As today's advanced processes tend to use smaller components, such as 01005, μBGA or PoP, the use of SPI solder paste inspection machines in SMT production processes is particularly important and will become a standard process for quality assurance.

Compared with other SMT processes, the solder paste printing process has more variables and potential instability. The printing process has a variability of more than 60%. The reason for such a large variability is that the printing process contains a large number of uncertain process parameters. It is generally believed that the sum of these parameter variables is close to 40, including but not limited to solder paste. Type, formulation, environmental conditions, type of stencil, stencil thickness. Aperture aspect ratio and area ratio, press type, doctor blade, print head technology, printing speed, etc.

In the SMT process, the SPI solder paste inspection machine is behind the solder paste printing, which controls the quality of the solder paste printing. The SPI solder paste inspection machine uses optical principles to scan the solder paste on the PCB board through the laser contact 3D scanning technology, uses a high-resolution digital camera to separate the laser contour, and calculates the thickness distribution of the solder paste according to the fluctuation. The purpose of monitoring solder paste printing quality.