US 2002/0172412 A1 · Wafer color variation correcting method, selective wafer defect detecting method, and computer readable recording media for the same

Abstract

A method for correcting color variations on the surface of a wafer, a method for selectively detecting a defect from different patterns, and computer readable recording media for the same are provided. Color variations in images of different parts of a wafer can be corrected using the mean and standard deviation of grey level values for the pixels forming each of the different parts of the wafer. In addition, different threshold values are applied to metal interconnect patterns and spaces of the wafer so that a defect can be selectively detected from the different patterns. Thus, a bridge known as a fatal, or killing defect to a semiconductor device can be detected without also falsely detecting grains as fatal defects. Due to increased defect screening capacity of the methods, the defect detecting method can be further efficiently managed.

Claims22

Dependent claims

A color variation correcting method comprising:

dividing images of the surface of a wafer having an X region of a first color value and a Y region of a second color value into pixels having a predetermined size;
determining a grey level value for each of the pixels;
calculating the mean and standard deviation of grey level values for the pixels in each of the X and Y regions;
and
correcting the grey level value for each of the pixels in the X region such that the mean and standard deviation of the grey level values of the X region are equal to those of the Y region.

2 more elements

A defect detecting method comprising:

dividing images of the surface of a wafer, in which a line pattern and a space between adjacent line patterns having a smaller grey level than the line pattern are alternately and repeatedly arranged, into pixels having a predetermined size;
determining a grey level value for each of the pixels;
setting a first threshold value for the line pattern and a second threshold value for the space;
and
identifying pixels that have a grey level value greater than or equal to the first threshold value for pixels of the line pattern and the second threshold value for pixels of the space.

2 more elements

A computer readable recording medium having embodied therein a computer program code unit for detecting defects in a wafer, the computer program code unit comprising:

a program module for dividing images of the surface of the wafer, in which a line pattern and a space having a smaller grey level than the line pattern are alternately and repeatedly arranged, into pixels having a predetermined size;
a program module for determining a grey level value for each of the pixels;
a program module for setting a first threshold value for the line pattern and a second threshold value for the space;
and
a program module for identifying pixels that have a grey level value greater than or equal to the first threshold value for pixels of the line pattern and the second threshold value for pixels of the space.

2 more elements

Dependencies are inferred from the claim text.

Wafer color variation correcting method, selective wafer defect detecting method, and computer readable recording media for the same

Life of this patent

Wafer color variation correcting method, selective wafer defect detecting method, and computer readable recording media for the same

Life of this patent

Abstract

Claims22