JPWO2012020694A1 - Glass composition for electrode, electrode paste using the same, and electronic component using the same - Google Patents

Abstract

The glass composition for electrodes of the present invention is characterized by containing silver, phosphorus and oxygen, and substantially free of lead and bismuth. The electrode glass composition preferably contains vanadium or tellurium, and more preferably contains one or more metal elements of barium, tungsten, molybdenum, iron, manganese, and zinc. As a result, in an Ag-based, Al-based or Cu-based electrode formed on an electronic component, an electrode glass composition that does not substantially contain harmful lead or bismuth and does not deteriorate the performance of the electronic component, and The used electrode paste can be provided.

Description

  The present invention relates to a glass composition for an electrode, an electrode paste using the same, and an electronic component to which the same is applied.

  Electrodes such as silver (Ag), aluminum (Al), and copper (Cu) are applied to electronic components such as solar cell elements, image display devices, multilayer capacitors, and multilayer circuit boards. These electrodes are generally used as components of electronic components by applying a paste containing metal particles such as Ag, Al, and Cu, glass particles, resin binder and solvent by a printing method and baking the paste. is there.

The glass particles are mixed in order to improve and secure the sinterability of the metal particles and the adhesion to the base material by softening and flowing during electrode firing. As the glass particles, a glass mainly composed of lead oxide (PbO) having a low transition point that softens and flows at a relatively low temperature is used. However, lead (Pb) contained in the glass is a harmful substance, and in order to reduce the environmental load, electronic components such as solar cell elements and plasma display panels have bismuth oxide (Bi ₂ O ₃ ). Pb-free glass mainly composed of is being applied to electrodes.

  In Europe, the European Union (EU) Directive (RoHS Directive) has been enforced on restrictions on the use of specific hazardous substances in electrical and electronic equipment products.

For example, in Patent Document 1, Pb-free glass containing Bi ₂ O ₃ and silicon oxide (SiO ₂ ) in an Ag electrode and an Al electrode formed in a solar cell element, and in Patent Document 2, Al formed in a solar cell element. Pb-free glass containing Bi ₂ O ₃ and boron oxide (B ₂ O ₃ ) as an electrode has been proposed.

Further, Patent Documents 3 and 4 propose a glass mainly composed of vanadium oxide (V ₂ O ₅ ) for an Ag electrode formed on an electronic component such as a plasma display panel or a multilayer capacitor. These glasses do not contain Bi in addition to Pb. The glass described in Patent Document 3 is composed of V ₂ O ₅ , phosphorus oxide (P ₂ O ₅ ), antimony oxide (Sb ₂ O ₃ ), and barium oxide (BaO). The glass is composed of V ₂ O ₅ , P ₂ O ₅ , BaO and sodium oxide (Na ₂ O).

  Furthermore, in the Joint Industry Guideline (JIG), Pb, Bi, and the like are substances to be investigated (see Non-Patent Document 1).

JP 2008-543080 A JP 2006-332032 A JP 2008-251324 A JP-A-8-138969

Disclosure of information on chemical substances contained in electrical and electronic equipment products http://210.254.215.73/jeita_eps/green/greendata/JIG200601/JIG_Japanese060105.pdf

As in Patent Documents 1 and 2, Pb-free glass mainly composed of Bi ₂ O ₃ is used in electronic parts in place of glass mainly composed of PbO which is harmful as an electrode glass composition in consideration of environmental load. Has come to be used. However, since Bi is mined in small quantities as a byproduct of Pb, the extraction of Bi leads to the release of a large amount of Pb. Moreover, Pb waste is also generated in the purification of Bi. Therefore, the adoption and application of Bi for electronic components are not sufficiently considered to reduce the environmental load.

  In addition, since Bi has a small reserve and is unevenly distributed on the earth, there is a concern from the viewpoint of securing stable raw materials.

Furthermore, when glass containing Bi ₂ O ₃ as a main component is used in combination with metal particles of Al or Cu, metal Bi may be precipitated. In this case, the temperature of the glass increases, which may hinder the sintering of the metal particles and the adhesion to the substrate. Further, in the electronic component such as a silicon solar cell element, the Ag electrode of the element receiving surface, it is necessary to connect the silicon substrate and electrically through the anti-reflection film such as a silicon nitride film, a Bi ₂ O ₃ An Ag electrode containing glass as a main component has a problem that the reactivity between the glass and the antireflection film is insufficient, and proper electrical connection with the silicon substrate cannot be obtained, resulting in a decrease in conversion efficiency. . For this reason, there are still very many examples in which glass containing PbO as a main component is still applied to the light receiving surface Ag electrode of the silicon solar cell element.

On the other hand, Patent Documents 3 and 4 propose a glass composition for Ag electrodes that contains Pb and Bi and contains V ₂ O ₅ as a main component. However, since the reactivity with Ag metal particles is not sufficiently considered, the electrical resistance as an electrode tends to increase more than when glass containing PbO as a main component is applied due to the reaction. It is difficult to bring out the performance of the electronic components used. As a countermeasure for this, there is a method of increasing the film thickness of the electrode, but this causes problems such as an increase in manufacturing cost of the electronic component.

  An object of the present invention is to provide a glass composition for an electrode that does not substantially contain Pb or Bi and does not deteriorate the performance of the electronic component, an electrode paste using the same, and an electronic component to which the same is applied. It is in.

  In the present invention, the glass composition for electrodes contains silver, phosphorus and oxygen, and is substantially free of lead.

  According to the present invention, Ag-based, Al-based, Cu-based, etc. electrodes formed on electronic parts do not contain substantially harmful Pb and Bi produced together with the Pb, and the performance of the electronic parts is reduced. It is possible to provide a glass composition for an electrode that is not allowed, and an electrode paste using the same. Thereby, it is possible to provide electronic components such as a solar cell element, an image display device, a multilayer capacitor, and a multilayer circuit board on which electrodes are formed.

It is a graph which shows the relationship between the calcination temperature of Ag type electrode, and a specific resistance. It is a SEM image at the time of producing by baking the Ag type electrode of an Example at 700 degreeC. It is a SEM image at the time of producing by baking the Ag type electrode of an Example at 700 degreeC. It is a graph which shows the relationship between the glass content in an Ag type electrode, and a specific resistance. It is a graph which shows the relationship between the calcination temperature of Al type electrode, and a specific resistance. It is a cross-sectional SEM image at the time of producing by baking the Ag type electrode of an Example at 800 degreeC. It is a cross-sectional SEM image at the time of producing by baking the Ag type electrode of an Example at 800 degreeC. It is a graph which shows the relationship between the glass content in an Al-type electrode, and a specific resistance. It is a graph which shows the relationship between the firing temperature and specific resistance of an AlCu alloy-type electrode. It is a graph which shows the relationship between the glass content and specific resistance in an AlCu alloy-type electrode. It is a graph which shows the relationship between the baking temperature and specific resistance of a Cu-type electrode. It is a graph which shows the relationship between the glass content in a Cu-type electrode, and a specific resistance. It is sectional drawing which shows the structure of a typical solar cell element. It is a top view which shows the light-receiving surface of a typical solar cell element. It is a bottom view which shows the structure of a typical solar cell element. It is sectional drawing which shows the structure of a typical plasma display panel. It is sectional drawing which shows the structure of a typical multilayer circuit board. It is sectional drawing which shows the structure of a typical multilayer capacitor. It is a DTA curve of typical glass. It is a graph which shows the relationship between the glass content in an Al-type electrode, and a specific resistance.

  The present inventor, in an electrode containing at least a metal and a glass composition, when the glass composition substantially does not contain Pb and contains at least Ag, P and O, the performance of the electronic component on which the electrode is formed It was found that the impact on the environmental load can be reduced without lowering. Here, it is desirable that the glass composition does not contain Bi.

  As the metal of the electrode, Ag-based, Al-based and Cu-based materials, ie, electrode materials mainly composed of Ag, Al or Cu were confirmed.

  Typical examples of this electronic component include a solar cell element, an image display device, a multilayer capacitor, a multilayer circuit board, and the like.

  Hereinafter, the glass composition for electrodes which concerns on one Embodiment of this invention, the paste for electrodes using the same, and the electronic component formed using this are demonstrated.

  The electrode glass composition is contained in an electrode or electrode paste containing a metal, and contains silver (Ag), phosphorus (P) and oxygen (O), and substantially contains lead (Pb) and It does not contain bismuth (Bi). Here, “substantially not including Pb and Bi” is synonymous with not reaching the threshold level described in Non-Patent Document 1. That is, in the present invention, when the content is less than the threshold level, it is accepted as “substantially not contained”.

  The glass composition for an electrode preferably further contains vanadium (V).

  The glass composition for an electrode preferably further contains tellurium (Te).

  The electrode glass composition further includes at least one metal selected from the group consisting of barium (Ba), tungsten (W), molybdenum (Mo), iron (Fe), manganese (Mn), and zinc (Zn). It is desirable to include an element.

Also, the preferred composition range of the electrode glass composition, in terms of oxide, Ag ₂ O 5 to 60 wt%, P ₂ O ₅ is 5 to 50 wt%, V ₂ O ₅ is 0 to 50 wt% TeO ₂ is 0 to 30% by weight and other oxides are 0 to 40% by weight, and the total of Ag ₂ O and V ₂ O ₅ is 30 to 86% by weight, and P ₂ O ₅ and TeO The sum of ₂ is 14 to 50% by weight. The other oxide is at least one selected from the group consisting of BaO, WO ₃ , MoO ₃ , Fe ₂ O ₃ , MnO ₂ and ZnO.

A more preferable composition range of the glass composition for electrodes is 40 to 70% by weight of Ag ₂ O + V ₂ O ₅ (composition of Ag ₂ O and V ₂ O ₅ ) in terms of oxide, provided that Ag ₂ O is 10 to 50% by weight, V ₂ O ₅ is 20 to 50% by weight, P ₂ O ₅ + TeO ₂ (composition of P ₂ O ₅ and TeO ₂ ) is 25 to 50% by weight, provided that P ₂ 10 to 30% by weight of O _5, 0 to 30% by weight of TeO ₂ , 0 to 30% by weight of BaO + WO ₃ + Fe ₂ O ₃ + ZnO (composition of BaO, WO ₃ , Fe ₂ O ₃ and ZnO) However, BaO is 0 to 20 wt%, WO ₃ is 0 to 10 wt%, Fe ₂ O ₃ is 0 to 10 wt%, and ZnO is 0 to 15 wt%.

  Furthermore, the transition point of the glass composition for an electrode is 392 ° C. or lower, preferably 310 ° C. or lower.

  The electrode glass composition can be effectively applied to an electrode containing one or more metal elements selected from the group consisting of silver (Ag), copper (Cu), and aluminum (Al).

  The electrode paste includes metal particles containing one or more metal elements of Ag, Al, and Cu, particles of the electrode glass composition, a resin binder, and a solvent.

  The electrode paste preferably includes 0.2 to 20 parts by weight of electrode glass particles with respect to 100 parts by weight of metal particles.

  Further, when the metal particles are Ag particles or particles containing Ag as a main component, it is effective that the amount of the electrode glass particles is 3 to 15 parts by weight with respect to 100 parts by weight of the metal particles.

  When the metal particles are Al particles or particles containing Al as a main component, it is effective that the electrode glass particles are 0.2 to 20 parts by weight with respect to 100 parts by weight of the metal particles.

  When the metal particles are Cu particles or Cu-based particles, it is effective that the electrode glass particles are 3 to 15 parts by weight with respect to 100 parts by weight of the metal particles.

  In the electrode paste, it is preferable to apply ethyl cellulose or nitrocellulose as the resin binder and butyl carbitol acetate or α-terpineol as the solvent.

  The electronic component includes an electrode formed by applying the electrode paste to a substrate or the like and baking it. Here, the electrode after baking contains the metal derived from a metal particle, and the glass composition for electrodes. The resin binder and the solvent are hardly left because they are vaporized by firing. Therefore, the main component of the metal conductor contained in the electrode after firing is Ag in the Ag-based electrode, Al in the Al-based electrode, and Cu in the Cu-based electrode.

  It is preferable that the glass composition for electrodes contained in the electrode formed in this electronic component is 0.1-30 volume%. In particular, when the electrode is an Ag-based electrode, it is effective that the electrode glass composition contained in the electrode is 5 to 30% by volume. In the case of an Al-based electrode, it is effective that the electrode glass composition contained in the electrode is 0.1 to 15% by volume. In the case of a Cu-based electrode, it is effective that the electrode glass composition contained in the electrode is 5 to 20% by volume.

  Moreover, as said electronic component, a solar cell element, an image display device, a multilayer capacitor, or a multilayer circuit board is mentioned. In particular, the present invention is effective in the case of a solar cell element using a silicon substrate.

In the solar cell element as the electronic component, the glass composition contained in the Al-based electrode of the back surface collecting electrode formed on the p-type upper part is preferably a conductive glass containing a transition metal and P. It is effective that the transition metal in the conductive glass exists in a plurality of oxidation number states, and the existence ratio of the element exhibiting the highest oxidation number state in the transition metal satisfies the relationship of the following formula (1).

Here, the left side of the formula (1) is defined as the ion fraction. This ion fraction is determined by pentavalent vanadium (V ⁵⁺ ), hexavalent tungsten (W ⁶⁺ ), hexavalent molybdenum (Mo ⁶⁺ ), and trivalent iron (Fe ³⁺ ) obtained by each measurement. And the sum of the concentrations of tetravalent manganese (Mn ⁴⁺ ) divided by the sum of the concentrations of vanadium, tungsten, molybdenum, iron, and manganese in the measurement sample, each transition metal exhibits the highest oxidation number state. It is the ratio of existing elements.

  In the above formula (1), {} means the concentration of ions or atoms in parentheses (unit: mol / L).

Furthermore, the conductive glass contained in the Al-based electrode does not contain any prohibited substances of the RoHS directive, contains V and P as main components, and the mass ratio in terms of oxide of the contained components is expressed by the following formula (2) It is preferable to satisfy the relationship.

  Here, [] means a mass ratio (unit: mass%) converted to an oxide in parentheses.

  In particular, it is effective that the conductive glass composition contained in the Al-based electrode is 0.1 to 5% by volume.

  The electrode paste includes conductive glass particles containing Al and P, Al-based particles, a binder resin, and a solvent. The transition metal in the conductive glass particles is present in a plurality of oxidation number states, and it is desirable that the abundance ratio of the element exhibiting the highest oxidation number state in the transition metal satisfies the relationship of the above formula (1).

  Furthermore, the electrode paste includes conductive glass particles, metal particles, a binder resin, and a solvent, does not include a RoHS directive prohibited substance, the conductive glass particles include V and P as main components, and It is effective that the mass ratio in terms of oxide of the contained component satisfies the relationship of the above formula (2).

  Further, the solar cell element is characterized in that the back surface output extraction electrode includes a glass composition containing Ag, P and O, which is the glass composition described above, and substantially free of Pb and Bi. It is made of paste. The back surface collecting electrode contains a transition metal and P of the glass composition described later, and this transition metal exists in a plurality of oxidation number states, and the abundance ratio of the elements exhibiting the highest oxidation number state in the transition metal Is preferably formed of an electrode paste containing a conductive glass composition satisfying the relationship of the above formula (1).

  As a component of the glass composition contained in the electrode, it was found that V was also effective in addition to Ag, P and O. It has been found that V contained in the glass composition has a function of lowering the firing temperature when forming an electrode on an electronic component, and can improve the moisture resistance, that is, the corrosion resistance of the Al-based electrode. It was also found that Te is preferable as a component of the glass composition although it is a scarce resource and expensive. Te contained in the glass composition, like V, has a function of lowering the firing temperature in forming electrodes on electronic components. In addition to V and Te, it is desirable to include one or more of Ba, W, Mo, Fe, Mn, and Zn, which has been found to contribute to the improvement of electrode reliability, particularly moisture resistance.

Preferred glass composition range, in terms of oxide, Ag ₂ O 5 to 60 wt%, P ₂ O ₅ is 5 to 50 wt%, V ₂ O ₅ is 0 to 50 wt%, TeO ₂ 0 to 30 weight %, And other oxides are 0 to 40% by weight. Furthermore, it was found that the total of Ag ₂ O and V ₂ O ₅ is preferably 30 to 86% by weight, and the total of P ₂ O ₅ and TeO ₂ is preferably 14 to 50% by weight.

Examples of other oxides include BaO, WO ₃ , MoO ₃ , Fe ₂ O ₃ , MnO ₂ , ZnO and the like, and it was effective to include one or more of them.

When Ag ₂ O is less than 5% by weight, there is a tendency that the electric resistance of the Ag-based electrode and the Cu-based electrode is increased and the moisture resistance of these electrodes is decreased. On the other hand, when Ag ₂ O exceeds 60% by weight, the glass composition is costly and the water resistance of the electrode tends to decrease.

When P ₂ O ₅ is less than 5% by weight, it is difficult to form a glass composition, while when P ₂ O ₅ exceeds 50% by weight, the moisture resistance of the electrode is lowered. When V ₂ O ₅ exceeds 50% by weight, the electric resistance of the Ag-based electrode and the Cu-based electrode tends to increase, and the moisture resistance of these electrodes tends to decrease.

It has been found that when TeO ₂ exceeds 30% by weight, the glass composition increases in cost and the volatilization of the glass component increases during glass production. If the other oxide exceeds 40% by weight, the glass composition may crystallize remarkably, or its softening fluidity may increase remarkably.

Furthermore, when the total of Ag ₂ O and V ₂ O ₅ is less than 30% by weight, the softening fluidity of the glass composition is increased in temperature, and the adhesion between the Ag-based electrode and the Cu-based electrode is lowered. On the other hand, when the total of Ag ₂ O and V ₂ O ₅ exceeds 86% by weight, the glass composition is easily crystallized, and the moisture resistance of the Ag-based electrode and the Cu-based electrode is lowered.

When the total of P ₂ O ₅ and TeO ₂ was less than 14% by weight, crystallization of the glass composition occurred remarkably, and handling in glass crushing and electrode formation was not easy. On the other hand, when the total of P ₂ O ₅ and TeO ₂ exceeded 50% by weight, the moisture resistance of the electrode was lowered.

A particularly good glass composition range is 40 to 70% by weight of Ag ₂ O + V ₂ O ₅ (composition of Ag ₂ O and V ₂ O ₅ ) in terms of the following oxides, provided that Ag ₂ O is 10%. 50 wt%, V ₂ O ₅ is 20-50 wt%, P ₂ O ₅ + TeO ₂ (P ₂ O ₅ and TeO ₂ and composition combined) is 25 to 50 wt%, provided that the P ₂ O ₅ 10-30 wt%, TeO ₂ 0-30 wt%, BaO + WO ₃ + Fe ₂ O ₃ + ZnO (combination of BaO, WO ₃ , Fe ₂ O ₃ and ZnO) 0-30 wt%, but BaO Was 0 to 20% by weight, WO ₃ was 0 to 10% by weight, Fe ₂ O ₃ was 0 to 10% by weight, and ZnO was 0 to 15% by weight. Further, the transition point of the glass composition is preferably 392 ° C. or less, and if it exceeds this, the adhesion of the electrode may be lowered. In particular, the adhesion of the glass composition having a transition point of 310 ° C. or lower was good.

  The electrode is coated, dried, and fired using an electrode paste containing metal particles containing any one or more of Ag, Al, and Cu, particles of the glass composition, a resin binder, and a solvent. Thus, an electronic component was produced.

  As a glass composition, ethyl cellulose or nitrocellulose is effective as a resin binder, butyl carbitol acetate or α-terpineol is effective as a solvent, and particles of the glass composition are corroded in an electrode paste. There was hardly anything. When the glass composition particles are corroded by a resin binder or solvent, good adhesion may not be obtained during electrode formation.

  From the viewpoint of electrical resistance, adhesion and moisture resistance as an electrode, it is effective that the range of 0.2 to 20 parts by weight of the particles of the glass composition of the present invention is 100 parts by weight of the metal particles in the electrode paste. all right. When the glass composition was less than 0.2 parts by weight, good adhesion could not be obtained. On the other hand, when the glass composition exceeds 20 parts by weight, a tendency that the electric resistance is remarkably increased is recognized. Particularly, in the case of the Ag-based electrode paste, the range of 3 to 15 parts by weight of the glass composition particles of the present invention was effective with respect to 100 parts by weight of the Ag-based metal particles. In the Al-based electrode paste, the range of 0.2 to 20 parts by weight of the glass composition particles of the present invention was effective with respect to 100 parts by weight of the Al-based metal particles. In the Cu-based electrode paste, the range of 3 to 15 parts by weight of the glass composition particles of the present invention was effective with respect to 100 parts by weight of the Cu-based metal particles.

  Moreover, in the electronic component which formed the electrode by apply | coating using said electrode paste and baking, 0.1-30 volume% is effective for the ratio of the glass composition in the electrode. If the ratio is less than 0.1% by volume, good adhesion cannot be obtained. On the other hand, when the ratio exceeded 30% by volume, the electric resistance tended to increase remarkably. In particular, for an Ag-based electrode, a glass composition ratio of 5 to 30% by volume is effective, for an Al-based electrode, a glass composition ratio of 0.1 to 15% by volume is effective, and for a Cu-based electrode, glass A composition ratio of 5-20% by volume was effective. It was found that the effective electrode can be applied to electronic parts such as a solar cell element, an image display device, a multilayer capacitor, and a multilayer circuit board without any problem. In particular, it was effective for solar cells using a silicon substrate.

  In the solar cell element, the glass composition contained in the electrode of the Al-based electrode of the back surface collecting electrode formed on the p-type upper part is a conductive glass containing a transition metal and P. The transition metal in the conductive glass is present in a plurality of oxidation number states, and a glass composition in which the abundance ratio of elements exhibiting the highest oxidation number state in the transition metal satisfies the relationship of the above formula (1) is applied. In this case, it was found that the moisture resistance of the Al-based electrode was remarkably improved and the reliability as a solar cell element was improved.

  In particular, the conductive glass contained in the Al-based electrode does not contain any prohibited substances of the RoHS directive, contains V and P as main components, and the mass ratio in terms of oxide of the contained components is the above formula (2). It was found to be effective when satisfying the relationship. Furthermore, it was found that 0.1 to 5% by volume of the conductive glass composition is effective. When the conductive glass composition was less than 0.1%, good adhesion could not be obtained, and when the conductive glass composition was 5% by volume or more, the specific resistance of the electrode as a solar cell increased.

  Moreover, the back surface collecting electrode paste formed on the p-type upper part is an electrode paste containing conductive glass particles containing Al and transition metals and P, Al-based particles, a binder resin, and a solvent. Similarly, when the transition metal in the conductive glass particles exists in a plurality of oxidation number states and the abundance ratio of the element exhibiting the highest oxidation number state in the transition metal satisfies the relationship of the above formula (1). Reliability as a solar cell element is improved.

  In particular, the electrode paste includes conductive glass particles, metal particles, a binder resin, and a solvent, and does not include any RoHS prohibited substances. The conductive glass particles include V and P as main components, and It is effective that the mass ratio in terms of oxide of the contained component satisfies the relationship of the above formula (2).

  Further, the back surface output extraction electrode of the solar cell element includes a glass composition containing Ag, P and O, which is the glass composition described above, and substantially free of Pb and Bi. The back surface collecting electrode contains a transition metal and P, which are glass compositions described later, and the transition metal in the conductive glass exists in a plurality of oxidation number states, and has the highest oxidation number among the transition metals. When formed with an electrode paste containing an electrically conductive glass composition that satisfies the relationship of the above formula (1), the presence ratio of the element presenting the state is effective without causing discoloration of the solar cell element. It was.

  Details will be described below using typical examples.

  Table 1 shows the composition of glass, its transition point and softening fluidity.

  The glass of G1-G37 is the glass of the Example which does not contain Bi produced with Pb and Pb which are substantially harmful | toxic, but contains Ag, P, and O at least. On the other hand, the glass of G38-G41 is a glass of a comparative example.

G38 is a glass having a very large amount of V ₂ O ₅ of 55% by weight and a small amount of Ag ₂ O. G38 is a glass containing V ₂ O ₅ as a main component and not containing Ag ₂ O. G40 is a glass mainly composed of PbO. G41 is a glass mainly composed of Bi ₂ O ₃ . Commercially available G40 and G41 glasses were used. On the other hand, the glass of G1-G39 was produced by itself.

The production method is as follows: Ag ₂ O, P ₂ O ₅ , V ₂ O ₅ , TeO ₂ , BaCO ₃ , WO ₃ , MoO ₃ , Fe ₂ O ₃ , MnO ₂ and ZnO are used as glass materials, and the glass composition shown in Table 1 is used. A total of about 200 g was prepared and mixed. This was put into a crucible and melted at 800 to 1000 ° C. for 1 hour. Meanwhile, the mixture was stirred to obtain a uniform composition. The melt in the crucible was poured onto a stainless plate to produce glass.

  The glass was crushed and evaluated for transition point (Tg) and softening fluidity. Tg was measured by differential thermal analysis (DTA). For softening fluidity, a thick powder molded body having a diameter of 10 mm and a thickness of 5 mm was prepared, placed in an electric furnace maintained at 600 ° C., 700 ° C., and 800 ° C. in the air, and held for 5 minutes. The condition was evaluated. ○ when good fluidity is obtained, good fluidity is obtained, but ● when crystallization or surface devitrification is observed, softening, but fluidity is insufficient Was evaluated as Δ, and when not softened, it was evaluated as ×.

  Since Tg of G34, G37 and G41 is as high as 400 ° C. or higher, the fluidity at 600 ° C. was insufficient. However, good fluidity was exhibited at 700 ° C and 800 ° C. Other glasses had low Tg and good fluidity at 600-800 ° C. However, crystallization or surface devitrification occurred for G7, G8, G12, G22 and G33.

Next, an electrode paste was prepared using Ag particles, particles of the glass composition shown in Table 1, a resin binder, and a solvent. Spherical particles with an average particle size of 1.4 μm are used as Ag particles, pulverized powder with an average particle size of 3.0 μm or less is used as glass composition particles, ethyl cellulose is used as a resin binder, and butyl carbitol acetate is used as a solvent. It was. The content of the glass composition particles was 5 parts by weight with respect to 100 parts by weight of the Ag particles. Moreover, content of paste solid content containing Ag particle | grains and glass composition particle | grains was 70 to 75 weight%. Using the produced Ag-based electrode paste, it was applied to an alumina (Al ₂ O ₃ ) substrate at a 20 mm square by a printing method.

  The coating thickness after drying at 150 ° C. was around 20 μm. After drying at 150 ° C, put it in an electric furnace held at 600 ° C, 700 ° C and 800 ° C in the air, hold it for 5 minutes, take it out, and check the electric resistance, adhesion and moisture resistance of the Ag-based electrode after firing evaluated.

For electrical resistance, the specific resistance at room temperature was measured by the four probe method. When the specific resistance was in the range of 10 ⁻⁶ Ωcm, it was evaluated as ◎, when it was in the range of 10 ⁻⁵ Ωcm, Δ when it was in the range of 10 ⁻⁴ Ωcm, and × when it was in the range of 10 ⁻³ Ωcm or more.

  Adhesiveness was evaluated as ◯ when the Ag-based electrode was not peeled off when the peeling tape was applied and peeled off, Δ when partially peeled, and × when almost peeled off.

  As for moisture resistance, a high-temperature and high-humidity test at 85 ° C and 85% was performed for 1000 hours. When there was almost no change in the Ag-based electrode, ○ was observed when partial corrosion was observed, and corrosion was observed on the entire surface. If it was observed or peeling was observed, it was evaluated as x.

  Table 2 summarizes the evaluation results of the electrical resistance, adhesion and moisture resistance of Ag-based electrodes.

From this table, it can be seen that the Ag-based electrodes of Comparative Examples AG40 and AG41 using the conventional glass compositions G40 and G41 mainly composed of PbO or Bi ₂ O ₃ exhibit almost good electrical resistance and adhesion. . However, due to the high transition point of G41, firing of AG41 at 600 ° C. did not proceed sufficiently, and the electrical resistance was high. For this reason, the adhesion at 600 ° C. was not sufficient. On the other hand, since the moisture resistance of G41 itself is good, the moisture resistance was also good in the Ag-based electrode AG41 using the glass composition. However, G40 cannot be said to be a glass with good moisture resistance, and the moisture resistance of the Ag-based electrode AG40 containing it cannot be said to be sufficiently good.

  In contrast to the Ag-based electrodes of Comparative Examples AG40 and AG41, the Ag-based electrodes of Examples AG1 to AG37 using the glass compositions G1 to G37 do not contain Bi produced together with harmful Pb and Pb, and are equivalent. Excellent electrical resistance, adhesion and moisture resistance were achieved. In AG34 and AG37 Ag-based electrodes using G34 and G37 glasses having high transition points, it was not possible to say that the electrical resistance and adhesion at 600 ° C. were good as in Comparative Example AG41. This is because the firing of the Ag-based electrode does not proceed sufficiently at 600 ° C., and the Ag-based electrode of the example using the glass composition having a transition point of 392 ° C. or lower has good electrical resistance and adhesion. Had. In addition, the AG31, AG32, AG35, and AG36 Ag-based electrodes exhibited high electrical resistance when fired at a high temperature of 700 ° C. or 800 ° C. This is presumably because the glass compositions of G31, G32, G35 and G36 increase in resistance by reacting with the Ag particles when these glass compositions are baked at 700 ° C. or higher or 800 ° C. or higher. Furthermore, it cannot be said that the water resistance of Ag-based electrodes of AG1, AG2, AG4, AG5, AG9 to AG14 and AG21 is good, as in the case of Comparative Example AG40. That is, the glass compositions of G1, G2, G4, G5, G9 to G14, and G21 were not sufficiently good in water resistance like the glass composition of G40.

  The Ag-based electrodes of Examples AG1 to AG37 described above include glass compositions of G1 to G37. The common point of these glass compositions is that they contain substantially no harmful Pb and Bi and contain at least Ag, P and O.

  More preferably, it contains V and / or Te, or one or more of Ba, W, Mo, Fe, Mn and Zn. This improves the water resistance of the Ag-based electrode.

In the Ag-based electrode of Comparative Example AG39 containing the glass composition G39 not containing Ag ₂ O, the adhesion and moisture resistance were the same as those of Comparative Example AG40, but the electrical resistance was very large and could not be applied to the electrode. There wasn't. This is presumably because the glass composition of G39 is a V ₂ O ₅ —P ₂ O ₅ system that does not contain Ag ₂ O, so that it reacts with the Ag particles and the resistance is remarkably increased. Further, in the Ag-based electrode of Comparative Example AG38 using a glass composition G38 having a small amount of Ag ₂ O and a large amount of V ₂ O ₅ , G38 reacts with Ag particles, although not as much as Comparative Example AG39. The resistance was increased.

  FIG. 1 shows the relationship between firing temperature and specific resistance for Ag-based electrodes of representative examples AG4, AG6, AG16, AG20 and AG26 and comparative examples AG40 and AG41.

In the Ag-based electrode of Comparative Example AG40 using the glass composition G40 containing PbO as a main component, the resistance is lowered almost stably in the temperature range of 600 to 800 ° C. As described above, the Ag-based electrode of Comparative Example AG41 using the glass composition G41 mainly composed of Bi ₂ O ₃ has a slightly higher resistance at 600 ° C., but is almost the same as Comparative Example AG40 at 700 ° C. or higher. It shows an equivalent specific resistance. The Ag-based electrode of Example AG20 using a glass composition of G20 shows almost the same specific resistance as Comparative Example AG40, but Examples AG4 using the glass compositions of G4, G6, G16 and G26, AG6, AG16, and AG26 Ag-based electrodes had a slightly lower resistance than those.

  In order to investigate this cause, the Ag-based electrode was polished, and the firing state was observed with a scanning electron microscope (SEM).

  2A and 2B show SEM images when the Ag-based electrode of Example AG16 was baked at 700 ° C. as a representative example.

  In these drawings, reference numeral 1 denotes Ag sintered particles, and reference numeral 2 denotes a glass composition for electrodes. Ag particles and their electrodes were densely sintered, and as shown in FIG. 2B, many Ag fine particles 3 were precipitated in the electrode glass composition 2. This is considered to be a result of lower resistance than Comparative Examples AG40 and AG41.

The glass compositions of G40 and G41 used in Comparative Examples AG40 and AG41 are insulators. Ag fine particles 3 were observed in the glass composition 2 from any of the Ag-based electrodes of Examples AG4, AG6, AG16, AG20, and AG26, but only Example AG20 had a small amount of precipitation. Therefore, it is considered that the specific resistance was almost the same as that of Comparative Example AG40. The Ag fine particles 3 in the glass composition _{2 have a} larger amount of Ag ₂ O contained in the glass composition, and the lower the transition point, the more the amount of precipitation tends to be. The transition point is 310 ° C. or lower. I liked it.

From the above study results, the preferred composition range as the electrode for the glass composition is the following terms of oxide, Ag ₂ O 5 to 60 wt%, P ₂ O ₅ is 5 to 50% by weight, V ₂ O ₅ 0 to 50 wt%, TeO ₂ is 0 to 30 wt%, other oxides are 0 to 40 wt%, and the total of Ag ₂ O and V ₂ O ₅ is 30 to 86 wt%, P ₂ The sum of O ₅ and TeO ₂ was 14-50% by weight. Examples of other oxides include BaO, WO ₃ , MoO ₃ , Fe ₂ O ₃ , MnO ₂ , and ZnO in the following oxide states, and it is effective to include one or more of them. As a more preferable composition range, Ag ₂ O + V ₂ O ₅ (composition of Ag ₂ O and V ₂ O ₅ ) is 40 to 70% by weight in terms of the following oxide, however, Ag ₂ O is 10%. 50 wt%, V ₂ O ₅ is 20-50 wt%, P ₂ O ₅ + TeO ₂ (P ₂ O ₅ and TeO ₂ and composition combined) is 25 to 50 wt%, provided that the P ₂ O ₅ 10-30 wt%, TeO ₂ 0-30 wt%, BaO + WO ₃ + Fe ₂ O ₃ + ZnO (combination of BaO, WO ₃ , Fe ₂ O ₃ and ZnO) 0-30 wt%, but BaO Was 0 to 20% by weight, WO ₃ was 0 to 10% by weight, Fe ₂ O ₃ was 0 to 10% by weight, and ZnO was 0 to 15% by weight. Further, the transition point of the glass composition is preferably 392 ° C. or lower, more preferably 310 ° C. or lower.

  Next, the content of the glass composition for electrodes of G16 was examined.

  In the same manner as in Example 1, Ag-based electrode pastes were prepared using spherical Ag particles having an average particle size of 1.4 μm as metal particles, ethyl cellulose as a resin binder, and butyl carbitol acetate as a solvent. In addition, pulverized powder having an average particle size of 3.0 μm or less was used for the glass composition of G16.

The content of the glass composition particles is in the range of 3 to 35 parts by weight with respect to 100 parts by weight of the Ag particles, and the content of the paste solid content including the Ag particles and the glass composition particles is 70 to 75% by weight. . Using the produced Ag-based electrode paste, it was applied to an alumina (Al ₂ O ₃ ) substrate at a 20 mm square by a printing method. The coating thickness after drying at 150 ° C. was around 20 μm. After drying at 150 ° C., it was placed in an electric furnace maintained at 600 ° C., 700 ° C. and 800 ° C. in the air, held for 5 minutes, taken out, and the electrical resistance of the Ag-based electrode after firing was measured.

  FIG. 3 shows the relationship between the G16 glass content in the Ag-based electrode and the specific resistance of the Ag-based electrode.

The specific resistance of the Ag-based electrode tended to increase as the glass content increased, but the increase in specific resistance was small up to 15 parts by weight and was as good as 10 ^-6 Ωcm. Beyond that content, the resistivity increased by an order of magnitude. Further, when the glass content was low, the influence of the firing temperature on the specific resistance was small, but when the glass content was increased, the specific resistance tended to increase as the firing temperature increased. This is considered to be that the resistance was increased by the reaction between the glass composition of G16 and Ag particles.

  In this example, the minimum glass content was 3 parts by weight. However, since good electrical resistance and adhesion were obtained, there is a possibility that the glass content can be further reduced. However, if the glass composition is 3 to 15 parts by weight, there is no doubt that it is in a range that can be sufficiently applied as an electrode. Moreover, this range corresponded to 5-30 volume% as a glass composition in an Ag type electrode.

  In the same manner as in Example 1, an Al electrode paste was prepared using Al particles, glass composition particles shown in Table 1, a resin binder, and a solvent. Spherical particles having an average particle diameter of 4 μm were used as Al particles, pulverized powder having an average particle diameter of 3.0 μm or less was used as glass composition particles, ethyl cellulose was used as a resin binder, and α-terpineol was used as a solvent. The content of the glass composition particles was 10 parts by weight with respect to 100 parts by weight of the Al particles. Moreover, content of paste solid content containing Al particle | grains and glass composition particle | grains was 70 to 75 weight%.

  Using the produced Al-based electrode paste, it was applied to a silicon (Si) substrate at a 20 mm square by a printing method. The coating thickness after drying at 150 ° C. was around 200 μm. After drying at 150 ° C, put it in an electric furnace held at 600 ° C, 700 ° C and 800 ° C in the air, hold it for 5 minutes, take it out, and check the electric resistance, adhesion and moisture resistance of the Al electrode after firing Evaluation was performed in the same manner as in Example 1.

  Table 3 summarizes the evaluation results of the electrical resistance, adhesion and moisture resistance of the Al-based electrode formed on the Si substrate.

  Not limited to Examples and Comparative Examples, Al particles were not sintered at 600 ° C., and good electrical resistance and adhesion could not be obtained. Further, when the firing temperature was increased to 700 ° C. and 800 ° C., the sintering of Al particles proceeded, the electrical resistance was reduced, and the adhesion was improved. Also about this, the difference of the influence by a glass composition was hardly recognized. However, regarding the moisture resistance of the Al electrode, a difference in the glass composition was clearly recognized.

Comparative Example AL40 and AL41 Al-based electrodes using conventional glass compositions G40 and G41 mainly composed of PbO or Bi ₂ O ₃ are corroded by water in the high-temperature and high-humidity test and become black, and have sufficient moisture resistance. It could not be said to have sex. In contrast, the Al-based electrodes of Examples AL1 to AL37 and Comparative Examples AL38 and AL39, which do not contain harmful Pb and Bi produced with the Pb, had equivalent or higher moisture resistance. In particular, when a glass composition containing V ₂ O ₅ was used, the moisture resistance was good. This is because V in the glass composition reacts with Al particles, and a layer that is not easily corroded by water is formed on the surface of the Al particles.

  Using the Al-based electrodes of representative examples AL6, AL20, AL26 and AL31 and comparative examples AL40 and AL41, the change in specific resistance depending on the firing temperature was examined in detail.

  FIG. 4 shows the examination results.

  As described above, there was almost no difference in the specific resistance of the Al-based electrode due to the glass composition, and the resistance decreased as the firing temperature increased.

  5A and 5B show cross-sectional SEM images of the Al-based electrode of Example AL31 produced by firing at 800 ° C. FIG.

  In these drawings, reference numeral 4 denotes Al particles, reference numeral 5 denotes a Si substrate, and reference numeral 6 denotes an alloy layer (alloy layer formed by a reaction between Al and Si). Unlike the glass compositions G40 and G41 in the comparative examples AL40 and AL41, the glass composition G31 was not clearly observed, but from the surface of the Al particles 4 and the vicinity of the sintered portion thereof, the glass composition G31 A component was detected. From this, the glass composition for electrodes may react with Al particles, and it is considered that the moisture resistance of the Al-based electrode is improved for this reason.

  From the above, the glass composition for an electrode according to the present invention has an electric resistance, adhesion and moisture resistance equal to or better than those of conventional Al-based electrodes. It was found that it can also be applied.

  Next, using the glass composition for electrodes of G31, the effect of the content on the electrical resistance of the Al-based electrode was examined.

  The content of the G31 glass composition particles was in the range of 0.2 to 35 parts by weight with respect to 100 parts by weight of the Al particles. The paste for electrodes was produced so that content of the paste solid content containing Al particle | grains and glass composition particle | grain might be 70 to 75 weight%. Using the produced Al-based electrode paste, it was applied to a silicon (Si) substrate at a 20 mm square by a printing method. The coating thickness after drying at 150 ° C. was around 200 μm. After drying at 150 ° C., it was placed in an electric furnace maintained at 800 ° C. in the air, held for 5 minutes, then taken out, and the electrical resistance of the Al-based electrode after firing was measured.

  FIG. 6 shows the relationship between the G31 glass content in the Al-based electrode and the specific resistance of the Al-based electrode.

The specific resistance of the Al-based electrode tended to increase as the glass content increased, but the specific resistance increased little up to 20 parts by weight of the glass content and was good at the 10 ⁻⁵ Ωcm range. Beyond that content, the resistivity increased by an order of magnitude. Since good adhesion and moisture resistance were obtained even when the content of the glass composition was 0.2 parts by weight, the Al-based electrode can be applied in the range of 0.2 to 20 parts by weight. This range corresponded to 0.1 to 15% by volume as the glass composition in the Al-based electrode.

  In the same manner as in Examples 1 and 3, an AlCu alloy-based electrode paste was prepared using AlCu alloy particles, particles of the glass composition shown in Table 1, a resin binder, and a solvent. The AlCu alloy particles had a eutectic composition of 83 atomic% Al and 17 atomic% Cu, and had a spherical particle shape and an average particle diameter of about 2 to 3 μm.

  Further, pulverized powder having an average particle size of 3.0 μm or less was used for the glass composition particles, ethyl cellulose was used for the resin binder, and butyl carbitol acetate was used for the solvent. The content of the glass composition particles was 10 parts by weight with respect to 100 parts by weight of the AlCu alloy particles. Moreover, content of the paste solid content containing AlCu alloy particle and glass composition particle | grain was 70 to 75 weight%.

  The produced AlCu alloy-based electrode paste was applied to a silicon (Si) substrate by a printing method with a 20 mm square. The coating thickness after drying at 150 ° C. was around 40 μm. After drying at 150 ° C, put it in an electric furnace held at 600 ° C, 700 ° C and 800 ° C in the air, hold it for 5 minutes, take it out, and fire the AlCu alloy electrode after firing, electrical resistance, adhesion and moisture resistance Were evaluated in the same manner as in Examples 1 and 3.

  Table 4 summarizes the evaluation results of electrical resistance, adhesion and moisture resistance of the AlCu alloy-based electrode formed on the Si substrate.

  By changing the Al particles to AlCu alloy particles, the electrical resistance at 600 ° C. and 700 ° C. was lowered and the adhesion at 600 ° C. was improved in both the AlCu alloy-based electrodes of Examples and Comparative Examples. This is because the melting point was lowered by using the CuAl eutectic composition for the CuAl alloy particles, and the sintering of the metal particles proceeded. Almost no influence by the glass composition contained in the electrical resistance and adhesion of the AlCu alloy-based electrode was observed, but with respect to moisture resistance, as in Example 3, the influence by the glass composition was remarkably recognized. It was.

Comparative examples AC40 and AC41 AlCu alloy electrodes using conventional glass compositions G40 and G41 mainly composed of PbO or Bi ₂ O ₃ are corroded by water in a high temperature and high humidity test, and become blackened. It could not be said that it had high moisture resistance. In contrast, the AlCu alloy-based electrodes of Examples AC1 to AC37 and Comparative Examples AC38 and AC39 not containing harmful Pb and Bi produced with the Pb had equivalent or higher moisture resistance. In particular, when a glass composition containing V ₂ O ₅ was used, the moisture resistance was good as in Example 3. Furthermore, the moisture resistance at 600 ° C. was improved. This is considered to be because V in the glass composition reacts with the AlCu alloy particles and a layer that is not easily corroded by water is formed on the surface of the AlCu alloy particles.

  Using the AlCu alloy-based electrodes of representative examples AC6, AC17, AC24 and AC32 and comparative examples AC40 and AC41, changes in specific resistance depending on the firing temperature were examined in detail.

  FIG. 7 shows the examination results.

  As described above, the specific resistance of the AlCu alloy-based electrode showed almost no difference depending on the glass composition, decreased with increasing firing temperature, and exhibited good electrical resistance at 700 ° C or higher. Further, the electric resistance was lower than that of the Al-based electrode shown in FIG.

  From the above, the glass composition for electrodes of the present invention has electrical resistance, adhesion and moisture resistance that are equal to or better than those of AlCu alloy-based electrodes using conventional glass compositions for electrodes. Therefore, it was found that the present invention can also be applied to AlCu alloy-based electrodes, such as the Ag-based electrode shown in Example 1 and the Al-based electrode shown in Example 3.

  Next, using the glass composition for electrodes of G32, the effect of the content on the electrical resistance of the AlCu alloy-based electrode was examined.

  The content of G32 glass composition particles is 0.2 to 35 parts by weight with respect to 100 parts by weight of AlCu alloy particles, and the content of paste solids containing AlCu alloy particles and glass composition particles is 70 to 75. An electrode paste was prepared so as to have a weight%. The produced AlCu alloy-based electrode paste was applied to a silicon (Si) substrate by a printing method with a 20 mm square. The coating thickness after drying at 150 ° C. was around 40 μm. After drying at 150 ° C., it was placed in an electric furnace maintained at 700 ° C. in the air, held for 5 minutes, then taken out, and the electrical resistance of the fired AlCu alloy electrode was measured.

  FIG. 8 shows the relationship between the content of G32 glass in the AlCu alloy-based electrode and the specific resistance of the AlCu alloy-based electrode.

From this figure, the specific resistance of the AlCu alloy-based electrode tended to increase as the glass content increased. However, the increase in specific resistance was small up to a glass content of 20 parts by weight, which was good at 10 ^-5 Ωcm. Beyond that content, the resistivity increased by an order of magnitude. Since good adhesion and moisture resistance were obtained even when the content of the glass composition was 0.2 parts by weight, the AlCu alloy-based electrode can be applied in the range of 0.2 to 20 parts by weight. This range corresponds to 0.2 to 17% by volume as the glass composition in the AlCu alloy-based electrode.

In the same manner as in Examples 1, 3, and 4, a Cu-based electrode paste was prepared using Cu particles, glass composition particles shown in Table 1, a resin binder, and a solvent. Use spherical particles with an average particle size of 3 μm for Cu particles, pulverized powder with an average particle size of 3.0 μm or less for glass composition particles, nitrocellulose for resin binder, and butyl carbitol acetate for solvent. It was. The content of the glass composition particles was 7 parts by weight with respect to 100 parts by weight of the Cu particles. Moreover, content of paste solid content containing Cu particle | grains and glass composition particle | grains was 70 to 75 weight%. Using the produced Cu-based electrode paste, it was applied to an alumina (Al ₂ O ₃ ) substrate at a 20 mm square by a printing method. The coating thickness after drying at 110 ° C. was around 30 μm. After drying at 110 ° C, put it in an electric furnace held at 600 ° C, 700 ° C and 800 ° C in nitrogen respectively, hold it for 5 minutes, take it out, and check the electrical resistance, adhesion and moisture resistance of the Cu-based electrode after firing Evaluation was performed in the same manner as in Example 1.

  Table 5 summarizes the evaluation results of electrical resistance, adhesion and moisture resistance of the Cu-based electrode formed on the alumina substrate.

The Cu-based electrodes of Comparative Examples CU40 and CU41 using the conventional glass compositions G40 and G41 mainly composed of PbO or Bi ₂ O ₃ exhibit almost good electrical resistance and adhesion. However, due to the high transition point of G41, the electrical resistance of CU41 at 800 ° C. was good, but at 600 ° C., the firing did not proceed sufficiently and the electrical resistance was high. For this reason, the adhesion at 600 ° C. was not good. On the other hand, since the moisture resistance of G41 itself is good, the CU-based electrode CU41 using the glass composition was also good. However, G40 cannot be said to be a glass having good moisture resistance, and the moisture resistance was not sufficiently good even in the Cu-based electrode CU40 containing it.

  For Cu-based electrodes of Comparative Examples CU40 and CU41, the Cu-based electrodes of Examples CU1 to CU37 using glass compositions G1 to G37 do not contain Bi produced together with harmful Pb and Pb, and are equivalent. Excellent electrical resistance, adhesion and moisture resistance were achieved. In the Cu-based electrodes of CU34 and CU37 using G34 and G37 glasses having high transition points, it was not possible to say that the electrical resistance and adhesion at 600 ° C. were good as in Comparative Example CU41. This is because the firing of the Cu-based electrode does not proceed sufficiently at 600 ° C., and in the Cu-based electrode of the example using the glass composition having a transition point of 392 ° C. or less, good electrical resistance and adhesion Had. In addition, in the Cu-based electrodes of CU31, CU32, CU35, and CU36, the electrical resistance did not decrease even when firing at a high temperature of 800 ° C. This is presumably because the glass compositions of G31, G32, G35 and G36 react with the Cu particles upon firing at 800 ° C. Furthermore, the fact that the water resistance of Cu-based electrodes of CU1, CU2, CU4, CU5, CU9 to CU14 and CU21 was not good was largely due to the water resistance of the glass contained in the same manner as Comparative Example AG40. That is, the glass compositions of G1, G2, G4, G5, G9 to G14 and G21 were not sufficiently good in water resistance like the glass composition of G40.

The Cu-based electrodes of Examples CU1 to CU37 described above include glass compositions for electrodes G1 to G37, and the common points of these glass compositions are substantially free of harmful Pb and Bi, and at least It contains Ag, P and O. More preferably, when one or more of V, Te, Ba, W, Mo, Fe, Mn, and Zn are included, the water resistance of the Cu-based electrode is good. In the Cu-based electrode of Comparative Example CU39 containing the glass composition G39 that does not contain Ag ₂ O, the adhesion and moisture resistance were equivalent to those of Comparative Example CU40, but the electrical resistance was very large and could not be applied to the electrode. There wasn't. This is presumably because the glass composition of G39 is a V ₂ O ₅ —P ₂ O ₅ system that does not contain Ag ₂ O, so that it reacts with the Cu particles to significantly increase the resistance. Further, in the Cu-based electrode of Comparative Example CU38 using a glass composition G38 with a small amount of Ag ₂ O and a large amount of V ₂ O ₅ , G38 reacts with Cu particles, although not as much as Comparative Example CU39. The resistance was increased.

  FIG. 9 shows the relationship between the firing temperature and the specific resistance of Cu-based electrodes of representative examples CU16 and CU33 and comparative examples CU40 and CU41.

  The Cu-based electrodes of Examples CU16 and CU33 and Comparative Examples CU40 and CU41 decreased in specific resistance as the firing temperature increased, but the Cu-based electrodes of Examples CU16 and CU33 were compared to the Cu-based electrodes of Comparative Examples CU40 and CU41. Resistance was small and good.

Further, as shown in Table 5, the Cu-based electrodes of Examples CU16 and CU33 were good in both adhesion and moisture resistance, unlike the Cu-based electrodes of Comparative Examples CU40 and CU41. That is, rather than using a conventional glass composition mainly composed of PbO or Bi ₂ O ₃ for a Cu-based electrode, the glass composition for an electrode of the present invention containing no harmful Pb or Bi produced with the Pb is used. It is more advantageous to apply to Cu-based electrodes.

  Next, the effect of the content on the electrical resistance of the Cu-based electrode was examined using the glass composition for electrodes of G16.

The content of G16 glass composition particles is in the range of 3 to 35 parts by weight with respect to 100 parts by weight of Cu particles, and the content of paste solids containing Cu particles and glass composition particles is 70 to 75% by weight. An electrode paste was prepared so that Using the produced Cu-based electrode paste, it was applied to an alumina (Al ₂ O ₃ ) substrate at a 20 mm square by a printing method. The coating thickness after drying at 110 ° C. was around 30 μm. After drying at 110 ° C., it was placed in an electric furnace maintained at 800 ° C. in nitrogen, held for 5 minutes, taken out, and the electrical resistance of the Cu-based electrode after firing was measured.

  FIG. 10 shows the relationship between the G16 glass content in the Cu-based electrode and the specific resistance of the Cu-based electrode.

From this figure, the specific resistance of the Cu-based electrode tended to increase as the glass content increased, but the increase in specific resistance was small up to 15 parts by weight and was good at 10 ^-6 Ωcm. Beyond that content, the resistivity increased by an order of magnitude. Although the minimum glass content was 3 parts by weight, there was a possibility that the glass content could be further reduced because good electrical resistance and adhesion were obtained. However, if the glass composition is 3 to 15 parts by weight, there is no doubt that it is in a range that can be sufficiently applied as an electrode. Moreover, this range corresponded to 5-20 volume% as a glass composition in a Cu-type electrode.

As described above, the electrode glass composition of the present invention and the electrode paste containing the same are more harmful than the conventional electrode glass compositions mainly containing PbO and Bi ₂ O ₃ and the electrode paste containing the same. Even if Pb and Bi are not included, the same or better electrode characteristics can be expressed. That is, it can be effectively applied to various electrodes such as Ag-based, Al-based, and Cu-based electrodes while reducing the influence on the environmental load.

  In the following examples, the electrode according to the present invention was actually attached to a representative electronic component, and its applicability was confirmed.

  First, using the glass composition for an electrode of the present invention and the electrode paste using the same, a solar electronic device was manufactured and its conversion efficiency was measured.

  11-13 shows the outline of the cross section of the manufactured solar cell element, the light-receiving surface, and the back surface.

Usually, single crystal or polycrystalline Si is used for the semiconductor substrate 10 (also referred to simply as “substrate”) of the solar cell element. The semiconductor substrate 10 contains boron (B) or the like and is a p-type semiconductor. On the light receiving surface side, irregularities are formed by etching in order to suppress reflection of sunlight. The light-receiving surface is doped with phosphorus (P) or the like to form an n-type semiconductor diffusion layer 11 with a thickness of the order of submicron, and a pn junction is formed at the boundary with the p-type bulk portion. Further, an antireflection layer 12 such as Si ₃ N ₄ is formed on the light receiving surface with a film thickness of about 100 nm by vapor deposition or the like.

  Next, the formation of the light-receiving surface electrode 13 formed on the light-receiving surface, the current collecting electrode 14 and the output extraction electrode 15 formed on the back surface will be described.

  Usually, the light-receiving surface electrode 13 and the output extraction electrode 15 use an Ag-based electrode paste containing powder of the electrode glass composition, and the current collecting electrode 14 is an Al-based electrode paste containing powder of the electrode glass composition Is used. These are applied by screen printing. After drying, firing is performed at about 800 ° C. in the atmosphere, and each electrode is formed on the semiconductor substrate 10. At that time, on the light receiving surface, the glass composition contained in the light receiving surface electrode 13 reacts with the antireflection layer 12, and the light receiving surface electrode 13 and the diffusion layer 11 are electrically connected. Further, on the back surface, Al in the current collecting electrode 14 diffuses to the back surface of the semiconductor substrate 10 to form an electrode component diffusion layer 16, so that between the semiconductor substrate 10 and the current collecting electrode 14 and the semiconductor substrate 10. And an output extraction electrode 15 can be obtained ohmic contact.

In this example, a polycrystalline Si substrate (p-type semiconductor) containing B as the semiconductor substrate 10 was used. The size of the semiconductor substrate 10 was 150 mm square and the thickness was 200 μm, and the surface was etched with a strong alkaline aqueous solution to form irregularities. Subsequently, a diffusion layer 11 (n-type semiconductor layer) having a thickness of about 0.8 μm is formed by doping P on the light receiving surface, and an antireflection layer 12 is formed thereon by depositing Si ₃ N ₄ to a thickness of about 100 nm. Formed.

  For the formation of the light-receiving surface electrode 13 and the output extraction electrode 15, an Ag-based electrode paste containing a glass composition for G4, G16, G20, G40 or G41 shown in Table 1 was used. These electrode glass compositions were mixed with 7 parts by weight of 100 parts by weight of Ag particles using pulverized powder having an average particle size of 3 μm or less, as in Example 1. Also for the Ag particles, the resin binder and the solvent, the same paste as in Example 1 was used, and the paste for the Ag electrode so that the content of the paste solid content including the Ag particles and the glass composition particles was 70 to 75% by weight. Was made.

  The current collecting electrode 14 was formed by using an Al-based electrode paste containing a glass composition for G4, G16, G28, G40 or G41 shown in Table 1. These electrode glass compositions were mixed with 1 part by weight of 100 parts by weight of Al particles using pulverized powder having an average particle size of 3 μm or less in the same manner as in Example 3. The same Al particles, resin binder and solvent as in Example 3 were used, and the paste for the Al electrode so that the content of the solid content of the paste containing Al particles and glass composition particles was 70 to 75% by weight. Was made. The prepared Ag electrode paste and Al electrode paste were applied by screen printing and dried. The film thickness after drying was about 20 μm for the Ag-based electrode paste and about 40 μm for the Al-based electrode paste. Thereafter, it was rapidly heated to 800 ° C. in the atmosphere in a tunnel furnace and then rapidly cooled. As a result, the light receiving surface electrode 13 was fired on the light receiving surface, and the output extraction electrode 15 and the current collecting electrode 14 were simultaneously fired on the back surface to form the respective electrodes, thereby producing a solar cell element. In the production of the solar cell element, various combinations of Ag-based electrode paste and Al-based electrode paste prepared by changing the electrode glass composition were combined.

  The conversion efficiency of the solar cell element produced as described above was measured with a solar simulator.

  Table 6 shows the measurement results.

  At least one of the light-receiving surface electrode, the back surface output extraction electrode, and the back surface collecting electrode in the examples in Table 6 uses the glass in the examples shown in Table 1. On the other hand, the light receiving surface electrode, the back surface output extraction electrode, and the back surface collecting electrode of the comparative example in Table 6 all use the glass of the comparative example shown in Table 1.

  Comparative Example S6 is a glass composition for electrodes mainly composed of conventional PbO as an Ag-based electrode that is a light-receiving surface electrode, an Ag-based electrode that is a back surface output extraction electrode, and an Al-based electrode that is a back surface collecting electrode. Material G40 was used. The element conversion efficiency was 16.5%.

Further, in Comparative Example S7 using the conventional glass composition G41 mainly composed of Bi ₂ O ₃ for each electrode, the device conversion efficiency was 14.4%, which was very low compared to Comparative Example S6. .

The element conversion efficiency of Comparative Example S8 using G40 for the Ag-based electrode and G41 for the Al-based electrode was 16.0% between Comparative Examples S6 and S7. As described above, the element conversion efficiency varies depending on the electrode glass composition, and the glass composition containing PbO as the main component has higher element conversion efficiency than the glass composition containing Bi ₂ O ₃ as the main component.

  In contrast to these comparative examples S6 to S8, in Examples S1 to S3, the glass composition for an electrode of the present invention was used for all of the light receiving surface Ag-based electrode, the output extraction Ag-based electrode, and the current collecting Al-based electrode. The element conversion efficiencies of Examples S1 to S3 were larger than those of Comparative Examples S7 and S8, and were almost equivalent to Comparative Example S6. In other words, it has been found that harmful Pb and Bi can be removed from the solar cell element and its electrode without substantially degrading the element conversion efficiency.

  Examples S4 and S5 are cases where both the glass composition for an electrode of the present invention and the conventional glass composition for an electrode mainly composed of PbO are used, but the element conversion efficiency of Examples S4 and S5 is It was the same as Examples S1 to S3 and was almost equivalent to Comparative Example S6. That is, it was also found that harmful Pb and Bi can be reduced by using the electrode glass composition of the present invention for either an Ag-based electrode or an Al-based electrode.

  From the above, the glass composition for an electrode of the present invention and the electrode paste using the same can be applied to an electrode of a solar cell element after sufficiently considering the influence on the environmental load.

  Next, a plasma display (PDP) was manufactured using the electrode glass composition of the present invention and the electrode paste using the same.

  FIG. 14 shows an outline of a sectional view of the manufactured PDP.

  In the PDP, the front plate 20 and the back plate 21 are arranged to face each other with a gap of 100 to 150 μm, and the gap between the substrates is maintained by the partition walls 22. The peripheral portions of the front plate 20 and the back plate 21 are hermetically sealed with a sealing material 23, and the inside of the panel is filled with a rare gas. The minute spaces (cells 24) partitioned by the barrier ribs 22 are filled with red, green and blue phosphors 25, 26 and 27, respectively, and one pixel is constituted by three color cells. Each pixel emits light of each color according to the signal.

  The front plate 20 and the back plate 21 are provided with electrodes regularly arranged on a glass substrate. The display electrode 28 on the front plate 20 and the address electrode 29 on the back plate 21 are paired, and a voltage of 100 to 200 V is selectively applied between them according to the display signal, and ultraviolet rays 30 are generated by the discharge between the electrodes. Thus, the red, green and blue phosphors 25, 26 and 27 are caused to emit light to display image information. The display electrodes 28 and the address electrodes 29 are covered with dielectric layers 32 and 33 in order to protect these electrodes and control wall charges during discharge. A thick glass film is used for the dielectric layers 32 and 33.

  The back plate 21 is provided with a partition wall 22 on the surface of the dielectric layer 33 of the address electrode 29 in order to form the cell 24. The partition wall 22 is a stripe-shaped or box-shaped structure. In order to improve contrast, a black matrix 31 (black band) may be formed between the display electrodes 28 of the adjacent cells 24.

As the display electrode 28 and the address electrode 29, generally, an Ag-based electrode wiring containing an electrode glass composition mainly composed of PbO or Bi ₂ O ₃ is applied. This Ag-based electrode is formed by applying an electrode paste containing Ag fine particles, electrode glass composition fine particles, and a photosensitizer by a printing method, attaching an electrode mask after drying, and irradiating with ultraviolet rays. An electrode is formed by removing an unnecessary part and baking. The display electrodes 28, the address electrodes 29, and the black matrix 31 can be formed by a sputtering method, but a printing method is advantageous for reducing the cost. The dielectric layers 32 and 33 are generally formed by a printing method. The display electrode 28, the address electrode 29, the black matrix 31, and the dielectric layers 32 and 33 formed by a printing method are generally baked in a temperature range of 450 to 620 ° C. in an oxidizing atmosphere such as air. .

  In the front plate 20, after forming the display electrodes 28 and the black matrix 31 so as to be orthogonal to the address electrodes 29 of the back plate 21, a dielectric layer 32 is formed on the entire surface. A protective layer 34 is formed on the surface of the dielectric layer 32 in order to protect the display electrodes 28 and the like from discharge. In general, a deposited film of magnesium oxide (MgO) is used for the protective layer 34. A partition wall 22 is provided on the surface of the dielectric layer 33 of the back plate 21. The partition wall 22 made of a glass structure is made of a structural material containing at least a glass composition and a filler, and is composed of a fired body obtained by sintering the structural material. The partition wall 22 is formed by attaching a volatile sheet having a groove cut to the partition wall portion, pouring a partition wall paste into the groove, and baking at 500 to 600 ° C., thereby volatilizing the sheet and forming the partition wall 22. Can do. Alternatively, the partition wall paste 22 may be formed by applying partition wall paste on the entire surface by printing, masking after drying, removing unnecessary portions by sandblasting or chemical etching, and baking at 500 to 600 ° C. it can. The cells 24 partitioned by the barrier ribs 22 are filled with pastes of phosphors 25, 26, and 27 of each color and fired at 450 to 500 ° C., thereby red, green and blue phosphors 25, 26, 27 is formed respectively.

  Usually, the front plate 20 and the back plate 21 produced separately are opposed to each other and aligned accurately, and the peripheral edge is sealed with glass at 420 to 500 ° C. The sealing material 23 is previously formed on the peripheral edge of either the front plate 20 or the back plate 21 by a dispenser method or a printing method. In general, the sealing material 23 is formed toward the back plate 21. Further, the sealing material 23 may be temporarily fired in advance simultaneously with the firing of the red, green and blue phosphors 25, 26 and 27. By adopting this method, it is possible to remarkably reduce bubbles in the glass sealing portion, and a highly airtight, that is, highly reliable glass sealing portion is obtained.

  In the glass sealing, the gas inside the cell 24 is exhausted while being heated, and a rare gas is sealed in to complete the panel. When the sealing material 23 is temporarily fired or sealed with glass, the sealing material 23 may come into direct contact with the display electrode 28 or the address electrode 29, and the wiring material forming the electrode reacts with the sealing material 23. Thus, increasing the electrical resistance of the wiring material is a problem, and it is necessary to prevent this reaction.

  In order to light the completed panel, a voltage is applied at a portion where the display electrode 28 and the address electrode 29 intersect to discharge the rare gas in the cell 24 to obtain a plasma state. Then, using the ultraviolet light 30 generated when the rare gas in the cell 24 returns from the plasma state to the original state, the red, green and blue phosphors 25, 26, 27 are emitted to light the panel, Display image information.

  When each color is lit, address discharge is performed between the display electrode 28 and the address electrode 29 of the cell 24 to be lit, and wall charges are accumulated in the cell 24. Next, by applying a certain voltage to the display electrode pair, display discharge occurs only in the cells where the wall charges are accumulated by the address discharge, and the ultraviolet light 30 is generated to cause the phosphor to emit light. Display is performed.

  The PDP shown in FIG. 14 was manufactured by applying the Ag-based electrode paste prepared using the electrode glass composition of the present invention to the display electrode 28 of the front plate 20 and the address electrode 29 of the back plate 21.

  As the glass composition for an electrode of the present invention, fine particles obtained by grinding G16 shown in Table 1 to an average particle size of about 1 μm were used. As the Ag particles, spherical fine particles having an average particle diameter of about 1 μm were used. Compounding 5 parts by weight of the glass composition G16 for electrodes of the present invention with 100 parts by weight of the Ag fine particles, adding a photosensitizer, using ethyl cellulose as a resin binder, and using butyl carbitol acetate as a solvent, Ag A system electrode paste was prepared. This Ag electrode paste was applied to the entire surface of the front plate 20 and the back plate 21 by screen printing, and dried at 150 ° C. in the atmosphere. The film thickness after drying was about 5 μm.

  Subsequently, an electrode mask was attached to the coated surface and irradiated with ultraviolet rays to remove excess portions, and display electrodes 28 and address electrodes 29 were formed on the front plate 20 and the back plate 21. Then, it put into the electric furnace, heated to 600 degreeC with the temperature increase rate of 5 degree-C / min in air | atmosphere, hold | maintained for 10 minutes, cooled in the furnace, and each electrode was baked and produced.

  Next, the black matrix 31 and dielectric layers 32 and 33 are applied, heated to 560 ° C. at a heating rate of 5 ° C./min in the atmosphere, held for 30 minutes, and then cooled in the furnace. Was baked. In this way, the front plate 20 and the back plate 21 were separately manufactured, and the outer peripheral portion was glass-sealed to manufacture the PDP shown in FIG.

  Each of the electrodes according to the present invention could be applied to the PDP in a good appearance from the viewpoint that neither the display electrode 28 nor the address electrode 29 was discolored due to reaction or oxidation and the generation of voids.

  Next, we conducted lighting experiments on the manufactured PDP. The panel could be lit without increasing the electrical resistance of the display electrode 28 and the address electrode 29 and without decreasing the withstand voltage. In addition, there was no particular problem, and the electrode glass composition of the present invention and the electrode paste using the same were applicable as PDP electrodes. Furthermore, since harmful Pb and Bi produced with Pb are not included, the impact on the environmental load can be reduced.

  It has been found that the PDP address electrode 29 shown in FIG. 14 may have a higher electrical resistance than the display electrode 28. Using the AlCu alloy electrode examined in Example 4 as the address electrode 29, the PDP of FIG. 14 was manufactured in the same manner as in Example 7, and a lighting experiment was performed. Further, the Ag electrode according to the present invention used in Example 7 was applied to the display electrode 29.

  For forming the address electrode 29, an AlCu alloy-based electrode paste containing particles of an electrode glass composition of the present invention, AlCu alloy particles, a photosensitizer, a resin binder, and a solvent was used. As the particles of the glass composition for electrodes, fine particles obtained by pulverizing G19 shown in Table 1 to an average particle diameter of about 2 μm are used, and as the AlCu alloy particles, spherical fine particles having an average particle diameter of 1 to 2 μm are used. 10 parts by weight of fine particles of the electrode glass composition G19 of the present invention were blended with 100 parts by weight of fine particles. Further, ethyl cellulose was used as the resin binder, and butyl carbitol acetate was used as the solvent. This AlCu alloy-based electrode paste was applied to the entire surface of the back plate 21 by screen printing and dried at 150 ° C. in the atmosphere. The film thickness after drying was about 10 μm.

  Subsequently, an electrode mask was attached to the coated surface, and the excess portions were removed by irradiating with ultraviolet rays, and the address electrodes 29 were baked and formed on the back plate 21 in the same manner as in Example 7. A dielectric layer 33, barrier ribs 22, and phosphors 25, 26, and 28 were sequentially formed thereon, and a back plate 21 was produced. The back plate 21 and the front plate 20 produced in Example 7 were opposed to each other, and the outer peripheral portion was glass-sealed to produce the PDP shown in FIG. The AlCu alloy-based electrode according to the present invention applied to the address electrode 29 was in a good state in appearance with no discoloration or void formation due to reaction or oxidation.

  Next, we conducted lighting experiments on the manufactured PDP.

  The panel could be turned on without increasing the electrical resistance of the address electrode 29 and without decreasing the withstand voltage. In addition, there was no particular problem, and the electrode glass composition of the present invention and the AlCu alloy electrode paste using the same were applicable as the address electrode 29 of the PDP. Furthermore, since harmful Pb and Bi produced with Pb are not included, the impact on the environmental load can be reduced. In addition, since it can be an alternative to Ag-based electrodes, it can also contribute to cost reduction.

  Next, a multilayer circuit board (LTCC: Low Temperature Co-fired Ceramics) was manufactured using the electrode glass composition of the present invention and the electrode paste using the same.

  FIG. 15 shows an outline of a sectional view of the manufactured LTCC.

  In the LTCC shown in this figure, the wiring 40 is three-dimensionally formed between the plurality of ceramic layers 41. The wiring 40 is electrically connected by a connection wiring 42 that penetrates the ceramic layer 41.

  In the method of manufacturing this LTCC, first, a green sheet containing a mixture of ceramic powder and glass powder is produced, and a through hole is formed at a desired position. Then, an electrode paste for forming the wiring 40 is applied by a printing method and filled into the through holes. If necessary, an electrode paste for forming the wiring 40 may also be applied to the back surface of the green sheet by a printing method. At that time, the electrode paste applied to the surface is dried. The green sheets on which the electrode paste is formed are stacked and usually fired at around 900 ° C. The firing atmosphere is generally in the air when an Ag-based wiring is applied, or in nitrogen or an atmosphere containing water vapor when a Cu-based wiring is applied. By firing, the green sheet becomes the ceramic layer 41, and the electrode paste filled in the through holes becomes the connection wiring.

  In this embodiment, two types of Ag-based and Cu-based electrode pastes of the present invention were used to form the wiring 40.

  In this Ag-based electrode paste, Ag spherical fine particles having an average particle diameter of about 1 μm, fine particles of an electrode glass composition G4 having an average particle diameter of about 2 μm, ethyl cellulose as a resin binder, and butyl carbitol acetate as a solvent were used. . Further, 3 parts by weight of fine particles of the electrode glass composition G4 of the present invention were blended with 100 parts by weight of Ag fine particles.

  For the Cu-based electrode paste, Cu spherical fine particles having an average particle diameter of about 2 μm, electrode glass composition G20 fine particles having an average particle diameter of about 2 μm, nitrocellulose as a resin binder, and butyl carbitol acetate as a solvent were used. . Further, 5 parts by weight of fine particles of the electrode glass composition G20 of the present invention were blended with 100 parts by weight of the Cu fine particles.

  Wiring 40 was formed using these electrode pastes. The firing conditions were 900 ° C. in the air when applying the Ag-based electrode paste, and 950 ° C. in nitrogen containing water vapor when applying the Cu-based electrode paste. The holding time was 60 minutes. The two types of LTCC produced were both fired densely. In addition, the wiring 30 was hardly discolored due to reaction or oxidation or generation of voids, and was able to be applied to LTCC in a good appearance. As a result of evaluating the electrical characteristics of the wiring 30 in the LTCC, the LTCC to which the Cu-based electrode containing the glass composition for electrode G20 of the present invention was applied was more Ag-based electrode containing the glass composition for electrode G4 of the present invention. Although the electrical resistance of the wiring was slightly higher than that of LTCC to which No. was applied, it was more advantageous for migration between wiring than LTCC to which Ag-based electrodes were applied. Both were applicable to LTCC. In addition, since it does not contain harmful Pb or Bi, the impact on the environmental load could be reduced.

  Next, a multilayer capacitor was manufactured using the electrode glass composition of the present invention and the electrode paste using the same.

  FIG. 16 shows a cross section of the manufactured multilayer capacitor.

In the multilayer capacitor, a plurality of internal electrodes 51 are disposed in a ferroelectric glass ceramic 50 having a very large dielectric constant, and external electrodes 52 that are electrically connected to the internal electrodes 51 are formed at both ends thereof. Usually, the internal electrode 51 and the external electrode 52 are formed by applying and baking an Ag-based electrode paste containing particles of an electrode glass composition mainly composed of PbO or Bi ₂ O ₃ . The firing conditions vary depending on the ferroelectric glass ceramic 50 to be applied, but are generally heated at about 800 to 1100 ° C. in the atmosphere.

  In this example, an Ag-based electrode paste containing the electrode glass composition of the present invention was prepared and applied to the internal electrode 51 and the external electrode 52. In this Ag-based electrode paste, Ag spherical fine particles having an average particle diameter of about 1 μm, electrode glass composition G27 fine particles having an average particle diameter of about 2 μm, ethyl cellulose as a resin binder, and butyl carbitol acetate as a solvent were used. . Further, 5 parts by weight of fine particles of the electrode glass composition G27 of the present invention were blended with 100 parts by weight of Ag fine particles.

  The internal electrode 51 and the external wiring 52 were applied and formed using this Ag-based electrode paste, and fired at 950 ° C. in the atmosphere. The holding time was 30 minutes.

  The produced multilayer capacitor was fired densely. In addition, the internal electrode 51 and the external wiring 52 were hardly discolored due to reaction or oxidation and the generation of voids was not recognized, and could be applied in a good appearance.

As a result of evaluating the capacitor characteristics, the multilayer capacitor to which the Ag-based electrode containing the electrode glass composition G27 of the present invention is applied is a conventional Ag capacitor containing an electrode glass composition mainly composed of PbO or Bi ₂ O _3. Compared to the multilayer capacitor to which the system electrode is applied, the dielectric characteristics and the reliability such as moisture resistance are equal to or higher than those of the multilayer capacitor. Therefore, it was found that the present invention can be applied to the multilayer capacitor and the like. In addition, since it does not contain harmful Pb or Bi, the impact on the environmental load could be reduced.

  As mentioned above, although the application example to a typical electronic component was demonstrated in Examples 6-10, this invention is not only a solar cell element, an image display device, a multilayer circuit board, a multilayer capacitor, but the electrode containing a glass composition It can be used for electronic parts in general. Moreover, since the glass composition for electrodes of the present invention has a low transition point and low meltability, it may be applicable to other than electrodes. For example, adhesion at low temperature, sealing, coating and the like can be mentioned.

  Next, the solar cell element of the present invention described in Example 6 was tested by changing the Al electrode on the back collecting electrode.

  Table 7 shows the conductive glass composition studied for the back collector electrode, its softening point and ion fraction.

The raw materials for glass include V ₂ O ₅ , P ₂ O ₅ , Sb ₂ O ₃ , MnO ₂ , Fe ₂ O ₃ , Bi ₂ O ₃ , Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , BaCO ₃ , ZnO, WO ₃ , TeO ₂ , CuO, MoO ₃ and B ₂ O ₃ , prepare about 200 g of glass composition ratio in Table 7, put the mixture in a crucible, 1 at 900 ° C ~ 1500 ° C Melted for hours. Then, the glass powder was produced similarly to Example 1, and the softening point of glass was measured by DTA.

  FIG. 17 shows a typical DTA curve of glass.

  The softening point of glass generally refers to the second endothermic peak of the glass composition shown in FIG.

  Subsequently, in order to investigate the ion fraction of the transition metal in the conductive glass, the transition metal in the manufactured conductive glass conforms to JIS-G1221, JIS-G1220, JIS-G1218, JIS-H1353 and JIS-G1213. Then, it was measured by a redox titration method.

  Next, an Al-based electrode paste was prepared using Al particles, particles of the conductive glass composition prepared in Table 7, a resin binder, and a solvent. The Al particles are spherical particles having an average particle diameter of 4 μm used in Example 3, the conductive glass composition particles are pulverized powder having an average particle diameter of 3.0 μm or less, the resin binder is ethyl cellulose, and the solvent is butyl carbitol acetate. Was used. The content of the conductive glass composition particles was 0.5 parts by weight with respect to 100 parts by weight of the Al particles. Moreover, content of paste solid content containing Al particle and electroconductive glass composition particle | grain was 70 to 75 weight%. A solar cell element was produced in the same manner as in Example 6 using the produced Al-based electrode paste.

  The light-receiving surface electrode 13 and the output extraction electrode 15 shown in FIGS. 11 to 13 were formed using an Ag-based electrode paste AG4 containing the G4 electrode glass composition shown in Table 1. In addition, the collector electrode 14 is formed by using the electrode-based glass compositions G4, G16, G40 and G41 shown in Table 1 or the Al-based electrode pastes AN42 to AN79 containing the conductive glass compositions N42 to N79. The Al-based electrode pastes AN4, AN16, AN40 and AN41 were used.

  The prepared Ag-based electrode paste and Al-based electrode paste were each applied by screen printing and dried. The film thickness after drying was about 20 μm for the Ag-based electrode paste and about 40 μm for the Al-based electrode paste. After that, it was rapidly heated to 800 ° C in the atmosphere in a tunnel furnace and then rapidly cooled. As a result, the light receiving surface electrode 13 was fired on the light receiving surface, and the output extraction electrode 15 and the current collecting electrode 14 were simultaneously fired on the back surface to form the respective electrodes, thereby producing a solar cell element.

  The electrical resistance, adhesion and moisture resistance of the Al-based electrode of the solar cell element produced as described above were evaluated. For electrical resistance, the specific resistance at room temperature was measured by the four probe method. At this time, relative evaluation was performed assuming that the specific resistance of AN40 was 100. The adhesion and moisture resistance were evaluated in the same manner as in Example 1.

  Table 8 summarizes these evaluation results.

  Here, when the relationship between the electric resistance of the current collecting electrode and the ion fraction was examined, the conductive glass composition that was equal to or less than the reference AN40 had an ion fraction greater than 0.5, that is, It was found that the above formula (1) was satisfied.

  More preferably, the ion fraction is> 0.6, and still more preferably, the ion fraction is> 0.7.

  In addition, when the relationship between the electrical resistance of the current collecting electrode and the ion fraction was examined, the conductive glass composition that was equal to or less than that of the reference AN40 had a component content in an oxide equivalent mass ratio. It was found that the relationship of the above formula (2) was satisfied.

Next, when the relationship between the adhesion and the softening point was examined, it was found that the softening point was 450 ° C. or less. In addition, the relationship between moisture resistance and the conductive glass composition and softening point revealed that the moisture resistance is good in the case of a conductive glass composition having a softening point of 500 ° C. or lower and containing V ₂ O _5. did.

  Next, the N58 conductive glass composition was used to examine its content. As in Example 11, 4 μm Al spherical particles were used for the metal particles, pulverized powder having an average particle size of 3.0 μm or less for the conductive glass composition particles, ethyl cellulose for the resin binder, and butyl carbitol acetate for the solvent. Thus, an Al-based electrode paste was prepared. The content of the conductive glass composition particles is in the range of 0.05 to 20 parts by weight with respect to 100 parts by weight of the Al particles, and the content of the paste solid content including the Al particles and the conductive glass composition particles is 70 to 75. % By weight. A solar cell element was produced using the produced Al-based electrode paste in the same manner as in Example 11, and the electrical resistance of the fired Al-based electrode was measured.

  FIG. 18 shows the relationship between the N58 conductive glass content in the Al-based electrode and the specific resistance of the Al-based electrode.

The specific resistance of Al-based electrodes tended to increase with increasing conductive glass content. When the conductive glass content is 6 parts by weight or less, the specific resistance is 10 ⁻⁴ Ωcm or less, which is desirable as an electrode. However, when the conductive glass content is less than 0.1 parts by weight, a problem has occurred that the electrode is peeled off. Therefore, if the conductive glass content is 0.1 to 6 parts by weight, the electrode is within a preferred range. There is no doubt that there is. Moreover, this range corresponded to 0.1-5 volume% as a glass composition in an Al-type electrode.

  In this example, solar cell elements were produced when the electrode paste of the present invention was variously combined with the light-receiving surface electrode 13, the back surface output extraction electrode 15, and the collector electrode 14. The method for producing the solar cell element was produced in the same manner as in Example 6. Here, for the formation of the light-receiving surface electrode 13 and the output extraction electrode 15, the same Ag-based electrode paste as in Example 6 containing the glass compositions for electrodes G4 and G40 shown in Table 1 was used. In addition, the collector electrode 14 is formed for the same Al-based electrode as in Example 11 including the N42 and N58 conductive glass compositions shown in Table 7 and the G40 and G41 electrode glass compositions shown in Table 1. A paste was used.

  The conversion efficiency of the manufactured solar cell element was evaluated by a solar simulator. At this time, the appearance of the solar cell element was also evaluated.

  Table 9 shows the results.

  In the table, G40 and G41 use the comparative glass shown in Table 1.

  With respect to the appearance of the solar cell element, the case where discoloration was observed at the interface between the output extraction electrode 15 and the current collecting electrode 14 after firing was indicated as x, and the case where discoloration was not observed was indicated as ◯.

  When the appearance of the above results was analyzed as x, it was found that the components resulting from the discoloration were Pb, Bi and V compounds. Therefore, the back surface output extraction electrode 15 and the current collecting electrode 14 have compatibility, and the glass that was good in Example 1 was used for the back surface output extraction electrode 15, and the current collection electrode was good in Example 11. It has been found that when glass is used, the formation of compounds by glass components can be suppressed, and the conversion efficiency is good.

  1: Ag sintered particles, 2: Glass composition for electrodes, 3: Ag fine particles, 4: Al particles, 5: Si substrate, 6: Alloy layer, 10: Semiconductor substrate, 11: Diffusion layer, 12: Antireflection layer , 13: light receiving surface electrode, 14: current collecting electrode, 15: output extraction electrode, 16: electrode component diffusion layer, 20: front plate, 21: back plate, 22: partition wall, 23: sealing material, 24: cell, 25, 26, 27: phosphor, 28: display electrode, 29: address electrode, 30: UV, 31: black matrix, 32, 33: dielectric layer, 34: protective layer, 40: wiring, 41: ceramics layer, 42: Connection wiring, 50: Ferroelectric glass ceramics, 51: Internal electrode, 52: External electrode.

Claims (26)

  A glass composition for an electrode, comprising silver, phosphorus and oxygen, and substantially free of lead.   Furthermore, vanadium is contained, The glass composition for electrodes of Claim 1 characterized by the above-mentioned.   Furthermore, tellurium is contained, The glass composition for electrodes of Claim 1 characterized by the above-mentioned.   The electrode glass composition according to claim 1, further comprising at least one of barium, tungsten, molybdenum, iron, manganese, and zinc. In terms of oxide, 5 to 60% by weight of Ag ₂ O, ₅ to 50% by weight of P ₂ O _{5, 0} to 50% by weight of V ₂ O ₅ , 0 to 30% by weight of TeO ₂ , other oxides Is 0 to 40 wt%, and further, the total of Ag ₂ O and V ₂ O ₅ is 30 to 86 wt%, and the total of P ₂ O ₅ and TeO ₂ is 14 to 50 wt% The glass composition for an electrode according to claim 1. 6. The glass composition for an electrode according to claim 5, wherein the other oxide is at least one selected from the group consisting of BaO, WO ₃ , MoO ₃ , Fe ₂ O ₃ , MnO ₂ and ZnO. . In terms of oxide, the total of Ag ₂ O and V ₂ O ₅ is 40 to 70% by weight, Ag ₂ O is 10 to 50% by weight, and V ₂ O ₅ is 20 to 50% by weight. The sum of P ₂ O ₅ and TeO ₂ is 25-50 wt%, P ₂ O ₅ is 10-30 wt%, and TeO ₂ is 0-30 wt%, BaO , WO ₃ , Fe ₂ O ₃ and ZnO are 0-30 wt%, BaO is 0-20 wt%, WO ₃ is 0-10 wt%, and Fe ₂ The glass composition for an electrode according to claim 1, wherein O ₃ is 0 to 10% by weight and ZnO is 0 to 15% by weight.   The glass composition for an electrode according to claim 1, wherein the transition point is 392 ° C or lower.   The glass composition for an electrode according to claim 8, wherein the transition point is 310 ° C. or lower.   An electrode paste comprising: metal particles containing one or more metal elements of silver, aluminum, and copper; particles of the glass composition for an electrode according to claim 1; a resin binder; and a solvent. .   The electrode paste according to claim 10, comprising 100 parts by weight of the metal particles and 0.2 to 20 parts by weight of the glass composition for an electrode.   The electrode paste according to claim 10, wherein the metal particles contain silver as a main component, and include 100 parts by weight of the metal particles and 3 to 15 parts by weight of the glass composition for an electrode.   The electrode paste according to claim 10, wherein the metal particles contain aluminum as a main component, and include 100 parts by weight of the metal particles and 0.2 to 20 parts by weight of the glass composition for an electrode.   The electrode paste according to claim 10, wherein the metal particles contain copper as a main component, and include 100 parts by weight of the metal particles and 3 to 15 parts by weight of the glass composition for an electrode.   The electrode paste according to claim 10, wherein the resin binder is ethyl cellulose or nitrocellulose, and the solvent is butyl carbitol acetate or α-terpineol.   An electronic component comprising an electrode formed using the electrode paste according to claim 10.   The electronic component according to claim 16, wherein the electrode glass composition contained in the electrode is 0.1 to 30% by volume.   18. The electronic component according to claim 17, wherein the electrode contains silver as a main component of a metal conductor, and the electrode glass composition contained in the electrode is 5 to 30% by volume.   The electronic component according to claim 17, wherein the electrode contains aluminum as a main component of a metal conductor, and the glass composition for an electrode contained in the electrode is 0.1 to 15% by volume.   18. The electronic component according to claim 17, wherein the electrode contains copper as a main component of a metal conductor, and the glass composition for an electrode contained in the electrode is 5 to 20% by volume.   The electronic component according to claim 16, wherein the electronic component is a solar cell element, an image display device, a multilayer capacitor, or a multilayer circuit board.   The electronic component according to claim 16, wherein the electronic component is a solar cell element using a silicon substrate. A solar cell element comprising a substrate, a collector electrode formed using the electrode paste according to claim 10 on the surface of the substrate, and an output extraction electrode, wherein the collector electrode comprises a transition metal and a phosphorus The transition metal is present in a plurality of oxidation number states, and the presence ratio of the element exhibiting the highest oxidation number state in the transition metal is represented by the following formula (1): A solar cell element characterized by satisfying the relationship.

(In the formula, {} means the concentration of ions or atoms in parentheses (unit: mol / L).) The current collecting electrode has aluminum as a main component of the conductor, and the conductive glass composition does not include a RoHS directive prohibited substance, but includes V and P as main components, and an oxide of the component 24. The solar cell element according to claim 23, wherein the mass ratio in conversion satisfies the relationship of the following formula (2).

(In the formula, [] means a mass ratio (unit: mass%) converted to an oxide in parentheses.)   24. The solar cell element according to claim 23, wherein the conductive glass composition contained in the current collecting electrode is 0.1 to 5% by volume.   24. The solar cell element according to claim 23, wherein the output extraction electrode is formed using the electrode paste according to claim 10.

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