JPH0394409A - Electronic component and electrode paste; formation of terminal electrode - Google Patents

Abstract

PURPOSE:To obtain a terminal electrode part whose cost is low, whose solderability is good, whose drop in a solderability due to oxidation on the surface of an element is small and whose relaxation effect of a thermal shock property to the element during a soldering operation is excellent by a method wherein a metal phase contained in the terminal electrode part is composed of a copper alloy containing at least one component out of a group composed of lead, tin and zinc. CONSTITUTION:A terminal electrode part which contains a metal phase and an inorganic glass phase is provided; the metal phase is composed of a copper alloy containing at least one component out of a group composed of lead, tin and zinc. A cross section of the terminal electrode part is constituted so as to have the following: an intermediate layer composed of a metal phase composed mainly of copper or nickel, a metal phase composed mainly of lead, zinc or tin and a mixed texture phase containing at least two kinds selected from a group composed of intermetallic compound layers of these or a solid solution alloy phase; and a surface layer whose content of lead, tin or zinc is more than the intermediate layer as an average composition. Thereby, it is possible to obtain the terminal electrode part whose cost is low, solderability is good, drop in a solderability due to oxidation on the surface of an element is small and relaxation effect of a thermal shock property to the element during a soldering operation is excellent.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electronic component in which metal powder is baked onto the terminal electrode part, an electrode paste used in forming the terminal electrode, and a method for forming the terminal electrode. The present invention relates to a structure of a terminal electrode part which has good solderability to a part and has an excellent effect of alleviating thermal shock to an element during soldering, an inexpensive and simple method of forming the same, and an electrode paste.

Conventional technology In recent years, as circuits have become smaller and more dense, it has become common to surface-mount electronic components on circuit boards, and surface-mounted components have become mainstream, especially for circuit components. It has become.

Among these, in electronic components such as fixed resistance elements and multilayer capacitor elements, the terminal electrode portion has a metal glaze type structure in which sintered metal powder is fixed to the element body with a glass frit. This part is soldered directly onto the wiring metal of the circuit board, so it has good wettability with solder.
In addition, measures are taken to prevent the solder erosion phenomenon in which the terminal electrode portion is melted and lost by the molten solder of the solder flow.

Silver electrodes, which can be fired in air, have usually been used as the metal material for the terminal electrodes of such elements, but in order to solve the above-mentioned problems, methods using silver and palladium alloys, and methods using baked-in materials have been proposed. Techniques such as applying nickel plating to the outside of the silver terminal electrode and then applying tin-lead plating (solder plating) on top of that were used.

Also, when soldering the device and the wiring on the board, if the device terminal comes into contact with molten solder, a large tensile stress will be generated in a part of the device due to the difference in thermal expansion caused by the temperature difference between the terminal electrode and the device. In some cases, cracks appeared in the element. For this reason, measures have been taken to prevent rapid temperature differences by preheating the elements before soldering, if necessary.

On the other hand, due to the demand for lower cost of elements, there is a demand for using base metals such as copper and nickel for the terminal metals. For those fired with
For example, US Pat. No. 3,920,781 has already proposed the use of base metals such as copper and nickel for terminal electrodes. Although such base metal terminal electrodes are relatively free from solder erosion, they have problems with solderability, particularly a decrease in solder wettability due to oxidation of the terminal electrode surface.

For this reason, methods such as applying solder plating to the outer layer of the terminal electrode have been considered as in the past. In addition, cracks occur in the element during soldering, similar to conventional silver thread electrodes, so
Preheating the elements during soldering is also being considered as necessary.

Problems to be Solved by the Invention Forming a solder layer on the outermost layer of a terminal electrode by the above-mentioned plating method is a method of improving solderability and preventing oxidation of the terminal electrode surface, but it requires an additional process. In addition to the complexity and increased cost, it is necessary to place the element into the plating liquid phase, which may lead to alteration of the element and deterioration of characteristics due to the plating liquid.

Furthermore, the plating method was not effective in preventing cracks from forming inside the element during soldering.

In view of the above problems, the present invention provides an electronic component having a metal glaze type terminal electrode, which is low in cost, has good solderability, has less deterioration in solderability due to oxidation of the element surface, and has a metal glaze type terminal electrode. It is an object of the present invention to provide a structure of a terminal electrode part having an excellent effect of alleviating thermal shock properties, an inexpensive and simple manufacturing process thereof, and an electrode paste.

Means for Solving the Problems The present invention provides an electronic component having a terminal electrode portion consisting of a metal phase and an inorganic glass phase, in which the metal phase contained in the terminal electrode portion contains at least one component of the group consisting of lead, tin, and zinc. , made of copper alloy or nickel alloy.

In the structure of the terminal electrode of the present invention, the cross section of the terminal electrode portion is composed of a metal phase mainly composed of copper or nickel, a metal phase mainly composed of lead, zinc or tin, and an intermetallic compound layer of these. A structure having an intermediate layer consisting of a mixed texture phase or a solid solution alloy phase containing at least two types selected from the group, and further having a surface layer having a higher content of lead, tin or zinc as an average composition than the intermediate layer. do.

The electrode paste used in the terminal electrode of the present invention may include a metal component in the electrode paste that does not generate a liquid phase by itself during the baking process, or a metal component that melts, decomposes and melts alone to generate a liquid phase; Contains two types of components: a metal component that generates a liquid phase through a eutectic reaction with a metal component that does not generate a liquid phase when alone, and the solidified phase of the liquid phase component that is generated consists of lead, zinc, and tin. The electrode paste is characterized in that it contains at least one component selected from the group consisting of:

In addition, the method for forming the terminal electrode of the present invention includes adding a metal component that does not generate a liquid phase by itself during the baking process to the electrode paste, and a metal component that alone melts, decomposes and melts to generate a liquid phase, or the former alone generates a liquid phase. Contains two types of metal components: a metal component that generates a liquid phase through a eutectic reaction with a metal component that does not generate a liquid phase, and during the baking process, the eutectic phenomenon or monomerization of these metal powders, intermetallic compound powders, and alloy powders occurs. A forming method is used in which the process is carried out at a temperature higher than the temperature at which a liquid phase is partially formed between the metals or intermetallic compounds by melting the metal or intermetallic compound.

Since the metal phase contained in the working terminal electrode part is made of a copper alloy or a nickel alloy containing at least one component of the group consisting of lead, tin, or zinc, the terminal electrode part can be easily bonded to a solder molten metal made of a lead-tin alloy. The wettability is improved and the oxidation reaction is suppressed, thereby improving solderability caused by surface oxidation of the terminal electrode portion.

Since the surface layer of the terminal electrode part is made of a metal layer containing as a main component at least one component from the group consisting of lead, tin, or zinc, the wettability of the solder molten metal made of a lead-tin alloy and the terminal electrode part is improved. Furthermore, by suppressing the oxidation reaction on the surface, the decrease in solderability due to oxidation on the surface of the terminal electrode portion is improved.

Also, a mixed structure phase containing at least two selected from the group consisting of a metal phase mainly composed of copper or nickel, a metal phase mainly composed of lead, zinc, or tin, and an intermetallic compound phase thereof. Alternatively, the intermediate layer made of an alloy phase lowers the thermal conductivity of the four poles of the terminal 'F, and thus has the function of mitigating the thermal shock in the vicinity of the ceramic terminal electrode interface of the element when immersed in molten solder metal.

In addition, the conditions for forming the terminal electrode are above the temperature at which a liquid phase is partially formed between the metal or intermetallic compound powders due to eutectic phenomenon or melting of one of the metal powders, intermetallic compound powders, and alloy powders during the baking process. By performing this treatment, components containing a large amount of lead, zinc, or tin, which partially become a liquid phase during the baking process of the electrode, are segregated to the surface, so that the desired electrode configuration can be obtained.

In addition, as a starting material for the electrode paste, at least two metals selected from metal powders containing copper or nickel as a main component, metal powders containing lead, zinc, or tin as a main component, or metal powders consisting of intermetallic compounds thereof. By using a powder mixture or alloy powder, a liquid phase with a high content of lead, tin, or zinc is generated during the baking process of the electrode, and the liquid phase components are segregated to the surface during the cooling process, making it difficult to achieve the desired electrode configuration. It becomes easier to obtain.

Examples Examples of the present invention will be described below with reference to the drawings.

Example 1 A fixed resistor element was considered as the element.

The resistor used was a glazed resistor made of rhenium oxide-zinc borosilicate glass baked on an alumina substrate at 650°C.

As a starting material for the terminal electrode, the particle size is 1.5 μm or less.
A powder made by mixing 12 wt% of glass frit with a particle size of 0.8 μm in a metal powder made by mixing metal steel, metal lead, metal tin, and metal zinc in a predetermined ratio of 5 μm or more is used, and this is mixed with acrylic resin and petroleum solvent. A paste made by mixing these was used.

The terminal electrode paste was applied to both ends of the resistor by the dib method, dried in air at 80°C, heated to 280°C over 5 hours in an electric furnace with a nitrogen gas flow and an oxygen concentration of about 21) pm, and then heated to 280°C over 5 hours. The temperature was raised from 550°C to 600°C over 30 minutes, held for 15 minutes, and then cooled to room temperature.

After the terminal electrodes were formed, the device was held under the following holding conditions A and B.

A: Hold in air for 14 hours B: Hold in an atmosphere of 40°C and humidity 60% for 60 hours After that, the device was temporarily attached to a glass epoxy board with copper wiring using an organic adhesive, and reflow soldering was performed at 230°C. death,
The number of soldering defects among the 50 samples was determined. Defective soldering The soldered area was visually observed after flow soldering, and those in which a portion to which no solder was attached were clearly observed were determined to be defective.

Table 1 shows the terminal electrode composition, holding conditions, and number of defects.

(Leaving space below) Table 1 Table 1 Continued Table 1 Continued As is clear from Comparative Example Table 1, Nos. and 22 used copper or nickel electrodes containing either lead, tin, or zinc as the terminal electrodes. Compared to products that do not contain these, solderability, especially after storage under conditions where terminal electrodes are easily oxidized, is improved.

Regarding the content range of each component, the lead content of the alloy containing lead and copper is 0. 3 to 70 wt% (No. 3 to 8 in Table 1), and the tin content of the alloy containing copper and tin is 0. 8 to 65 wt% (Nos. 9 to 13 in Table 1), and the zinc content of the alloy containing copper and zinc is 0. 5~
80 wt% (No. 16 to 20 in Table 1), and the lead content of the alloy containing nickel and lead is 1.5 to 45 wt% (
No. 24 to 27 in Table 1), the tin content of the alloy containing nickel and tin is 1.5 to 55 wt% (No. 24 to 27 in Table 1),
30 to 34) or an alloy containing nickel and zinc with a zinc content of 1.5 to 65 wt% (No. 3 in Table 1)
7 to 41) are preferred.

If the content is less than these ranges (No. 2 in Table 1).
8+ 15+ 23y 29 and 36) The effect of improving solderability is small, and if the content exceeds this range (No. 7.14, 21.28.35 and 42 in Table 1), the electrode metal will partially melt. , the adhesion between the terminal electrode part and the element body is reduced before soldering, and peeling occurs from that part during soldering, and although the solderability itself does not decrease, the number of defects tends to increase. However, compared to the conventional example using only copper (No. 1 in Table 1), the number of soldering defects is reduced under all conditions. In addition, when compared with the conventional example using nickel alone (No. 22 in Table 1), the number of soldering defects was reduced under condition B, but a slight increase was observed under condition A. However, considering that the number of defects is originally small under Condition A using nickel alone, and that the number of defects is reduced in an atmosphere that is more easily oxidized than Condition A (Condition B), it is still effective in this range. It is assumed that there is.

Example 2 A ceramic multilayer capacitor with copper internal electrodes was studied as an element.

A lead composite berovskite dielectric whose main component is Pb (Mg+73Nba73)Os is used for the dielectric ceramic of the multilayer capacitor element, which is formed into a sheet, and then internal electrodes are formed on top of it using copper oxide electrode paste. After forming layers, laminating them, and burning out in air, only the internal electrode layers were metallized in a hydrogen gas atmosphere at a temperature lower than the firing temperature, and fired in a nitrogen atmosphere to create an element.

Terminal electrodes were formed in the same manner as in Example 1, and after the terminal electrodes were formed, the device was held under the following holding conditions A and B.

A: Hold in air for 14 hours B: Hold for 60 hours in a 40"C atmosphere with 60% humidity. After that, the device is temporarily fixed to a glass epoxy board with copper wiring using an organic adhesive, and then reflow soldered at 230°C. The number of soldering defects among the 50 samples was calculated.The soldered parts were observed using the visual method after soldering failure beams and flow soldering, and those in which areas with no solder were clearly observed were considered defective. did.

Table 2 shows the terminal electrode composition, holding conditions, and number of defects.

(The following is a margin) Table 2 Nos. 50 and 5I are Comparative Examples As is clear from Table 2, elements having terminal electrodes made of copper or nickel containing at least lead, tin, or zinc have significantly improved solderability.

In this example, an example was shown in which copper was used as the internal electrode, but the same effect could be obtained even if other base metals were used as the internal electrode.

Example 3 A fixed resistor element was considered as the element.

The resistor used was a glazed resistor made of rhenium oxide-zinc borosilicate glass baked at 950° C. on an alumina substrate.

Starting materials for terminal electrodes include particles with a particle size of 5.5 μm or less, 1
．． Mix metal steel of 5 μm or more and metal lead powder in a predetermined ratio,
Average particle size 0. A powder containing 8 μm zinc borosilicate glass frit at 8 wt% based on the metal weight was used, and an acrylic resin with an average molecular weight of 1800 was mixed at 5 wt% based on the powder weight.
wt%, α-terpineol, toluene mixed solvent (8:
4) was added in an amount of 30 wt % based on the powder weight, mixed in a mortar, and then kneaded using three rolls. Further, the amount of solvent was adjusted to prepare an electrode paste with a viscosity of 8000 centipoise at 20°C.

The electrode paste was applied to both ends of the resistor by the dipping method, dried in air at 80°C, and heated to 280″C for 5 hours in a tubular electric furnace core tube in which the oxygen concentration was adjusted to about 2 ppm by flowing nitrogen gas. After increasing the humidity by heating, the temperature is 550~
The temperature was raised to 800° C. over 30 minutes, maintained for 5 minutes, and then lowered to room temperature over 30 minutes.

The cross section of the terminal electrode portion of the fabricated device was examined for the composition distribution of the electrode metal using an X-ray microanalyzer and an X-ray microdiffractometer.

A schematic diagram is shown in Figure 1. The resistor is a ceramic element 11
and a glaze resistor 15.

The part of the electrode part of the resistor closest to the element body is a base layer 1 containing an inorganic frit partially fused to the ceramic element body 11.
Next, there is an intermediate layer 13 with a thickness of about 700 μm in which a copper metal phase and a lead metal phase form a mixed texture phase with a thickness of about 2 to 40 μm, and further a lead metal phase with a thickness of 0.3 μm to
It consists of a surface layer 14 of about 60 μm.

In a sample with a low lead content of about 0.1 wt%, almost no lead metal phase is observed in the intermediate phase 13.

After the terminal electrodes are formed, the device is held under the following holding conditions A. B was retained.

A: Hold in air for 14 hours B: Hold for 60 hours in an atmosphere of 40°C and 80% humidity After that, the device was temporarily attached to a glass epoxy board with copper wiring using an organic adhesive, and then reflow soldered at 230''C. The number of soldering defects was determined in 50 samples.Soldering defects After flow soldering, the soldered area was visually observed, and it was found that there were clearly areas on the terminal electrode surface where no solder was attached. marked something as defective.

Table 3 shows the failure rate of the metal powder mixture of the terminal electrode, the holding conditions, and the number of defects.

(The following is a blank space) Table 3 The initial characteristics of the manufactured elements were measured, and those whose resistance value varied by 50% or more from the expected value were judged as defective. Table 4 shows the number of initial failures (100
(per).

In Table 4, No. 82 shows that in the sample of Comparative Example No. 83, almost no lead metal phase was observed in the intermediate layer, so the effect of reducing the number of defects under easy-to-oxidize conditions was small, but the reduction in the number of defects was observed compared to No. 82. It will be done.

A comparison was also made between No. 88 in Table 3 and the conventional method of applying solder plating to the surface of the terminal electrode. That is, a solder plating layer was formed on the surface of the terminal electrode of sample No. 62 by the barrel plating method in a solder plating solution (pH: 1.0) containing alkanol sulfonic acid as the main component.
No soldering defects occurred after o62 samples were stored under the above conditions A and B, except for the initially defective products.

As is clear from Tables 3 and 4, the surface has a higher content of lead, tin or zinc than the intermediate layer with copper or nickel containing at least one of lead, zinc or tin of the present invention. In a terminal electrode (as defined in claim 10) composed of layers, the solidified phase of the liquid phase component produced during the baking process contains at least one component selected from the group consisting of lead, zinc or tin. (Claim 1)
(described in Section 7) Using an electrode paste, a liquid phase is partially formed between the metals or intermetallic compounds due to the eutectic phenomenon or partial melting of the metal component metal powder, intermetallic compound, or metal powder during the baking process. If the manufacturing process involves baking at a temperature higher than the temperature at which the copper electrode is baked (as described in claim 25), the solderability will be improved, especially after storage under conditions where the terminal electrode is easily oxidized, compared to a single copper electrode. Solderability is improved, and there is less deterioration and fluctuation in initial characteristics compared to those with surface solder plating.

Further, the lead content in the electrode paste is 0. 3wt%
The content is preferably 70 wt% or less, and if the content is less than this range (No. 83 in Table 3), the effect of improving solderability will be small. If the content is higher than that range (No. 8 in Table 3)
8) The amount of melted electrode metal increases and the adhesion between the terminal electrode portion and the element body decreases, and this portion peels off during soldering, increasing the number of defects. However, the conventional example using copper alone (N in Table 3)
Compared to o62), the number of soldering defects is reduced under all conditions.

Example 4 A fixed resistor element similar to Example 1 was studied as an element.

The resistor used was a rhenium oxide-borosilicate glass glaze resistor baked at 1050°C.

As starting materials for terminal electrodes, particles with a particle size of 6 μm or less and 1.5
Metallic copper, metallic tin powder of μm or more, and average particle size of 1.5
A powder is used in which CuSN powder of μm is mixed in a predetermined ratio and zinc borosilicate glass frit with an average particle size of 1.0 μm is mixed at 4 wt% based on the metal weight, and an acrylic resin with an average molecular weight of 1800 is added to the powder by weight. 5wt%, α
Turbineol, calitol acetate mixed solvent (6
: 30 wt % of 4) was added to the powder weight, mixed in a mortar and kneaded using three rolls, and the solvent was further adjusted to prepare an electrode paste with a viscosity of 10,000 centivoise at 20°C.

The electrode paste was applied to both ends of the resistor by the dipping method, dried in air at 80°C, and heated to 280°C for 5 hours in a tubular electric furnace core tube in which the oxygen concentration was adjusted to about 2 ppm by flowing nitrogen gas. After heating up to 550~6
The temperature was raised to 00°C over 30 minutes, held for 5 minutes, and then lowered to room temperature over 30 minutes.

The distribution of M-pole metal was evaluated using an X-ray microanalyzer and an X-ray microdiffractometer on the cross section of the terminal electrode portion of the produced element.

A schematic diagram is shown in Figure 2. The resistor is a ceramic element 21
and a glaze resistor 25.

The part of the electrode portion of the resistor closest to the element body is a base layer 22 containing an inorganic frit partially fused to the ceramic element body 21.
followed by a copper metal phase (with some tin in solid solution), a tin metal phase and a Cusn1 CusSns intermetallic compound phase.
There is an intermediate layer 23 with a thickness of about 700 μm in which a mixed texture phase of about μm is formed, and an intermediate layer 23 with a thickness of about 2 μm consisting of a tin metal phase.
It consists of a surface Fl24 of about ~60 μm. Tin content is 0
．． In samples with a small content of about 1 wt%, the tin metal phase in the intermediate phase is hardly observed.

In addition, in a sample with a tin content of about 0.8 wt%, the intermediate phase 2
3 is a solid solution phase in which tin is dissolved in copper.

In addition, in the case where Cun SD was used as the starting material, the formation of a tin metal phase on the surface shown in the surface layer 24, which was observed in other samples, was not confirmed in the cross section of the terminal electrode.

After the terminal electrodes are formed, the device is held under the following holding conditions A. B was retained.

A: Hold in air for 14 hours B: Hold in an atmosphere of 40°C and humidity θO% for 60 hours After that, the device was temporarily fixed to a glass epoxy board with copper wiring using an organic adhesive, and then reflow soldered at 230°C. The number of soldering defects among the 50 samples was determined. Soldering defects After flow soldering, the soldered portions were visually observed, and those in which a portion of the terminal electrode surface to which no solder was clearly adhered were determined to be defective.

Table 5 shows the metal powder mixed composition ratio of the terminal electrode, raw material powder, holding conditions, and number of defects.

Table 5 NoG9 is a comparative example. In the sample No. 70 in Table 5, almost no tin metal phase was observed in the intermediate layer, and in No. 73, formation of a tin metal phase on the surface was not confirmed. As shown, the number of soldering defects decreased under both conditions.

As is clear from Table 5, the intermediate layer having copper or nickel containing at least one of lead, zinc or tin of the present invention and the surface having a higher content of lead, tin or zinc than the intermediate layer. A terminal electrode (as described in claim 10) consisting of a layer, an intermediate layer containing a mixed composition phase or a solid solution metal phase of copper with tin, and a metal whose main component is tin partially or entirely. The surface 1 (described in claim 12) of a phase or a mixed composition phase of copper and tin is formed, and the solidified phase of the liquid phase component generated during the baking process is
An electrode paste containing at least one component selected from the group consisting of lead, zinc, or tin (as described in claim 17) is used, and during the baking process, the metal component such as metal powder, intermetallic compound, or metal powder is mixed. Copper is manufactured by baking at a temperature higher than that at which a liquid phase is partially formed between metals or intermetallic compounds due to melting phenomenon or partial melting (as described in claim 25). Compared to a single electrode, the solderability is improved, especially after storage under conditions where terminal electrodes are easily oxidized.

Further, the lead content in the electrode paste is 0. 3wt%
The content is preferably 70 wt% or less, and if the content is less than this range (No. 70 in Table 5), the effect of improving solderability will be small. If the content is higher than that range (No. 7 in Table 5)
5) The amount of melted electrode metal increases, reducing the adhesion between the terminal electrode portion and the element body, resulting in peeling of that portion during soldering, increasing the number of defects. However, the conventional example using copper alone (N in Table 5)
o89), the number of soldering defects is reduced under all conditions.

In addition, as in sample No. 73, electrode paste is used in which no eutectic reaction or liquid phase formation due to melting of some metal powder occurs in the cross section of the terminal electrode at the baking temperature as in other samples, as shown in the phase diagram. In No. 73, the formation of a tin metal phase that segregates on the surface was not confirmed, and although the composition is the same as No. 73, a liquid phase is formed and a tin metal phase segregates on the surface.
Compared to sample No. 72, the effect of improving solderability when stored under conditions where the terminal electrodes are easily oxidized is slightly smaller.

On the other hand, in the case of sample No. 72, which uses an electrode paste composition in which tin metal melts, even temporarily, during the reaction process, formation of a tin metal phase on the surface is confirmed.

Baking treatment at a temperature higher than the temperature at which a liquid phase is partially formed between the metals or intermetallic compounds due to the eutectic phenomenon or partial melting of the metal powder, intermetallic compound, or metal powder of the metal component during the baking process. It becomes clear that partial liquid phase formation between metals (IrIli described in claim 25) is effective in forming a surface phase.

Example 5 A ceramic multilayer capacitor element using a barium titanate dielectric and nickel internal electrodes was studied.

As shown in FIGS. 3 to 5, the device consists of a dielectric ceramic body 31 with a thickness of 20 μm. 41. 51 layers are nickel internal electrodes 35, 45, 55 with a thickness of 2.1 μm.
! ! It has a structure in which a 60 μm ineffective layer is laminated on top and bottom with an outer diameter of 3. 2IIIIX 1. 6mmX
A 0.7+am element was used.

As a starting material for the terminal electrode, particles with a particle size of 8 μm or less and 1.5
Metal nickel, metal lead, metal tin, and metal zinc powders of μm or more are mixed in a predetermined ratio, and the average particle size is 0. A powder containing 8 μm zinc borosilicate glass frit at 4 wt% based on the metal weight was used, and an acrylic resin with an average molecular weight of 1800 was mixed at 5 wt% based on the powder weight, α-turbineol and acetic acid carbitol acetate mixed solvent (6:4). was added in an amount of 30 wt % based on the powder weight, mixed in a mortar, and then kneaded using three rolls. Further, the amount of solvent was adjusted to prepare an electrode paste with a viscosity of 8000 centipoise at 20°C.

The electrode paste was applied to both ends of the resistor by the dipping method, dried in air at 80°C, and then heated to 280°C in a tubular electric furnace core tube in which the oxygen concentration was adjusted to about O-5 ppm by flowing nitrogen gas. 650-800 after heating up over time
The temperature was raised to 0°C over 30 minutes, held for 5 minutes, and then lowered to room temperature over 30 minutes.

The cross section of the terminal electrode portion of the produced element was evaluated for the distribution of electrode metal using an X-ray microanalyzer and an X-ray microdiffractometer.

Schematic diagrams of products using lead, tin, and zinc powders as starting materials are shown in FIGS. 3 to 5, respectively.

The portion of the electrode portion closest to the element body consists of base layers 32, 42, 52 containing inorganic frit partially fused to the ceramic element body 3L 41, 51.

Next, in FIG. 3, there is an intermediate phase 33 in which a nickel metal phase and a lead metal phase form a mixed texture phase of about 30 μm.

In a sample with a lead content of 1.5 wt % or less, the intermediate layer 33 is confirmed as a single metallic phase in which a slight amount of lead is dissolved in nickel.

Furthermore, in Fig. 4, a metallic phase (10
There is an intermediate phase 43 in which a tin metal phase and an intermetallic compound phase form a mixed texture phase of about 20 μm.

In a sample with a tin content of 5 wt % or less, the intermediate phase 43 is confirmed as a single metallic phase in which tin is dissolved in nickel.

Furthermore, in Figure 5, a metallic phase (3
There is an intermediate phase 53 in which a zinc metal phase (zinc solid solution in a range of 0 wt % or less), a zinc metal phase, and an intermetallic compound phase thereof form a mixed texture phase of about 2 to 30 μm.

In a sample with a zinc content of 5 wt % or less, the intermediate phase 53 is confirmed as a single metallic phase in which zinc is dissolved in nickel.

In either case, the intermediate phase 33, 43.53 has a thickness of 70
It was about 0 μm.

Next, in FIG. 3, a surface layer 34 consisting of a lead metal phase, in FIG. 4 a surface layer 44 consisting of a tin metal phase, and in FIG. 5, a single zinc metal phase or a zinc metal phase and an intermetallic compound phase of zinc and copper There is a surface phase 54 consisting of.

In both cases, the thickness of the surface layer is 0. It was about 5 to 60 μm.

Samples that do not contain lead, tin, or zinc and whose content is O. lwt
In samples with a small amount of about 50%, almost no surface layer is observed.

After the terminal electrodes were formed, the device was held under the following holding conditions A and B.

A: Hold in air for 14 hours B: Hold in an atmosphere of 40°C and humidity 60% for 60 hours After that, the device was temporarily attached to a glass epoxy board with copper wiring using an organic adhesive, and then reflow soldered at 230''C. The number of soldering defects was determined in 50 samples.Soldering defects After flow soldering, the soldered area was visually observed, and it was found that there were clearly areas on the terminal electrode surface where no solder was attached. marked something as defective.

Table 6 shows the number of defects depending on the metal powder mixture composition ratio of the terminal electrode and the holding conditions.

In addition, for comparison with the conventional method, a solder plating layer was formed on the terminal electrode surface of the N076 sample by barrel plating in a solder plating solution (pH: 1.0) containing alkanolsulfonic acid as a main component.

The prepared devices and devices No. 77 to 82 were placed in a soldering bath at 350°C without any preheating treatment, and then the devices were polished to the center line including both terminal electrodes, and cracks near the edges of the side surfaces of the terminal electrodes were removed. The presence or absence of cracks was investigated, and the number of crack defects in each of the 50 samples was determined. Table 7 shows the number of crack defects (per 50 pieces)
shows.

Table 6 Table 6 Continued No. 7B is Comparative Example 7 Table 7 Continued No. 9G is Comparative Example Table 6 Continuing No. 7B is Comparative Example No. 7 Continued from Table 6 Comparative Example A terminal electrode (as claimed in claim 10) comprising a surface layer having a higher content of lead, tin or zinc than an intermediate layer having a solidified phase of liquid phase components generated during the baking process. contains at least one component selected from the group consisting of lead, zinc or tin (as described in claim 17)
Using an electrode paste, the temperature is higher than the temperature at which a liquid phase is partially formed between the metals or intermetallic compounds due to eutectic phenomenon or partial melting of the metal powder, intermetallic compound, or metal powder of the metal component during the baking process. When the baking process (described in claim 25) is used, the solderability is improved compared to the nickel electrode alone (No. 78 in Table 6), especially after storage under conditions where the terminal electrode is easily oxidized. Improves solderability.

In addition, lead in the electrode paste is 1.5 to 45 wt% (as described in claim 22), and tin is 1.5 to 55 wt% (
(as described in claim 23), or zinc is 1.
The content is preferably in the range of 5 to 65 wt% (described in claim 24), and if the content is less than that range (No. 77, 83.89 in Table 6), the effect of improving solderability will be small. , if the content is higher than that range (N in Table 6)
o 8 2+88.94) The amount of melted electrode metal increases, the adhesion between the terminal electrode part and the element body decreases, and the part peels off during soldering, increasing the number of defects.

Furthermore, as shown in No. 095 in Table 6, soldering defects were similarly reduced in copper and nickel based materials.

Furthermore, as is clear from Table 7, the structure described in claim 10 is particularly suitable for metal nickel, metal lead, metal tin,
No 9 6, 9 7, 1 in which there is an intermediate layer in which metallic zinc and their intermetallic compound phases form a mixed texture phase
Samples other than 0 3 and 1 0 9 are less prone to crack defects due to thermal shock, whereas samples other than 0 9 8 and 9 7
, 1 0 3 and 1 0 9, in which the intermediate phase is made of a single nickel metal phase, are susceptible to cracking.

Therefore, the content of lead, tin, and zinc is 1.
5 to 45 wt% (as described in claim 22), 1.5 to 55 wt% for tin (as described in claim 23), and 1.5 to 65 wt% for zinc (as described in claim 23). Range (described in item 24) is preferred. This means that the terminal electrode (of the present invention) consisting of a surface layer having a higher content of lead, tin or zinc than the intermediate layer having copper or nickel containing at least one of lead, zinc or tin.
(as set forth in claim 10), a terminal electrode having an intermediate layer containing at least lead and a surface layer containing lead as a main component (as set forth in claim 14), an intermediate layer containing at least tin and a terminal electrode having a surface layer mainly composed of tin (as described in claim 15), a terminal electrode having an intermediate layer containing at least zinc and a surface layer mainly containing zinc (as claimed in claim 15) (described in Section 16), metallic nickel and metallic lead, which are different from the conventional example,
This shows that the intermediate phase consisting of a mixed structure phase of metallic tin or metallic zinc is effective in improving the thermal shock resistance of the device.

A similar effect was obtained with copper and nickel in Noll 5 in Table 7.

Example 6 A ceramic multilayer capacitor element using a lead composite perovskite dielectric and copper internal electrodes was studied.

As shown in Figures 6 and 7, the element has a thickness of 20 μm.
The dielectric ceramic body 81.71 layers have a thickness of 1.8
It has a structure in which copper internal electrodes with a thickness of 65.75 μm are laminated via layers, and invalid layers of 62 μm are laminated above and below. 2
mmX 1. 8mmX 0. A 7 mm element was used.

Starting materials for terminal electrodes include particles with a particle size of 8.5 μm or less, 1
．． Metallic copper, metallic lead, metallic zinc powder or intermetallic compound powder having a composition of CulZn4 of 0 μm or more is mixed at a predetermined ratio, and the average particle size is 0. Using a powder mixed with 8 μm zinc borosilicate glass frit at 4 wt% based on the metal weight,
To this, 5 wt% of an acrylic resin with an average molecular weight of 800 based on the powder weight, and 30 wt% of an α-terpineol and carbitol acetate mixed solvent (8:4) based on the powder weight.
In addition, the mixture was mixed in a mortar, kneaded using three rolls, and a solvent was added to prepare an electrode paste having a viscosity of 8000 centipoise at 20°C.

The electrode paste was applied to both ends of the resistor by a dipping method, and after drying in air at 80°C, it was placed in a tubular electric furnace core tube in which the oxygen concentration was adjusted to about 2 ppm by flowing nitrogen gas.
After raising the temperature to 80℃ over 5 hours, the temperature rises to 550-800℃.
Raise the temperature to room temperature over 30 minutes, hold for 5 minutes, and then raise the temperature to room temperature.
The temperature was lowered over 0 minutes.

The cross section of the terminal electrode portion of the fabricated device was evaluated for the distribution of electrode metal using an X-ray microanalyzer and an X-ray microdiffractometer.

One using zinc, Cu+Zn4 as a starting material,
Figures 6 and 7 are schematic diagrams of cross sections of products using lead.
Shown in the diagram.

The part of the electrode portion closest to the element body is a base layer 62 containing an inorganic frit partially fused to the ceramic elements 81 and 71;
There are 72.

Next, in FIG. 6, there is an intermediate layer 63 in which a metal phase containing copper as a main component, a zinc metal phase, and an intermetallic compound phase thereof form a mixed texture phase or solid solution phase of about 2 to 30 μm.

In a sample with a zinc metal content of 1.5 wt% or less, an intermediate phase exists as a single metal layer in which copper is dissolved in zinc.

In FIG. 7, there is an intermediate phase 73 in which a copper metal phase and a lead metal phase form a mixed texture phase of about 30 μm.

For samples with a lead content of 0.1 wt% or less, an intermediate phase is confirmed as a single copper metal phase.

Each intermediate phase has a thickness of about 500 μm.

Furthermore, in FIG. 6, a surface phase 64 consisting of a zinc metallic phase or a mixed structure phase of a lead and zinc intermetallic compound phase and a zinc metallic phase is shown.
exists.

In FIG. 7, a surface phase 74 consisting of a lead metal phase is present.

The thickness of any surface phase 64.74 is 0.3 μm to 80 μm
That's about it.

The surface phase 64.74 is not confirmed in samples with zinc and lead contents of 0.1 wt% or less.

After the terminal electrodes were formed, the device was held under the following holding conditions A and B.

A: Hold in air for 14 hours B: Hold in an atmosphere of 40°C and humidity 60% for 60 hours After that, the device was temporarily fixed to a glass epoxy board with copper wiring using an organic adhesive, and then reflow soldered at 230°C. The number of soldering defects among the 50 samples was determined. Soldering defects After flow soldering, the soldered portions were visually observed, and those in which a portion of the terminal electrode surface to which no solder was clearly adhered were determined to be defective.

Table 8 shows the number of defects depending on the metal powder mixed composition ratio of the terminal electrode, the starting composition, and the holding conditions.

Further, for comparison with the conventional method, a solder plating layer was formed on the surface of the terminal electrode of Noll 6 sample by barrel plating method in a solder plating solution (pH: 2.5) containing alkanolsulfonic acid as a main component.

The created elements and elements No. 1 1 6 to 128 are 3
After dipping the device into a 50″C solder bath without preheating, the device was polished to the center line including both terminal electrodes, and the presence or absence of cracks near the edge of the device side of the terminal electrode was examined. The number of crack defects was calculated.

Table 9 shows the number of crack defects (per 50 pieces).

Table 8 Table 9 Table Noll [i is Comparative Example No. 129] As is clear from Comparative Example Table 8, it is better than the intermediate layer having copper or nickel containing at least one of lead, zinc or tin of the present invention. The terminal electrode (recited in claim 10) is composed of a surface layer with a high content of lead, tin, or zinc, and the solidified phase of the liquid phase component generated during the baking process contains lead, tin, or zinc. Using an electrode paste containing at least a component selected from the group consisting of zinc or tin (as described in claim 17), the eutectic phenomenon of metal powder, intermetallic compound, or metal powder as a metal component is performed during baking treatment. Alternatively, those using a manufacturing process in which a part is melted and baked at a temperature higher than that at which a liquid phase is partially formed between metals or intermetallic compounds (as described in claim 25) are copper electrodes alone. (Compared to Nos. 1, 1, and 6 in Table 8), solderability, especially after storage under conditions where terminal electrodes are likely to oxidize, is improved.

Further, the zinc content in the electrode paste is preferably 1.5 wt% or more and 80 wt% or less as described in claim 21, and the lead content is 0.5 wt% or less as described in claim 19. It is preferably 3 wt% or more and 70 wt% or less.

If the content is less than that range (Nos. 117 and 123 in Table 8), the effect of improving solderability will be small, and if the content is more than that range (Nos. 122 and 128 in Table 8), the amount of melted electrode metal will be large. As a result, the adhesiveness between the terminal electrode portion and the element body deteriorates, and this portion peels off during soldering, increasing the number of defects.

Furthermore, as is clear from Table 9, claim 10
In particular, the thickness 70 in which the copper metal phase, the zinc metal phase, and the intermetallic compound phase form a mixed texture phase, or the copper metal phase and the lead metal phase form a mixed texture phase.
No. 1 with intermediate layer 63 or 73 of about 0 μm
Samples Nos. 31 to 135 and Nos. 137 to 141 are less prone to crack defects due to thermal shock, whereas No. 29 samples are less prone to crack defects due to thermal shock.
, 130, and 138, in which the intermediate phase consists of a single copper metal phase, cracks are likely to occur.

The content here also refers to claim 19 or 2.
As described in Section 1, in the case of zinc, 1.5 wt% or more8
0wt% or less is preferable, and in the case of lead, 0.3wt% or more7
It is preferably 0 wt% or less.

This means that, in the configuration of the terminal electrode section described in Claim No. 10, the mixed structure phase of metallic steel, metallic zinc, and their intermetallic compounds, or metallic copper and metallic lead, is different from the conventional example. This shows that the intermediate phase consisting of a mixed texture phase is effective in improving the thermal shock resistance of the device.

Example 7 A ceramic multilayer capacitor element using copper internal electrodes similar to Example 6 was investigated.

Starting materials for terminal electrodes include particles with a particle size of 3 μm or less; 1.
Metallic copper of 0μm or more and 80wt with a particle size of about 5μm
%Pb-20wt%Zn alloy powder, 80wt%Pb-
Alloy powder of 20 wt% Sn and 75 wt% Pb-2
A device similar to Example 4 was prepared by mixing 0 wt % Sn-5 wt % Bi alloy powder in a predetermined ratio.

The cross section of the terminal electrode portion of the fabricated device was evaluated for the distribution of electrode metal using an X-ray microanalyzer and an X-ray microdiffractometer.

The schematic diagram of the cross section is almost the same as FIG. 6 and FIG. 7 of Example 4, but the intermediate phase is a metallic phase mainly composed of copper, lead, tin,
The intermetallic compound phase of zinc and copper forms a mixed texture phase with a texture of about 2 to 60 μm, and the total thickness is about 500 μm.

Furthermore, the surface layer is a metal phase containing lead-tin, lead-zinc, or lead-tin-bismuth as a main component.

Each surface layer has a thickness of approximately 0.3 μm to 80 μm.

After forming the terminal electrodes, the device was held under the same conditions as in Example 4.
The same solderability test and thermal shock test as in Example 4 were conducted.

Table 10 shows the number of defects depending on the metal powder mixed composition ratio and holding conditions of the terminal electrode, and Table 11 shows the number of crack defects (both per 50 samples).

(The following is a margin) Table No. 14G has the structure described in Claim 10, as is clear from Comparative Example Table 10, and Comparative Example No. 14G has the structure described in Claim 10. Those using the described electrode paste and the manufacturing process described in claim 25 have better solderability than single copper electrodes, especially when the terminal electrodes are stored under conditions where they are easily oxidized. Improves ease of attachment.

Furthermore, as is clear from Table 11, the first claim
The structure described in item 0, especially N containing an intermediate phase layer in which a metal phase mainly composed of copper, a metal phase mainly composed of lead, tin, and zinc, and an intermetallic compound phase of these forms a mixed texture phase.
Samples of o 1 47 to 149 are less likely to develop cracks due to thermal shock, whereas samples whose intermediate phase consists of a single copper metal phase, such as sample No. 148, are more likely to develop cracks.

This means that in the structure of the terminal electrode section described in claim 10, the intermediate phase consisting of a mixed structure phase, which is different from the conventional example, is effective in improving the thermal shock resistance of the element. It shows.

In addition, even if it contains new ingredients other than lead, tin, and zinc as an electrode metal, such as No. 145 or No. 1 49, those with a structure that contains copper, nickel, lead, tin, and zinc as the main ingredients are the same. This means that the effects can be expected.

Effects of the Invention The present invention is an electronic component having a terminal electrode containing a metal phase and an inorganic glass phase, the metal phase being made of copper or nickel alloy containing at least one component of the group consisting of lead, tin, or zinc. Therefore, we have developed a terminal electrode structure that is low cost, has good solderability, has little deterioration in solderability due to oxidation of the element surface, and has an excellent effect of mitigating thermal shock to the element during soldering. An inexpensive and simple manufacturing process and electrode paste are provided.

[Brief explanation of drawings]

FIGS. 1 and 2 are schematic cross-sectional views of the terminal electrode portion of a fixed resistor element according to an embodiment of the present invention, and FIGS. 3 to 7 are respectively a ceramic multilayer capacitor element according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a terminal electrode section of FIG. 11.21.31,41,5L 61.71... Ceramic element body, 12, 22, 32, 42.
52,62.72... Base layer containing inorganic frit, 1
3,7B...Intermediate phase in which copper and lead form a mixed texture phase,
23... Intermediate layer forming a mixed texture phase or solid solution phase of copper and tin, 33... Intermediate layer forming a mixed texture phase or solid solution phase of nickel and lead, 43... Between nickel and tin metal Intermediate layer forming a mixed texture phase or solid solution phase of a compound, 53... Intermediate layer forming a mixed texture phase or solid solution phase of a nickel and zinc intermetallic compound, 63... Intermediate layer forming a mixed texture phase or solid solution phase of a nickel and zinc intermetallic compound. Intermediate layer forming a mixed texture phase or solid solution phase, 14,34.74... surface layer containing a lead metal phase,
24.44...Surface layer consisting of tin metal phase, 54...
Surface layer containing a single zinc metal phase or an intermetallic compound phase with nickel, 64...Surface layer containing a single zinc metal phase or an intermetallic compound phase with copper.

Claims (1)

[Scope of Claims] (1) It has a terminal electrode portion containing a metal phase and an inorganic glass phase, and the metal phase is at least one member of the group consisting of lead, tin, and zinc.
An electronic component characterized by being made of a copper alloy containing the following components. (2) The electronic component according to claim 1, wherein the metal phase contained in the terminal electrode portion is an alloy containing copper and lead, and contains 0.3 wt% or more and 70 wt% or less of lead. (3) The electronic component according to claim 1, wherein the metal phase contained in the terminal electrode portion is an alloy containing copper and tin, and contains 0.8 wt% or more and 65 wt% or less of tin. (4) The electronic component according to claim 1, wherein the metal phase contained in the terminal electrode portion is an alloy containing copper and zinc, and contains zinc in an amount of 0.5 wt% or more and 80 wt% or less. (5) It has a terminal electrode portion containing a metal phase and an inorganic glass phase, and the metal phase is at least one member of the group consisting of lead, tin, and zinc.
An electronic component characterized by being made of a Yuckel alloy containing the following components. 6. The electronic component according to claim 5, wherein the metal phase contained in the (θ) terminal electrode portion is an alloy containing Eckel and lead, and contains 1.5 wt% or more and 45 wt% or less of lead. (7) The electronic component according to claim 5, wherein the metal phase contained in the terminal electrode portion is an alloy containing nickel and tin, and contains 1.5 wt% or more and 55 wt% or less of tin. (8) The electronic component according to claim 5, wherein the metal phase contained in the terminal electrode portion is an alloy containing nickel and zinc, and contains zinc in an amount of 1.5 wt% or more and 65 wt% or less. (9) A dielectric ceramic layer, having an internal electrode layer using a base metal, and an external electrode connected to the internal electrode layer and containing a metal phase, the internal electrodes of the internal electrode layer being arranged alternately in opposing directions. A multilayer capacitor stacked so as to be drawn out, wherein the metal phase included in the external electrode is a copper alloy containing at least one component of the group consisting of lead, tin, and zinc, or at least one component of the group consisting of lead, tin, and zinc. An electronic component characterized by being a nickel alloy containing one component. (10) It has a terminal electrode directly attached to the ceramic body, and the cross section of the terminal electrode is a metal phase mainly composed of copper or nickel, a metal phase mainly composed of lead, zinc, or tin, or a metal phase mainly composed of copper or nickel. , has an intermediate layer of either a mixed texture phase or a solid solution alloy phase containing at least two selected from the group consisting of intermetallic compound phases of lead, zinc, or tin, and further has an average composition higher than that of the intermediate layer. An electronic component characterized by having a surface layer containing a large amount of lead, tin, or zinc. (11) A surface in which the cross section of the terminal electrode part consists of an intermediate layer containing at least a mixed texture phase of a metal phase mainly composed of copper and a metal phase mainly composed of lead, and a partially or entirely composed of a metal lead layer. The electronic component according to claim 10, characterized in that it has a layer. (12) The cross section of the terminal electrode part has a mixed structure of at least two types selected from the group consisting of a metallic phase mainly composed of copper, a metallic phase mainly composed of tin, or an intermetallic compound of copper or tin. or an intermediate layer containing a solid solution metal phase in which at least tin is solidly dissolved in copper, and a surface of either a metal phase whose main component is tin partially or entirely, or a mixed structure phase of an intermetallic compound of copper and tin and tin. Claim 1 characterized in that it has a layer.
Electronic component described in 0. (13) The cross section of the terminal electrode part has a mixed structure of at least two types selected from the group consisting of a metal phase mainly composed of copper, a metal phase mainly composed of zinc, or an intermetallic compound phase of copper or zinc. or an intermediate layer containing a solid solution metal phase in which at least zinc is solidly dissolved in copper, and a surface of either a metal phase whose main component is zinc partially or entirely, or a mixed structure phase of an intermetallic compound of copper and zinc and zinc. The electronic component according to claim 10, characterized in that it has a layer. (14) The cross section of the terminal electrode part is an intermediate structure containing at least either a mixed structure phase of a metal phase mainly composed of nickel and a metal phase mainly composed of lead, or a solid solution metal phase in which lead is dissolved in nickel. 11. The electronic component according to claim 10, further comprising a surface layer partially or entirely made of a metal layer containing lead as a main component. (15) The cross section of the terminal electrode part has a mixed structure of at least two types selected from the group consisting of a metallic phase mainly composed of Yuckel, a metallic phase mainly composed of tin, or an intermetallic compound phase of nickel or tin. Or an intermediate layer containing either a solid solution metal phase in which tin is dissolved in nickel, and a metal phase whose main component is tin partially or entirely, or a mixed structure phase of an intermetallic compound phase of nickel and tin and metallic tin. The electronic component according to claim 10, characterized in that it has any one of the surface layers. (16) The cross section of the terminal electrode part is a mixed structure phase of at least two types selected from the group consisting of a metal phase mainly composed of nickel, a metal phase mainly composed of zinc, or an intermetallic compound of nickel or zinc. An intermediate layer containing either a solid solution metal phase in which at least zinc is solidly dissolved in nickel, and a metal phase whose main component is zinc partially or entirely, or a mixed structure of an intermetallic compound of metal nickel and metal zinc and metal zinc. 11. The electronic component according to claim 10, further comprising a surface layer of any one of the phases. (17) In a terminal electrode paste formed by direct baking on a ceramic body, the metal components in the paste are melted or decomposed and melted together with metal components that do not generate a liquid phase by themselves during the baking process. Contains two types of metal components: either a metal component that generates a liquid phase or a metal component that does not generate a liquid phase alone, and a metal component that generates a liquid phase through a eutectic reaction, and solidification of the liquid phase component that generates. An electrode paste characterized in that the phase contains at least one component selected from the group consisting of lead, zinc, and tin. (18) The metal powder contained in the terminal electrode paste formed by direct baking on the ceramic body is metal powder mainly composed of copper or nickel, metal powder mainly composed of lead, zinc or tin, or copper powder. The electrode paste according to claim 17, characterized in that it contains at least two metal powders or alloy powders selected from metal powders consisting of intermetallic compounds of nickel, lead, zinc, and tin. (19) The electrode paste contains metallic copper powder, metallic lead powder, inorganic frit powder, organic binder, and organic solvent, and the weight ratio of lead in the metal component is 0.3 wt% or more 70w
The electrode paste according to claim 17, characterized in that the content of the electrode paste is t% or less. (20) The electrode paste contains metallic copper powder, metallic tin powder, inorganic frit powder, organic binder, and organic solvent, and the weight ratio of tin in the metal component is 0.8 wt% or more 65w
The electrode paste according to claim 17, characterized in that the content of the electrode paste is t% or less. (21) The electrode paste includes metallic copper powder, metallic zinc powder,
Composed of inorganic frit powder, organic binder and organic solvent, the weight ratio of zinc in the metal component is 0.5wt%
Claim 1 characterized in that the content is 80 wt% or more.
7. Electrode paste according to 7. (22) The electrode paste contains metallic nickel powder, metallic lead powder, inorganic frit powder, organic binder, and organic solvent, and the weight ratio of lead in the metal component is 1.5 wt% or more and 45 wt% or less. , the electrode paste according to claim 17. (23) The electrode paste contains metallic nickel powder, metallic tin powder, inorganic frit powder, organic binder, and organic solvent, and the weight ratio of tin in the metal component is 1.5 wt% or more and 55 wt% or less. , the electrode paste according to claim 17. (24) The electrode paste contains metallic nickel powder, metallic zinc powder, inorganic frit powder, organic binder, and organic solvent, and the weight ratio of zinc in the metal component is 1.5 wt%.
Claim 1 characterized in that the content is 65 wt% or more.
7. Electrode paste according to 7. (25) In a method for forming a terminal electrode by directly baking an electrode paste onto a ceramic body, the electrode paste contains a metal component that does not generate a liquid phase by itself during the baking process, and a metal component that melts or decomposes and melts by itself. The metal component contains two types of metal components: either a metal component that generates a liquid phase through a eutectic reaction or a metal component that does not generate a liquid phase when used alone, and a metal component that generates a liquid phase through a eutectic reaction. An electronic component characterized by being processed at a temperature higher than the temperature at which a liquid phase is partially formed between metals or intermetallic compounds due to the eutectic phenomenon or partial melting of metal powder, intermetallic compound powder, or alloy powder. How to form terminal electrodes. (26) In a method for forming a terminal electrode by directly baking it onto a ceramic body, as a starting material for the electrode metal,
Metal powder mainly composed of copper or nickel, metal powder mainly composed of lead, zinc or tin, or copper, nickel,
A powder consisting of an intermetallic compound powder or an alloy powder of lead, zinc, or tin is used, and during the baking process, the metal powder, the intermetallic compound powder, or the alloy powder partially melts due to the eutectic phenomenon or melting of a part of the powder. 26. The method for forming a terminal electrode according to claim 25, wherein the process is performed at a temperature higher than or equal to a temperature at which a liquid phase is formed between intermetallic compounds.