KR20220023587A - Conductuive connect composition and electronic memner - Google Patents

Abstract

A conductive bonding composition according to an embodiment includes metal particle and an organic vehicle. The metal particle includes first particle and second particle. A melting point of the first particle is greater than a melting point of the second particle, and at least one of the first particle and the second particle includes particles having different particle diameters. The weight% ratio of the first particle to the second particle is 4:6 to 7:3.

Description

Conductive bonding composition and electronic component

Examples are directed to conductive bonding compositions.

Transient liquid phase sintering (TLPS) is a bonding material for electronic components, and may be used for bonding components and components or for physical or electrical bonding between components and circuit boards.

This transition liquid sintering composition is a composite composition of a low-melting-point material and a high-melting-point material, and is alloyed at a bonding temperature of 300 ° C. or less to form a joint, and the alloy produced after joining does not re-melt even at a temperature higher than 400 ° C. High temperature stability can be obtained.

On the other hand, the transition liquid phase sintering composition rapidly reacts with the surface of the high-melting-point metal when melting the low-melting-point metal to generate an alloy phase, but when the low-melting-point metal layer is included in excess, the remaining low-melting-point metal diffuses into the high-melting-point metal and reacts Therefore, there is a problem that the alloy takes a long time. In addition, when the unreacted low-melting-point metal remains, there is a problem in that the electrical or mechanical properties of the joint portion are weakened.

The transition liquid phase sintering composition is known as a layer-by-layer type in which a low-melting-point metal layer and a high-melting-point metal layer are alternately arranged, or a particulate composition in which low-melting-point metal particles and high-melting-point metal particles are mixed.

In the case of the transition liquid phase sintering composition in the form of particles, the reaction surface area is much larger than that of the layer by layer type, so a fast alloying reaction can be induced as a whole. A structure in which voids are formed may be formed, so that the density of the junction portion may be lowered. This lowered density has problems in that the bonding strength is lowered and electrical conductivity and thermal conductivity are lowered.

Therefore, there is a need for a conductive bonding composition having a new structure that can solve the above problems.

An embodiment is to provide a conductive bonding composition capable of reducing pores of a bonding member and having improved electrical conductivity, bonding strength and thermal conductivity.

A conductive bonding composition according to an embodiment includes a metal particle and an organic vehicle, the metal particle includes a first particle and a second particle, a melting point of the first particle is greater than a melting point of the second particle, and the At least one of the first particle and the second particle includes particles having different particle diameters, and a weight % ratio of the first particle and the second particle is 4:6 to 7:3.

The conductive bonding composition according to the embodiment may include a first particle having a high melting point and a second particle having a low melting point.

The conductive bonding composition according to the embodiment may increase the density of the conductive bonding composition by controlling the particle size sizes of the first particles and the second particles, and thus the electrical conductivity of the bonding member manufactured by the conductive bonding composition and strength can be improved.

In addition, the conductive bonding composition according to the embodiment may reduce the porosity of the bonding member manufactured by the conductive bonding composition by controlling the particle size of the first particle and the second particle.

Accordingly, it is possible to prevent a decrease in strength of the bonding member due to the pores of the bonding member.

In addition, the conductive bonding composition according to the embodiment controls the content range of the first particle and the second particle so that the second particle having a low melting point exists as a single phase in the bonding member manufactured by the conductive bonding composition. can be prevented

Accordingly, in the bonding member according to the embodiment, it is possible to prevent the electrical conductivity and mechanical properties of the bonding member from being deteriorated due to residual second particles having a low melting point.

1 is a view showing an example of a circuit board to which a conductive bonding composition according to an embodiment is applied.
2 and 3 are views showing the structure of the conductive bonding composition before firing according to the embodiment.
4 is a view showing the structure after firing of the conductive bonding composition according to the embodiment.
5 to 7 are views illustrating scanning electron microscope (SEM) pictures for explaining pores of a bonding member formed by a conductive bonding composition according to Examples and Comparative Examples.
8 to 11 are views showing scanning electron microscope (SEM) pictures for explaining the particle shape of the bonding member formed by the conductive bonding composition according to Examples and Comparative Examples.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical spirit of the present invention is not limited to some of the described embodiments, but may be implemented in various different forms, and within the scope of the technical spirit of the present invention, one or more of the components may be selected between the embodiments. It can be used by combining or substituted with . In addition, terms (including technical and scientific terms) used in the embodiments of the present invention may be generally understood by those of ordinary skill in the art to which the present invention belongs, unless specifically defined and described explicitly. It may be interpreted as a meaning, and generally used terms such as terms defined in advance may be interpreted in consideration of the contextual meaning of the related art.

In addition, the terminology used in the embodiments of the present invention is for describing the embodiments and is not intended to limit the present invention. In this specification, the singular form may also include the plural form unless otherwise specified in the phrase, and when it is described as "at least one (or one or more) of A and (and) B, C", it can be combined with A, B, and C. It may include one or more of all possible combinations.

In addition, in describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the component from other components, and are not limited to the essence, order, or order of the component by the term.

And, when it is described that a component is 'connected', 'coupled' or 'connected' to another component, the component is not only directly connected, coupled or connected to the other component, but also with the component It may also include a case of 'connected', 'coupled' or 'connected' due to another element between the other elements.

In addition, when it is described as being formed or disposed on "above (above) or below (below)" of each component, the top (above) or bottom (below) is one as well as when two components are in direct contact with each other. Also includes a case in which another component as described above is formed or disposed between two components.

In addition, when expressed as “up (up) or down (down)”, it may include not only the upward direction but also the meaning of the downward direction based on one component.

Hereinafter, a conductive bonding composition according to an embodiment will be described with reference to the drawings.

First, an example to which the conductive bonding composition according to the embodiment is applied will be described with reference to FIG. 1 . The conductive bonding composition described below is defined as a transition liquid phase sintering composition including particles having different melting points.

1 is a view showing a cross-sectional view of a circuit board to which the conductive bonding composition is applied.

Referring to FIG. 1 , the circuit board 1000 may include a substrate 100 , a circuit pattern layer 200 disposed on the substrate 100 , a protection layer 300 , and a chip 400 .

The substrate 100 may support the circuit pattern layer 200 , the protective layer 300 , and the heat dissipation unit 400 .

The substrate 100 may include a first surface 1S and a second surface 2S opposite to the first surface 1S. The first surface 1S of the substrate 100 may support the circuit pattern layer 200 and the protective layer 300 .

The substrate 100 may include a chip mounting area 1A. In detail, the protective layer 300 is not disposed on the first surface 1S of the substrate 100 , and a chip mounting region 1A exposing the substrate 100 and the circuit pattern layer 200 is included. can do.

The substrate 100 may be a flexible substrate. Accordingly, the substrate 100 may be partially bent. That is, the substrate 100 may include a flexible plastic. For example, the substrate 100 may be a polyimide (PI) substrate. However, the embodiment is not limited thereto, and the substrate 100 may be a substrate made of a polymer material such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN).

A circuit pattern layer 200 may be disposed on the substrate 100 . In detail, the circuit pattern layer 200 may be disposed on the first surface 1S of the substrate 100 . The circuit pattern layer 200 may be a plurality of patterned wirings. For example, the plurality of circuit pattern layers 200 may be disposed to be spaced apart from each other on the substrate 100 .

The circuit pattern layer 200 may be connected to the chip 400 disposed in the chip mounting area 1A and an external device. Accordingly, communication between the chip 400 and an external device and power supply to the chip 400 may be performed.

The circuit pattern layer 200 may include a metal material having excellent electrical conductivity. In more detail, the circuit pattern layer 200 may include copper (Cu). However, the embodiment is not limited thereto, and the circuit pattern layer 200 may include copper (Cu), aluminum (Al), chromium (Cr), nickel (Ni), silver (Ag), or molybdenum (Mo). Of course, it may include at least one metal among gold (Au), titanium (Ti), and alloys thereof.

A protective layer 300 may be disposed on the circuit pattern layer 200 .

The protective layer 300 may be partially disposed on the circuit pattern layer 200 . The protective layer 300 is disposed while covering the circuit pattern layer 200 , and the circuit pattern layer 200 may prevent damage or film removal due to oxidation by the protective layer 300 .

The protective layer 300 may be partially disposed in an area except for an area for the circuit pattern layer 200 to be electrically connected to the chip 400 and external devices such as a display panel and a main board.

The protective layer 300 may include solder paste. For example, the protective layer 300 may include a solder paste including a thermosetting resin, a thermoplastic resin, a filler, a curing agent, or a curing accelerator.

The chip 400 may be disposed in the chip mounting area 1A of the substrate 100 .

The chip 400 may include a semiconductor chip. For example, the chip 400 may include an integrated circuit (IC) chip or a large scale integrated circuit (LSI) chip.

The chip 400 may be disposed on the circuit pattern layer 200 on which the protective layer 300 is not disposed.

In detail, the terminal of the chip 400 may be electrically connected to the circuit pattern layer 200 by direct or indirect contact.

For example, as shown in FIG. 1 , a bonding member 500 is disposed between the chip 600 and the circuit pattern layer 200 , and the chip 400 and the circuit pattern layer 200 are interposed between the chip 400 and the circuit pattern layer 200 . It may be electrically connected through the bonding member 500 .

The conductive bonding composition according to the embodiment may be applied to the bonding member 500 . That is, the conductive bonding composition may be applied to a bonding member electrically bonding the chip and the circuit pattern layer.

On the other hand, in the case of a conductive bonding composition including high-melting-point particles and low-melting-point particles, pores according to the low-melting-point particles may occur after firing. That is, a plurality of pores may be formed in the bonding member, thereby reducing the density of the bonding member. Accordingly, as the bonding strength between the chip and the circuit pattern is lowered, there is a problem in that the reliability of the electronic component is lowered.

Accordingly, the conductive bonding composition described below is a composition capable of improving the reliability of an electronic component including a bonding member formed by the conductive bonding composition by solving the above problems.

2 to 4 are views for explaining the conductive bonding composition according to the embodiment.

2 and 3 , the conductive bonding composition may include a first particle 11 and a second particle 12 .

The first particle 11 and the second particle 12 may have melting points of different temperatures. In detail, the melting point of the first particle 11 may be greater than the melting point of the second particle 12 . That is, the first particle 11 may be a high melting point particle, and the second particle 12 may be a low melting point particle.

The first particle 11 and the second particle 12 may include a metal.

In detail, the first particle 11 may include a metal having a high melting point characteristic. For example, the first particle 11 may include at least one of copper (Cu), silver (Ag), nickel (Ni), gold (Au), and aluminum (Al).

In addition, the second particle 12 may include a metal having a low melting point characteristic. For example, the second particle 12 may include at least one of tin (Sn), zinc (Zn), indium (In), and gallium (Ga).

The first particle 11 and the second particle 12 may be included in the same or different content.

In detail, the first particle 11 may be included in an amount of 20 wt% to 70 wt% based on the entire conductive bonding composition. In more detail, the first particle 11 may be included in an amount of 30% to 60% by weight based on the entire conductive bonding composition. In more detail, the first particle 11 may be included in an amount of 40 wt% to 50 wt% based on the entire conductive bonding composition.

In addition, the second particle 12 may be included in an amount of 20% to 60% by weight based on the entire conductive bonding composition. In more detail, the second particle 12 may be included in an amount of 25 wt% to 55 wt% based on the entire conductive bonding composition. In more detail, the second particle 12 may be included in an amount of 30% to 50% by weight based on the entire conductive bonding composition.

In addition, the first particle 11 and the second particle 12 may be included in a constant ratio within the weight % range. In detail, the weight% ratio of the first particle 11 and the second particle 12 may be 4:6 to 7:3.

When the weight % ratio of the first particles 11 to the second particles 12 is out of the above range, the second particles 12 remaining after sintering the conductive bonding composition and the electrical conductivity of the bonding member due to the increase in porosity Properties and strength may be reduced.

The first particle 11 and the second particle 12 may have a size within a certain range.

In detail, the particle diameter of the first particles 11 may be 30 μm or less. More specifically, the particle diameter of the first particles 11 may be 0.1 μm to 30 μm. In more detail, the particle diameter of the first particles 11 may be in the range of 1 μm to 20 μm. More specifically, the particle diameter of the first particles 11 may be in the range of 2 μm to 10 μm.

In addition, the first particle 11 may include two or more particles having different sizes. For example, the first particle 11 may include two particles having different sizes. For example, the first particles 11 may include 1-1 particles 11-1 and 1-2 particles 11-2 having different particle sizes.

The 1-1 particle 11-1 and the 1-2 particle 11-2 may have different particle sizes. A particle diameter of the 1-1 particle 11-1 may be larger than a particle diameter of the first 1-2 particle 11-2. In detail, the ratio of the particle diameter of the 1-1 particle 11-1 to the particle diameter of the 1-2 particle 11-2 may be 2:1 to 10:1. In more detail, a ratio of the particle diameter of the 1-1 particle 11-1 to the particle diameter of the first 1-2 particle 11-2 may be 3:1 to 5:1.

As the first particles 11 include a plurality of particles having different sizes, pores of the conductive bonding composition may be reduced. That is, the first 1-2 particles having a small particle size may be disposed between the 1-1 particles 11-1 having a large particle size, thereby reducing the pore size of the conductive bonding composition before sintering.

Accordingly, when the conductive bonding composition is sintered, more first particles 11 can be sintered in a short time, thereby improving adhesion and electrical properties of the bonding member formed by the conductive bonding composition.

A particle diameter of the second particle 12 may be different from that of the first particle 11 . In detail, the particle diameter of the second particle 12 may be smaller than that of the first particle 11 . In more detail, the second particle 12 may include at least one particle having a smaller particle diameter than the first particle 11 .

The particle diameter of the second particle 12 may be 30 μm or less, more specifically, the particle diameter of the second particle 12 may be 0.1 μm to 30 μm. In more detail, the particle diameter of the second particles 12 may be in the range of 1 μm to 20 μm. More specifically, the particle diameter of the second particles 12 may be in the range of 2 μm to 10 μm.

The particle diameter of the second particle 12 may be smaller than that of the first particle 11 within the particle diameter size range. In detail, the particle diameter of the second particle 12 may be 50% or less of the particle diameter of the first particle 11 within the particle diameter size range. In more detail, the particle diameter of the second particle 12 may be 10% to 50% of the particle diameter of the first particle 11 within the particle diameter size range. In more detail, the particle diameter of the second particle 12 may be 20% to 40% of the particle diameter of the first particle 11 within the particle diameter size range.

When the particle diameter of the second particle 12 exceeds 50% of the particle diameter of the first particle 11, the porosity of the bonding member formed by sintering the conductive bonding composition may increase.

That is, since the second particle 12 has a lower melting point than the first particle 11 , it may react faster than the first particle 11 and melt when the conductive bonding composition is sintered. Accordingly, pores may be formed in the bonding member at the position where the second particles 12 were located.

However, the conductive bonding composition according to the embodiment may reduce the particle size of the second particles 12, thereby reducing the pore size formed by the second particles 12 when the conductive bonding composition is sintered. . Accordingly, the porosity of the bonding member formed by the conductive bonding composition may be reduced.

In addition, the second particle 12 may include two or more particles having different sizes. For example, the second particle 12 may include two particles having different sizes. For example, the second particles 12 may include 2-1 particles 12-1 and 2-2 particles having different particle diameters.

The 2-1 th particle 12-1 and the 2-2 th particle 12-2 may have different particle sizes. A particle diameter of the second-first particle 12-1 may be larger than a particle diameter of the second-second particle 12-2.

A particle diameter of the second-second particle 12-2 may be similar to the size of the second particle 12 described above. That is, the particle diameter of the 2-2 particle 12-2 may be 50% or less of the particle diameter of the first particle 11 .

Also, the particle diameter of the second-first particle 12-1 may be larger than that of the second-second particle 12-2. In detail, the particle diameter of the 2-1 particle 12-1 may exceed 50% of the particle diameter of the first particle 11 . In more detail, the particle diameter of the 2-1 particle 12-1 may be greater than 50% to 100% of the particle diameter of the first particle 11 .

When the particle diameter of the 2-2 particle 12-2 is larger than that of the first particle 11, when the conductive bonding composition is sintered, the 2-2 particle 12-2 reacts rapidly. Accordingly, the porosity of the bonding member may be increased.

Also, the ratio of the particle diameter of the 2-1 particle 12-1 to the particle diameter of the 2-2 particle 12-2 may be 2:1 to 10:1. In more detail, a ratio of the particle diameter of the 2-1 particle 12-1 to the particle diameter of the 2-2 particle 12-2 may be 3:1 to 5:1.

As the second particles 12 include a plurality of particles having different sizes, pores of the conductive bonding composition may be reduced. That is, the 2-2 particles having a small particle size may be disposed between the 2-1 particles having a large particle size, thereby reducing the pore size of the conductive bonding composition before sintering.

Accordingly, when the conductive bonding composition is sintered, more second particles 12 can be sintered, thereby improving adhesion and electrical properties of a bonding member formed by the conductive bonding composition.

The first particles 11 and the second particles 12 of the conductive bonding composition may be formed in a combination of various sizes.

In detail, referring to FIG. 2 , the conductive bonding composition has a single or similar size to the first particles including 1-1 particles 11-1 and 1-2 particles 11-2 having different sizes. It may include a second particle 12 having a.

In this case, the size of the second particle 12 may be smaller than the size of the 1-1 particle 11-1. That is, the size of the second particle 12 may be the same as, larger than, or smaller than the size of the first 1-2 particles 11-2, and may be smaller than the size of the 1-1 particle 11-1. Accordingly, the pore size of the bonding member formed by firing the conductive bonding composition may be reduced.

Since the first particles include particles having different sizes, pores of the conductive bonding composition may be reduced. Accordingly, bonding characteristics and electrical characteristics of a bonding member formed by firing the conductive bonding composition may be improved.

In addition, referring to FIG. 3 , the conductive bonding composition has a size different from that of the first particles including 1-1 particles 11-1 and 1-2 particles 11-2 having different sizes. The branch may include a second particle including the 2-1 particle 12-1 and the 2-2 particle 12-2.

In this case, the size of the second-first particle 12-1 may be larger than the size of the second-second particle 12-2.

In detail, the size of the 2-1 th particle 12-1 may be the same as or smaller than the size of the 1-1 th particle 11-1.

In addition, the size of the 2-2nd particle 12-2 may be smaller than the size of the 1-1 particle 11-1. That is, the size of the second-second particles 12-2 may be the same as, smaller than, or larger than the size of the second-second (11-2) particles.

Accordingly, the pore size of the bonding member formed by firing the conductive bonding composition may be reduced.

In addition, since the first and second particles include particles having different sizes, pores of the conductive bonding composition may be reduced. Accordingly, bonding characteristics and electrical characteristics of a bonding member formed by firing the conductive bonding composition may be improved.

The conductive bonding composition may include an organic vehicle for uniform mixing and pasting of the first particles 11 and the second particles 12 . The organic vehicle may be one in which a binder is dissolved in a solvent. An organic solvent such as terpineol or carbidol may be used as the solvent, and an acrylic resin, a cellulose resin, an alkyd resin, or the like may be used as the binder.

In addition, the organic vehicle may include a flux component. For example, the organic vehicle may contain a flux component such as rosin or a rosin modified product (derivative).

Accordingly, surface oxidation of the first and second particles of the conductive bonding composition can be prevented, and surface oxide films of the first and second particles can be reduced and removed.

Accordingly, when the conductive bonding composition is sintered, the alloy reaction of the first particles and the second particles may be facilitated, and the process may be easily performed in a vacuum or inert gas atmosphere and air.

4 is a view showing a bonding member formed by firing the conductive bonding composition of FIGS. 2 and 3 .

Referring to FIG. 4 , the conductive bonding composition may be sintered by heat treatment. In detail, the conductive bonding composition may be heat-treated at a temperature equal to or higher than the melting point of the second particles, whereby the first particles and the second particles may react with each other to be alloyed to form a bonding member.

On the other hand, as described above, since the conductive bonding composition includes an organic vehicle including a flux component, a process of pretreating the surface of the substrate on which the conductive bonding composition is deposited prior to heat treatment of the conductive bonding composition is not required. does not In addition, the process can be carried out in air.

Accordingly, since a separate pretreatment process is not required and the process can be performed even under conditions other than an inert atmosphere, process efficiency can be facilitated.

4, the conductive bonding composition according to the embodiment controls the particle size of the first particles and the second particles, so that the second particles having a small melting point react only with the surface of the first particles having a large melting point to form an alloy. By inducing the alloy 20 may be formed.

That is, alloying may proceed in a core-shell structure in which the first particle is a core and the second particle is a shell. Accordingly, since the core has a form in which the first particles having a high melting point remain, it is possible to reduce the reaction time.

That is, referring to FIG. 4 , the single phase shape of the second particle having a low melting point is minimized inside the bonding member, that is, the alloy 20, and only the single phase shape of the first particle 11 having a high melting point remains, It is possible to minimize the decrease in mechanical and electrical properties of the bonding member due to the presence of a single phase of the melting point particles.

In addition, by controlling the particle size of the second particle having a small melting point, it is possible to reduce the pore size and porosity of the bonding member according to the second particle, thereby reducing the overall porosity of the bonding member formed by the conductive bonding composition. .

Hereinafter, the present invention will be described in more detail through conductive bonding compositions according to Examples and Comparative Examples. These manufacturing examples are merely presented as examples in order to explain the present invention in more detail. Therefore, the present invention is not limited to these preparation examples.

Preparation Example 1

Conductive pastes according to Examples and Comparative Examples having different weight % ratios and particle size sizes were printed on an alumina circuit board having 0.3 mm copper foil bonded to the upper and lower portions, respectively, and then dried.

Then, a gold-plated copper block with a size of 3 mm * 3 mm * 1 mm was placed on the dried conductive paste, and a pressure of 15 MPa was applied to perform a bonding process at 300° C./30 min in a nitrogen (N 2 ) atmosphere.

Next, the bonding strength of the bonded Cu block was measured using a die shear strength measuring device, and cross-sectional analysis was performed using SEM.

Cu:Sn
(wt% ratio) Cu particle size
(μm) Sn particle size
(μm) process temperature
(℃) process pressure
(MPa) process conditions Example 1 5:5 10, 2.5 3 300 15 N ₂ Example 2 7:3 10, 2.5 3 300 15 N ₂ Example 3 6:4 10, 2.5 3 300 15 N ₂ Example 4 4:5 10, 2.5 3 300 15 N ₂ Comparative Example 1 5:5 10 30 300 15 N ₂ Comparative Example 2 5:5 10 10 300 15 N ₂ Comparative Example 3 3:7 10 3 300 15 N ₂

Porosity (%) Bonding strength (MPa) Example 1 3.3 50.8 Example 2 3.7 27.6 Example 3 3.6 48.8 Example 4 5.6 41.6 Comparative Example 1 15.2 38.3 Comparative Example 2 13.2 33.3

5 is a scanning electron micrograph of a bonding member formed by the conductive bonding composition according to Example 1, and FIGS. 6 and 7 are bonding members formed by the conductive bonding composition according to Comparative Examples 1 and 2. It is a drawing showing a scanning electron microscope picture of.

Referring to Tables 1 and 2 and FIGS. 5 to 7 , the bonding member formed by the conductive bonding composition according to the examples has a smaller porosity and the bonding member is formed by the conductive bonding composition according to the comparative examples. It can be seen that the strength is large.

That is, the conductive bonding composition according to the embodiments may reduce the porosity of the bonding member formed by the low-melting-point particles by controlling the particle sizes of the high-melting-point particles (Cu) and the low-melting-point particles (Sn).

That is, in the conductive bonding composition according to the embodiments, the particle size of the low-melting-point particles is smaller than that of the high-melting-point particles, and the high-melting-point particles having a small particle diameter are disposed between the high-melting-point particles having a large particle diameter, thereby forming the low-melting-point particles. It is possible to reduce the pore size of the bonding member formed by the rapid reaction.

Accordingly, the bonding member formed by the conductive bonding composition according to the embodiments has a higher density than the bonding member formed by the conductive bonding composition according to the comparative examples, and thus may have improved bonding properties.

8 to 10 are scanning electron micrographs of a bonding member formed by the conductive bonding composition according to Examples 2 to 4, and FIG. 11 is a bonding member formed by the conductive bonding composition according to Comparative Example 3. It is a drawing showing a scanning electron microscope picture of

In addition, referring to Tables 1 and 2, and FIGS. 8 to 11, tin (Sn), a low-melting-point metal particle, reacts with copper (Cu), a high-melting-point metal particle, so that alloying and sintering of Cu6Sn5, Cu3Sn, etc. occurred can be checked

8 to 10 , it can be seen that in the bonding member formed by the conductive bonding composition according to the embodiments, Sn, which is a low-melting-point particle, does not exist as a single phase.

However, referring to FIG. 11 , it can be seen that in the bonding member formed by the conductive bonding composition according to Comparative Examples, Sn, which is a low-melting point particle, exists as a single phase.

That is, in the conductive bonding composition according to the embodiment, by controlling the ratio by weight of the high-melting-point particles to the low-melting-point particles in a certain range, it is possible to prevent the presence of the low-melting-point particles alone after firing the conductive bonding composition. .

Accordingly, the bonding member formed of the conductive bonding composition according to the embodiments may prevent a decrease in electrical properties and a decrease in strength due to the low-melting-point particles.

Preparation 2

Conductive pastes according to Examples and Comparative Examples having different weight % ratios and particle size sizes were printed on an alumina circuit board having 0.3 mm copper foil bonded to the upper and lower portions, respectively, and then dried.

Then, a gold-plated copper block with a size of 3 mm * 3 mm * 1 mm is placed on the dried conductive paste, and a pressure of 2.5 MPa to 15 MPa is applied to 300° C./30 min in nitrogen (N2) and air (Air) atmosphere. During the bonding process was carried out.

Next, the bonding strength of the bonded Cu block was measured using a die shear strength measuring device, and cross-sectional analysis was performed using SEM.

Cu:Sn
(wt% ratio) Cu particle size
(μm) Sn particle size
(μm) process temperature
(℃) process pressure
(MPa) process conditions Example 5 6:4 10, 2.5 10, 3 300 12.5 Air Example 6 6:4 10, 2.5 10, 3 300 2.5 Air Example 7 6:4 10, 2.5 10, 3 300 12.5 Air

Bonding strength (MPa) Example 5 49.6 Example 6 31.2 Example 7 43.1

Referring to Tables 3 and 4, it can be seen that the bonding members formed by the conductive bonding compositions according to the embodiments have improved bonding strength not only in a nitrogen atmosphere but also in an atmospheric atmosphere.

In addition, it can be seen that the bonding member formed of the conductive bonding composition has high bonding strength even under a low pressure condition.

That is, the conductive bonding composition according to the embodiment includes an organic vehicle having a flux component, so that the surface oxide film of the high-melting-point particles and the low-melting-point particles is removed to facilitate the alloying reaction, and an inert gas such as nitrogen It can be seen that the process is possible in the atmosphere as well as in the atmosphere.

The conductive bonding composition according to the embodiment may include a first particle having a high melting point and a second particle having a low melting point.

The conductive bonding composition according to the embodiment may increase the density of the conductive bonding composition by controlling the particle size sizes of the first particles and the second particles, and thus the electrical conductivity of the bonding member manufactured by the conductive bonding composition and strength can be improved.

In addition, the conductive bonding composition according to the embodiment may reduce the porosity of the bonding member manufactured by the conductive bonding composition by controlling the particle size of the first particle and the second particle.

Accordingly, it is possible to prevent a decrease in strength of the bonding member due to the pores of the bonding member.

In addition, the conductive bonding composition according to the embodiment controls the content range of the first particle and the second particle so that the second particle having a low melting point exists as a single phase in the bonding member manufactured by the conductive bonding composition. can be prevented

Accordingly, in the bonding member according to the embodiment, it is possible to prevent the electrical conductivity and mechanical properties of the bonding member from being deteriorated due to residual second particles having a low melting point.

Features, structures, effects, etc. described in the above-described embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to one embodiment. Furthermore, the features, structures, effects, etc. illustrated in each embodiment can be combined or modified for other embodiments by those of ordinary skill in the art to which the embodiments belong. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present invention.

In addition, although the embodiments have been described above, these are merely examples and do not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are exemplified above in a range that does not depart from the essential characteristics of the present embodiment. It can be seen that various modifications and applications that have not been made are possible. For example, each component specifically shown in the embodiments may be implemented by modification. And differences related to these modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

Claims (15)

A conductive bonding composition comprising metal particles and an organic vehicle, the composition comprising:
The metal particles include a first particle and a second particle,
The melting point of the first particle is greater than the melting point of the second particle,
At least one of the first particles and the second particles includes particles having different particle diameters,
The weight % ratio of the first particles to the second particles is 4:6 to 7:3 of the conductive bonding composition. The method of claim 1,
The first particle includes at least one metal of copper (Cu), silver (Ag), nickel (Ni), gold (Au), and aluminum (Al),
The second particle is a conductive bonding composition comprising at least one metal of tin (Sn), zinc (Zn), indium (In), and gallium (Ga). The method of claim 1,
The first particle is included in an amount of 20 wt% to 70 wt% based on the total of the conductive bonding composition,
The second particle is included in an amount of 20% by weight to 60% by weight based on the total amount of the conductive bonding composition. The method of claim 1,
The conductive bonding composition of the first particle having a particle diameter of 0.1 μm to 30 μm. 5. The method of claim 4,
The first particle is a conductive bonding composition comprising 1-1 particles and 1-2 particles having different particle diameters. 6. The method of claim 5,
The particle diameter of the 1-1 particles is larger than the particle diameter of the first 1-2 particles,
A ratio of the particle diameter of the 1-1 particle to the particle diameter of the first 1-2 particle is 2:1 to 10:1. 5. The method of claim 4,
The particle diameter of the second particle is smaller than the particle diameter of the first particle conductive bonding composition. 8. The method of claim 7,
The particle diameter of the second particle is 50% or less of the particle diameter of the first particle conductive bonding composition. 7. The method of claim 4 or 6,
The second particle is a conductive bonding composition comprising 2-1 particles and 2-2 particles having different particle diameters. 10. The method of claim 9,
The particle diameter of the 2-1 particle is larger than the particle diameter of the 2-2 particle,
The particle diameter of the 2-1 particle is more than 50% to 100% of the particle diameter of the first particle,
The particle diameter of the second particle 2-2 is 50% or less of the particle diameter of the first particle conductive bonding composition. Board;
a circuit pattern disposed on the substrate; and
a chip disposed on the circuit pattern;
A bonding member is disposed between the circuit pattern and the chip,
The bonding member is
A conductive bonding composition comprising metal particles and an organic vehicle, the composition comprising:
The metal particles include a first particle and a second particle,
The melting point of the first particle is greater than the melting point of the second particle,
At least one of the first particles and the second particles includes particles having different particle diameters,
The weight % ratio of the first particles to the second particles is 4:6 to 7:3 of the electronic component. 12. The method of claim 11,
The first particle has a particle diameter of 0.1 μm to 30 μm. 13. The method of claim 12,
The first particles include 1-1 particles and 1-2 particles having different particle diameters,
The particle diameter of the 1-1 particles is larger than the particle diameter of the first 1-2 particles,
The ratio of the particle diameter of the 1-1 particle to the particle diameter of the 1-2 particle is 2:1 to 10:1. 13. The method of claim 12,
The particle diameter of the second particle is 50% or less of the particle diameter of the first particle. 14. The method of claim 12 or 13,
The second particle is an electronic component including a 2-1 particle and a 2-2 particle having different particle diameters.

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