrode forming portion CBa is exposed) is concave. Further, as can be seen from FIG. 12, the electrode main film Fsp4 is formed on the surface of the external electrode forming portion CBa so as to cover the metal particles SP3 adhering in a scattered state, and thus the electrode main film Fsp4 has the concave portion. A maximum thickness portion that enters and reaches the surface of the external electrode forming portion CBa and a thin portion that does not enter the recess are mixed.

  That is, the electrode main film Fsp4 has an effect of increasing the total adhesion area as compared with the case where the electrode main film Fsp4 is directly formed on a flat surface (see FIG. 15), and the shape of the metal particle SP3. Therefore, the adhesion strength of the electrode main film Fsp4 can be improved. Further, since the adhesion strength can be improved even if the maximum thickness of the electrode main film Fsp4 corresponding to the thickness of the external electrode E2 is set to the minimum value that covers the metal particles SP3, the maximum thickness of the electrode main film Fsp4 can be increased. The thickness of the external electrode E2 can be reduced by reducing the thickness.

  In short, according to the electronic component, by adopting the external electrode structure having no electrode base film, the thickness of the external electrode E2 can be effectively reduced and the adhesion strength can be effectively improved. According to this, an electronic component capable of obtaining the above-described effect can be accurately manufactured.

<Verification of effect>
When verifying the above-mentioned effects, particularly the improvement in adhesion strength, five verification products 2-1 to 2-3 (see FIG. 13) and comparative products (see FIG. 15) were prepared, and an adhesion strength test was performed on each. To confirm the result.

The verified products 2-1 to 2-3 are obtained by forming an external electrode E2 on a component main body (a main component of barium titanate) of a 0603 size chip capacitor as the component main body CB. E2
[Verification product 2-1]
(Conditions for the first step and the third step)
・ Inert gas: Argon ・ Introducing amount of inert gas: 50 sccm
・ Vacuum degree of chamber 11: 5 Pa
・ DC power: 200W
-DC power application time: 60 sec
-Parts holding jig J2: Surface coverage of iron / metal particles SP3: 50%
(Conditions for the second step and the fourth step)
・ Inert gas: Argon ・ Introducing amount of inert gas: 100 sccm
・ Vacuum degree of chamber 11: 3 Pa
・ DC power: 100W
-DC power application time: 180 sec
・ Target TA4: Copper ・ Maximum thickness of electrode main film Fsp4: 1 μm
[Verification product 2-2]
(Conditions for the first step and the third step)
・ Inert gas: Argon ・ Introducing amount of inert gas: 200 sccm
・ Vacuum degree of chamber 11: 20 Pa
・ DC power: 50W
-DC power application time: 120 sec
-Parts holding jig J2: Surface coverage of iron / metal particles SP3: 60%
(Conditions for the second step and the fourth step)
Same as verification product 2-1 [Verification product 2-3]
(Conditions for the first step and the third step)
・ Inert gas: Argon ・ Introducing amount of inert gas: 50 sccm
・ Vacuum degree of chamber 11: 40 Pa
・ DC power: 50W
-DC power application time: 240 sec
-Parts holding jig J2: Surface coverage of iron / metal particles SP3: 50%
(Conditions for the second step and the fourth step)
It formed according to the said 1st step-the 4th step on the same conditions as the verification product 2-1.

On the other hand, the comparative product is a component body of a 0603 size chip capacitor (a main component of barium titanate) as the component body CB, and the external electrode E2 ′ is
[Comparative product]
(Conditions for the first step and the third step)
The first step and the third step are not performed (conditions of the second step and the fourth step)
It was formed according to the second step and the fourth step in the same manner as the verification product 2-1. As can be seen from FIG. 15, the external electrode E2 ′ as a comparative product is “metal particles adhering to the surface of the external electrode forming portion CBa in a scattered state, such as verification products 2-1 to 2-3 (see FIG. 13). It does not have “SP3” and consists only of the electrode main film Fsp4.

The method for the adhesion strength test is the same as the test method described above with reference to FIG. As can be seen from FIG. 14, even if the maximum thickness of the electrode main film Fsp4 of the verification products 2-1 to 2-3 is the same as the thickness of the comparative electrode main film Fsp4, the external electrodes of the verification product 2-1 The average value of the adhesion strength of E2 (about 0.92 kgf / mm ² ), the average value of the adhesion strength of the external electrode E2 of the verification product 2-2 (about 1.06 kgf / mm ² ), and the verification product 2-3 the average value of the adhesion strength of the external electrodes E2 (about 1.0 kgf / mm ²⁾ are both higher than the average value of the adhesion strength of the external electrodes E2 'of the comparative article (about 0.73kgf / mm ^2), It was confirmed that the adhesion strength was improved.
<< Other embodiments >>
(1) In the first embodiment and the second embodiment, the electronic component in which the external electrode E1 or E2 is formed at both ends of the component main body CB is shown. However, the external electrode forming portion CBa is formed at the end of the component main body CB. There is no limitation, and the same effect as described above can be obtained even when an external electrode equivalent to the external electrode E1 or E2 is formed on a surface portion other than the end.

  (2) In the first embodiment and the second embodiment, the metal particles SP1 or SP3 adhering to the surface of the external electrode forming portion CBa of the component main body CB in a scattered state and the surface of the external electrode forming portion CBa of the component main body CB. 2 shows an electronic component having external electrodes E1 and E2 composed of an electrode main film Fsp2 or Fsp4 formed so as to cover the metal particles SP1 or SP3, but for soldering on the surface of the electrode main film Fsp2 or Fsp4. A second electrode main film, for example, an electrode main film made of tin formed by sputtering similar to the electrode main film Fsp2 or Fsp4 may be used as the external electrode. Even in this case, the same effect as described above can be obtained with respect to the portion of the external electrode excluding the second electrode main film.

  (3) In the first and second embodiments, the DC magnetron type sputtering apparatus in which the target electrode 12 is provided on the upper side and the sample stage electrode 14 is provided on the lower side is shown. The same external electrode as described above can be formed by using a DC magnetron type sputtering apparatus provided on the upper side and provided with the target electrode 12 on the lower side.

  (4) In the first embodiment and the second embodiment, the electronic component in which the external electrode is formed using the DC magnetron type sputtering apparatus is shown. However, a method other than the magnetron method, for example, a two-pole method or a three-pole method is used. Even if the sputtering apparatus uses a quadrupole method, an ECR (electron cyclotron resonance) method, an ion beam method, or the like, the same external electrode can be formed, or a sputtering device using an RF power source in the above method can be used. An external electrode similar to the above can be formed.

  DESCRIPTION OF SYMBOLS 10 ... Sputtering device, 11 ... Chamber, 12 ... Upper target electrode, 13 ... Magnet, 14 ... Lower sample stand electrode, TA1, TA2, TA4 ... Target, J1, J2 ... Component holding jig, CB ... Component main body, CBa ... External electrode forming portion, SP1, SP3 ... metal particles, Fsp2, Fsp4 ... electrode main film, E1, E2 ... external electrodes.

Claims (6)

An electronic component having external electrodes on the surface of the component body,
The external electrode includes metal particles attached in a scattered state on the surface of the external electrode forming portion of the component body, and an electrode main film formed on the surface of the external electrode forming portion of the component body so as to cover the metal particles. Consisting of,
An electronic component characterized by that. The component body is mainly made of ceramics.
The electronic component according to claim 1. The metal particles are particles of iron or an alloy containing iron as a main component, and the electrode main film is copper or nickel.
The electronic component according to claim 1, wherein the electronic component is an electronic component. A method of manufacturing an electronic component comprising a step of forming an external electrode on the surface of a component body,
The external electrode forming step includes (1) a step of depositing metal particles in a scattered state on the surface of the external electrode forming portion of the component main body by a sputtering method, and (2) an external electrode forming portion of the component main body by a sputtering method. Forming an electrode main film so as to cover the metal particles on the surface,
An electronic component manufacturing method characterized by the above. The component body is mainly made of ceramics.
The manufacturing method of the electronic component of Claim 4 characterized by the above-mentioned. The metal particles are particles of iron or an alloy containing iron as a main component, and the electrode main film is copper or nickel.
The method of manufacturing an electronic component according to claim 4 or 5, wherein

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