Apparatus and method for testing coplanarity of semiconductor components
AssigneeSantana Engineering Systems
InventorsRobert L. Comstock, Michael R. Hansen, Edrick H. Tong
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Abstract
A method and apparatus for measuring the alignment of leads along the perimeter of an integrated circuit surface mount device (SMD). The device is placed so that a first lead is within the path of a beam of light emitted from a light source. The light source is moved around the perimeter of the device so that the beam of light contacts all of the leads of the device. The angle of reflection of the beam of light off of each of the leads is detected. From this angle, the alignment of the leads is determined by first calculating a seating plane and then calculating the variation of each lead from the seating plane.
Claims18
A method for measuring the coplanarity of the contact points of a plurality of leads disposed along the perimeter of an integrated circuit package, comprising:
- positioning a first lead of said plurality of leads of said integrated circuit package to have its contact point disposed within the path of a beam of light emitted from a light source;
- determining the position of a seating plane;
- moving said light source relative to said package around the perimeter of said package so that said beam of light illuminates each of the contact points of said leads of said package;
- detecting a position of reflection of said beam of light off of the contact point of each of said leads;
- and
- determining whether the detected position of reflection for any of said leads is outside a predetermined tolerance of said seating plane.
An apparatus for measuring the coplanarity of the contact points of a plurality of leads disposed around the perimeter of an integrated circuit package, comprising:
- a probe having an emitter for emitting a beam of monochromoatic light onto the contact portions of the leads of an IC package, and a detector for detecting a position of reflection of said beam from said contact portions and producing an electrical signal proportional to said postion of reflection for each said lead;
- means for positioning said integraed circuit package proximate said probe;
- means for moving said probe and package relative to each other so that said beam is reflected off said contact portions of said leads;
- and
- means for analyzing said electrical signal to determine the coplanarity of said contact portions of said leads.
Dependencies are inferred from the claim text.