Method of inspecting surface and method of manufacturing semiconductor device

Abstract

Provided are a method of inspecting a surface and a method of manufacturing a semiconductor device. The methods include preparing a substrate, selecting a spatial resolution of a first optical device by setting a magnification of an imaging optical system, emitting multi-wavelength light toward a first measurement area of the substrate and obtaining first wavelength-specific images, generating first spectrum data based on the first wavelength-specific images, generating first spectrum data of respective pixels based on the first wavelength-specific images, and extracting a spectrum of at least one first inspection area having a range of the first measurement area or less from the first spectrum data, and analyzing the spectrum. The first optical device includes a light source, an objective lens, a detector, and an imaging optical system. The obtaining first wavelength-specific images includes using the imaging optical system and the detector.

What is claimed is: 
     
         1 . A method of inspecting a surface, the method comprising:
 preparing a substrate which is an inspection target;   selecting a spatial resolution of a first optical device,
 the first optical device including a light source configured to emit light, an objective lens configured to transmit light received from the light source, a detector, and an imaging optical system configured to image light detected by the detector, 
   the selecting the spatial resolution of the first optical device including setting a magnification of the imaging optical system;   emitting multi-wavelength light toward a first measurement area of the substrate using the light source to emit the multi-wavelength light and the objective lens to transmit the multi-wavelength light received from the light source towards the first measurement area;   obtaining first wavelength-specific images using the imaging optical system and the detector;   generating first spectrum data of respective pixels based on the first wavelength-specific images;   extracting a spectrum of at least one first inspection area having a range of the first measurement area or less from the first spectrum data; and   analyzing the spectrum.   
     
     
         2 . The method of  claim 1 , wherein the obtaining the first wavelength-specific images includes correcting light intensity distributions due to various angle distributions of the multi-wavelength light, and
 the correcting the light intensity distributions includes:   emitting light including various angle distributions toward a uniform test substrate using the light source and generating a correction table based on a light intensity distribution of light reflected by the test substrate;   emitting light including various angle distributions using the light source toward the first measurement area and obtaining a preliminary image of the first measurement area; and   obtaining a corrected image from the preliminary image using the correction table.   
     
     
         3 . The method of  claim 1 , wherein
 the obtaining of the first wavelength-specific images comprises correcting a position misalignment and size difference which occur between the first wavelength-specific images due to different wavelengths;   the first optical device includes a stage configured to support the substrate; and   the correcting the position misalignment and the size difference includes measuring the position misalignment and size difference between the first wavelength-specific images, moving the stage for each wavelength so as to compensate for the position misalignment and the size difference, and re-obtaining wavelength-specific corrected images after the stage is moved for each wavelength.   
     
     
         4 . The method of  claim 1 , further comprising:
 selecting a measurement mode before the obtaining of the first wavelength-specific images, wherein   the selecting the measurement mode includes selecting any one of a first measurement mode having a first numerical aperture and a second measurement mode having a second numerical aperture smaller than the first numerical aperture based on a type of a parameter to be inspected in the first inspection area,   wherein the parameter is at least one of uniformity of a surface, a thickness and width of a structure, an etched depth, a critical dimension, and a shape.   
     
     
         5 . The method of  claim 1 , further comprising:
 selecting a measurement mode before the obtaining of the first wavelength-specific images, wherein   the selecting the measurement mode includes selecting any one of a first measurement mode having a first numerical aperture and a second measurement mode having a second numerical aperture smaller than the first numerical aperture based on a type of a parameter to be inspected in the first inspection area,   wherein the selecting the measurement mode includes selecting the first measurement mode if the parameter is one of uniformity of a surface, a thickness of a single structure, a width of a single structure, an etch depth of a single hole, a critical dimension of a single structure, and a shape of a single structure, and the selecting the measurement mode includes selecting the second measurement mode if the parameter is an arrangement of a plurality of structures.   
     
     
         6 . The method of  claim 1 , further comprising:
 selecting a measurement mode before the obtaining of the first wavelength-specific images, wherein   the selecting the measurement mode includes selecting any one of a first measurement mode having a first numerical aperture and a second measurement mode having a second numerical aperture smaller than the first numerical aperture based on a type of a parameter to be inspected in the first inspection area,   wherein:   the first optical device further includes an aperture arranged on a light path on which light generated from the light source is transmitted toward the substrate, and   the selecting the measurement mode is performed by changing the objective lens or changing a shape of the aperture.   
     
     
         7 . The method of  claim 1 , wherein the first inspection area is at least one pixel of the first wavelength-specific images. 
     
     
         8 . The method of  claim 1 , further comprising:
 previously analyzing the substrate before the selecting of the spatial resolution of the first optical device, wherein   the previously analyzing of the substrate includes,
 emitting multi-wavelength light toward a second measurement area of the substrate using a second optical device and obtaining second wavelength-specific images, 
 generating second spectrum data of respective pixels based on the second wavelength-specific images, 
 extracting a spectrum of at least one second inspection area from the second spectrum data and previously analyzing the spectrum of the at least one second inspection area, and 
 determining whether there is a region of interest, which requires detailed inspection, in the second inspection area in the previously analyzing of the substrate, and 
   the region of interest is the first measurement area, wherein   the second inspection area and the region of interest are smaller than the second measurement area, and   the first inspection area is smaller than the region of interest.   
     
     
         9 . The method of  claim 1 , further comprising:
 previously analyzing the substrate before the selecting of the spatial resolution of the first optical device, wherein   the previously analyzing of the substrate includes,
 emitting multi-wavelength light toward a second measurement area of the substrate using a second optical device and obtaining second wavelength-specific images, 
 generating second spectrum data of respective pixels based on the second wavelength-specific images, 
 extracting a spectrum of at least one second inspection area from the second spectrum data and previously analyzing the spectrum of the at least one second inspection area, and 
 determining whether there is a region of interest, which requires detailed inspection, in the second inspection area in the previously analyzing of the substrate, and 
   the region of interest is the first measurement area, wherein the spatial resolution of the first optical device is higher than a spatial resolution of the second optical device.   
     
     
         10 . A method of manufacturing a semiconductor device, the method comprising:
 performing a prior manufacturing process on a substrate; and   primarily inspecting the substrate using an optical device,
 the optical device including a light source configured to emit light, an objective lens configured to transmit light received from the light source, a detector, and an imaging optical system configured to image light detected by the detector, 
 the primarily inspecting the substrate includes selecting a spatial resolution of the optical device by changing a magnification of the imaging optical system, emitting multi-wavelength light toward a measurement area of the substrate using the light source and the objective lens, and obtaining wavelength-specific images, 
   generating spectrum data of respective pixels based on the wavelength-specific images, and extracting a spectrum of at least one inspection area having a range of the measurement area or less from the spectrum data, and analyzing the spectrum of the at least one inspection area,   performing a subsequent manufacturing process on the substrate after the primarily inspecting of the substrate;   determining whether it is necessary to perform inspection on the substrate on which the subsequent manufacturing process is performed; and   secondarily inspecting the substrate on which the subsequent manufacturing process is performed in the same method as the primary inspection when it is determined that the inspection is necessary.   performing a subsequent manufacturing process on the substrate after the primarily inspecting of the substrate;   determining whether it is necessary to perform inspection on the substrate on which the subsequent manufacturing process is performed;   secondarily inspecting the substrate on which the subsequent manufacturing process is performed in response to determining that the inspection is necessary, the secondarily inspecting the substrate being performed using the same method as the primarily inspecting the substrate; and   after the secondary inspection, measuring a structural change of the inspection area by the subsequent manufacturing process by comparing the obtained wavelength-specific images of the substrate on which the prior manufacturing process is performed to obtained wavelength-specific images of the substrate on which the subsequent manufacturing process is performed, wherein   an inspection area in the secondary inspection is the same as the inspection area in the primary inspection.   
     
     
         11 . A method of manufacturing a semiconductor device, the method comprising:
 preparing a substrate including an alignment mark;   selecting a spatial resolution of an optical device,
 the optical device including a light source configured to emit light, an objective lens configured to transmit light received from the light source, a detector, and an imaging optical system configured to image light detected by the detector, 
 the selecting the spatial resolution of the optical device includes setting a magnification of the imaging optical system; 
   emitting light toward an area in which the alignment mark is formed using the light source and the objective lens;   obtaining images using the optical device; and   aligning the substrate based on the images,
 the aligning of the substrate includes checking a position of the alignment mark of the substrate based on the images, and 
   moving the substrate so that the alignment mark is aligned with preset coordinates.   
     
     
         12 . The method of  claim 11 , wherein
 the light is multi-wavelength light,   the images are wavelength-specific images, and   the aligning of the substrate is performed based on the images with respect to at least one wavelength of the wavelength-specific images.   
     
     
         13 . The method of  claim 11 , further comprising, before the obtaining of the images, selecting the spatial resolution,
 wherein the selecting of the spatial resolution comprises selecting the spatial resolution by changing the magnification of the imaging optical system, and   the optical device comprises the objective lens configured to emit the light received from the light source toward the substrate and the imaging optical system configured to image the light reflected by the substrate to the detector.   
     
     
         14 . A method of manufacturing a semiconductor device, the method comprising:
 primarily inspecting the substrate according to the method of  claim 11 ; and   performing a subsequent manufacturing process on the substrate after the primarily inspecting the substrate.