Silver plastic

The classification of conductive silver paste are many kinds of conductive silver paste, according to the direction into isotropic conductive silver conductive glue (ICAs, Isotropic Conductive Adhesive) and anisotropic conductive silver paste (ACAs, Anisotropic Conductive Adhesives). ICA is all in all directions conductive adhesive, can be used in a variety of electronics; ACA refers to a direction in the Z direction, such as electrical conductivity, and in the X and Y direction is not conductive adhesive. In general ACA preparation of equipment and technology higher, less easy to achieve, more fine print for the board and so on, such as flat panel displays (FPDs) in the printing plate. in accordance with the conductive silver glue curing system can be divided into conductive silver paste cured at room temperature, the temperature curing conductive silver plastic, high temperature curing conductive silver adhesive, UV curable conductive silver glue. room temperature curing conductive silver paste more unstable when stored at room temperature volume resistivity is easy to change. heat curing at high temperature conductive silver glue easily oxidized metal particles, curing time requirements must be short to meet the requirements of conductive silver paste. at home and abroad is the application of more temperature curing conductive silver paste (less than 150 ℃), the curing temperature is moderate, with the temperature of electronic components to match the capacity and temperature , mechanical properties are more excellent, so the widely used. UV curable adhesive to UV curable conductive silver and silver conductive adhesive technology combine to give the performance of conductive silver paste new and expanded scope of application of conductive silver paste can be used electroluminescence and other liquid crystal display electronic display technology, foreign from the start of the nineties of last century, China began to study in recent years. 2.2 The composition of conductive silver paste mainly composed of conductive silver adhesive resin matrix, conductive particles and dispersing additive, additives, etc. composition. currently on the market used mostly conductive silver paste filler type. filler conductive silver paste of the resin matrix, in principle, can use various types of plastic Bo agent resin matrix, generally a thermosetting adhesive commonly used as a ring epoxy resin, silicone resin, polyimide resin, phenolic resin, polyurethane, acrylic resin adhesive system. The post-curing adhesive to form a conductive silver paste of the molecular backbone structure, provided the mechanical properties and viscosity access performance guarantees, and to form a channel conductive filler particles. As epoxy resin can be cured at room temperature or below 150 ℃, and the formula can be designed with rich properties, conductive silver epoxy adhesive is currently dominant. Conductive Silver Paste conductive particles required to have good conductive properties themselves to the appropriate particle size range, can be added to the conductive silver paste to form the matrix of conductive pathways. conductive fillers can be gold, silver, copper, aluminum, zinc, iron, nickel powder and graphite and some conductive compounds 3. The current status and prospects of domestic and foreign research, the domestic production of conductive silver paste in the unit are metal research institutes, foreign enterprises have TeamChem Company, Japan's Hitachi Ltd., Three-Bond Corporation, the U.S. Epoxy company, Ablistick company, Loctite Corporation, 3M Company. commercialized conductive silver adhesive main conductive silver paste, conductive silver paste, conductive paint, conductive tape, conductive silver paste, etc., components with a single, two-component. conductive silver paste are generally used for microelectronic packaging, printed circuit board, conductive circuit bonding and other electronic fields. Today the domestic silver conductive adhesive performance in terms of variety and has a big gap with foreign countries. 4. Silver conductive adhesive applications (1) silver conductive adhesives for microelectronic assembly, including thin wires and printed circuit, electroplating floor, ceramic surface of the material of the metal layer, metal chassis connection, bonding wire and tube sockets, adhesive components through the printed circuit board with the flat face, bonding waveguide tuning and repair holes. (2) conductive silver adhesive to replace welding temperature than when the oxide film formed by welding spot welding tolerance. adhesives for tin-lead of the conductive silver replacement crystal, and its main application areas such as: telephone and mobile communication systems; radio, television, computer and other industries; automobile industry; medical equipment; address electromagnetic compatibility (EMC) and so on. (3) Another application of silver conductive adhesive is ferroelectric device electrodes and magnets for crystal bonding. Conductive adhesive could replace solder silver and crystal medicine tends to deposit due to welding temperature welding. for the battery terminal when the welding temperature bonding is unfavorable conductive silver another purpose adhesive. (4) silver conductive adhesive joints of sufficient strength can be formed, therefore, can be used as structural adhesives. 5. Domestic application of conductive silver paste some of the domestic market in areas of high use of sophisticated silver conductive adhesive based mainly on imported: Taiwan's TeamChem Company, Ablistick company, 3M Company occupied almost all of the IC and the LED field, Japan Sumitomo and Taiwan Yi Hua is also involved in these areas. Japan's Three-Bond companies control of the quartz crystal resonator side conductive silver adhesive applications. domestic conductive silver paste mainly used in some, the low-end products, this The market is mainly occupied by the Institute of Metal Research. conductive adhesive IED production package is an indispensable glue, conductive silver paste of its requirements are electric and thermal conductivity properties to numbers, to a large shear strength and stronger adhesion . Among the most famous TeamChem Company A6/HA6 series. 6. Production process 1. Process: a) Cleaning: ultrasonic cleaning PCB or LED support, and drying. b) mountings: The LED die (wafer) on the bottom electrode silver paste prepared after the expansion, the expansion of the die after the (wafer) placed in the thorn crystal table, under a microscope with a thorn in the crystal pen die mounted on a PCB or the LED of a corresponding pad on the support, followed by sintering the silver adhesive curing. c) pressure welding: welding with aluminum wire or gold wire electrodes connected to the LED die on the lead for current injection. LED mounted directly on the PCB, the general use of aluminum wire welding. (TOP-LED need to make white gold wire welder) d) Packaging: By dispensing with epoxy to protect the LED die and wire up. Dispensing in the PCB board, the shape of the cured gel, there are strict requirements, which is directly related to the backlight brightness of the finished product. This process will also assume the point of phosphor (white LED) task. e) Welding: If the backlight is the use of SMD-LED, or other encapsulated LED, in the assembly process, you need to LED soldered to the PCB board. f) cutting film: punch die with all the necessary backlight diffusion film, reflective film. g) Assembly: According to the drawings, a variety of materials to backlight manually install the correct location. h) Test: Check out the backlight optical parameters and light uniformity is good. Packaging: The finished product required packaging, warehousing.