Defect detector, defect detecting method and method for detecting hole figure

Abstract

Provided is a device for inspecting defects, which can inspect a pattern of a top layer with a high S / N ratio. In the device, diffracted light L2 produced by a wafer 2 being a substrate which is illuminated by illumination light L1 is guided and collected by a light receiving optical system 4 composed of a lens 41 and a lens 42, and the diffracted light L2 forming an image of the wafer 2 is focused on an image pickup device 5 used as an imaging means. The image acquired by the image pickup device 5 is subjected to an image processing step carried out by an image processing device 6, thereby detecting the defect. A polarizer 7 is adjusted so that the illumination light L1 illuminates the wafer 2 in S polarization. Because the S polarization makes a surface reflectivity higher, the amount of light reaching a base portion is reduced. Accordingly, the amount of light reflected by the top layer can be made larger than that reflected by the base portion, by using the S polarization for the illumination, thereby enabling the defect of the top layer to be inspected with the high S / N ratio.

Description

technical field [0001] The present invention relates to a defect inspection device and defect inspection method for inspecting defects such as unevenness and damage on the surface of a substrate, and a method for inspecting hole patterns such as contact holes, for example, in a manufacturing process of a semiconductor element or the like. Background technique [0002] In the manufacture of semiconductor devices and liquid crystal substrates, the work of forming various circuit patterns and stacking them in several layers is repeated. The outline of the process of forming each circuit pattern is to apply a photoresist on the surface of the substrate, use an exposure device to burn out the circuit pattern on the photoresist and the index line and the mask, and form a photoresist through development. After the circuit pattern formed by the resist, each part of the element is formed by etching or the like. After forming a pattern of photoresist, the pattern is checked for abnor...

AI Technical Summary

Problems solved by technology

Therefore, when the influence of the base pattern is large, noise will be formed, and the pattern information of the uppermost layer that should be inspected will be relatively reduced, thereby deteriorating the S / N ratio.

In particular, since the hole patterns such as contact holes that connect circuit patterns of different layers are very fine, the pattern density is low, and their signal strength is weak, they are easily affected by the substrate, so that defects cannot be sufficiently inspected in the prior art.

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