Inspection system and method for leads of semiconductor devices

摘要

A system for transporting and inspecting, seriatim, semiconductor devices with plural prong type or solder ball type leads includes a head for transporting the semiconductor devices from one support structure, such as a tray or tube, to a second support structure, such as a tray or tape, and wherein two dimensional and three dimensional measurements of the positional accuracy of the leads is carried out during the transport process. The inspection apparatus is interposed in the transport path and includes a first optical sensor such as a CCD camera oriented to capture a two dimensional image of the semiconductor device package and compare the image with a predetermined two dimensional image store in a central processing unit (CPU). A high intensity light source, such as a laser, generates a plane of light which is reflected off of the semiconductor device leads to a second optical sensor, also comprising a CCD camera, wherein a so-called three dimensional image is generated to be compared by the CPU with predetermined or calculated positional relationships of the leads to establish coplanarity of the lead tips, or lack thereof. The system includes a sensor located such that the semiconductor device is centered in a field of view of the cameras to capture the respective images. The transport head may be rotated to correct for improper positioning of the device prior to generation of the three dimensional image. The system may interchangeably inspect semiconductor device packages with prong leads extending from one or all sides of a rectangular substrate as well an array of solder ball leads supported on a substrate. A modified arrangement of the inspection system is adapted for inspecting multiple semiconductor devices with solder ball leads and supported on wafer type substrates.