LGA devices have the characteristics of high assembly density,small size of electronic products and high reliability,but the bottom welding end and the bottom surface of the shell are in the same horizontal plane,and there are tin bead defects at the bottom of the device after welding in the production process.Tin bead is a typical defect in surface assembly production,which can affect the appearance of board level products,lead to abnormal circuit function,and cause devices or printed boards to be scrapped.Through the optimization of steel mesh thickness,steel mesh opening mode,patch pressure and reflow welding temperature,which will produce tin bead factors in the production process,the tin bead problem can be solved,the welding qualification rate of LGA devices can be improved,the chip scrap rate can be reduced and the product quality can be improved.
万方数据
维普
