Method of determining the irregularities of a hole

• US 7,398,178 B2
• Filed: 09/29/2004
• Issued: 07/08/2008
• Est. Priority Date: 10/27/2003
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kang, Hyo-Cheon
• Primary Examiner(s): Barbee; Manuel L.
• Application Number:
  US10/954,254
• Publication Number:
  US 20050090999A1
• Time in Patent Office: 1,378 Days
• Field of Search: 702 81- 84, 702/150, 702/151, 702155-157, 702 33- 36, 702/127, 702/158, 702/159, 702/166, 702/167, 33/1.SP, 335/551, 33/1.BB, 331/21, 331/23, 335/42, 335/43, 700/303, 700/58, 700/111, 356/492, 356/495, 356/496, 356/511, 356/625, 356/628, 356/629
• US Class Current: 702/155
• CPC Class Codes: G01B 15/08 for measuring roughness or irregularity of surfaces

Abstract

In a method of calculating irregularities of a hole, a center coordinate of an actual hole is set. Inner wall coordinates of the actual hole are obtained from the center coordinate of the actual hole. An area of the actual hole is determined based on the inner wall coordinates of the actual hole. A radius of a virtual hole is determined based on the area of the actual hole. A center coordinate of the virtual hole is determined based on the inner wall coordinates of the actual hole to obtain a circumference line of the virtual hole. A standard deviation of the inner wall coordinates of the actual hole relative to the circumference line of the virtual hole is calculated, thereby obtaining the irregularities of the actual hole.

Claims

1. An inspection equipment-implemented method of determining irregularities of an actual hole having an irregular circumference, comprising:

scanning the actual hole having the irregular circumference formed in an object to obtain an area of the actual hole, wherein determining the area of the actual hole comprises setting a center coordinate of the actual hole, obtaining inner wall coordinates of the actual hole measured from the center coordinate of the actual hole, and determining the area of the actual hole based on the inner wall coordinates of the actual hole, and wherein determining the area of the actual hole further comprises drawing lines from the center coordinate of the actual hole to the inner wall coordinates of the actual hole to segment the actual hole into a plurality of triangles;

determining a radius and a center of a virtual hole that has a regular circumference, based on the area of the actual hole; and

obtaining the irregularities of the actual hole by determining a standard deviation of the circumference of the actual hole relative to the radius of the virtual hole to output whether the irregularities of the actual hole are within a critical irregularity.

2. The method of claim 1, wherein determining the area of the actual hole comprises:

providing lines from the center coordinate of the actual hole to the inner wall coordinates of the actual hole to segment the actual hole into a plurality of triangles;

determining the area of each of the triangles; and

summing the areas of the triangles.

3. The method of claim 2, wherein angles formed between the lines are substantially identical.

4. The method of claim 1, wherein the actual hole is located in a semiconductor device.

5. The method of claim 1, wherein the radius and the center of the virtual hole that has a regular circumference is calculated based on the area of the actual hole;

and

the irregularities of the actual hole are determined by calculating the standard deviation of the circumference of the actual hole relative to the radius of the virtual hole.

6. The method of claim 1, wherein determining the area of the actual hole comprises calculating the area of the actual hole based on the inner wall coordinates of the actual hole.

7. The method of claim 1, wherein the inspection equipment comprises a scanning electron microscope.

8. An inspection equipment-implemented method of determining irregularities of an actual hole having an irregular circumference located in a semiconductor device, comprising:

scanning the actual hole in the semiconductor device having the irregular circumference to obtain an area of the actual hole, wherein determining the area of the actual hole in the semiconductor device comprises setting a center coordinate of the actual hole in the semiconductor device, obtaining inner wall coordinates of the actual hole in the semiconductor device measured from the center coordinate of the actual hole, and determining the area of the actual hole in the semiconductor device based on the inner wall coordinates of the actual hole, and wherein determining the area of the actual hole in the semiconductor device further comprises drawing lines from the center coordinate of the actual hole in the semiconductor device to the inner wall coordinates of the actual hole in the semiconductor device to segment the actual hole into a plurality of triangles;

determining a radius and a center of a virtual hole that has a regular circumference, based on the area of the actual hole in the semiconductor device; and

obtaining the irregularities of the actual hole in the semiconductor device by determining a standard deviation of the circumference of the actual hole relative to the radius of the virtual hole to output whether the irregularities of the actual hole are within a critical irregularity.

9. The method of claim 8, wherein determining the area of the actual hole in the semiconductor device comprises:

providing lines from the center coordinate of the actual hole in the semiconductor device to the inner wall coordinates of the actual hole in the semiconductor device to segment the actual hole in the semiconductor device into a plurality of triangles;

determining the area of each of the triangles; and

summing the areas of the triangles.

10. The method of claim 9, wherein angles formed between the lines are substantially identical.

11. The method of claim 8, wherein the radius and the center of the virtual hole that has a regular circumference is calculated based on the area of the actual hole in the semiconductor device;

and

the irregularities of the actual hole in the semiconductor device are determined by calculating the standard deviation of the circumference of the actual hole in the semiconductor device relative to the radius of the virtual hole.

12. The method of claim 8, wherein determining the area of the actual hole in the semiconductor device comprises calculating the area of the actual hole in the semiconductor device based on the inner wall coordinates of the actual hole in the semiconductor device.

13. The method of claim 8, wherein the inspection equipment comprises a scanning electron microscope.

19. The method of claim 9, wherein angles formed between the lines are substantially identical.

14. An inspection equipment-implemented method of determining irregularities of a hole comprising:

scanning an actual hole formed in an object to set a center coordinate (x_c′

,y_c′

) of a actual hole;

obtaining n inner wall coordinates (x₁,y₁), (x₂,y₂), (x₃,y3), . . . , (x_i,y_i), . . . , (x_n,y_n), wherein n is a positive integer, of the actual hole from the center coordinate of the actual hole;

drawing lines from the center coordinate of the actual hole to the inner wall coordinates of the actual hole to divide the actual hole into triangles, the lines having substantially equal angles between thereof;

summing an area of each of the triangles to obtain an area of the actual hole;

determining a radius r of a virtual hole based on the area of the actual hole;

obtaining a center coordinate (x_c,y_c) of the virtual hole by summing the inner wall coordinates of the actual hole and then dividing the summed inner wall coordinates by n;

determining distances I_i between the center coordinate of the virtual hole and the inner wall coordinates of the actual hole; and

obtaining the irregularities of the actual hole, to output whether the irregularities of the actual hole are within a critical irregularity, by determining a standard deviation σ

of the distances relative to the radius of the virtual hole using following equation;

$\mathrm{\sigma <br><br>}=\frac{\sqrt{\underset{i=1}{\overset{n}{\sum <br><br>}}<br><br>{\left(l_i-r\right)}^2}}{n}.$

15. The method of claim 14, wherein the actual hole is located in a semiconductor device.

16. An inspection equipment-implemented method of determining irregularities of an actual hole having an irregular circumference, comprising:

scanning the actual hole having the irregular circumference formed in an object to obtain an area of the actual hole, wherein determining the area of the actual hole comprises setting a center coordinate of the actual hole, obtaining inner wall coordinates of the actual hole measured from the center coordinate of the actual hole, and determining the area of the actual hole based on the inner wall coordinates of the actual hole, wherein determining the area of the actual hole further comprises providing lines from the center coordinate of the actual hole to the inner wall coordinates of the actual hole to segment the actual hole into a plurality of triangles, determining the area of each of the triangles, and summing the areas of the triangles;

determining a radius and a center of a virtual hole that has a regular circumference, based on the area of the actual hole; and

obtaining the irregularities of the actual hole by determining a standard deviation of the circumference of the actual hole relative to the radius of the virtual hole to output whether the irregularities of the actual hole are within a critical irregularity.

17. The method of claim 16, wherein angles formed between the lines are substantially identical.

18. An inspection equipment-implemented method of determining irregularities of an actual hole having an irregular circumference located in a semiconductor device, comprising:

scanning the actual hole in the semiconductor device having the irregular circumference to obtain an area of the actual hole, wherein determining the area of the actual hole in the semiconductor device comprises setting a center coordinate of the actual hole in the semiconductor device, obtaining inner wall coordinates of the actual hole in the semiconductor device measured from the center coordinate of the actual hole, and determining the area of the actual hole in the semiconductor device based on the inner wall coordinates of the actual hole, and wherein determining the area of the actual hole in the semiconductor device further comprises providing lines from the center coordinate of the actual hole in the semiconductor device to the inner wall coordinates of the actual hole in the semiconductor device to segment the actual hole in the semiconductor device into a plurality of triangles, determining the area of each of the triangles, and summing the areas of the triangles;

determining a radius and a center of a virtual hole that has a regular circumference, based on the area of the actual hole in the semiconductor device; and

obtaining the irregularities of the actual hole in the semiconductor device by determining a standard deviation of the circumference of the actual hole relative to the radius of the virtual hole to output whether the irregularities of the actual hole are within a critical irregularity.