Patent ID: 6316953
Filing Date: 2001-11-13
Classification: G01R

Abstract:
A method for prober automatic alignment for aligning a prober having at least two prober alignment patterns and a wafer having at least two wafer alignment patterns, comprising the steps of:defining a first coordinate system having a center O.sub.11, and orthogonal X.sub.11 and Y.sub.1 axes on a first wafer alignment pattern having a first circular region centered at O.sub.11 ;defining a second coordinate system having a center O.sub.12, and an X.sub.12 axis orthogonal to said Y.sub.1 axis on a second wafer alignment pattern having a second circular region centered at O.sub.12 ;defining a third coordinate system having a center O.sub.21, and orthogonal X.sub.21 and Y.sub.2 axes on a first prober alignment pattern having a first virtual circle centered at O.sub.22 ;defining a fourth coordinate system having a center O.sub.22, and an X.sub.22 axis orthogonal to said Y.sub.2 axis on a second prober alignment pattern having a second virtual circle centered at O.sub.22 ;performing a pre-alignment of said first and second prober alignment patterns to said first and second wafer alignment patterns for positioning said center O.sub.21 within said first circular region and said center O.sub.22 within said second circular region, said first virtual circle having a first arc portion being positioned outside said first circular region and the mid-point of said first arc portion and said center O.sub.21 forming a first arc axis, and said second virtual circle having a second arc portion being positioned outside said second circular region and the mid-point of said second arc portion and said center O.sub.22 forming a second arc axis;acquiring a first set of measurement data for determining a first distance between said centers O.sub.11 and O.sub.21, and a first angle between said first arc axis and said Y.sub.2 axis;acquiring a second set of measurement data for determining a second distance between said centers O.sub.12 and O.sub.22, and a second angle between said second arc axis and said Y.sub.2 axis;and determining the angle between said Y.sub.1 axis and said Y.sub.2 axis by said first and second distances and said first and second angles.