Patent ID: 6564648
Filing Date: 2003-05-20
Classification: G01N,H01L

Abstract:
A method for inspecting a solder ball on a BGA package, comprising the steps of:(1) providing a rotatable disk having at least one flap on a perimeter thereof, the rotatable disk being capable of being rotated if a tangential force applied to the flap is greater than a predefined threshold torque set to be equal to or less than a shear-resistant strength of a properly-bonded solder ball but greater than the shear-resistant strength of a defectively-bonded one; (2) providing a conveyance path for conveying the BGA package; and (3) positioning the rotatable disk above the conveyance path, with the flap thereon being suspended above the conveyance path to allow the solder ball on the BGA package to push tangentially against the flap; wherein the solder ball would be capable of pushing open the flap if it is a properly-bonded one and would be rejected and broken apart from the BGA package by the flap if it is a defectively-bonded one.