[vol.9] December 2020


Inspection of Lead Lift of IC in Tray

1.Lead Lift of IC (Integrated Circuit) Components
Among the SMT devices, IC components such as QFP (Quad Flat Package) and SOP (Small Outline Package) that are stored in the tray can experience lift and warpage of lead during the copy process due to raw material defects, components falling, and careless worker handling. Lead lift can cause a cold solder joint, which is the state in which the solder isn’t completely attached to the PCB in reflow. In this case, this can cause a fatal defect in the quality of products. PARMI Xceed (3D AOI), however, can inspect for lead lift using 2D & 3D image data so users can prevent the attachment of defective components in advance.


2.Laser Scanning Method
1) The Shadow Effect
When inspecting the components in the tray, there is a shadow cast by the component. But the dual laser projection of Xceed can perform inspection without the shadow effect due to its narrow projection angle of 14.5°.


2) 3D Height Inspection
When lead lift is identified via 2D image, the defect is distinguished by a length difference in the lead. Defective leads look longer than normal leads due to lift. However, this difference is invisible to the naked eye, so false calls can occur.

Xceed can distinguish lead lift using 3D height data. A laser scanning method enables it to acquire fast and accurate height data.