FRANKLIN, MA – Speedline Technologies has been granted a patent for an analysis technique used to quantify the amount and geometry of solder paste between printed deposits.

US Patent 6,891,967 describes a technique that uses the texture of solder paste to identify its position relative to the pad and soldermask.
The technology, which Speedline markets under the name MPM BridgeVision inspection, is used in screen and stencil printers.

The method is said to be more accurate for analyzing bridges than conventional methods, which typically use gray-scale based segmentation as a 2D technique, showing the difference between the gray solder paste and the dark soldermask.

In a statement today, inventor Dave Prince said, “This innovation provides a very precise method to both identify and quantify any paste that has found its way to the area between the freshly printed pasted deposits. By building off our previous patented methods for using texture as the basis for segmentation, we have found a way to derive data for SPC tracking which can then allow for intervention either by the operator or automatically when a bridging potential exceeds the control limits.”

The technique permits users to review devices that have the highest tendency to bridge and use that information for process improvement.