Broad band referencing reflectometer
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.