32s红外椭圆偏振测试技术.pptx

SENDIRA Infrared Spectroscopic EllipsometerBasics The ellipsometer measures in reflection mode the optical response of a sample using polarized light.The sample properties change the polarization state of the reflected light.Amplitude ratio and phase difference of the Fresnel reflection coefficients rp and rs are used to investigate material composition,molecule orientation,film thickness and optical constants of single films and layer stacks.Benefits of SENDIRA IR spectroscopic ellipsometerMeasures two parameters:amplitude ratio and phase differencesSensitive to mono layers and molecule orientationEasy sample preparation,no reference sample requiredCombines SE with R and T measurements Large sample analysis,mapping capabilitiesMeasurement principal of FT-IR ellipsometer A(1)P(2)=45 InterferometerEllipsometerFourier transformationInterferogram SourceCompensatorPolarizer SampleAnalyzer DetectorSingle beam spectraEllipsometric Parameters (),()IR spectroscopic ellipsometer SENDIRA Ellipsometer set-up1:Transmitter arm of ellipsometer2:Receiver arm of ellipsometer3:Height and tilt adjustable sample stage4:Auto-collimating telescope and microscope for accurate sample alignment5:Motorized goniometer123454IR spectroscopic ellipsometer SENDIRAWavelength range:400 cm-1 6000 cm-1Separate ellipsometer optics,ellipsometer uses external port of FT-IR instrumentComplete accessible FT-IR spectrometerLarge samples,maximal sample size 200 mm diameter,maximal sample height 8 mmEllipsometric,transmission and reflection measurements with polarized lightVariable incident angle of light(VASE)SENTECH comprehensive software for spectroscopic ellipsometry SpectraRayKey featuresIR spectroscopic ellipsometer SENDIRASENTECHs ellipsometer optics attached to the external port of Varian FT-IR instrumentIR spectroscopic ellipsometer SENDIRASENTECHs ellipsometer optics attached to the external port of Thermo FT-IR instrumentIR spectroscopic ellipsometer SENDIRASpecifications:The ellipsometer has a Polarizer/Sample/Compensator/Analyzer set-up.Highly accurate Step Scan Analyzer Measuring Mode is applied.The compensator measurement offers full ellipsometric information capability.Wavelength range:400 cm-1 6000 cm-1Polarizer,Analyzer:wire grid on KRS-5Compensator:Broadband compensator,KBr:0360 deg,:090 degLight source:Glow barDetector:Peltier cooled DTGS(Deuterated Tri-Glycine Sulfate)MCT detector optionalSpectral resolution:32 1 cm-1 Sample stage:Height and tilt adjustable 150 mm sample platformSample alignment:ACT,very accurate optical methodMeasurement speed:typ.5-10 min for full spectra measurementGoniometer:motorized,40-90 deg/0.01 deg stepsBeam diameter:typ.5 mmSoftware:SpectraRay,(Windows XP,Vista compatible)IR spectroscopic ellipsometer SENDIRAEllipsometric spectra in the MIRWellenzahl cm-1Wellenzahl cm-1Einfallswinkel 0=70SiNX film on Si-wafern=1,99(633 nm)Susceptibility(electrical polarizibility)of the Brendel-oscillator kStandard deviation of the Gaussian distributon cm-1 of the Brendel-oscillator kOcillator frequency cm-1 of Brendel-oscillator kDamping cm-1 of the Brendel-oscillator kOscillator strength cm-1 of the Brendel-oscillators kModeling of absorption bands in the MIRBrendel oscillator model:Modeling of absorption bands in the MIRSi-N stretching vibration,strong oscillator 839 cm-1NSiModeling of absorption bands in the MIRSi-H stretching vibration,weak oscillator 2200 cm-1HSiModeling of absorption bands in the MIRWellenzahl cm-1Wellenzahl cm-1Einfallswinkel 0=70SiNX film on Si-waferth=678 nm,n=1,99(633 nm)SENDIRA Optical constants in the MIR Vibration spectroscopy in the wavelength range:400 cm-1 6000 cm-1 Thickness measurement on rough surfaces Detection of very thin films of very thin films Detection of impurities Composition analysis Doping profiles in silicon(1017 cm-3)Carrier concentrationApplications of MIR ellipsometryOptical constants n,k in the MIRPV glass1:Si-O-Si stretching vibration 1045 cm-12:O-Si-O bending vibration 783 cm-13:Si-O-Si rocking vibration 458 cm-1123Vibration spectroscopy in the MIR(e.g.SiNx film)symmetrical stretching vibrationasymmetric stretching vibrationbending vibrationImaginrteil NH-bending vibration(factor 25)NH-stretching vibration(factor 25)SiH-stretchign vibration(factor 25)SiN-stretching vibrationk 1000 2000 3000 4000 cm-1Wave number/cm-1Transmission spectra usedfor finger print methodNot applicable for absorbing MaterialsEllipsometric measurements determine directly n and kT spectra can be easily calculated from n,k dataDetection of chemical substances by vibration spectroscopyBerreman effect:Generation of LO resonancePossibility of characterizationof very thin filmse.g.dielectric films(SiO2,SiNx)on siliconMeasurement of film thickness25 nm SiO2 on siliconMeasurement of film thicknessPECVD of SiC films using liquid precursorAnalysis of plasma deposition processesHydrogen concentration in PECVD SiNx filmAnalysis of AR coatings for silicon solar cellsH/Si(111)H/Si(001)Mono layer sensitivity of IR ellipsometryN.Esser,ISAS BerlinHydrogen concentration of PECVD deposited non-doped a-Sia-Si on glass700 nmSi-SiSi-SiSi-HSi-HAnalysis of Si-PECVD process for thin film solar cellSn surface treated with HF2 in different concentrations(primer film)Verfication of surface layer by carboxyl group(C=O)(1400-1600 cm-1)Verification of thin organic films on metal surfaceswithout purgingwith purgingMolecule orientation:Guanin on H-passivated Si(111)simulatedN.Esser,ISAS Berlin800100012001400160018000.20.30.40.5tan Wave number/cm-1measuredGuanine(G)Guanine(G)C C5 5H H5 5N N5 5OOWave number/cm-1800100012001400160018000.350.40.45tan Detections of bond orientations of complex moleculesBond orientations:-In plane-Out of plane-IsotropicOrientation of molecules:Langmuir-Blodgett films on goldas grown130C heatedTsankow at al,Infrared ellipsometry of Langmuir-Blodgett filmson gold towards interpreting the molecular orientation“,Langmuir 2002,18,6559K.Hinrichs,ISAS Berlin-20 nm TiO2 film on glass substrate-Thickness measurement in UV-VIS-Measurement of refractive index is not specific for crystal structureCombination on MIR and UV-VIS ellipsometry-TiO2 has two most probably phases:anastas and rutil-The measured absorption behaviour in the MIR is characteristic for the anastas phase Combination on MIR and UV-VIS ellipsometryTCO Film:Al:ZnO(AZO)on glassThickness:735 nmRs:5 Ohm squareCombination on MIR and UV-VIS ellipsometryArsen doped Silicon wafersDrude Model:Plasma frequency:1746 cm-1Damping:359 cm-1Carrier concentration:8.8 x 10+18/cm3Mobility100 cm2/VsCarrier concentration and profileSi substrateEpi-SiliconInterfaceCarrier concentration and profileP-Dotierungsprofils in Si solar cellsCarrier concentration and profileSample 1Sample 2The IR ellipsometry is a powerful analysis method.It is especially suited for thin organic and inorganic films.There are applications in quite different fields.The combination of ellipsometer optics with commercial FT-IR is a big benefit of SENDIRA because there are a lot of FT-IR instruments used for material analysis.The markets are institutes for material research,chemistry,and biotechnology as well as manufacturer of IR devices and opticsSummary