WO2010098740A1 - Système ellipsométrique dans l'infrarouge térahertz et procédé d'utilisation - Google Patents

Système ellipsométrique dans l'infrarouge térahertz et procédé d'utilisation Download PDF

Info

Publication number
WO2010098740A1
WO2010098740A1 PCT/US2009/005346 US2009005346W WO2010098740A1 WO 2010098740 A1 WO2010098740 A1 WO 2010098740A1 US 2009005346 W US2009005346 W US 2009005346W WO 2010098740 A1 WO2010098740 A1 WO 2010098740A1
Authority
WO
WIPO (PCT)
Prior art keywords
detector
thz
source
electromagnetic radiation
rotating
Prior art date
Application number
PCT/US2009/005346
Other languages
English (en)
Inventor
Craig M. Herzinger
Mathias M. Schubert
Tino Hofmann
Martin M. Liphardt
John A. Woollam
Original Assignee
J.A. Woollam Co., Inc.
Univeristy Of Nebraska Board Of Regents Varner Hall
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by J.A. Woollam Co., Inc., Univeristy Of Nebraska Board Of Regents Varner Hall filed Critical J.A. Woollam Co., Inc.
Publication of WO2010098740A1 publication Critical patent/WO2010098740A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/21—Polarisation-affecting properties
    • G01N21/211—Ellipsometry
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
    • G01N21/3581—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light using far infrared light; using Terahertz radiation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J4/00—Measuring polarisation of light
    • G01J4/04—Polarimeters using electric detection means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
    • G01N2021/3595—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light using FTIR

Definitions

  • the present invention relates to ellipsometer and polarimeter systems which comprise a source of electromagnetic radiation, a polarization state generator, a sample supporting stage, a polarization state detector and a detector of electromagnetic radiation, and more particularly is an ellipsometer or polarimeter or the like system which operates in a frequency range between 300 GHz or lower and extending to higher than at least 1 Tera-hertz (THz), and preferably through the Infra-red (IR) range up to, and higher than 100 THz, comprising:
  • THz Tera-hertz
  • IR Infra-red
  • a source such as a backward wave oscillator; a Smith-Purcell cell; a free electron laser, an FTIR source and/or a solid state device; and
  • a detector such as a Golay cell; a bolometer and/or a solid state detector;
  • a polarization state image rotating system comprised of a sequence of an odd number of reflecting elements, such that a polarized electromagnetic beam caused to enter, reflectively interacts with the odd number of reflecting elements and exits in a direction which is essentially non-deviated and non-displaced, with an azimuthally rotated, but otherwise substantially unchanged, polarization state.
  • ellipsometer systems generally comprise means for setting a linear or elliptical polarization state, (typically substantially linear).
  • modern practice of ellipsometry typically involves causing a spectroscopic beam of electromagnetic radiation, in a known state of polarization, to interact with a sample system at at least one angle of incidence with respect to a normal to a surface thereof, in a plane of incidence.
  • a plane of incidence contains both a normal to a surface of an investigated sample system and the locus of said beam of electromagnetic radiation).
  • the practice of ellipsometry further involves proposing a mathematical model of the ellipsometer system and the sample system investigated by use thereof, and experimental data is then obtained by application of the ellipsometer system. This is typically followed by application of a square error reducing mathematical regression to the end that parameters in the mathematical model which characterize the sample system are evaluated, such that the obtained experimental data, and values calculated by use of the mathematical model, are essentially the same.
  • a typical goal in ellipsometry is to obtain, for each wavelength in, and angle of incidence of said beam of electromagnetic radiation caused to interact with a sample system, sample system characterizing PSI and DELTA values, (where PSI is related to a change in a ratio of magnitudes of orthogonal components r /r in said beam of electromagnetic P s radiation, and wherein DELTA is related to a phase shift entered between said orthogonal components r and r ), caused by interaction with said sample system.
  • PSI is related to a change in a ratio of magnitudes of orthogonal components r /r in said beam of electromagnetic P s radiation
  • DELTA is related to a phase shift entered between said orthogonal components r and r
  • an ellipsometer system which is applied to investigate a sample system is, generally, sequentially comprised of:
  • Each of said components b. - i. must be accurately represented by a mathematical model of the ellipsometer system along with a vector which represents a beam of electromagnetic radiation provided from said source of a beam electromagnetic radiation, Identified in a. above)
  • Various conventional ellipsometer configurations provide that a Polarizer, Analyzer and/or Compensator (s) can be rotated during data acquisition, and are describe variously as Rotating Polarizer (RPE), Rotating Analyzer (RAE) and Rotating Compensator (RCE) Ellipsometer Systems. It is noted, that nulling elllpsometers also exist in which elements therein are rotatable in use, rather than rotating.
  • nulling ellipsometer system involves imposing a substantially linear polarization state on a beam of electromagnetic radiation with a linear polarizer, causing the resulting polarized beam of electromagnetic radiation to interact with a sample system, and then adjusting an analyzer to an azimuthal azimuthal angle which effectively cancels out the beam of electromagnetic radiation which proceeds past the sample system.
  • the azimuthal angle of the analyzer at which nulling occurs provides insight to properties of the sample system.
  • data sets can be obtained with an ellipsometer system configured with a sample system present, sequentially for cases vhere other sample systems are present, and where an ellipsometer system is configured in a straight- through configuration wherein a beam of electromagnetic radiation is caused to pass straight through the ellipsometer system without interacting with a sample system.
  • Simultaneous mathematical regression utilizing multiple data sets can allow calibration of ellipsometers and evaluation of sample system characterizing PSI and DELTA values over a range of wavelengths.
  • the obtaining of numerous data sets with an ellipsometer system configured with, for instance, a sequence of sample systems present and/or wherein a sequential plurality of polarization states are imposed on an electromagnetic beam caused to interact therewith, can allow system calibration of numerous ellipsometer system variables.
  • Said 507 reference does contain the words ellipsometry and Golay, but does not describe an ellipsometer system comprising said elements.
  • Patent No. 5,317,618 to Nakahara et al. which contains the words ellipsometer & free electron laser, but does not describe a combination of said elements.
  • Patent to Wang et al., No. 5,914,492 is of interest as it describes free electron lasers used in combination with a Golay cell and Smith-Purcell detectors. However, it does not describe application in ellipsometry or polarimetry.
  • Patent No. 2,985,790 to Kompfner is disclosed as it describes a Backward Wave Oscillator.
  • Patent No. 2,880,355 to Epsztein is disclosed as it describes a Backward Wave Oscillator -
  • Thz electromagnetic radiation in generalized ellipsometry wherein the source of the Thz electromagnetic radiation is a synchrotron located at BESSY, in Germany.
  • Thz electromagnetic radiation in generalized ellipsometry using synchrotron and blackbody radiation
  • Hofmann et al. American Inst. of Physics, 77, 063902-1 through 063902-12, (2006), describes 5 applying Thz electromagnetic radiation in generalized ellipsometry wherein the source of the Thz electromagnetic radiation is a synchrotron and a conventional blackbody.
  • the use of an FTIR source and bolometer is also ⁇ mentioned.
  • Patents disclosed in the Application leading to Patent No. 6,795,184 are:
  • Patent to Herzinger, No. 6,137,618 is disclosed as it describes a Single Brewster Angle Polarizer in the context of multiple reflecting means, and discloses prior art dual Brewster Angle Single Reflective Means Polarizer Systems.
  • Patent, to Herzinger et al., No. 6,084,675 describes an adjustable beam alignment compensator/retarder with application to spectroscopic ellipsometry.
  • Patent No. 6,118,537 to Johs et al. describes a multiple Berek plate optical retarder system.
  • Patent No. 6,141,102 to Johs et al describes a o single triangular shaped optical retarder element .
  • Patent No. 5,946,098 to Johs et al. describes dual tipped wire grid polarizers in combination 25 with various compensator/retarder systems.
  • Patent No. 6,100,981 to Johs et al. describes a dual horizontally oriented triangular shaped optical retarder.
  • Patent No. 6,084,674 to Johs et al. describes a parallelogram shaped optical retarder element.
  • Patent No. 5,963,325 to Johs et al. describes a 2 5 dual vertically oriented triangular shaped optical retarder element.
  • Patent Nos . 7,450,231 and 7,460,230 to Johs et al. are disclosed as they describe deviation 30 angle self compensating compensator systems.
  • Patent to Johs et al., No. 5,872,630 is disclosed as it describes an ellipsometer system in which an analyzer and polarizer are maintained
  • a Patent to Thompson et al. No. 5,706,212 is also disclosed as it teaches a mathematical regression based double Fourier series ellipsometer calibration procedure for application, primarily, in calibrating ellipsometers system utilized in infrared wavelength range.
  • Bi-refringent, transmissive window-like compensators are described as present in the system thereof, and discussion of correlation of retardations entered by sequentially adjacent elements which do not rotate with respect to one another during data acquisition is described therein.
  • a Patent to He et al., No. 5,963,327 is disclosed as it describes an ellipsometer system which enables providing a polarized beam of electromagnetic radiation at an oblique angle-of-Incidence to a sample system in a small spot area.
  • Patent include:
  • a Patent to Coates et al., No. 4,826,321 is disclosed as it describes applying a reflected monochromatic beam of plane polarized electromagnetic radiation at a Brewster angle of incidence to a sample substrate to determine the thickness of a thin film thereupon.
  • This Patent also describes calibration utilizing two sample substrates, which have different depths of surface coating.
  • Patent to Bjork et al., No. 4,647,207 is disclosed as it describes an ellipsometer system which has provision for sequentially, individually positioning a plurality of reflective polarization state modifiers in a beam of electromagnetic radiation.
  • Patent Nos . 4,210,401; 4,332,476 and 4,355,903 are also identified as being cited in the 207 Patent. It is noted that systems as disclosed in these Patents, (particularly in the 476 Patent), which utilize reflection from an element to modify a polarization state can, if such an element is an essential duplicate of an investigated sample and is rotated ninety degrees therefrom, the effect of the polarization state modifying element on the electromagnetic beam effect is extinguished by the sample.
  • Patent to Mansuripur et al., No. 4,838,695 is disclosed as it describes an apparatus for measuring reflectivity.
  • Patents to Rosencwaig et al., Nos. 4,750,822 and 5,596,406 are also identified as they describe systems which impinge electromagnetic beams onto sample systems at oblique angles of incidence.
  • the 406 Patent provides for use of multiple wavelengths and multiple angles of incidence.
  • Patent No. 5,042,951 to Gold et al. is also disclosed.
  • IR-VASE (Reg. TM) 2 Q the IR-VASE (Reg. TM), for many years.
  • Said instrument provides capability from 10 THz to 150 THz and is a Variable Angle, Rotating Compensator system utilizing a Bomen FTIR Spectrometer. Further, it comprises an FTIR Source, and an Odd-Bounce image
  • the present invention is a practical ellipsometer or polarimeter system for application in the range of frequencies between 300 GHz or below and proceeding well into and preferably through the Infrared frequency range.
  • the prior art demonstrates that it is not unknown to propose, or provide a system for, and practice of ellipsometry at Terahertz (THz) frequencies, however, a specific embodiment than makes such possible and which is suitable for general application in Universities and industry etc., has not been previously disclosed.
  • THz Terahertz
  • Synchrotrons have been used to provide THz frequency band electromagnetic radiation in ellipsometers, it is not remotely possible to provide a Synchrotron at every location whereat it is desired to practice THz ellipsometry.
  • the present invention provides combination of many elements, which results in a novel, practical system for general application in the market place.
  • a generally accepted range for what constitutes a Terahertz range of frequencies is from 3 x 10 11 (ie. 300 GHz), to 1.3 x 10 12 (ie. 1.3 Thz ), Hertz.
  • the Terahertz range is sandwiched between the microwave, (the high end of which has a wavelength of 1 millimeter), and the far-infrared, (the long-wavelength edge of which is 100 micrometers), ranges of wavelengths/frequencies.
  • a Smith-Purcell cell is a device which directs an energetic beam of electrons very close to a ruled surface of a diffraction grating. The Q effect on the trajectory of the beam is negligible, but a result is that Cherenkov radiation in the Terahertz frequency range can be created, where the phase velocity of the electromagnetic radiation is altered by the periodic grating.
  • Another source of5 Terahertz radiation is a Free Electron Laser. In this source a beam of electrons is accelerated to relativistic speed and caused to pass through a periodic transverse magnetic field.
  • the array of magnets is sometimes called an undulator or "wiggler" Q as it causes the electrons to form a sinusoidal path.
  • the acceleration of he electrons causes release of photons, which is “synchrotron radiation”.
  • the electron motion is in phase with the field of said released electromagnetic radiation, and5 therefore the fields add coherently.
  • Instabilities in the electron beam resulting from interactions of the oscillations in the undulators lead to emission of electromagnetic radiation, wherein electrons radiate independently.
  • the wavelength of the emitted Q electromagnetic radiation from the electrons can be adjusted by adjusting the energy of the electron beam and/or magnetic field strength of the undulators, to be in the Terahertz range.
  • BWO Backward Wave Oscillator5
  • a vacuum tube system comprising an electron gun that generates an electron beam and causes it to interact with an electromagnetic wave traveling in a direction opposite to that of ejected electrons such that THz frequency oscillations are sustained by interaction between the propagating traveling wave backwards against the electron beam.
  • a Golay cell which operates by converting a temperature change resulting from electromagnetic radiation impinging onto material, into a measurable signal.
  • electromagnetic radiation when electromagnetic radiation is caused to impinge on a blackened material it heats a gas, (eg. Xenon) in an first chamber of an enclosure, and that causes a distortable reflecting diaphram/f ilm adjacent to said first chamber to change shape.
  • a gas eg. Xenon
  • a Bolometer is another detector of monitoring Terahertz range electromagnetic radiation, but operates by using the effect of a changing electric resistance caused by electromagnetic radiation impinging onto a blackened metal.
  • THz pulses can be generated by a bow-tie photoconductive radiation antenna excited by a mode-locked Ti-saphire laser with 80 Fs time width pulses, and a detection antenna can be formed from a dipole-type photoconductive antenna with a 5 micron gap fabricated on thin film LT-GaAs.
  • a company named AB Millimeter in Paris France supplies a system that covers the entire range from 8 GHz to 1000 GHz with solid state source and detector devices.
  • the present invention comprises an ellipsometer or polarimeter system which comprises a selection from the group consisting of:
  • a source of electromagnetic radiation in functional combination with a polarization state generator that provides substantially polarized output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz;
  • a2 a polarization state generator comprising a THz source of electromagnetic radiation that provides substantially polarized output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz;
  • At least one detector of electromagnetic radiation said at least one detector being capable of detecting electromagnetic radiation in a range of between 300 GHz or lower and extending higher than at least 1 T HZ - Said ellipsometer or polarizer system further comprises, between said THz source and said detector, at least one selection from the group:
  • the polarization state generator comprising a THz source of electromagnetic radiation that provides substantially polarized output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz, utilizes natural polarization provided by the THz source and does not require use of a seperate polarizer; whereas said source of electromagnetic radiation in functional combination with a polarization state generator that provides substantially polarized output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz, typically comprises a seperate polarizer.
  • the THz source of electromagnetic radiation can comprise at least one selection from the group consisting of:
  • a backward wave oscillator a Smith-Purcell cell; a free electron laser; and a solid state source device; 0 and preferably further comprises a frequency multiplier means after said THz source of electromagnetic radiation, which frequency multiplier receives electromagnetic radiation output from said THz source, and provides harmonics of said 5 electromagnetic radiation in a range of between said source output fundamental and about 1.6 THz.
  • the ellipsometer or polarimeter system preferably comprises at least one odd-bounce 2 Q polarization state rotation system present between:
  • the odd bounce optical image rotating system can be described as a sequence of an odd number of reflective elements oriented in a manner which causes an entering beam of electromagnetic radiation to reflect from a first thereof onto the second thereof and from the second thereof onto the third thereof etc.
  • said three reflections cause a beam of electromagnetic radiation to emerge from the third reflective element with a rotated linear or partially linear polarization azimuthal angle and in a direction which is not significantly deviated or displaced from the locus of the input beam, even when the odd bounce optical image rotating system is caused to stepwise or continuously rotate about an axis coincident with the locus of the beam of electromagnetic radiation.
  • an odd bounce optical image rotating element system comprising any odd number, (eg. 3, 5, 7 etc.) of reflective elements. It is noted that the greater the number of reflective elements the more normal the angle of incidence a beam can make thereto, and higher angles of incidence cause less aberration effects.
  • Coupling the odd bounce optical image rotating system with a substantially linear polarizing element (which can comprise a source of unpolarized electromagnetic radiation and a polarizer, or can comprise a source that provides polarized electromagentic radiation at its output), provides a polarizer system in which the polarizing element can remain stationary while the azimuthal angle of the polarized beam of electromagnetism exiting therefrom, (as viewed from a position along the locus of an electromagnetic beam caused to enter thereto), is rotated.
  • the detector of electromagnetic radiation in a range between 300 GHz or lower and extending higher than 1 THz can be a selection from the group consisting of: a Golay cell; a bolometer a solid state detector.
  • said ellipsometer or polarimeter system further comprises an FTIR source and a detector for detecting said FTIR frequency output in a frequency range above about 1 THz, and means for selecting between :
  • THz source of electromagnetic radiation and optional frequency multiplier that provides THz
  • said FTIR source that provides output in an IR frequency range above about 1 THz.
  • the detector for detecting said FTIR frequency output in a frequency range above about 1 THz, and in which said detector of electromagnetic radiation in a range between 300 GHz or lower and extending higher than at least 1 THz, are each independently selected from the group:
  • a Golay cell a Golay cell; a bolometer; and a solid state detector.
  • the ellipsometer or polarimeter system has output from said THz source, preferebly with a frequency multiplier in functional combination, so that it overlaps output from said FTIR source in frequency, between at least 1.0 to 1.4 THz.
  • said sources are calibrated such that substantially the same results, (eg. ellipsometric PSI and/or DELTA), are achieved by analyzing output from either of the selected detectors in the frequency range of between about 1.0 to 1.4 THz.
  • a preferred present invention ellipsometer or polarimeter system comprises:
  • an FTIR source of electromagnetic radiation in functional combination vith a polarization state generator, that provides substantially polarized output in a frequency range above about 1 THz;
  • a2 a polarization state generator comprising an FTIR source of electromagnetic radiation which provides substantially polarized output in a frequency range above about 1 THz;
  • a3 a THz source of electromagnetic radiation in functional combination with a polarization state generator, that provides substantially polarized output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz;
  • a polarization state generator comprising a THz source of electromagnetic radiation that provides substantially polarized output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz;
  • THz source of electromagnetic radiation comprises at least one selection from the group consisting of:
  • a backward wave oscillator a Smith-Purcell cell; a free electron laser; and a solid state device;
  • a frequency multiplier for providing harmonics of a fundamental output frequency that provides substantially polarized frequency output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz.
  • said ellipsometer or polarimeter comprises means for selecting between said THz and FTIR sources.
  • Said ellipsometer or polarimeter further comprises :
  • a detector system of electromagnetic radiation comprising at least one selection from the group consisting of: a Golay cell detector; a bolometer detector; a solid state source device.
  • said ellipsometer system further comprises, between said selected source and said selected detector, at least one selection from the group;
  • a selected functional combination of selected source and selected detector is applied to cause electromagnetic radiation to impinge on and interact with a sample on said sample support, then enter said selected detector, to the end that said detector produces an output.
  • said preferred embodiment provides that the output from the functional combination of said selected THz source and preferably a frequency multiplier, and that from said FTIR source overlap in frequency between at least 1.0 to 1.4 THz such that substantially the same results, (eg. ell ipsometric PSI and/or DELTA), are achieved by analyzing output from either of the selected detectors in the frequency range of between about 1.0 to 1.4 THz.
  • substantially the same results eg. ell ipsometric PSI and/or DELTA
  • a prefered present invention system also comprises a chopper for chopping the electromagnetic beam which interacts with the sample, This enables noise reduction, particularly where data is obtained with the system located in a non-darkened room, such that spurious electomagnetic radiation is present.
  • a present invention method of character i2ing a sample comprises the steps of:
  • the present invention method also preferably involves chopping the substantially polarized electromagnetic radiation which is caused to impinge on and interact with said sample on said sample support, and which then proceeds to and enters said selected detector, to the end that said detector provides output based substantially only on the chopped beam content.
  • said method can further comprise performing at least one selection from the group consisting of:
  • Said method can further comprise the step of continuously or step-wise rotating at least one of the at least one odd-bounce polarization state rotation system present between said source and detector, or operating a present electro, acousto or opto-modulator , during data acquisition.
  • the benefit is that, especially in ellipsometer/polarimeter etc. systems which operate in the IR range of wavelengths and below, it can be difficult to cause rotation of a linear polarizer, (or analyzer), without adversely causing deviation of a beam of electromagnetic radiation caused to pass therethrough, or causing mis-coordination of multiple elements thereof, (ie. multiple tipped wire linear polarizer as described in Patent No. 5,946,098).
  • the present invention allows setting fixed substantially linear polarizer, and analyzer azimuthal orientations, and using the odd bounce optical image rotating element instead, to effect different electromagnetic beam azimuthal rotation orientations.
  • a backward wave oscillator a Smith-Purcell cell; a free electron laser; and a solid state device;
  • a frequency multiplier for providing harmonics of a fundamental output frequency that provides substantially polarized frequency output in a frequency range between 300 GHz or lower and extending higher than at least
  • a Golay cell detector a bolometer detector; a solid state source device
  • a preferred embodiment makes use of a backward wave oscillator (BWO) in combination with a multiplier that provides xl, x2 x3 x6 and x9 capability, in functional combination with Golay cell or bolometer, provides good results in the range of from about 0.12 - 1.5 THz.
  • BWO backward wave oscillator
  • a conventional FTIR Source as used in a J. A. Woollam Co. IR-VASE (Reg. TM), to provide 10 - 150 THz capability, has been shown capable of providing output down to about 1.0 Thz .
  • it can be advantagous to cool a detector, (eg. by use of liquid helum), and to adjust beam chopper rate, (eg. between about 12 - 50 Hz), differently for different source and detector combinations.
  • a present invention ellipsometer or polarimeter system which comprises:
  • a2 a polarization state generator comprising a THz source of electromagnetic radiation that provides substantially polarized output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz;
  • At least one odd bounce optical image rotating system which comprises:
  • rotating polarizer rotating compensator
  • rotating analyzer rotating analyzer
  • present invention methodology which involves which the step of providing an ellipsometer or polarimeter system involves the selection of:
  • a2 a polarization state generator comprising a THz source of electromagnetic radiation that provides substantially polarized output in a frequency range between 300 GHz or lower and extending higher than at least 1 THz;
  • providing at least one odd bounce optical image rotating system which comprises:
  • rotating polarizer rotating compensator; rotating analyzer; and said odd-bounce optical image rotating system
  • an ellipsometer or polarimeter system which operates in the THz range, and its method of use, which ellipsometer or polarimeter comprises a chopper to chop the electromagnetic beam and provide substantially only the chopped electromagnetic beam to the detector, and which is in functional combination with at least two rotating elements, each thereof being selected from the group consisting of:
  • rotating polarizer rotating compensator; rotating analyzer; and odd bounce optical image rotating system
  • said THz range ellipsometer or polarimeter system comprises at least one contunuously rotating odd bounce optical image rotating system comprising an odd number of at least three reflective elements oriented such that a beam ot electromagnetic radiation provided by said source of electromagnetic radiation interacts with each of said at least three reflective elements of said at least one odd bounce optical image rotating system and exits therefrom along a non-deviated non-displaced trajectory, said beam of electromagnetic radiation also interacting with a sample system placed on said stage for supporting a sample system, and said analyzer before entering said detector .
  • a present invention system preferably comprises a Computer System which controls element motion, (eg. stepwise or continuous rotation of a Polarizer (P) and/or Compensator (C, C ) and/or Analyzer (A) and/or Odd Bounce Image Rotating System (OB); operation of a Chopper (CH); positioning of a Sample (S); selection of a Source (Sl, S2); selection of a c Detector (Dl, D2, D3 ) ; and operation of a Source (Sl, S2 7 S3) and/or Detector (Dl, D2, D3).
  • element motion eg. stepwise or continuous rotation of a Polarizer (P) and/or Compensator (C, C ) and/or Analyzer (A) and/or Odd Bounce Image Rotating System (OB); operation of a Chopper (CH); positioning of a Sample (S); selection of a Source (Sl, S2); selection of a c Detector (Dl, D2, D3
  • a present invention system comprises a Computer System (CMP) which serves to analyze data provided by a Detector (Dl, D2, D3 ) and Display said data or Q results of analysis thereof.
  • CMP Computer System
  • the present invention can be considered to be a Computer System (CMP) which comprises an Ellipsometer or Polarimeter, which Computer System (CMP) controls operation of elements of said Ellipsometer or Polarimeter to the 5 end that Sample characterizing Data is developed, as well as analysis of said data performed and presentation of said data, or results of analysis thereof .
  • Figs. Ia - Ic show demonstrative configurations for a present invention ellipsometer or polarimeter system.
  • Fig. Id shows an alternative polarization state generator involving a modulator.
  • Figs. 2a - 2d show various aspects of Therahertz frequency Sources.
  • Figs. 2e - 2g show a demonstrative detectors of Terahertz frequencies.
  • Fig. 3a demonstrates an Odd Bounce image rotating system comprising three (3) reflecting elements.
  • Fig. 3b demonstrates an Odd Bounce image rotating system comprising five (5) reflecting elements.
  • Fig. 4 demonstrates a preferred compensator (C) (C 1 ) C 1 ') which has been used in a rotating compensator ellipsometer system for application in the IR range of wavelengths.
  • Fig. 5a demonstrates a combined Non-Brewster Angle and Brewster Angle Polarizer system.
  • Fig. 5b demonstrates a dual tipped wire grid polarizer system.
  • Fig. 6 demonstrates data which can be achieved by application of the Present Invention, including in an overlap frequency range between about 1.0 and 1.4 THZ .
  • Fig. 7 demonstrates displaying data obtained by practice of the present invention using a computer.
  • Figs. Ia, Ib and Ic show various approaches to providing a Present Invention System.
  • Fig Ia shows Three Sources (Sl) (S2) S3), which can each be a backward wave oscillator or a Smith-Purcell cell or a free electron laser or a solid state device.
  • Beam Combiners (BCl) (BC2) (BC3) which serve to direct electromagnetic radiation from Sources (Sl) (S2) S3), respectively, toward a Sample (S), via optional Polarizer (P) / (the natural source polarization can suffice), Odd Bounce Image Rotating System (OB) and Compensator (C).
  • Said optional (P) (OB) (C) components are shown as typically, in combination, being termed a Conventional Polarization State Generator (CPSG) and are included to polarize a beam of electromagnetic radiation provided by a Source (Sl) (S2) S3).
  • CPSG Conventional Polarization State Generator
  • Sl Source
  • S2 Source
  • S3 Source
  • PSG Polarization State Generator
  • Ia also shows that optional (OB 1 ) (C) and (P) components between the Sample (S) and a Detector (Dl) D2).
  • Detectors (Dl) and (D2) have electromagnetic radiation directed thereinto by Beam Splitters/Directors.
  • Source (Sl) (S2) and (S3) can be energized or not so that a beam of electromagnetic radiation progressing toward the Sample (S) comprises various ranges of wavelengths.
  • Source (Sl) can be selected to provide Terahertz (Thz) frequencies
  • Source (S2) selected to provide Infrared (IR) frequencies
  • one or the other can be energized so that only (THz) or (IR) wavelengths are provided, or both can be energized to provide a broad combined range of wavelengths, preferable with an overlap range of between about 1.0 Thz, and 1.4 Thz or higher, Q frequency.
  • Fig. Ia applies to Figs. Ib and Ic, with the exception that the Sources and Detectors are shown as configured differently. In Fig.
  • Ib the Sources (Sl) (S2) (S3) and Detectors (Dl) (D2) (D3) are simply sequentially5 slid into position.
  • Fig. Ic Input Beam Reflecting Means (BRI) and Output Beam Reflecting Means (BRO) are shown as being rotatable to selectively direct electromagnetic radiation from one source or another toward the Sample (S).
  • the Q configurations shown in Figs. Ia - Ic are not to be considered limiting, but rather are demonstrative. For instance, it is possible to choose a Fig. Ia Source selection approach, and a Fig. Ib or Ic Detector selection arrangement etc. And it is within5 the scope of the Present Invention to provide only one Source, (ie.
  • Fig. Ia can be operated with a plurlaity of Sources simultaneosuly turned on to provide an electromagnetic beam which contains a broad frequency range.
  • Detectors eg. a Golay cell or Bolometer.
  • the configuration in Fig. Ia can be operated with a plurlaity of Sources simultaneosuly turned on to provide an electromagnetic beam which contains a broad frequency range.
  • substantially the same results eg. ellipsometric PSI and/or DELTA
  • This not only provides continuity between the lower and upper extents of the frequency range, but provides an approach to assuring accuracy of results. If the same results are achieved using very different sources of electromagnetic radiation, both can be considered to very likely enabling acquisition of good data.
  • Fig. Id is included to disclose that an Alternative Polarization State Generator (APSG) configuration involving an optional Polarizer (P) and a Modulator (MOD), can be applied in the present invention.
  • Such an (APSG) configuration can be employed instead of, or in addition to components in the Conventional Polarization State Generator (CPSG) shown in Figs. Ia - Ic.
  • CPSG Conventional Polarization State Generator
  • MOD 1 Modulator
  • Such an (APSD) configuration can be employed instead of, or in addition to the Conventional Polarization State Detector (CPSD) shown in Figs. Ia - Ic.
  • CPSD Conventional Polarization State Detector
  • Modulators exist, including those which apply an electric signal, or an acoustic signal or an optical signal to effect modulation of a polarization state.
  • Figs. la-Id Also shown in Figs. la-Id is a Chopper (CH).
  • the Chopper (CH) is shown a being located differently in each of Figs. la-Id. This is to indicate that there is no required position, with the only functional requirement being that the beam be chopped thereby.
  • the system which comprises a Chopper (CH) will provide substantially only the chopped electromagnetic beam to the Detector (Dl) (D2) D3).
  • Fig. 2a shows that a Smith-Purcell (SP) cell comprises a Grating (G) and an electron beam (e ⁇ ) passing thereover, with the result being that THz electromagnetic radiation is emitted.
  • Fig. 2b shows that a Free Electron Laser (FE) comprises a sequence of Magnetic Poles (MP), and again an electron beam (e ⁇ ) passing thereover, with the result being that THz electromagnetic radiation is emitted.
  • FE Free Electron Laser
  • FIG. 2c shows a Backward Wave Oscillator (BWO) comprises a Waveguide (WG) through which electromagnetic radiation (EM) is passed in one direction while an electron beam (e ⁇ ) passes therethrough in the opposite direction, again with the result that THz electromagnetic radiation is emitted.
  • WG Waveguide
  • EM electromagnetic radiation
  • e ⁇ electron beam
  • Fig. 2d demonstrates that a Terahertz source, (arbitrarily identified as (Sl)), typically requires that a Frequency Multiplier (M) be present to provide an extended frequency range output, (eg. from 300 GHz or below through at lest 1.4 THz).
  • Sl Terahertz source
  • M Frequency Multiplier
  • an IR range Source of electromagnetic radiation is preferably a Fourier Transform Infrared (FTIR) Source which provides a spectroscopic range of wavelengths.
  • FTIR Fourier Transform Infrared
  • (FTIR) actually refers to an approach in analysis of a spectrum of wavelengths involving use of a means for collecting a multiplicity of wavelengths simultaneously, and application of a Fourier Transform to data, rather than via use of a monochromater .
  • FTIR actually refers to an approach in analysis of a spectrum of wavelengths involving use of a means for collecting a multiplicity of wavelengths simultaneously, and application of a Fourier Transform to data, rather than via use of a monochromater .
  • Odd-Bounce Image Rotation System see Figs.
  • a Golay cell basically comprises two Chambers (CHl) and (CH2).
  • EM electromagnetic radiation
  • DIA Diaphram
  • PB Probe Beam
  • PB Probe Beam
  • PB Probe Beam
  • PB Probe Beam
  • PB Probe Beam
  • PB Probe Beam
  • Fig. 2f shows that a Bolometer (BOL) operates by directing a electromagnetic radiation to impinge on a material ( ) which changes resistance with its temperature.
  • V Voltage Source
  • I Current Detector
  • a change in the current flow indicates that the electromagnetic radiation has heated the material ( ) .
  • Fig. 2g show a demonstrative detector of Terahertz frequencies comprises a P/N junction onto which electromagnetic radiation (EM) is impinged, and which produces a measurable voltage (V).
  • EM electromagnetic radiation
  • V measurable voltage
  • DTGS Deuterated Triglycine Sulfate
  • PVDF Poly-Vinylidene Fluroide
  • Fig. 2g should also be considered to present at least a portion of a solid state Source of Terahertz frequencies, wherein a voltage is applied, and electromagnetic radiation emission results. It is to be understood that Solid State Sources and Detectors for providing and detecting THz and/or IR frequency range electromagnetic radiation can be substituted for, or used in combination with any of the other types of Source and Detector types identified herein).
  • Figs. 3a and 3b there is represented in Fig. 3a a three (3) bounce Odd Bounce image rotating system (OBIRS) comprising three (3) reflective elements (REl), (RE2) and (RE3), oriented with respect to one another such that an input beam of electromagnetic radiation (EMI) exits as an output _
  • OIRS Odd Bounce image rotating system
  • Fig. 3b demonstrates a five (5) bounce odd bounce image rotating system (OBIRS) wherein five reflective elements (REl'), (RE2 1 ) (RE3 1 ), (RE4 1 ) and (RE5') oriented with respect to one another such an input beam of electromagnetic radiation (EMI) exits as an output beam of electromagnetic radiation (EMO) without any deviation or displacement being entered into the locus thereof.
  • OIRS five bounce odd bounce image rotating system
  • EMI input beam of electromagnetic radiation
  • EMO output beam of electromagnetic radiation
  • Fig. 4 demonstrates a preferred compensator (C) (C) for use in a rotating compensator ellipsometer system for application in the IR range of wavelengths.
  • the compensator system comprises, as shown in upright side elevation, first (OSl) and second (OS2) orientation adjustable mirrored elements which each have reflective surfaces. Note the adjustability enabling pivot (PPl) (PP2) mountings.
  • Said compensator system further comprises a third element (TE) which, as viewed in upright side elevation presents with first (ISl) and second (IS2) sides which project to the left and right and downward from an upper point (UP2), said third element (TE) being made of material which provides reflective interfaces on first and second sides inside thereof.
  • TE third element
  • Said third element (TE) is oriented with respect to the first (OSl) and second (OS2) orientation adjustable elements such that in use an input electromagnetic beam of radiation (LB) caused to approach one of said first (OSl) and second (0S2) orientation adjustable mirrored elements along an essentially horizontally oriented locus, is caused to externally reflect therefrom upwardly vertically oriented, (see beam (Rl)) then enter said third element (TE) and essentially totally internally reflect from one of said first and second sides thereof, then proceed along an essentially horizontal locus (see beam (R2)), and essentially totally internally reflect from the other of said first (OSl) and second (0S2) sides and proceed along an essentially downward vertically oriented locus, (see beam (R3)), then reflect from the other of said first (OSl) and second (OS2) adjustable mirrored elements and proceed along an essentially horizontally oriented (LB 1 ) propagation direction locus which is essentially undeviated and undisplaced from the essentially horizontally oriented locus of said input beam of electromagnetic radiation even when said compensator is caused to
  • Figs. 5a and 5b demonstrate systems which can be used as Polarizer (P) and Analyzer (A) in Figs. Ia - Ic.
  • Fig. 5a demonstrates a Polarizer (P) comprised of Non-Brewster Angle (NBR) and Non-Brevster (BR) Angle components. Shown is a beam of electromagnetic radiation (EMW) passing demonstrates a compensator design for optional compensators (C) (C) will be present and caused to rotate during data acquisition and the odd bounce image rotating system (OBIRS) will be stepped to various azimuthal angle positions and set motionless during data acquisition, which the fixed linear polarizer (FP) and analyzer (A) (A 1 ) are held stationary.
  • EMW electromagnetic radiation
  • C compensators
  • OIRS odd bounce image rotating system
  • the preferred present invention application is in a rotating compensator ellipsometer system, wherein the combination of the fixed polarizer and the odd bounce image rotating system (OBIRS) provide an effective rotatable polarizer.
  • OIRS odd bounce image rotating system
  • a polarizer such as tipped wire grid plate polarizers used in the IR wavelength range
  • EMI input
  • EMO output
  • Fig. 5b demonstrates an alternative possible polarizer, comprising a dual tipped wire grid polarizer system comprising first (WGl) and second (WG2) wire grid polarizers which have fast axes of polarization oriented with their fast axes parallel to one another, each thereof having first and second essentially parallel surfaces.
  • first (WGl) and second (WG2) wire grid polarizers which have fast axes of polarization oriented with their fast axes parallel to one another, each thereof having first and second essentially parallel surfaces.
  • the essentially parallel sides of (WGl) are tipped with respect to the essentially parallel sides of (WG2), as characterized by the angle ( ).
  • the purpose of angle ( ) is to divert unwanted reflections (Rl) and (R2).
  • both Polarizers in Figs. 5a and 5b provide substantially undeviated and undisplaced output beams therefrom, vith respect to beams input thereto, even when the polarizer is rotated about the
  • Polarizers provide a linear polarization as output
  • the present invention can be ⁇ ⁇ used with a substantially linearly polarizing polarizer, or a polarizer which provides partially linearly polarization.
  • polarizer should then be interpreted broadly to mean preferably a linear polarizer, but including
  • Fig. 6 shows that a preferred embodiment of the present invention allows sample investigation in both the THz and IR ranges, (eg. from 300 GHz to abut 1.4 THz, and from about 1.0 THz and higher frequency). Further, it is indicated
  • a first (Sl) is used to provide the electromagnetic radiation
  • a second (S2) Source is used to provide the electromagnetic radiation.
  • Fig. 6 shows an overlap in the range of about 1.0 to about 1.4 THZ
  • a present invention system preferably provides the same results, (eg. ellipsometic PSI and/or DELKTA), when Detector output is analyzed to provide, for instance, a Sample characterizing PSI ( ), (or DELTA ( )).
  • Fig. 6 should be viewed 5 as demonstrating a concrete and tangible presentation of results which can be achieved by application of the Present Invention.
  • Fig. 7 demonstrates displaying data (DIS) provided by a Detector (DET), (eg. Dl, D2 D3 in Figs. Ia - Id), obtained by practice of the present invention using machine readable media of a computer (CMP), as well as indicates the Computer (CMP) can control Ellipsometer/Polarimeter elements operation.
  • DET Detector
  • CMP computer

Landscapes

  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Toxicology (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

La présente invention concerne des systèmes ellipsométriques et polarimétriques, et, plus particulièrement, un système ellipsométrique ou polarimétrique, ou similaire, qui fonctionne dans une gamme de fréquences comprise entre 300 GHz au maximum et plus d'au moins 1 térahertz (THz), en passant, de préférence, par la gamme infrarouge (IR) jusqu'à 100 THz et plus, le système comprenant : une source, telle qu'un oscillateur à ondes régressives (BWO); une cellule de Smith-Purcell (PC); un laser à électrons libres (FE) ou une source FTIR et un dispositif à semi-conducteurs; un détecteur, tel qu'une cellule de Golay (GC); un bolomètre (BOL) ou un détecteur à semi-conducteurs, et comprenant, de préférence, au moins un système de rotation d'image d'état de polarisation de type «à rebond impair » (OB) et comprenant facultativement un polariseur (P), au moins un compensateur (C) (C') et/ou un modulateur (MOD), en plus d'un analyseur (A).
PCT/US2009/005346 2009-02-27 2009-09-28 Système ellipsométrique dans l'infrarouge térahertz et procédé d'utilisation WO2010098740A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US20873509P 2009-02-27 2009-02-27
US61/208,735 2009-02-27
US46579109A 2009-06-23 2009-06-23
US12/465,791 2009-06-23

Publications (1)

Publication Number Publication Date
WO2010098740A1 true WO2010098740A1 (fr) 2010-09-02

Family

ID=42665761

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2009/005346 WO2010098740A1 (fr) 2009-02-27 2009-09-28 Système ellipsométrique dans l'infrarouge térahertz et procédé d'utilisation

Country Status (1)

Country Link
WO (1) WO2010098740A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106248615A (zh) * 2015-06-05 2016-12-21 中国科学院苏州纳米技术与纳米仿生研究所 一种太赫兹波检偏器
CN106404181A (zh) * 2016-10-12 2017-02-15 河南师范大学 多功能光谱发射率测量装置及其测量方法
WO2022135763A1 (fr) * 2020-12-21 2022-06-30 Helmut Fischer GmbH Institut für Elektronik und Messtechnik Procédé et dispositif de détermination d'au moins une propriété d'au moins une couche à l'aide d'un rayonnement térahertz

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6795184B1 (en) * 2001-04-06 2004-09-21 J.A. Woollam Co., Inc Odd bounce image rotation system in ellipsometer systems
US6798511B1 (en) * 2000-10-18 2004-09-28 Regents Of The University Of Minnesota Imaging ellipsometry
US20040228371A1 (en) * 2003-04-09 2004-11-18 James Kolodzey Terahertz frequency radiation sources and detectors based on group IV materials and method of manufacture
US20060289761A1 (en) * 2004-12-15 2006-12-28 Bahram Nabet Nanowire based plasmonics
US20070097373A1 (en) * 2000-05-30 2007-05-03 Pfeiffer Galen L System for and method of investigating the exact same point on a sample substrate with multiple wavelengths
US7274450B1 (en) * 2000-03-21 2007-09-25 J.A. Woollam Co., Inc Sample entry purge system in spectrophotometer, ellipsometer, polarimeter and the like systems
US20070252992A1 (en) * 2006-04-28 2007-11-01 Canon Kabushiki Kaisha Apparatus and method for obtaining sample information by detecting electromagnetic wave
US20070278407A1 (en) * 2006-06-02 2007-12-06 Honeywell International Inc. Micromechanical thermal sensor

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7274450B1 (en) * 2000-03-21 2007-09-25 J.A. Woollam Co., Inc Sample entry purge system in spectrophotometer, ellipsometer, polarimeter and the like systems
US20070097373A1 (en) * 2000-05-30 2007-05-03 Pfeiffer Galen L System for and method of investigating the exact same point on a sample substrate with multiple wavelengths
US6798511B1 (en) * 2000-10-18 2004-09-28 Regents Of The University Of Minnesota Imaging ellipsometry
US6795184B1 (en) * 2001-04-06 2004-09-21 J.A. Woollam Co., Inc Odd bounce image rotation system in ellipsometer systems
US20040228371A1 (en) * 2003-04-09 2004-11-18 James Kolodzey Terahertz frequency radiation sources and detectors based on group IV materials and method of manufacture
US20060289761A1 (en) * 2004-12-15 2006-12-28 Bahram Nabet Nanowire based plasmonics
US20070252992A1 (en) * 2006-04-28 2007-11-01 Canon Kabushiki Kaisha Apparatus and method for obtaining sample information by detecting electromagnetic wave
US20070278407A1 (en) * 2006-06-02 2007-12-06 Honeywell International Inc. Micromechanical thermal sensor

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DUERR, ERIK KURT: "Distributed Photomixers", MASSACHUSETTS INSTITUTE OF TECHNOLOGY, PHD DISSERTATION, September 2002 (2002-09-01), pages 136, Retrieved from the Internet <URL:http://dspace.mit.edu/handle/1721.1/16895> [retrieved on 20100509] *
HOFMANN, T. ET AL.: "Hole diffusion profile in a p-p+ silicon homojunction determined by terahertz and midinfrared spectroscopic ellipsometry", DEPARTMENT OF ELECTRICAL ENGINEERING AND NEBRASKA CENTER FOR MATERIALS AND NANOSCIENCE, 20 July 2009 (2009-07-20), UNIVERSITY OF NEBRASKA-LINCOLN, LINCOLN, NEBRASKA 68588-0511, USA, Retrieved from the Internet <URL:http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1097&context=cmrafacpub> [retrieved on 20100509] *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106248615A (zh) * 2015-06-05 2016-12-21 中国科学院苏州纳米技术与纳米仿生研究所 一种太赫兹波检偏器
CN106248615B (zh) * 2015-06-05 2019-04-23 中国科学院苏州纳米技术与纳米仿生研究所 一种太赫兹波检偏器
CN106404181A (zh) * 2016-10-12 2017-02-15 河南师范大学 多功能光谱发射率测量装置及其测量方法
CN106404181B (zh) * 2016-10-12 2019-03-12 河南师范大学 多功能光谱发射率测量装置及其测量方法
WO2022135763A1 (fr) * 2020-12-21 2022-06-30 Helmut Fischer GmbH Institut für Elektronik und Messtechnik Procédé et dispositif de détermination d'au moins une propriété d'au moins une couche à l'aide d'un rayonnement térahertz

Similar Documents

Publication Publication Date Title
US9121757B2 (en) Terahertz ellipsometer system, and method of use
US8169611B2 (en) Terahertz-infrared ellipsometer system, and method of use
US9041927B1 (en) Terahertz-infrared ellipsometer system, and method of use
Kübler et al. Ultrabroadband terahertz pulses: generation and field-resolved detection
JP3550381B2 (ja) 偏光解析装置及び偏光解析方法
US20060231762A1 (en) Reflection type terahertz spectrometer and spectrometric method
EP2446235B1 (fr) Système ellipsométrique infrarouge térahertz et son procédé d&#39;utilisation
US8488119B2 (en) Terahertz-infrared ellipsometer system, and method of use
EP2798322B1 (fr) Ellipsomètre térahertz et procédé d&#39;utilisation
US10073120B1 (en) Integrated vacuum-ultraviolet, mid and near-ultraviolet, visible, near, mid and far infrared and terahertz optical hall effect (OHE) instrument, and method of use
US8934096B2 (en) Terahertz-infrared ellipsometer system, and method of use
US6795184B1 (en) Odd bounce image rotation system in ellipsometer systems
WO2010098740A1 (fr) Système ellipsométrique dans l&#39;infrarouge térahertz et procédé d&#39;utilisation
Alligood DePrince et al. Extending high-finesse cavity techniques to the far-infrared
US8564777B1 (en) System and method for compensating detector non-idealities
US9851294B1 (en) Integrated mid-infrared, far infrared and terahertz optical Hall effect (OHE) instrument, and method of use
McGrane et al. Broadband mid-infrared measurements for shock-induced chemistry
JP2004125712A (ja) 分光分析装置
O'Hara et al. Bloch-wave interferometry of driven quasiparticles in bulk GaAs
Liu et al. Terahertz frequency measurement of far-infrared laser with an improvement of Martin–Puplett interferometer
US11740176B2 (en) Fast and accurate mueller matrix infrared spectroscopic ellipsometer
Kang et al. Time-Resolved Optical Pump-THz Ellipsometer Probe Measurements
Jeong et al. THz imaging by a wide-band compact FEL
Shen et al. Electron-beam bunch length monitor based on electro-optic detection technique
Shen et al. Electron-beam bunch length monitor based on electro-optic detection

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 09840900

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 09840900

Country of ref document: EP

Kind code of ref document: A1