According to the conductive temperature of silver paste sintered on the substrate, it can be divided into high-temperature silver paste and low-temperature silver paste. The high-temperature silver paste is sintered at 500 ℃ to mix silver powder, glass oxide and other solvents, which is suitable for PERC and TOPCON batteries; Low temperature silver paste sintering temperature is below 250 ℃, suitable for HJT battery.
In terms of semiconductor business, the company mainly focuses on the field of power devices and package testing, including rectifier chip, power diode, rectifier bridge and IC package testing, covering the link from chip front-end development to back-end packaging. The products are mainly diodes, integrated circuits and discrete devices, and MOSFET and IGBT packaging are considered on the basis of DFN, QFN and SMD packaging.
It is made of adhesive and diluent. According to the existing form of silver, it can be divided into oxidized silver paste, carbonate silver paste and molecular silver paste. According to the silver burning temperature, it can be divided into high-temperature silver paste and low-temperature silver paste. According to the coating method, it can be divided into printing silver paste. Spray silver paste with hanging color. A viscous slurry consisting of adhesives, solvents and additives Silver particles Metallic silver particles are the main components of conductive silver paste, and the conductive characteristics of membrane switches are mainly reflected by them. The content of silver in the slurry is directly related to the conductivity. In a sense, the high content of silver is beneficial to improving its conductivity. The formula is | m2/m1 * 23-2.19 |. Paste for making silver electrode. It consists of silver or its compounds, but its conductivity cannot be improved when its content exceeds the critical volume concentration. Generally, when the silver content is 80~90% (weight ratio), the conductivity has reached a high value. When the content continues to increase, the electrical property will no longer improve.
It can be roughly divided into:
(1) Sterling silver paste. The binder is 3%~10% lead and bismuth borosilicate glass, which is adjusted into slurry by organic carrier. The sintering temperature is 500C at low temperature and 850C at high temperature. According to different uses, the silver content can be as low as 50% and as high as 85%. For slurry with high silver content, the square resistance is less than 2m Ω/mouth.
(2) Silver palladium slurry based on silver. The content of palladium is low 2%~5%, high 18%~30%, and the sintering temperature is 850C, forming a dense silver palladium solid solution alloy. The square resistance of silver palladium slurry with high palladium content varies from 20 to 70m Ω/mouth.
(3) Silver platinum paste. The platinum content is less than 5%, the sintering temperature is 850 ℃, and the square resistance is ≤ 4m Ω/port.
(4) Polymer silver paste. The mixture of flake silver powder, resin and solvent is dried and cured at low temperature.
The silver paste is used as the electrode of mica and barium titanate ceramic capacitors, and the upper electrode of thick film capacitors. Ohmic contact silver paste is used as the grid of silicon solar cell and the electrode of positive temperature coefficient ceramic thermistor. Another type of silver paste, as the terminal electrode of chip components resistor, capacitor and inductor, can withstand electrochemical treatment such as nickel plating, lead tin alloy plating, etc. The silver palladium paste is mainly used in thick film circuits. The silver palladium paste containing 20%~25% palladium is usually welded with SnPbAg36-2 solder, which can resist the erosion of molten solder and has obvious resistance to silver migration in the high humidity DC electric field. Silver platinum paste is used instead of gold paste in microwave integrated circuits. Its conductivity and solderability are better than silver palladium paste; After replacing palladium with a small amount of platinum, it has the same corrosion resistance to molten solder. Polymer silver paste can be screen printed and dip coated. Class applies to:
The printed conductive silver paste is a low-temperature baking conductive silver paste specially designed for the circuit wires of resistive and capacitive touch screens. It is made of resin and conductive silver powder, and is suitable for use on ITO film glass. It has excellent printability, conductivity, hardness, adhesion, oxidation resistance and other characteristics.
Usage: mixing/dilution
When using, please use a plastic oil stirring knife to stir gently. If you use a metal knife, the plastic can may be cut, forming particles in the silver oil, and the screen plate will be cut when screen printing. Conductive silver paste is a ready to use product, but if you want to dilute it, please use Betterley XSJ-211 diluent, but add no more than 3% (by weight) to screen with the standard screen printing method. The dry thickness of the ink film directly affects its conductive performance, while the thickness of the ink film is related to the density of the mesh, the texture of the screen scraper, the thickness of the drying paste, etc.
Recommended film thickness: 6 to 10 μ m (i.e. 0.006mm to 0.010mm)
Screen type: 300~420 mesh polyester screen or stainless steel screen printing
(300 mesh polyester mesh is used in the test, the tension is 20-22N, the mesh weaving angle is 22.5 degrees, and the screen latex thickness is 6um)
Rubber scraper: PU rubber scraper or other solvent resistant rubber scraper. When polyester wire mesh is used, the hardness of rubber scraper is 60 to 70 degrees. If stainless steel is used,
The screen can be hard, such as 70 to 80 degrees.
Curing conditions: After conductive silver paste printing, the bottom limit PET sheet shall be baked at 130 ℃ for 40 minutes, and the glass sheet shall be baked at 150 ℃ for 50 minutes. If the temperature is higher and the time is longer, the cured silver wire will have better performance. This product can also be cured in an infrared oven. If the curing is insufficient, the conductivity and adhesion will be weakened.
Cleaning: Please use MEK, MIBK ketone solvents when cleaning.
