Classification and application areas of conductive silver paste
In the electronics industry, conductive silver paste is used in a large number of applications due to its excellent conductivity and good printing adaptability, is a combination of metallic materials, non-metallic materials, polymer materials and other products. Usually used in conductive LED, LCD, TR, IC, COB, MLCC, EL cold light sheet, touch screen, display, solar photovoltaic, liquid crystal module, piezoelectric crystals, piezoelectric ceramics, integrated circuits, electronic components, circuit boards, lighting, 5G mobile communications, computers, cell phones, automotive electronics, smart cards, RFID, electronic tags, potentiometers, detectors, heating, intelligent heating and smart antennas. wearable and smart antenna, etc. to realize the electrical connection between electronic components.
Conductive silver paste is mainly composed of silver powder, binder, solvent and other functional additives. Silver powder is the key component of conductive silver paste, and its purity and particle size directly affect the conductivity of the product. The binder is used to fix the silver powder on the surface of the substrate, while the solvent helps the paste maintain proper fluidity during the printing process. In addition, according to specific application requirements, dispersants, thickeners and other auxiliary components may be added to improve the processing performance of the paste.
Classification of conductive silver paste
1. According to the use of conductive silver paste, it can be divided into electronic conductive silver paste and photoelectric conductive silver paste. Electronic conductive silver paste is mainly used in the manufacture of electronic devices, such as printed circuit boards (PCB), integrated circuits, multilayer ceramic capacitors (MLCC) internal electrodes, semiconductor packages, etc., more concerned about the material's durability, adhesion and process compatibility, the requirements of excellent electrical conductivity, low electrical resistivity, for circuit connection and signal transmission. Optoelectronic conductive silver paste is mainly used for high conductivity, high reliability and fine grid precision photovoltaic cells or photovoltaic display field, such as solar cells, OLED display electrodes, photoelectric sensors. Photoelectric conductive silver paste has a high light absorption and photoelectric conversion efficiency to maximize the electrical energy or photoelectric conversion efficiency, can effectively improve the performance of optoelectronic devices, pay more attention to the silver paste of light transmission, weathering and bonding with transparent substrates.
2. According to the sintering temperature of conductive silver paste, it can be categorized into high temperature silver paste, medium temperature silver paste, and low temperature silver paste. Low-temperature silver paste sintering temperature of 150 ° C - 500 ° C, suitable for low-temperature processing, the substrate is not easy to heat damage, commonly used in flexible electronics and low-temperature substrates (such as plastics, glass), in the RFID antenna, touch-screen conductive lines, flexible circuits, displays, electrodes, and other fields of wide application. Medium temperature silver paste sintering temperature of 500 ° C - 800 ° C, can be both high conductivity and moderate processing temperature, usually in the air sintering, the process is relatively simple. Widely used in MLCC internal electrode, photovoltaic battery electrode printing, PCB local conductive path and other fields. High-temperature silver paste sintering temperature of 800 ° C - 950 ° C, excellent conductivity, low resistivity and high temperature resistance, sintered with ceramic or metal substrate combination of strong, but need to be sintered in a vacuum or reducing atmosphere to avoid oxidation. Widely used in IGBT modules, circuit substrates (such as DCB), packaging of high-power devices, suitable for alumina (Al₂O₃), aluminum nitride (AlN) and other ceramic substrates.
3. According to the type of substrate, conductive silver powder can be divided into metal-based silver paste, ceramic-based silver paste and flexible substrate silver paste. Metal-based silver paste for copper, aluminum, molybdenum and other metal substrates, need to consider matching the coefficient of thermal expansion with the substrate, such as power module packaging. Ceramic-based silver paste is suitable for ceramic substrates such as Al₂O₃, AlN, etc. It is used in high-power electronic device substrates, electrodes and other products. Flexible substrate silver paste is suitable for PET, PI and other flexible substrates, which can be applied to RFID, flexible electronics, touch screen and other fields.
Application areas of conductive silver paste
1, the field of electronics: Ag has been developed as an interconnect material for power electronics packaging, silver paste has been widely studied as an interconnect material due to its excellent electrical and thermal conductivity, and has been applied to LED packaging, power electronics, etc..
(1) Printed Circuit Board (PCB): In the PCB manufacturing process, conductive silver paste is often used to make fine lines or to realize the conductive connection of special areas. Compared with traditional welding methods, the use of conductive silver paste can simplify the production process and reduce costs.
(2) Sintered Ag joints as a chip bonding material in microelectronic packaging, in terms of shear strength, thermal fatigue and creep properties, etc. have better thermal and mechanical properties than traditional lead-based solder.
(3) touch screen: in the manufacture of touch screens, conductive silver paste is used to form a transparent conductive film, enabling the screen to sense changes in the position of the finger or stylus to achieve interactive operation.
(4) radio frequency identification (RFID) tags: in the RFID tag antenna manufacturing
(7) applied to LTCC (Low Temperature Co-fired Ceramics) technology, the production of ceramic materials sintered into the substrate at a temperature of 900 ° C or less, can be used as a highly conductive, low melting point of gold, silver, copper and other materials as a conductor, LTCC products have a wide range of applications, are often used in high-frequency areas, such as wireless communications, automotive electronics, aviation and so on.
2、Photovoltaic field: In the production of front electrodes for solar panels, conductive silver paste plays a vital role. Through precise printing, a conductive grid can be formed on the surface of the silicon wafer, effectively collecting the current generated by photovoltaic conversion.
In photovoltaic cell applications, silver powder is a key material in the preparation of photovoltaic silver pastes, and the easy dispersion and high packing density of spherical ultrafine silver powder help to improve the photovoltaic cell's photoelectric conversion efficiency and stability. With the development of electronic equipment in the direction of smaller, thinner and smarter, the requirements for conductive silver paste are getting higher and higher. The future of conductive silver paste should not only have a higher conductivity and better adhesion, but also need to have better flexibility and lower cost. In addition, the research and development of environmentally friendly conductive silver paste has also become one of the industry's focus.
In short, conductive silver paste as an indispensable basic material in the electronics industry, its performance optimization and technological innovation will directly affect the progress and development of the industry as a whole. With the application of continuous updating progress, we have reason to expect that the conductive silver paste in the future will have a wider range of application prospects.
Conductive silver paste is mainly composed of silver powder, binder, solvent and other functional additives. Silver powder is the key component of conductive silver paste, and its purity and particle size directly affect the conductivity of the product. The binder is used to fix the silver powder on the surface of the substrate, while the solvent helps the paste maintain proper fluidity during the printing process. In addition, according to specific application requirements, dispersants, thickeners and other auxiliary components may be added to improve the processing performance of the paste.
Classification of conductive silver paste
1. According to the use of conductive silver paste, it can be divided into electronic conductive silver paste and photoelectric conductive silver paste. Electronic conductive silver paste is mainly used in the manufacture of electronic devices, such as printed circuit boards (PCB), integrated circuits, multilayer ceramic capacitors (MLCC) internal electrodes, semiconductor packages, etc., more concerned about the material's durability, adhesion and process compatibility, the requirements of excellent electrical conductivity, low electrical resistivity, for circuit connection and signal transmission. Optoelectronic conductive silver paste is mainly used for high conductivity, high reliability and fine grid precision photovoltaic cells or photovoltaic display field, such as solar cells, OLED display electrodes, photoelectric sensors. Photoelectric conductive silver paste has a high light absorption and photoelectric conversion efficiency to maximize the electrical energy or photoelectric conversion efficiency, can effectively improve the performance of optoelectronic devices, pay more attention to the silver paste of light transmission, weathering and bonding with transparent substrates.
2. According to the sintering temperature of conductive silver paste, it can be categorized into high temperature silver paste, medium temperature silver paste, and low temperature silver paste. Low-temperature silver paste sintering temperature of 150 ° C - 500 ° C, suitable for low-temperature processing, the substrate is not easy to heat damage, commonly used in flexible electronics and low-temperature substrates (such as plastics, glass), in the RFID antenna, touch-screen conductive lines, flexible circuits, displays, electrodes, and other fields of wide application. Medium temperature silver paste sintering temperature of 500 ° C - 800 ° C, can be both high conductivity and moderate processing temperature, usually in the air sintering, the process is relatively simple. Widely used in MLCC internal electrode, photovoltaic battery electrode printing, PCB local conductive path and other fields. High-temperature silver paste sintering temperature of 800 ° C - 950 ° C, excellent conductivity, low resistivity and high temperature resistance, sintered with ceramic or metal substrate combination of strong, but need to be sintered in a vacuum or reducing atmosphere to avoid oxidation. Widely used in IGBT modules, circuit substrates (such as DCB), packaging of high-power devices, suitable for alumina (Al₂O₃), aluminum nitride (AlN) and other ceramic substrates.
3. According to the type of substrate, conductive silver powder can be divided into metal-based silver paste, ceramic-based silver paste and flexible substrate silver paste. Metal-based silver paste for copper, aluminum, molybdenum and other metal substrates, need to consider matching the coefficient of thermal expansion with the substrate, such as power module packaging. Ceramic-based silver paste is suitable for ceramic substrates such as Al₂O₃, AlN, etc. It is used in high-power electronic device substrates, electrodes and other products. Flexible substrate silver paste is suitable for PET, PI and other flexible substrates, which can be applied to RFID, flexible electronics, touch screen and other fields.
Application areas of conductive silver paste
1, the field of electronics: Ag has been developed as an interconnect material for power electronics packaging, silver paste has been widely studied as an interconnect material due to its excellent electrical and thermal conductivity, and has been applied to LED packaging, power electronics, etc..
(1) Printed Circuit Board (PCB): In the PCB manufacturing process, conductive silver paste is often used to make fine lines or to realize the conductive connection of special areas. Compared with traditional welding methods, the use of conductive silver paste can simplify the production process and reduce costs.
(2) Sintered Ag joints as a chip bonding material in microelectronic packaging, in terms of shear strength, thermal fatigue and creep properties, etc. have better thermal and mechanical properties than traditional lead-based solder.
(3) touch screen: in the manufacture of touch screens, conductive silver paste is used to form a transparent conductive film, enabling the screen to sense changes in the position of the finger or stylus to achieve interactive operation.
(4) radio frequency identification (RFID) tags: in the RFID tag antenna manufacturing
(7) applied to LTCC (Low Temperature Co-fired Ceramics) technology, the production of ceramic materials sintered into the substrate at a temperature of 900 ° C or less, can be used as a highly conductive, low melting point of gold, silver, copper and other materials as a conductor, LTCC products have a wide range of applications, are often used in high-frequency areas, such as wireless communications, automotive electronics, aviation and so on.
2、Photovoltaic field: In the production of front electrodes for solar panels, conductive silver paste plays a vital role. Through precise printing, a conductive grid can be formed on the surface of the silicon wafer, effectively collecting the current generated by photovoltaic conversion.
In photovoltaic cell applications, silver powder is a key material in the preparation of photovoltaic silver pastes, and the easy dispersion and high packing density of spherical ultrafine silver powder help to improve the photovoltaic cell's photoelectric conversion efficiency and stability. With the development of electronic equipment in the direction of smaller, thinner and smarter, the requirements for conductive silver paste are getting higher and higher. The future of conductive silver paste should not only have a higher conductivity and better adhesion, but also need to have better flexibility and lower cost. In addition, the research and development of environmentally friendly conductive silver paste has also become one of the industry's focus.
In short, conductive silver paste as an indispensable basic material in the electronics industry, its performance optimization and technological innovation will directly affect the progress and development of the industry as a whole. With the application of continuous updating progress, we have reason to expect that the conductive silver paste in the future will have a wider range of application prospects.
