Broad band referencing reflectometer

Abstract

A spectroscopy system is provided which is optimized for operation in the VUV region and capable of performing well in the DUV-NIR region. Additionally, the system incorporates an optical module which presents selectable sources and detectors optimized for use in the VUV and DUV-NIR. As well, the optical module provides common delivery and collection optics to enable measurements in both spectral regions to be collected using similar spot properties. The module also provides a means of quickly referencing measured data so as to ensure that highly repeatable results are achieved. The module further provides a controlled environment between the VUV source, sample chamber and VUV detector which acts to limit in a repeatable manner the absorption of VUV photons. The use of broad band data sets which encompass VUV wavelengths, in addition to the DUV-NIR wavelengths enables a greater variety of materials to be meaningfully characterized. Array based detection instrumentation may be exploited to permit the simultaneous collection of larger wavelength regions.

1 . (canceled) 
     
     
         2 . A method for analyzing a scattering or diffracting structure, comprising:
 providing a below deep ultra-violet (DUV) wavelength reflectometer configured for normal incidence operation and having a light source that provides at least below DUV wavelength light;   obtaining reflectance data from the scattering or diffracting structure, including reflectance data for wavelengths below DUV wavelengths; and   utilizing the reflectance data to obtain dimension information of the scattering or diffracting structure.   
     
     
         3 . The method of  claim 2 , further comprising utilizing referencing to account for system and environmental changes to adjust reflectance data obtained through use of the reflectometer. 
     
     
         4 . The method of  claim 2 , wherein the reflectometer utilizes a non-polarizing optical path such that a polarization independent measurement may be obtained. 
     
     
         5 . The method of  claim 2 , wherein the below DUV wavelength light is non-polarized at a point in an optical path of the reflectometer at which the scattering or diffracting structure is located. 
     
     
         6 . The method of  claim 2 , wherein the dimension information comprises at least one of line width, sidewall angle, line height, trench depth, trench width and film thickness. 
     
     
         7 . The method of  claim 2 , wherein scatterometry techniques are utilize to determine the dimension information. 
     
     
         8 . The method of  claim 7 , wherein rigorous coupled wave analysis techniques are utilized to determine the dimension information. 
     
     
         9 . A method for analyzing a scattering or diffracting structure, comprising:
 providing a below deep ultra-violet (DUV) wavelength referencing reflectometer configured for normal incidence operation and having a non-polarizing optical system that provides at least below deep ultra-violet wavelength light, and   utilizing scatterometry techniques for obtaining dimensional information of the scattering or diffracting structure.   
     
     
         10 . The method of  claim 9 , further comprising utilizing referencing to account for system and environmental changes to adjust reflectance data obtained through use of the reflectometer. 
     
     
         11 . The method of  claim 10 , wherein the dimension information comprises at least one of line width, sidewall angle, line height, trench depth, trench width and film thickness. 
     
     
         12 . The method of  claim 9 , wherein the dimension information comprises at least one of line width, sidewall angle, line height, trench depth, trench width and film thickness. 
     
     
         13 . The method of  claim 9 , wherein rigorous coupled wave analysis techniques are utilized to determine the dimension information. 
     
     
         14 . A scatterometry method to determine dimensional information of a patterned structure, comprising:
 providing a reflectometer that utilizes as least in part below deep ultra-violet (DUV) wavelength light;   obtaining reflectance data from the scattering or diffracting structure, including reflectance data for at least some wavelengths below DUV wavelengths; and   utilizing scatterometry techniques to analyze the reflectance data to obtain dimension information of the pattern structure.   
     
     
         15 . The method of  claim 14 , wherein the reflectometer utilizes a non-polarizing optical path such that a polarization independent measurement may be obtained. 
     
     
         16 . The method of  claim 14 , wherein the below DUV wavelength light is non-polarized at a point in an optical path of the reflectometer at which the patterned structure is located. 
     
     
         17 . The method of  claim 14 , wherein the dimension information comprises at least one of line width, sidewall angle, line height, trench depth, trench width and film thickness. 
     
     
         18 . The method of  claim 14 , wherein the scatterometry techniques include rigorous coupled wave analysis techniques.