Silver complex for die attach paste, and preparation method therefor

Abstract

Disclosed are a silver complex for a die attach paste, and a preparation method therefor, the silver complex being added to a die attach paste so as to improve low-temperature sintering, high electrical conductivity and high thermal conductivity characteristics. According to the present invention, the silver complex for a die attach paste, which is prepared through a chemical reaction using ionic bonding, is added to a die attach paste, thereby improving semiconductor properties of the die attach paste. The silver complex for a die attach paste, according to the present invention, can be prepared by a method for preparing a silver complex for a die attach paste, the method comprising the steps of: dissolving a silver precursor in a solvent so as to prepare a silver precursor solution; dissolving an alkyl chain-based organic material in a solvent and ionizing same; mixing the silver precursor solution and the ionized alkyl chain-based organic material so as to produce a silver complex; and purifying same in order to obtain a high-purity silver complex. The silver complex according to the present invention is: added to a die attach paste so as to improve die adhesion strength and thermal conductivity characteristics; and added to a die attach paste so that the die attach paste can be sintered at a low temperature of 200 °C or lower.

Description

Silver complex for die attach paste and method for manufacturing the same

[0001] This invention was obtained as a result of the research conducted under the 2024 project [Development and Demonstration of High-Thermal Conductivity Paste Sintering Bonding Technology for WBG Power Semiconductor Die Bonding Using Highly Dispersible Silver Complex Nanofiller Materials], funded by the government (Ministry of Science and ICT) in 2024. (Project Unique ID: 2710006492; Project No.: RS-2024-00428299)

[0002] The present invention relates to a silver complex containing silver ions in an organic substrate that can be used in die attach paste, and a method for manufacturing the same. Specifically, it relates to a silver complex in which silver (Ag) is ionicly bonded to an alkyl chain-based organic material that contributes to low-temperature sintering of the die attach paste, and a method for manufacturing the same.

[0003] The individual squares that make up a semiconductor wafer are called dies. Semiconductor packages are fabricated by bonding dies to a substrate, DBC (direct bonding copper), and AMB (active metal brazing) using die attach paste.

[0004] In this regard, semiconductor die attach materials must fundamentally possess high adhesion and high thermal conductivity, and must also be commercially processable and price-competitive.

[0005] Silver paste is mainly used as a semiconductor die attach material.

[0006] In order for silver paste to fully exhibit its properties as a die attach material, the silver paste must satisfy high sintering density characteristics after the heat treatment process, and the heat treatment temperature must be low.

[0007] The higher the heat treatment temperature, the easier it is for silver nanoparticles to melt, resulting in a high sintering density, but there are problems such as cracking and peeling of the die attach paste layer due to warpage caused by thermal deformation of the substrate.

[0008] To solve these problems, research is being conducted on the production of pastes capable of low-temperature sintering by using methods such as using silver flake-shaped particles, using silver nanoparticle-shaped particles, and using silver oxide.

[0009] In the case of using silver flake-shaped particles, the thin thickness allows for a lower melting temperature of the silver particles. However, it has the disadvantage that it is difficult to disperse the silver particles evenly, and the size of the silver particles is not uniform, making it unsuitable for low-temperature sintering.

[0010] In the case of using particles in the form of silver nanoparticles, low-temperature sintering is possible due to the high specific surface area and nano-scale size, but there is a disadvantage that printing processes are impossible due to high viscosity when used in die attach paste containing a high concentration of silver.

[0011] In the case of the method using silver oxide, it can be applied to silver paste using silver coated with organic material to improve the dispersibility of silver nanoparticles. This is because silver oxide is activated at low temperatures, which lowers the decomposition temperature of the coated organic material. However, since the decomposed organic material vaporizes into a gaseous form, problems such as voids may occur after the heat treatment process.

[0012] Therefore, there is a need to develop a material that can be added to conventional semiconductor die attach pastes to enable sintering even at low temperatures and exhibit excellent characteristics such as high adhesive strength and thermal conductivity after the heat treatment process.

[0013] The object of the present invention is to provide a method for manufacturing a silver complex for die attach paste.

[0014] In addition, the objective of the present invention is to provide a method for manufacturing a silver complex for die attach paste that can control the sintering temperature of the silver complex according to the number of carbon atoms of the ligand during the process of manufacturing the silver complex.

[0015] In addition, the objective of the present invention is to provide a silver complex that can be added to a conventional semiconductor die attach paste.

[0016] In addition, the objective of the present invention is to provide a silver complex for die attach paste that is added to the die attach paste to improve die adhesion strength and thermal conductivity characteristics.

[0017] In addition, the objective of the present invention is to provide a die-attach complex compound that can be added to a die-attach paste and enabled to be sintered at low temperature.

[0018] The objects of the present invention are not limited to those mentioned above, and other unmentioned objects and advantages of the present invention may be understood from the following description and will be more clearly understood by the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0019] To solve the above problem, the present invention,

[0020] The present invention provides a silver complex for die-attach paste formed by the ionic bonding of silver ions of a silver (Ag) precursor and ionized alkyl chain organic compounds.

[0021] Herein, the silver complex for die attach paste is provided, characterized in that the silver precursor comprises one or more selected from the group consisting of silver acetate, silver nitrate, silver pentafluoropropionate, silver phosphate, and silver carbonate.

[0022] In addition, the present invention provides a silver complex for die attach paste characterized in that the ionized alkyl chain-based organic material comprises one or more selected from the group consisting of dodecylamine, oleylamine, oleic acid, octadecylamine, hexadecylamine, polyethylamine, hexanoic acid, decanoic acid, neodecanoic acid, ethylhexanoic acid, lauric acid, benzoic acid, and octadecanoic acid.

[0023] Furthermore, the present invention provides a silver complex for die attach paste characterized in that the carbon number of the ionized alkyl chain-based organic compound is 10 to 12.

[0024] In addition, a silver complex for die attach paste is provided, characterized in that the molar ratio of the silver precursor to the ionized alkyl chain-based organic compound is 1:1 to 1:3.

[0025] Meanwhile, a die attach paste comprising a silver complex for the die attach paste is provided.

[0026] In addition, the present invention provides a method for preparing a silver complex for die attach paste, comprising the steps of: dissolving a silver precursor in a solvent to prepare a silver precursor solution; dissolving an alkyl chain-based organic material in a solvent to ionize it; and mixing the silver precursor solution with the ionized alkyl chain-based organic material to produce a silver complex.

[0027] Herein, a method for manufacturing a silver complex for die attach paste is provided, characterized by additionally including a step of purifying the generated silver complex.

[0028] In addition, the present invention provides a method for preparing a silver complex for die attach paste, characterized in that the solvent for dissolving the silver precursor comprises one or more selected from the group consisting of toluene, hexane, xylene, benzene, cyclohexane, ethylbenzene, chlorobenzene, dichlorobenzene, trichlorobenzene, chloroform, purified water (DI-water), ethanol, methanol, and isopropyl alcohol.

[0029] In addition, the present invention provides a method for preparing a silver complex for die attach paste, characterized in that the solvent for dissolving the alkyl chain-based organic compound comprises one or more selected from the group consisting of lithium hydroxide (LiOH), sodium hydroxide (NaOH), potassium hydroxide (KOH), rubidium hydroxide (RbOH), cesium hydroxide (CsOH), calcium hydroxide (Ca(OH)2), barium hydroxide (Ba(OH)2), and strontium hydroxide (Sr(OH)2).

[0030] According to the present invention, a silver complex for die attach paste prepared through a chemical reaction using ionic bonding can be added to the die attach paste to help with low-temperature sintering of the die attach paste.

[0031] Accordingly, a heat treatment process for silver sintering at low temperatures may be possible, and thermal deformation of the substrate may be prevented, thereby preventing cracking and peeling of the die attach paste layer.

[0032] According to the present invention, there is an advantage in that the sintering temperature of the silver complex can be controlled according to the number of carbon atoms of the ligand during the process of manufacturing the silver complex.

[0033] According to the present invention, a silver complex is added to the die attach paste to improve die adhesion strength and thermal conductivity characteristics.

[0034] According to the present invention, a silver complex is added to the die attach paste, and the die attach paste has the advantage of being able to be sintered at a low temperature of 200°C or lower.

[0035] In addition to the effects described above, the specific effects of the present invention are described together with the specific details for implementing the invention below.

[0036] FIG. 1 is a flowchart illustrating a method for preparing a silver complex for die attach paste according to the present invention.

[0037] FIG. 2 is a schematic diagram of a reaction for preparing a silver complex for die attach paste according to the present invention.

[0038] Figure 3 shows the 1700 cm⁻¹ observed in the silver precursor through Fourier transform infrared spectroscopy (FT-IR) analysis. -1 It is an observation of the change in COOH bonding emerging from the peak.

[0039] Figure 4 shows actual photographs of the synthesized silver complex for die attach paste with and without purification. The left photograph shows a perfectly purified silver complex for die attach paste, and the right photograph shows a silver complex for die attach paste with insufficient purification.

[0040] Figure 5 shows the thermal decomposition temperature of the silver complex for the synthesized die attach paste, confirmed through differential scanning calorimetry (DSC) analysis.

[0041] Figure 6 is a table summarizing the characteristics of die-attach paste by adding a silver complex for die-attach paste according to the number of carbon atoms in the examples.

[0042] Figure 7 is a table summarizing the characteristics of the die attach paste according to the order of addition of the die attach paste in the example.

[0043] The aforementioned objectives, features, and advantages are described in detail below with reference to the attached drawings, thereby enabling those skilled in the art to easily implement the technical concept of the present invention. In describing the present invention, detailed descriptions of known technologies related to the present invention are omitted if it is determined that such descriptions would unnecessarily obscure the essence of the invention. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0044] In the following, the statement that any configuration is placed on the "upper (or lower)" of a component or on the "upper (or lower)" of a component may mean not only that any configuration is placed in contact with the upper (or lower) surface of said component, but also that another configuration may be interposed between said component and any configuration placed on (or below) said component.

[0045] In addition, where it is stated that one component is "connected," "combined," or "connected" to another component, it should be understood that while the components may be directly connected or connected to each other, another component may be "interposed" between each component, or each component may be "connected," "combined," or "connected" through another component.

[0046] Hereinafter, a silver complex for die attachment and a method for manufacturing the same according to some embodiments of the present invention will be described.

[0047] The silver (Ag) complex for die attach paste of the present invention is a material that can be added to conventional silver paste, and is a silver complex in which silver ions and ionized organic matter are ionically bonded, and has the effect of enabling low-temperature sintering of the die attach paste.

[0048] FIG. 1 is a flowchart showing a method for preparing a silver complex for die attach paste according to the present invention, and FIG. 2 is a schematic diagram of a reaction for preparing a silver complex for die attach paste.

[0049] Referring to FIGS. 1 and 2, a method for preparing a silver complex for die attach paste comprises the steps of: dissolving a silver precursor in a solvent to prepare a silver precursor solution (S101); dissolving an alkyl chain-based organic material in a solvent to ionize it (S102); mixing the silver precursor solution with the ionized alkyl chain-based organic material to produce a silver complex (S103); and purifying the silver complex to obtain a high-purity silver complex (S104).

[0050] The present invention is a silver complex that can be used in die attach paste and contains silver ions in an organic substrate, and is a silver complex in which silver is ionicly bonded to an alkyl chain-based organic material that contributes to low-temperature sintering of the die attach paste.

[0051] A silver complex is prepared by ionic bonding through a chemical reaction between a silver precursor and an alkyl chain-based organic compound.

[0052] For a silver precursor to form an ionic bond with an alkyl chain-based organic compound, silver ions must be generated from the silver precursor, and the alkyl chain-based organic compound must be ionized. The silver precursor is dissolved in a solvent to form silver ions, and the alkyl chain-based organic compound is reacted with a strong basic substance to ionize the organic compound and proceed with the chemical reaction. The alkyl chain-based organic compound, which is bound to the strong base, moves due to the difference in electronegativity of the metal ion to form a new bond. If the metal ion constituting the strong base has lower electronegativity than the silver ion, the electronegative silver ion exerts a stronger attractive force toward the silver ion, causing the ionized organic compound to form an ionic bond with the silver ion. Through this process, a silver complex can be prepared. Complex compounds, also referred to as coordination compounds or complex ions, can represent a form in which a ligand is bound to a metal ion.

[0053] A silver precursor solution is a state in which the silver precursor is dissolved in a solvent.

[0054] The silver precursor may be selected from the group consisting of silver acetate, silver nitrate, silver pentafluoropropionate, silver phosphate, and silver carbonate, but is not limited thereto.

[0055] The silver precursor solution is in a state where the silver precursor is dissolved in a solvent, and the solvent may include, but is not limited to, one or more of toluene, hexane, xylene, benzene, cyclohexane, ethylbenzene, chlorobenzene, dichlorobenzene, trichlorobenzene, chloroform, purified water (DI-water), ethanol, methanol, and isopropyl alcohol.

[0056] The organic material that chemically reacts with the precursor solution may be a ligand having a long alkyl chain, and may include a relatively nonpolar ligand with a different decomposition temperature depending on the number of carbons. The ligand may include one or more of dodecylamine, oleylamine, oleic acid, octadecylamine, hexadecylamine, polyethylamine, hexanoic acid, decanoic acid, neodecanoic acid, ethylhexanoic acid, lauric acid, benzoic acid, and octadecanoic acid, but is not limited thereto.

[0057] A strong basic organic compound may be included to ionize an organic compound having a strongly nonpolar ligand. The strong basic organic compound may include one or more of lithium hydroxide (LiOH), sodium hydroxide (NaOH), potassium hydroxide (KOH), rubidium hydroxide (RbOH), cesium hydroxide (CsOH), calcium hydroxide (Ca(OH)2), barium hydroxide (Ba(OH)2), and strontium hydroxide (Sr(OH)2), but is not limited thereto.

[0058] The amino group (-NH2) or / and hydroxyl group (-OH) is ionized by a strong basic organic compound and can be converted into an amide or / and acetate to bind with the silver ions of the silver precursor.

[0059] The silver precursor and the ionized organic material can be mixed in a molar ratio of 1:1 to 1:3, preferably 1:1.5 to 1:2.5, and more preferably 1:2 to 1:2.5.

[0060] If the ratio of ionized organic matter is less than 1, the number of bonds between the silver precursor and the ionized organic matter does not match, which may result in a smaller yield. Conversely, if the ratio of ionized organic matter exceeds 3, a large amount of unreacted material is produced, which may prolong the purification process time or lower the properties due to the unreacted material.

[0061] When ionized organic matter is added to a silver precursor solution, due to the difference in electronegativity between the strong base metal and silver, the organic matter bound to the weak base metal moves to the silver ion and forms an ionic bond.

[0062] Referring to Figure 3, this graph shows the results of Fourier Transform Infrared Spectroscopy (FT-IR) analysis to confirm the chemical bonding of the synthesized silver complex. The precursor of the example has a COOH functional group. Along with the degassing of COOH, the silver and the ligand form an ionic bond through the binding of the alkyl chain ligand. Therefore, in the silver complex, the C=O peak constituting COOH (1700 cm⁻¹) -1 ) disappears and Ag + The COO combining with - Peak (1500 cm) -1 It can be seen that ) is generated.

[0063] In the process of preparing a silver complex for die attach paste, the temperature of the solution during the reaction is preferably around 60 to 70°C, and the reaction time can be 1 to 2 hours.

[0064] For washing the silver complex for die attach paste, purified water and ethanol can be used, and the silver complex for die attach paste precipitated in the purified water and ethanol solution can be separated using a membrane filter.

[0065] Figure 4 shows an actual photograph of the synthesized silver complex for die attach paste. A silver complex for die attach paste that has been perfectly purified using purified water and ethanol can yield a white solid. However, due to an insufficient purification process, additional reactions occur between the metal of the strong base and the organic material caused by the presence of a strong base, resulting in the silver complex turning brown and becoming unusable.

[0066] The synthesized silver complex for die attach paste is prepared through a chemical reaction of ligands based on electronegativity, and since the decomposition temperature can be controlled according to the ligands, it is added to the die attach paste described later to improve high sintering density, high electrical conductivity, high adhesive strength, and high thermal conductivity characteristics.

[0067] Referring to Figure 5, thermal analysis was performed using differential scanning calorimetry (DSC) to confirm the temperature-dependent phase transition of the synthesized silver complex for die attach paste. It was confirmed that the decomposition temperature of silver ions and ligands occurs at approximately 108°C, and silver nanoparticles are formed through the aggregation of silver ions generated by heat. Accordingly, when added to the die attach paste, the silver complex forms silver nanoparticles through a heat treatment process, and sintering begins at a low temperature as it acts as a bridge connecting the silver nanoparticles, thereby increasing electrical and thermal conductivity.

[0068] As such, since the silver complex for die attach paste enables low-temperature sintering, it can be added to the die attach paste described later to enable low-temperature sintering and has the effect of improving adhesive strength, electrical conductivity, and thermal conductivity properties.

[0069] [Example]

[0070] In FIGS. 6 and 7 below, Example 1, Example 2, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4 are as follows.

[0071] [Example 1]

[0072] Add 40 mL of water and 0.25 mol of silver acetate to a 250 mL 1-neck flask and stir (silver precursor solution). Add 40 mL of a solvent with a 12-carbon decanoic acid ratio of 0.30 mol and ethanol to water ratio of 1:1 to a 250 mL beaker and stir (organic solution). Add a strong basic substance (0.40 mol) to the organic solution and stir for 1 hour. Add the organic solution to the silver precursor solution and stir at 70°C for 2 hours. Purify by adding the silver complex solution to a solvent mixture of acetone and purified water in a 1:1 volume ratio. After filtering, dry in a vacuum oven.

[0073] Next, a die attach paste is prepared by adding a silver complex for the die attach paste synthesized as shown in Table 1. The die attach paste consists of silver powder, a silver complex, epoxy, a curing agent, a catalyst, a solvent, and a dispersant, and the detailed manufacturing method is omitted.

[0074] [Example 2]

[0075] A silver complex was prepared using an organic material having 10 carbon atoms, and a die attach paste was prepared using the same process as in Example 1, so the detailed manufacturing method is omitted.

[0076] Looking at Table 1, the viscosity, bonding strength after heat treatment, C-SAM, thermal conductivity, and sintering density of the manufactured die attach paste were confirmed. Detailed methods for evaluating physical properties are described later.

[0077] To control the decomposition temperature of silver complexes, silver complexes were synthesized according to the number of carbon atoms, and as the number of carbon atoms increased, the decomposition temperature of the organic ligands increased from 97°C to 162°C. Notably, aromatic organic ligands exhibited high decomposition temperatures despite having a small number of carbon atoms.

[0078] As the number of carbon atoms in the added silver complex increases, the solubility in the solvent increases, so the viscosity of the die attach paste decreased from 28,000 cPs to 15,000 cPs.

[0079] After die bonding, heat treatment was performed at 200°C to verify the adhesion of the die attach paste. As described in Comparative Example 4, the conventional die attach paste could not measure bonding strength, C-SAM, and thermal conductivity at 200°C due to the non-attachment of the die caused by the non-crystallization of silver.

[0080] Looking at Examples 1 and 2, when the number of carbon atoms in the silver complex was 10 to 12, it exhibited high adhesive strength (30 to 27 MPa) and no void or delamination phenomena occurred. In addition, high thermal conductivity (200 W / mK to 220 W / mK) and high sintering density results were obtained.

[0081] Looking at Comparative Example 1, when the number of carbon atoms in the silver complex was 12 or more or 10 or less, specifically when the number of carbon atoms was 14, many void phenomena occurred due to ligands vaporizing during the heat treatment process, and even if heat treatment was carried out at a temperature higher than the decomposition temperature of the silver complex with added paste, unsolidified silver powder was observed because it was difficult to decompose due to heat absorption by the various materials constituting the paste.

[0082] Looking at Comparative Example 2, when the number of carbon atoms was 6, the highest sintering density was observed due to the low ligand decomposition temperature, but due to low solubility, it was difficult to proceed with the printing process with a high viscosity value (38,000 cPs) when applied to paste. Therefore, a void phenomenon was observed, and low bonding strength (12 MPa) and low thermal conductivity (60 W / mK) values ​​were exhibited.

[0083] Looking at Comparative Example 3, when an aromatic silver complex with 6 carbon atoms was added to the die attach paste, a high viscosity (49,000 cPs) and a high decomposition temperature (240℃) resulted in low bonding strength (2 MPa), void occurrence, and a non-crystallized form.

[0084] Looking at Table 2, in order to confirm the effect of improving semiconductor characteristics when the silver complex for die attach paste is added to the manufactured die attach paste rather than when the silver complex for die attach paste is added during the manufacturing of the die attach paste, the semiconductor characteristics were checked for the case where the silver complex for die attach paste is added during the manufacturing of the die attach paste and the case where the silver complex for die attach paste is added to the manufactured die attach paste.

[0085] However, when adding a silver complex for die attach paste to the manufactured die attach paste, it was added after dissolving it in a solvent at a ratio of 0.3 wt%.

[0086] Due to the die attach paste added after dissolution in a solvent, a lower viscosity value (23,000 cPs → 21,000 cPs) than the existing die attach paste was obtained, and similar bonding strength (30 MPa → 31 MPa) and thermal conductivity (220 W / mK → 230 W / mK) values ​​can be obtained.

[0087] Accordingly, in the case of silver complexes for die attach paste, semiconductor properties can be easily improved simply by adding them to the manufactured die attach paste.

[0088] Physical property evaluation methods and evaluation results

[0089] 1) Thermal conductivity: A sample for measuring thermal conductivity was prepared by casting the manufactured chip bonding composition to a diameter of 12.5 mm and a thickness of 2 mm, and then coated with graphite.

[0090] Thermal diffusivity was measured using LFA (laser flash analysis) equipment and calculated using the formula λ (thermal conductivity) = a (thermal diffusivity) × Cp (specific heat) × ρ (density).

[0091] 2) Chip bonding strength: A sample for measurement was prepared by dispensing the prepared chip bonding composition onto a silver-plated copper substrate, placing a 5.0 mm x 5.0 mm SiC chip on top of it, and heat-treating at 200°C. Shear strength was measured at room temperature using a die shear tester (ROYCE).

[0092] The evaluation results are as described in Figures 6 and 7.

[0093] As described in FIGS. 6 and 7, the silver complex of the example, to which an alkyl chain-based organic material having a controlled number of carbon atoms is applied, was found to enable low-temperature sintering of the die attach paste containing it and to achieve excellent adhesive strength and thermal conductivity after sintering.

[0094] On the other hand, it was confirmed that the silver complex of the comparative example, to which an alkyl chain-based organic material having an out-of-range number of carbon atoms was applied, showed a significant decrease in adhesive strength or thermal conductivity during low-temperature sintering of the die attach paste containing it.

[0095] Although the present invention has been described above with reference to the illustrated drawings, the present invention is not limited by the embodiments and drawings disclosed in this specification, and it is obvious that various modifications can be made by a person skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration according to the present invention were not explicitly described while explaining the embodiments of the present invention above, it is natural to acknowledge that the effects predictable by said configuration should also be recognized.

Claims

1. A silver complex for die-attach paste formed by the ionic bonding of silver ions of a silver (Ag) precursor and ionized alkyl chain organic compounds.

2. In Paragraph 1, A silver complex for die attach paste, characterized in that the above silver precursor comprises one or more selected from the group consisting of silver acetate, silver nitrate, silver pentafluoropropionate, silver phosphate, and silver carbonate.

3. In Paragraph 1, A silver complex for die attach paste, characterized in that the above-mentioned ionized alkyl chain-based organic material comprises one or more selected from the group consisting of dodecylamine, oleylamine, oleic acid, octadecylamine, hexadecylamine, polyethylamine, hexanoic acid, decanoic acid, neodecanoic acid, ethylhexanoic acid, lauric acid, benzoic acid, and octadecanoic acid, which are ionized.

4. In Paragraph 3, A silver complex for die-attach paste, characterized in that the carbon number of the ionized alkyl chain-based organic compound is 10 to 12.

5. In any one of paragraphs 1 through 4, A silver complex for die attach paste, characterized in that the molar ratio of the silver precursor to the ionized alkyl chain-based organic compound is 1:1 to 1:

3.

6. A die attach paste comprising a silver complex of the die attach paste of claim 5.

7. A step of preparing a silver precursor solution by dissolving a silver precursor in a solvent; A step of dissolving an alkyl chain-based organic in a solvent to ionize it; and A method for preparing a silver complex for die attach paste, comprising the step of mixing a silver precursor solution with an ionized alkyl chain-based organic material to produce a silver complex.

8. In Paragraph 7, A method for manufacturing a silver complex for die attach paste, characterized by additionally including a step of purifying the generated silver complex.

9. In Paragraph 7, A method for manufacturing a die attach paste, characterized in that the solvent for dissolving the above silver precursor comprises one or more selected from the group consisting of toluene, hexane, xylene, benzene, cyclohexane, ethylbenzene, chlorobenzene, dichlorobenzene, trichlorobenzene, chloroform, purified water (DI-water), ethanol, methanol, and isopropyl alcohol.

10. In Paragraph 7, A method for manufacturing a die attach paste, characterized in that the solvent for dissolving the above-mentioned alkyl chain-based organic material comprises one or more selected from the group consisting of lithium hydroxide (LiOH), sodium hydroxide (NaOH), potassium hydroxide (KOH), rubidium hydroxide (RbOH), cesium hydroxide (CsOH), calcium hydroxide (Ca(OH)2), barium hydroxide (Ba(OH)2), and strontium hydroxide (Sr(OH)2).

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