CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2018-0064484, filed on Jun. 4, 2018, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

The inventive concept relates to an inspection apparatus and an inspection method, and more particularly, to an inspection apparatus and an inspection method for accurately checking the presence or absence of defects on an object to be inspected.

An electron microscope, ellipsometry, or the like has been used to check the presence or absence of defects on an object to be inspected, for example, a wafer. Among them, the electron microscope is an apparatus which makes an enlarged image of an object by using an electron beam and an electron lens. The electron microscope may overcome the resolution limit of conventional optical microscopes and may perform microscopic observation, and thus is widely used for wafer inspection. Ellipsometry may calculate information about a sample by analyzing a polarization change of reflected light reflected from the sample (e.g., a wafer surface). For example, when light is reflected from a sample, the polarization state of reflected light changes depending on optical properties of a sample material and the thickness of a sample layer. Ellipsometry may derive physical information about the sample by measuring such polarization changes.

SUMMARY

The inventive concept provides a low-cost digital holography microscope (DHM) that is capable of performing inspection at high speed while accurately inspecting an object at high resolution, an inspection method using the DHM, and a method of manufacturing a semiconductor device by using the DHM.

According to an aspect of the inventive concept, there is provided a digital holography microscope (DHM) including: a light source configured to generate and output light; a beam splitter configured to cause the light to be incident on an inspection object and output reflected light from the inspection object; and a detector configured to detect the reflected light, wherein the detector generates a hologram when the reflected light includes interference light, and wherein the DHM has a lens-free path from the light source to the detector.

According to another aspect of the inventive concept, there is provided a digital holography microscope (DHM) including: a light source configured to generate and output light; a detector configured to detect reflected light produced when the light is vertically incident on an upper surface of an inspection object or incident at a set inclination angle; and an analysis and determination unit configured to analyze the reflected light to determine whether a defect is present in the inspection object, wherein the detector generates a hologram when the reflected light includes interference light and the analysis and determination unit analyzes the hologram, and wherein the DHM has a lens-free path from the light source to the detector.

According to another aspect of the inventive concept, there is provided an inspection method using a digital holography microscope (DHM) comprising a light source and a detector, the inspection method including: generating light and making the light incident on an inspection object; detecting reflected light from the inspection object; analyzing the reflected light to determine whether a defect is present in the inspection object; and generating a hologram and analyzing the hologram when the reflected light includes interference light, wherein the DHM has a lens-free path from the light source to the detector.

According to another aspect of the inventive concept, there is provided a method of manufacturing a semiconductor device by using a digital holography microscope (DHM) comprising a light source and a detector, the method including: generating light and making the light incident on an inspection object; detecting reflected light from the inspection object; analyzing the reflected light to determine whether a defect is present in the inspection object; generating a hologram and analyzing the hologram when the reflected light includes interference light; and performing a semiconductor process on the inspection object when no defect is present in the inspection object, wherein the DHM has a lens-free path from the light source to the detector.

