WO1995017662A1 - Ellipsometre spectroscopique rapide - Google Patents

Ellipsometre spectroscopique rapide Download PDF

Info

Publication number
WO1995017662A1
WO1995017662A1 PCT/EP1994/004235 EP9404235W WO9517662A1 WO 1995017662 A1 WO1995017662 A1 WO 1995017662A1 EP 9404235 W EP9404235 W EP 9404235W WO 9517662 A1 WO9517662 A1 WO 9517662A1
Authority
WO
WIPO (PCT)
Prior art keywords
acousto
radiation beam
measuring
filter
radiation
Prior art date
Application number
PCT/EP1994/004235
Other languages
German (de)
English (en)
Other versions
WO1995017662B1 (fr
Inventor
Wolfgang Fukarek
Original Assignee
MAX-PLANCK-Gesellschaft zur Förderung der Wissenschaften e.V.
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 MAX-PLANCK-Gesellschaft zur Förderung der Wissenschaften e.V. filed Critical MAX-PLANCK-Gesellschaft zur Förderung der Wissenschaften e.V.
Priority to EP95905090A priority Critical patent/EP0736171A1/fr
Publication of WO1995017662A1 publication Critical patent/WO1995017662A1/fr
Publication of WO1995017662B1 publication Critical patent/WO1995017662B1/fr

Links

Classifications

    • 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
    • G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
    • G01J3/28—Investigating the spectrum
    • G01J3/447—Polarisation spectrometry
    • 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

Definitions

  • the invention relates to an ellipsometric measuring method according to the preamble of claim 1 and a device for carrying it out.
  • Ellipsometry is an optical method of investigation, particularly in solid-state and surface physics, in which totally polarized light of a certain wavelength strikes the sample at a relatively large angle of incidence (close to the angle of total reflection).
  • the reflected light is generally elliptically polarized.
  • the polarization state of the reflected light characterized by the direction and ratio of the main axes, and possibly also the absolute value of the amplitude are measured.
  • ellipsometry is used to measure the optical constants and the thickness of thin layers, e.g. Oxide layers and films. It is also possible to analyze multilayer systems and inhomogeneous or anisotropic layers. Ellipsometric measurements can also be used for structure elucidation (roughness, density, microcrystallinity, composition).
  • a laser or a combination of several lasers is very often used as the light source.
  • the quite simple construction of these devices is advantageous since no dispersive elements are required.
  • the high intensity and quality of the laser beam is also advantageous.
  • the main disadvantage of these egg lipometers is that spectroscopic measurements are in principle not possible with these designs.
  • the measuring light wavelength is not freely selectable.
  • spectroscopic egg lipometers A large number of different arrangements are known for spectroscopic egg lipometers. The most widespread is the use of grating monochromators or grating / prism monochromators as the dispersive element and a Xe short-arc lamp or a halogen lamp as the light source. It is advantageous with these arrangements that monochromators are available which cover a very large spectral range (for example 200 ... 2000 nm), the order filters being changed automatically. These devices can also be used for real-time in-situ measurements if the monochromator is set to a fixed wavelength. If, however, measurements are to be carried out with several wavelengths, the achievable measuring speed decreases sharply due to the time required to move the grating (and possibly a filter).
  • the parallel measuring light beam must be focused on the input slit.
  • the quality of the optics used and the maximum permissible slit opening at the desired spectral resolution intensity losses in the measuring light can occur as a result.
  • the present invention consists in an ellipsometric measuring method with which in situ both time-resolved with any number of freely selectable measuring light wavelengths and non-time-resolved measurement can be carried out quasi-continuously without the need for a modification on the device.
  • the invention has the advantage that the number and position of the measuring light wavelengths can be freely selected.
  • the time required for setting the measuring light wavelength is considerably shortened compared to the methods known in the prior art and is independent of the previously set measuring light wavelength. It is not necessary to focus on an entry slit.
  • Figure 1 is a schematic overall view of the ellipsometric measurement setup according to the invention.
  • FIG. 2 shows a schematic overall view of an alternative embodiment of the ellipsometric measurement setup according to the invention.
  • Fig. 3 is a schematic representation of the operation of an acousto-optical filter.
  • the measuring setup shown in FIG. 1 contains a spectrally broadband radiation source 1, such as a xenon lamp, with a spectral characteristic which preferably covers the entire visible and parts of the infrared spectral range.
  • the broadband radiation beam is coupled into an optical waveguide 2, which is connected to an objective 3.
  • the objective 3 is used to prevent the divergent radiation emerging from the optical waveguide 2 parallelize bundles or focus on the sample.
  • a zoom lens can be used as the lens 3.
  • a spectrally narrow-band, linearly polarized radiation beam is diffracted from the broadband input radiation. This is post-polarized with a polarizer 5, whereupon it strikes the flat surface of a sample 6 to be examined.
  • the reflected radiation beam is generally elliptically polarized and strikes an analyzer 7 whose direction of polarization can be changed.
  • the radiation intensity of the reflected radiation beam is measured behind the analyzer 7 by a radiation detector 8.
  • the output signal of the radiation detector 8 is fed to a current-voltage converter / amplifier 9 or an analog / digital converter. Its output signal is fed into an input of a personal computer (PC) 10 and further processed there with suitable computer programs.
  • PC personal computer
  • the polarization direction of the analyzer 7 is varied and the dependence of the radiation intensity on the angular position of the analyzer 7 is measured.
  • FIG. 2 shows an alternative embodiment of an egg lipometer according to the invention.
  • the acousto-optically tunable filter (4) is arranged in the beam path behind the sample (6) in a modification of the measurement setup according to FIG. 1.
  • the sample (6) is thus irradiated with spectrally broadband radiation, the wavelength selection only being carried out with the radiation beam reflected on the sample.
  • the acousto-optically tunable filter (4) as shown here, is arranged between the analyzer (7) and the radiation detector (8).
  • a phase-modulating element for example an electro-optical retarder, is used instead of a rotating polarizer or analyzer.
  • a non-collinear acousto-optical filter 4 is shown schematically in FIG.
  • Such a filter is known per se in the prior art and e.g. in the company name "AOTF SPECTROSCOPY” by BRIMROSE, 5020 Campbell Boulevard. , Baltimore, MD 21236.
  • the filter essentially consists of a TeO "crystal 43 with two plane-parallel ground end faces.
  • An ultrasonic transducer 42 is applied on one side.
  • the ultrasonic transducer is e.g. a piezoelectric transducer that converts an electrical signal from a high-frequency generator 41 into ultrasonic waves.
  • Ultrasound waves 44 generated in this way propagate in the acousto-optical medium and are absorbed in an acoustic absorber 45 attached to the opposite crystal surface.
  • the spectrally broadband radiation beam 46 falls into the crystal with a small angle of inclination against the ultrasonic wave front.
  • two diffracted, linearly polarized and monochromatic radiation beams 48 and 49 are generated.
  • the non-diffracted radiation beam 47 (zero order) and the diffracted radiation beam 49 are masked out by means of a diaphragm device 50.
  • the monochromatic radiation beam 48 is used for the measurement.
  • the wavelength of the diffracted radiation beams 48 and 49 can be adjusted.
  • An angle dependency of the diffracted radiation beam of the wavelength can be corrected by using a prism positioned behind the filter.
  • a non-collinear filter is a preferred embodiment of the present invention.
  • a collinear type filter can also be used.
  • the number and position of the measuring wavelengths are determined beforehand for a measuring process.
  • Each of these measuring wavelengths corresponds to a specific electrical signal frequency to be set on the high-frequency generator 41. This can of course be done, on the one hand, by manually operating the high-frequency generator 41.
  • a personal computer PC 10 can also be connected to the high-frequency generator 41 by a signal line 11. In this way, the wavelength selection can be controlled by the PC. This can be done by manually entering the next measuring wavelength to be selected on the keyboard of the PC, whereupon the PC sends a signal to the high-frequency generator via the signal line 11 for setting the required high-frequency electrical frequency.
  • an automatic measuring program can also run on the PC 10, which contains the measuring wavelengths to be used.
  • the program automatically calls the next measurement wavelength and sends a corresponding signal to the high-frequency generator 41 via the signal line 11.
  • the sequence of the measuring process for a measuring wavelength can be indicated to the measuring program in a suitable manner, for example by the current-voltage converter / amplifier 9.
  • the setting of the measuring Wavelength can thus occur very quickly and in a purely electronic way without mechanically moving parts and without changing the geometry of the measuring light beam.
  • Another advantage of the method according to the invention is that focusing on an entrance slit, e.g. when using a grating monochromator, is not required. Rather, in the present case, the measuring beam with its beam cross section traverses the acoustically optically tunable filter.
  • Another advantage of the method according to the invention is that the light intensity striking the radiation detector 8 can be electronically controlled.
  • the spectral intensity distribution of the light source, the spectral dependence of the absorption of the optical components of the egg lipometer and the spectral sensitivity of the detector can be compensated so that the signal measured at the detector has no significant spectral dependency, so that the maximum dynamic range of the analog / Digital converter can be used.
  • the control of the light intensity can e.g. by varying the radiation cross section of the spectrally broadband radiation beam in the acousto-optical filter or by varying the signal amplitude of the voltage signal generated in the high-frequency generator 41. In this case, information about the required signal amplitude is transmitted on the signal line 11 in addition to the information required for the wavelength selection.

Landscapes

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

Abstract

L'invention concerne un procédé de mesure ellipsométrique très rapide s'utilisant pour un nombre et une séquence quelconques de longueurs d'onde lumineuses à mesurer, notamment pour effectuer des mesures in situ de processus à la surface d'un substrat. Pour sélectionner rapidement les longueurs d'onde, on utilise une source de rayonnement (1) à large bande et un filtre (4) accordable de manière opto-acoustique et pouvant être modulé par un OP (10).
PCT/EP1994/004235 1993-12-20 1994-12-20 Ellipsometre spectroscopique rapide WO1995017662A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP95905090A EP0736171A1 (fr) 1993-12-20 1994-12-20 Ellipsometre spectroscopique rapide

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEP4343490.8 1993-12-20
DE19934343490 DE4343490A1 (de) 1993-12-20 1993-12-20 Schnelles spektroskopisches Ellipsometer

Publications (2)

Publication Number Publication Date
WO1995017662A1 true WO1995017662A1 (fr) 1995-06-29
WO1995017662B1 WO1995017662B1 (fr) 1995-08-03

Family

ID=6505542

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1994/004235 WO1995017662A1 (fr) 1993-12-20 1994-12-20 Ellipsometre spectroscopique rapide

Country Status (3)

Country Link
EP (1) EP0736171A1 (fr)
DE (1) DE4343490A1 (fr)
WO (1) WO1995017662A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19545018A1 (de) * 1995-12-02 1997-06-05 Marcel Kastler Computergesteuertes Polarimeter zur Drehwinkelbeobachtung von Reaktionen unter konstanten Versuchsbedingungen
US6958858B2 (en) 2001-07-30 2005-10-25 Leica Microsystems Heidelberg Gmbh Method for scanning microscopy; and scanning microscope
US7570358B2 (en) 2007-03-30 2009-08-04 Asml Netherlands Bv Angularly resolved scatterometer, inspection method, lithographic apparatus, lithographic processing cell device manufacturing method and alignment sensor

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10207163A1 (de) * 2002-02-20 2003-08-28 Applied Films Gmbh & Co Kg Vorrichtung und Verfahren für die indirekte Bestimmung der physikalischen Eigenschaften dünner Schichten auf einem nicht-metallischen Substrat mittels Ellipsometrie
DE102006033083B4 (de) * 2006-07-14 2014-01-09 Von Ardenne Anlagentechnik Gmbh Verfahren und Vorrichtung zur Reinigung von Substratoberflächen

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2431976A1 (de) * 1973-07-03 1975-01-23 Matsushita Electric Ind Co Ltd Akusto-optisches filter
US4866264A (en) * 1988-10-31 1989-09-12 Northrop Corporation Method and apparatus for measuring non-reciprocal loss of thin magnetic films and magnetic mirrors
US5131742A (en) * 1990-10-12 1992-07-21 Westinghouse Electric Corp. Acousto-optic spectrometer/polarimeter

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5240388A (en) * 1975-09-26 1977-03-29 Nippon Kogaku Kk <Nikon> Spectroscopic autoellipsometer
JPS6052706A (ja) * 1983-08-31 1985-03-26 Nippon Kokan Kk <Nkk> 膜厚測定装置
FR2595471B1 (fr) * 1986-03-06 1988-06-10 Production Rech Appliquees Dispositif d'ellipsometrie spectroscopique a fibres optiques

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2431976A1 (de) * 1973-07-03 1975-01-23 Matsushita Electric Ind Co Ltd Akusto-optisches filter
US4866264A (en) * 1988-10-31 1989-09-12 Northrop Corporation Method and apparatus for measuring non-reciprocal loss of thin magnetic films and magnetic mirrors
US5131742A (en) * 1990-10-12 1992-07-21 Westinghouse Electric Corp. Acousto-optic spectrometer/polarimeter

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
HARRIS ET AL.: "SIGNAL LEVEL REGULATION AND DARK CURRENT COMPENSATION FOR WAVELENGTH-SCANNING ELLIPSOMETER", IBM TECHNICAL DISCLOSURE BULLETIN, vol. 21, no. 2, pages 855 - 856 *
PIEL ET AL.: "THE FASTEST REAL TIME SPECTROSCOPIC ELLIPSOMETRY: APPLICATIONS AND LIMITATIONS FOR IN SITU AND QUALITY CONTROL", THIN SOLID FILMS, vol. 233, no. 1/2, 12 October 1993 (1993-10-12), LAUSANNE, CH, pages 301 - 306 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19545018A1 (de) * 1995-12-02 1997-06-05 Marcel Kastler Computergesteuertes Polarimeter zur Drehwinkelbeobachtung von Reaktionen unter konstanten Versuchsbedingungen
US6958858B2 (en) 2001-07-30 2005-10-25 Leica Microsystems Heidelberg Gmbh Method for scanning microscopy; and scanning microscope
US7570358B2 (en) 2007-03-30 2009-08-04 Asml Netherlands Bv Angularly resolved scatterometer, inspection method, lithographic apparatus, lithographic processing cell device manufacturing method and alignment sensor
US8031337B2 (en) 2007-03-30 2011-10-04 Asml Netherlands B.V. Angularly resolved scatterometer

Also Published As

Publication number Publication date
DE4343490A1 (de) 1995-06-22
EP0736171A1 (fr) 1996-10-09

Similar Documents

Publication Publication Date Title
DE69938134T2 (de) Spektroskopisches ellipsometer
DE69930651T2 (de) Vorrichtung zur optischen charakterisierung eines dünnschichtmaterials
EP0476088B1 (fr) Spectrometre acousto-optique a double faisceau accordable
EP0019088B1 (fr) Procédé ellipsométrique et dispositif ellipsométrique pour l&#39;étude des propriétés physiques d&#39;une surface d&#39;un échantillon
DE112010004023B4 (de) Filmdickenmessvorrichtung und Filmdickenmessverfahren
EP0163176B1 (fr) Procédé et appareil ellipsométriques pour l&#39;étude des propriétés physiques d&#39;échantillons ou des couches superficielles d&#39;échantillons
DE60209672T2 (de) Auf Flüssigkristallen basierendes polarimetrisches System, Verfahren zu seiner Kalibrierung, und polarimetrisches Messverfahren
EP0195039B1 (fr) Arrangement de mesure pour l&#39;analyse des rayonnements electromagnetiques
DE2935716A1 (de) Verfahren und vorrichtung zum messen der dicke eines films durch ausnutzung von infrarot-interferenzerscheinungen
WO1997009594A1 (fr) Procede et dispositif permettant de mesurer des faisceaux lumineux
EP3411680B1 (fr) Spectromètre miniature et procédé de commutation d&#39;un spectromètre miniature entre un mode de reproduction et un mode spectromètre
DE2537237A1 (de) Laserabsorptionsspektrometer und verfahren der laserabsorptionsspektroskopie
EP3042232A1 (fr) Microscope à balayage et séparateur de faisceau principal acousto-optique destiné à un microscope à balayage
EP1507137B1 (fr) Procédé et dispositif pour l&#39;inspection dépendante de la polarisation et pour l&#39;inspection par résolution spatiale d&#39;une surface ou d&#39;une couche
DE102005023302B4 (de) Vorrichtung und Verfahren zur Messung der Krümmung einer Oberfläche
DE112017008083B4 (de) Ferninfrarotlichtquelle und ferninfrarotspektrometer
DE4105192A1 (de) Polarimetrisches verfahren und vorrichtung zur bestimmung von eigenschaften von materialoberflaechen und transparenten materialien sowie zur winkelmessung
DE2212498A1 (de) Raman-Spektrometer
WO1995017662A1 (fr) Ellipsometre spectroscopique rapide
DE19522188C2 (de) Verfahren und Vorrichtung zur Bestimmung der Dicke und/oder des komplexen Brechungsindexes dünner Schichten und Verwendung zur Steuerung von Beschichtungsverfahren
EP3812697A1 (fr) Dispositif et procédé de mesure de profil d&#39;objets plans pourvus de matériaux inconnus
EP3035034B1 (fr) Système de détection d&#39;anisotropie de réflexion
EP1892508A1 (fr) Agencement pour un système optique en vue d&#39;une spectroscopie optique dépendant de la polarisation résolue dans le temps, système de mesure optique et procédé d&#39;examen spectroscopique dépendant de la polarisation d&#39;une lumière mesurée
EP4094066B1 (fr) Procédé de fonctionnement d&#39;un dispositif de mesure de polarisation et dispositif de mesure de polarisation
DE2453424A1 (de) Tragbares polarisations-analysegeraet

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
ENP Entry into the national phase

Ref country code: US

Ref document number: 1996 663270

Date of ref document: 19960619

Kind code of ref document: A

Format of ref document f/p: F

WWE Wipo information: entry into national phase

Ref document number: 1995905090

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1995905090

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1995905090

Country of ref document: EP