Inspecting apparatus and inspecting method
View Patent ↗Provided is a method wherein a multi-anode detector is used for the purpose of detecting scattered light from a wafer, data obtained from the detector (multi-anode) for detecting defects is used, the shape of a beam radiated to the wafer, a rotational shift between the radius direction and the beam long side, and the like are calculated, and the optical axis of the irradiation beam is adjusted. Furthermore, the method is provided with a technique which feeds back the correction quantities for rotation and amplitude to inspection signal data, on the basis of the correction data, and corrects inspection data. Since fine correction with the adjustment of an optics system and signal processing is made possible, positional accuracy of defect inspection and accuracy of defect level (defect size) are improved.
1. An inspecting apparatus which inspects a substrate, comprising:
a transfer system which moves a substrate;
an irradiation optics system which irradiates the substrate with first light of an elliptical shape, a length of the first light in a long side direction on the substrate being longer than a scanning pitch of the transfer system;
a multi-anode detection system which detects second light from the substrate, a length of detection elements of the multi-anode detection system being longer than a length of the second light in a long side direction on a detection surface of the multi-anode detection system; and
an adjustment unit which adjusts an optical axis of the first light using a detection result of the multi-anode detection system.
2. The inspecting apparatus according to claim 1 , wherein an intensity distribution of the first light is a Gaussian distribution, or a distribution which is constant in a radial direction and a θ direction.
3. The inspecting apparatus according to claim 1 , wherein the multi-anode detection system comprises an array of a plurality of elements in a long side direction of the second light.
4. The inspection apparatus according to claim 1 , wherein the correction unit obtains inclination angle information of the second light with respect to a radial direction of the substrate based on an intensity distribution of the second light acquired from a detection result of the multi-anode detection system, and adjust an optical axis of the first light so that a long axis direction of the first light coincides with a radial direction of the substrate using the inclination angle information of the second light.
5. An inspecting apparatus which inspects a defect on a substrate, comprising:
a transfer system which moves a substrate;
an irradiation optics system which irradiates the substrate with first light of an elliptical shape, a length of the first light in a long side direction on the substrate being longer than a scanning pitch of the transfer system;
a multi-anode detection system which detects second light from the substrate, a length of detection elements of the multi-anode detection system being longer than a length of the second light in a long side direction on a detection surface of the multi-anode detection system; and
a correction unit which obtains a center position and an intensity distribution of the second light using a detection result from the multi-anode detection system, and corrects a detection result of the defect based on the center position and the intensity distribution of the second light.
6. The inspecting apparatus according to claim 5 , wherein the correction unit conducts rotation correction or amplitude correction of the first light.
7. The inspecting apparatus according to claim 5 , wherein an intensity distribution of the first light is a Gaussian distribution, or a distribution which is constant in a radial direction and a θ direction.
8. The inspection apparatus according to claim 5 , wherein the multi-anode detection system comprises an array of a plurality of elements in a long side direction of the second light.