A photomask-inspection system includes a vacuum chamber and a stage, disposed in the vacuum chamber, to support a photomask and to translate the photomask horizontally and vertically. The system also includes an EUV objective, disposed in the vacuum chamber, to collect EUV light from the photomask to inspect the photomask for defects and an optical height sensor, at least partially disposed in the vacuum chamber, to measure heights on a surface of the photomask. The system further includes a stage controller to translate the stage horizontally and vertically in accordance with a focal map for the photomask produced using the measured heights on the surface of the photomask.

A method and apparatus are described for measuring the concentration of a gas with an absorption band in the ultraviolet range. The device includes an absorption chamber containing a gas, a light source, a selected optical bandpass filter, and ultraviolet photodetectors. The gas concentration is measured by the ratio of a transmitted intensity to an incident intensity with the Beer-Lambert Law relation. A second light source may be used for a compensation signal. A second method periodically changes the absorption coefficient by inserting a transparent material in the absorption path to measure the optical compensation signal. A third method periodically shortens the optical absorption path by moving the active detector closer to the light source to measure the optical compensation signal. The fourth method uses an optical element to deflect the optical beam to create a shorter absorption path as a reference for the incident signal using one detector.

Methods, apparatus, and processes which use Extreme ultraviolet radiation (EUV) and/or soft X-ray wavelengths to read, image, edit, locate, identify, map, alter, delete, repair and sequence genes are described. An EUV scanning tool which allows high throughput genomic scanning of DNA, RNA and protein sequences is also described. A database which records characteristic absorption spectra of gene sequences is also described.

We have invented an EUV spectroscopic polarimeter including a light receiving element, a first polarizing modulation element, a second polarizing modulation element, an energy splitting element and a light detecting and analyzing apparatus. The light receiving element is for receiving a target light. The first polarizing modulation element is rotatably connected to the light receiving element for generating a first polarized light. The second polarizing modulation element is rotatably connected to the first polarizing modulation element for generating a second polarized light. The energy splitting element receives the second polarized light so as to generate a modulated-polarization and energy-resolved light. The light detecting and analyzing apparatus receiving the polarization-modulated and energy-resolved light and providing a spectrum information by an analyzing algorithm which is able to retrieve the helicity, ellipticity, tilt angle and the degree of polarization for the whole spectrum of the target light.

A spectroscopic measurement apparatus includes a pulsed laser light source that emits pulsed laser light, a beam splitter that splits the pulsed laser light into pump light and probe light, a delay circuit that changes a delay time of the pump light with respect to the probe light, a chopper that intensity-modulates the pump light, a wavelength converter that wavelength-converts the probe light into vacuum ultraviolet light, an optical system that guides the pump light and the wavelength-converted probe light to a sample, and a detector that detects the probe light reflected by the sample.

A spectroscopic measurement apparatus includes a pulsed laser light source that emits pulsed laser light, a beam splitter that splits the pulsed laser light into pump light and probe light, a delay circuit that changes a delay time of the pump light with respect to the probe light, a chopper that intensity-modulates the pump light, a wavelength converter that wavelength-converts the probe light into vacuum ultraviolet light, an optical system that guides the pump light and the wavelength-converted probe light to a sample, and a detector that detects the probe light reflected by the sample.

A method and system for testing a liquid sample for an organic compound is disclosed, the method including the steps of collecting the liquid sample from a liquid source; transmitting light having a wavelength of between about 190 nanometers and about 310 nanometers into the liquid sample; measuring absorption/transmission of the light by the organic compound in the liquid sample; and determining a concentration of the organic compound within the liquid sample based on the absorption/transmission of the light by the organic compound. The system can include a spectrophotometer for measuring the absorption of UV light by the organic compound, an ion exchange column for removing ion contaminants from the liquid sample, and a vacuum degasser unit for removing gases and other impurities from the liquid sample.

Apparatus and methods for complex imaging reflectometry and refractometry using at least partially coherent light. Quantitative images yield spatially-dependent, local material information about a sample of interest. These images may provide material properties such as chemical composition, the thickness of chemical layers, dopant concentrations, mixing between layers of a sample, reactions at interfaces, etc. An incident beam of VUV wavelength or shorter is scattered off of a sample and imaged at various angles, wavelengths, and/or polarizations. The power of beam is also measured. This data is used to obtain images of a sample's absolute, spatially varying, complex reflectance or transmittance, which is then used to determine spatially-resolved, depth-dependent sample material properties.

Methods and systems for performing high throughput spectroscopic measurements of semiconductor structures at mid-infrared wavelengths are presented herein. A Fourier Transform Infrared (FTIR) spectrometer includes one or more measurement channels spanning a wavelength range between 2.5 micrometers and 12 micrometers. The FTIR spectrometer measures a target at multiple different angles of incidence, azimuth angles, different wavelength ranges, different polarization states, or any combination thereof. In some embodiments, illumination light is provided by a laser sustained plasma (LSP) light source to achieve high brightness and small illumination spot size. In some embodiments, FTIR measurements are performed off-axis from the direction normal to the surface of the wafer. In some embodiments, a Stirling cooler extracts heat from the detector of an FTIR spectrometer. In another aspect, measurements performed by one or more spectrometer measurement channels are combined with measurements performed by a mid-infrared FTIR spectrometer channel to characterize high aspect ratio structures.

An apparatus and a method for correctly measuring a phase of an extreme ultraviolet (EUV) mask and a method of fabricating an EUV mask including the method are described. The apparatus for measuring the phase of the EUV mask includes an EUV light source configured to generate and output EUV light, at least one mirror configured to reflect the EUV light as reflected EUV light incident on an EUV mask to be measured, a mask stage on which the EUV mask is arranged, a detector configured to receive the EUV light reflected from the EUV mask, to obtain a two-dimensional (2D) image, and to measure reflectivity and diffraction efficiency of the EUV mask, and a processor configured to determine a phase of the EUV mask by using the reflectivity and diffraction efficiency of the EUV mask.