Defect inspection apparatus and its method
View Patent ↗A defect inspection apparatus for inspecting defects on an inspecting object includes an illuminator which irradiates a beam of light on the inspecting object, a photo-detector which detects rays of light from the inspecting object due to the irradiation of the light beam by the illuminator, a defect detector which detects a defect by processing a signal obtained through detection by the photo-detector, a characteristic quantity calculator which calculates a characteristic quantity related to a size of the defect, and a defect size calculator which uses a relation between size and characteristic quantity which is calculated by an optical simulation and calculates a size of the detected defect.
1. A defect inspection apparatus for inspecting defects on an inspecting object, comprising:
an illuminator which irradiates a beam of light on the inspecting object;
a photo-detector which detects rays of light from the inspecting object due to the irradiation of the light beam by the illuminator;
a defect detector which detects a defect by processing a signal obtained through detection by the photo-detector;
a characteristic quantity calculator which calculates a characteristic quantity related to a size of the defect; and
a defect size calculator which uses a relation between size and characteristic quantity which is calculated by a simulation and calculates a size of the detected defect.
2. A defect inspection apparatus according to claim 1 , wherein the calculated characteristic quantity is a sum total of intensities of the signal.
3. A defect inspection apparatus according to claim 1 , wherein the calculated characteristic quantity is a maximum value of intensities of the signal.
4. A defect inspection apparatus according to claim 1 , wherein the photo-detector has a sampling pitch which is no greater than ½ of the optical resolution.
5. A defect inspection apparatus according to claim 1 , wherein in a process for determining the size of a defect, parameters inherent of the inspection apparatus are used.
6. A defect inspection method for detecting defects on an inspecting object, comprising the steps of:
irradiating a beam of light on the inspecting object;
photo-detecting rays of light from the inspecting object due to the irradiation of the light beam;
detecting a defect by processing a signal obtained detection of the rays of light;
calculating by a hardware processor a characteristic quantity related to a size of the defect; and
calculating by a hardware processor a defect size using a relation between size and characteristic quantity which is calculated by a simulation so as to calculate a size of the detected defect.
7. A defect inspection method according to claim 6 , wherein the calculated characteristic quantity is based upon a sum total of intensities of the signal.
8. A defect inspection method according to claim 6 , wherein the calculated characteristic quantity is based upon a maximum value of intensities of the signal.
9. A defect inspection method according to claim 6 , wherein the photo-detecting step is executed at a sampling pitch which is no greater than ½ of the optical resolution.
10. A defect inspection method according to claim 6 , wherein in a process for determining the size of a defect, parameters inherent of an inspection apparatus are used.