1. StencilIn the specific SMT patch processing, the thickness of the steel mesh is generally, but in the welding process of the BGA device, the thick steel mesh is likely to cause even tin. According to Patel ’s high-precision surface assembly production experience, the thickness of The mesh is very suitable for BGA devices, in addition, it can also moderately expand the total area of the steel mesh opening.
2. Solder pasteThe pin spacing of BGA devices is relatively small, so the solder paste used also stipulates that the metal material particles should be small. Excessive metal material particles will cause continuous tin in SMT processing.
3. Welding temperature settingThe reflow soldering furnace is generally used in the entire process of SMT placement. Before welding for BGA packaged components, the temperature of each region must be set according to the processing regulations and the temperature around the spot welding must be detected using a thermal resistance camera.
4. Inspection after weldingAfter SMT processing, we must carry out rigorous testing of BGA packaged devices to prevent some chip-type defects.
5. Advantages of BGA packaging:1. Increased assembly yield;
2. The electric heating performance is improved;
3. The volume and mass are reduced;
4. The parasitic parameters are reduced;
5. The signal transmission delay is small;
6. Increased frequency of use;
7. Good product credibility;
6. Defects of BGA packaging:1. Inspection after welding must be based on X-ray;
2. Increased production cost of electronics;
3. Increased cost of repairs;Because of its packaging characteristics, the difficulty of BGA in SMT patch welding is very large, and casting defects and rework are also difficult to practically operate in order to ensure the welding quality of BGA devices. Pay attention to the customization of processing regulations.