Defect inspection device, pattern chip, and defect inspection method
In a defect inspection device that irradiates a surface of a sample or a surface of a pattern chip with an illumination light shaped to extend in a first direction, and detects a scattered light generated from the surface of the sample or the surface of the pattern chip by the illumination light to detect a defect on the surface of the sample, the pattern chip has a dot pattern area in which multiple dots are arrayed in multiple rows and multiple columns, a minimum interval between the dots corresponding to the lines aligned in the first direction among the multiple dots arrayed in the dot pattern area in a second direction orthogonal to the first direction is smaller than a width of the illumination light, and a minimum interval between the multiple dots arrayed in the dot pattern area is larger than a resolution of the detection optical system.
1. A defect inspection device comprising:
a pattern chip comprising a plurality of dots;
a table unit for holding a sample to be inspected and upon which the pattern chip is installed;
a light source that emits an illumination light that irradiates a surface of the sample or a surface of the pattern chip with an illumination light shaped to extend in a first direction;
a detection optical system that detects a diffracted light and a scattered light generated from the surface of the sample or the surface of the pattern chip by the illumination light, the detection optical system comprising an objective lens and an image sensor; and
a signal processor configured to adjust a focus of the detection optical system and to detect a defect on the surface of the sample based on a signal output from the detection optical system,
wherein the pattern chip has a dot pattern area in which the plurality of dots are arrayed in a plurality of rows and a plurality of columns, a minimum interval between the dots corresponding to the lines aligned in the first direction among the plurality of dots arrayed in the dot pattern area in a second direction orthogonal to the first direction is smaller than a width of the illumination light, and a minimum interval between the plurality of dots arrayed in the dot pattern area is larger than a resolution of the detection optical system,
wherein said plurality of dots of said dot pattern area are further arranged as a repeating plurality of smaller dot pattern areas each having a different area on said surface of said pattern chip, and
wherein said repeating plurality of smaller dot pattern areas repeat in said first direction.
2. The defect inspection device according to claim 1 , wherein a shape of the dots is round.
3. The defect inspection device according to claim 1 , wherein a diameter of the dots is smaller than a resolution of the detection optical system.
4. The defect inspection device according to claim 1 , wherein a minimum interval between the plurality of dots appearing on the same row among the dots configuring the dot pattern area is larger than a width of the illumination light.
5. The defect inspection device according to claim 1 , wherein the dots have a concave pattern.
6. The defect inspection device according to claim 1 , wherein the pattern chip further includes a one-row dot pattern configured by a pattern in which the dots are aligned in one row, and the dot pattern area and the one-row dot pattern are arranged in different areas in the first direction.
7. A pattern chip that is placed on a table unit of a defect inspection device and irradiated with an illumination light shaped to extend in a first direction, the pattern chip comprising:
a dot pattern area in which a plurality of dots are arrayed in a plurality of rows and a plurality of columns,
wherein a minimum interval between the dots corresponding to the lines aligned in the first direction among the plurality of dots arrayed in the dot pattern area in a second direction orthogonal to the first direction is smaller than a width of the illumination light,
wherein a minimum interval between the plurality of dots arrayed in the dot pattern area is larger than a resolution of a detection optical system,
wherein said plurality of dots of said dot pattern area are further arranged as a repeating plurality of smaller dot pattern areas each having a different area on a surface of said pattern chip, and
wherein said repeating plurality of smaller dot pattern areas repeat in said first direction.
8. The pattern chip according to claim 7 , wherein a shape of the dots is round.
9. The pattern chip according to claim 7 , wherein a diameter of the dots is smaller than a resolution of the detection optical system.
10. The pattern chip according to claim 7 , wherein a minimum interval between the plurality of dots appearing on the same row among the dots configuring the dot pattern area is larger than a width of the illumination light.
11. The pattern chip according to claim 7 , wherein the dots have a concave pattern.
12. The pattern chip according to claim 7 , wherein only one dot is present at the same position with respect to the second direction within a minimum repetition unit area defined by a first length in the first direction and a second length in the second direction being longer than the first length.
13. A method of inspecting a defect comprising:
a step of irradiating a surface of a pattern chip with an illumination light shaped to extend in a first direction;
a step of detecting a diffracted light and a scattered light generated from the surface of a sample or the surface of the pattern chip by irradiation of the illumination light using a detection optical system having an objective lens and an image sensor;
a step of adjusting a focus of the detection optical system based on detection signals corresponding to the refracted light and the scattered light generated from the surface of the pattern chip; and
a step of detecting a defect on the surface of the sample based on detection signals corresponding to the refracted light and the scattered light generated from the surface of the sample,
wherein the pattern chip has a dot pattern area in which a plurality of dots are arrayed in a plurality of rows and a plurality of columns, a minimum interval between the dots corresponding to the lines aligned in the first direction among the plurality of dots arrayed in the dot pattern area in a second direction orthogonal to the first direction is smaller than a width of the illumination light, and a minimum interval between the plurality of dots arrayed in the dot pattern area is larger than a resolution of the detection optical system,
wherein said plurality of dots of said dot pattern area are further arranged as a repeating plurality of smaller dot pattern areas each having a different area on said surface of said pattern chip, and
wherein said repeating plurality of smaller dot pattern areas repeat in said first direction.
14. The method of inspecting a defect according to claim 13 , wherein a shape of the dots is round.
15. The method of inspecting a defect according to claim 13 , wherein a diameter of the dots is smaller than a resolution of the detection optical system.
16. The method of inspecting a defect according to claim 13 , wherein a minimum interval between the plurality of dots appearing on the same row among the dots configuring the dot pattern area is larger than a width of the illumination light.
17. The defect inspection device according to claim 1 , wherein only one dot is present at the same position with respect to the second direction within a minimum repetition unit area defined by a first length in the first direction and a second length in the second direction being longer than the first length.
18. The method of inspecting a defect according to claim 13 , wherein only one dot is present at the same position with respect to the second direction within a minimum repetition unit area defined by a first length in the first direction and a second length in the second direction being longer than the first length.