Thin Film Metrology (Ellipsometry, Reflectometry)


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Spectroscopic Ellipsometry | Software | Laser Ellipsometry | Spectroscopic Reflectometry

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SENresearch 4.0 now has widest spectral range available - The SENresearch 4.0 can be configured with a spectral range of 190nm (DUV) - 3500nm (NIR) giving it the widest range available on the market. A high spectral resolution allows measurement of films up to 200µm thick using FTIR ellipsometry. Read more...

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Featured Application Note

Measurement of thick films from 1 to 25µm - The accessible film thickness range in spectroscopic ellipsometry using SENTECH SENresearch 4.0 ellipsometer family is extremely wide. This application note will discuss the film thickness range from 1.0 μm to 14 μm of a photoresist film and a SiO2 film of 25 μm thickness.. Read more...

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Thin Film Metrology

Spectroscopic Ellipsometers | Software | Laser Ellipsometer | Spectroscopic Reflectometry

The SENTECH Instruments thin film metrology range comprises Spectroscopic Ellipsometers, Laser Ellipsometers and Reflectometers. SENTECH Instruments have over 25 years of experience in the thin film industry and are known for high quality, reliability and excellent service.

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Spectroscopic Ellipsometers

Spectroscopic ellipsometers also known as variable wavelength ellipsometers sit at the top of the SENTECH Instruments thin film metrology range. Both extremely thick and thin films can be measured.

SENresearch 4.0 | Spectral Range Up To 190nm - 3500nm

SENresearch 4.0 Spectroscopic Ellipsometer

Widest spectral range and highest spectral resolution: The SENresearch 4.0 spectroscopic ellipsometer covers the widest spectral range from 190 nm (deep UV) to 3,500 nm (NIR). High spectral resolution is offered to analyse even thick films up to 200 µm thickness using FTIR ellipsometry.

No moving parts with SSA principle: There are no moving optical parts during data acquisition for best measurement results. The Step Scan Analyzer (SSA) principle is a unique feature of the SENresearch 4.0 spectroscopic ellipsometer.

Full Mueller matrix by innovative 2C design: The extension of the SSA principle by the innovative 2C design allows measurement of the full Mueller matrix. The 2C design is a field upgradable and cost-effective accessory.

SpectraRay/4 comprehensive ellipsometry software: The SpectraRay/4 is the full-featured software package for advanced material analysis. SpectraRay/4 comprises the Interactive Mode for research with guided graphical user interface and the Recipe Mode for routine applications.

The SENresearch 4.0 is the new SENTECH spectroscopic ellipsometer. Every individual SENresearch 4.0 spectroscopic ellipsometer is a customer-specific configuration of spectral range, options and field upgradable accessories.

SENresearch 4.0 uses fast FTIR ellipsometry for the NIR up to 2,500 nm or 3,500 nm, respectively. It provides broadest spectral range with best S/N ratio and highest, selectable spectral resolution. Silicon films up to 200 µm thickness can be measured. The measurement speed of FTIR ellipsometry compares to diode array configurations, which are also selectable up to 1,700 nm.

The new motorized Pyramid Goniometer features an angle range from 20 deg to 100 deg. Optical encoders ensure highest precision and long term stability of angle settings. The spectroscopic ellipsometer arms can be moved independently for scatterometry and angle resolved transmission measurements.

SENresearch 4.0 operates on the Step Scan Analyser (SSA) principle. The SSA decouples the intensity measurement from mechanical movement, thereby allowing analysis of even rough samples. All optical parts are at rest during data acquisition. Furthermore, the SENresearch 4.0 includes a fast measurement mode for mapping and in situ applications.

Customized ellipsometers of the SENresearch 4.0 can be configured for standard and advanced applications. Examples are dielectric layer stacks, textured surfaces, optical and structural (3D) anisotropic samples. Predefined recipes are provided for a large variety of applications.

SENpro | Affordable Spectroscopic Ellipsometer

SENpro Spectroscopic Ellipsometer

Cost-efficiency The SENpro is a cost-effective spectroscopic ellipsometer without compromising advanced measurement performance.

Discrete angle of incidence: The spectroscopic ellipsometer SENpro comprises a goniometer with discrete angles of incidence in 5°-steps (40° – 90°) to optimize the ellipsometric measurement.

Step Scan Analyzer principle: The unique Step Scan Analyzer principle is featured by SENpro. During data acquisition, polarizer and compensator are fixed to provide highest accuracy of the ellipsometric measurement.

The spectroscopic ellipsometer SENpro features simple operation, measurement speed, and combined data analysis of ellipsometric measurements at different angles of incidence. It measures in the spectral range of 370 nm to 1,050 nm. The spectral range of the SENpro in combination with the sophisticated software SpectraRay/4 allows determining thickness and refractive index of single films and complex layer stacks with ease.

The cost-effective, table top SENpro comprises the VIS-NIR ellipsometer optics, 5°-step goniometer, sample platform, laser alignment, fiber coupled stabilized light source, and detection unit. The SENpro comes with the spectroscopic ellipsometer software SpectraRay/4 for system control and data analysis including modeling, simulation, fitting, and presentation of data. Ready-to-use application files make the operation very easy even for beginners. SpectraRay/4 supports computer controlled mapping for uniformity measurements.

The SENpro is focused on speed and accuracy for the measurement of thin films wherever they are applied. Applications range from extreme thin layers of 1 nm to thick layers up to 15 μm.

For a large variety of applications, predefined recipes are offered by SpectraRay/4.

SENDIRA | FTIR Infrared Spectroscopic Ellipsometer

SENDIRA FTIR Infrared Spectroscopic Ellipsometer

Ellipsometric vibrational spectroscopy: The composition of thin layers is analyzed using the absorption bands of molecular vibrational modes in the infrared spectrum. Also the carrier concentration can be measured with this FTIR spectroscopic ellipsometer.

Fully applicable FTIR: Infrared ellipsometer optics are attached to the commercial FTIR spectrometer. The spectrometer is available for general vibrational spectroscopy as well.

The spectroscopic ellipsometer SENDIRA measures thin film thickness, refractive index, extinction coefficient, and related properties of bulk materials, single layers, and multi-layer stacks. Especially layers below covering layers that are non-transparent in the visible range are now accessible for measurement. Composition of materials and orientation of larger molecule groups and chains can be analyzed.

The SENTECH ellipsometer SENDIRA is especially designed for the infrared (FTIR). The compact table top instrument comprises the purged ellipsometer optics, computer controlled goniometer, horizontal sample platform, auto-collimating telescope, commercial FTIR, and DTGS or MCT detector. The FTIR provides excellent precision and high resolution in the spectral range from 400 cm-1 to 6,000 cm-1 (1.7 µm – 25 µm).

The spectroscopic ellipsometer SENDIRA is focused on the vibrational spectroscopic analysis of thin layers. Applications range from dielectric film, TCOs, semiconductors to organic layers. The SENDIRA is operated by SpectraRay/4 software. FTIR software is provided additionally.

SENDURO | Automated Spectroscopic Ellipsometry

SENDURO Automated Spectroscopic Ellipsometer

Auto-alignment: The fully automated spectroscopic ellipsometry featured by the ellipsometer SENDURO® relieves the user from manually aligning the sample by height and tilt required for highly precise and repeatable spectroscopic ellipsometry. The patented automatic alignment sensor strongly reduces operation errors, works for transparent and reflective samples, and makes automatic maps possible even on bent wafers.

Easy operation: The recipe mode is perfectly suited for routine applications in production, process monitoring as well as R & D. This spectroscopic ellipsometry system comes with a number of ready to use recipes which can be modified for your specific needs.

Step Scan Analyzer principle: The Step Scan Analyzer principle is a unique feature of SENTECH`s spectroscopic ellipsometry. The total time to analyze a sample takes only a few seconds.

The SENDURO® measures refractive index and thickness of single films and layer stacks on transparent and reflective substrates. High sample throughput rate, minimized installation effort, and low cost of maintenance are the real economic advantages of the SENDURO® mapping tool. The mapping of this spectroscopic ellipsometry tool features predefined or user defined patterns, extensive statistics, and graphical display of data.

The SENDURO® represents the SENTECH automated, small footprint, and compact design ellipsometer. The table top instrument comprises the ellipsometer optics, automatic tilt and height sensor, motorized sample stage, and controller electronics, all combined in one compact housing. For highest throughput of our spectroscopic ellipsometry tools cassette loading is offered for up to 300 mm large wafers.

The SENDURO® excels in industrial applications with its sample throughput rate, easy operation, and auto-alignment. Applications range from dielectric films on semiconductors to multi-layer optical coatings on glass.

The SENDURO® software for excellent spectroscopic ellipsometry features a recipe mode and an engineering mode. The recipe mode is dedicated to easy execution of repetitive applications. Password controlled user login allows for different excess levels. In interactive mode, ellipsometric measurements are enhanced by an interactive, guiding graphic user interface. Furthermore, it is possible to modify already existing recipes or to set-up new recipes using the large database of materials and dispersion models.

SpectraRay/4 | Spectroscopic Ellipsometry Software

Simulation: Measurement parameters may be simulated as function of wavelength, photon energy, reciprocal centimeter, angle of incidence, time, temperature, thin film thickness measurement, and other parameters.

Mapping: The mapping option of our spectroscopic ellipsometry features predefined or user defined patterns, extensive statistics, and graphical display of data as 2D color, gray, contour, +/- deviation from mean value and 3D plot.

Interactive Mode:

Setting measurement parameters and starting thin film thickness measurement

Building a model by drag and drop from a materials library or from already existing dispersion models

Defining and varying parameters to fit the calculated spectra to the measured spectra

Interactively improving the model for best figure of merit

Reporting the results as a word document by selecting from predefined or customized templates

Saving all experimental data, the protocol, and comments in one experiment file

Recipe Mode:

The advantage of SpectraRay/4 recipe mode is a two step action:

  • Selection and
  • Execution of predefined recipes from a library.

The recipes comprise thickness measurement parameters, models, fitting parameters, and reporting templates.

SpectraRay/4, the SENTECH proprietary spectroscopic ellipsometry software, includes data acquisition, modeling, fitting, and extended reporting of ellipsometric, reflection, and transmission data. It supports variable angle, multi-experiment, and combined photometric measurements. SpectraRay/4 includes a huge library of materials data based on SENTECH thickness measurements and literature data as well. The large number of dispersion models allows modelling of nearly any type of material.

SpectraRay/4 provides a user-friendly workflow oriented interface to operate SENTECH spectroscopic ellipsometry tools and a comprehensive set of tools to model, fit, and represent ellipsometric data. The user interface incorporates a recipe oriented operation for operators and an advanced mode for interactive measurement and modelling.

SpectraRay/4 features uniaxial and biaxial anisotropic material measurements, thin film thickness measurement, and the measurement of layers. The software treats sample effects like depolarization, non-uniformity, scattering (Mueller-matrix), and backside reflection.

SpectraRay/4 includes all utilities of general spectroscopic ellipsometry software package for data import and export (ASCII included), file management, arithmetic manipulations of spectra, display, printing, and reporting (in Word file format *.doc). The scripting capability makes it very flexible to automate routine measurements, tailor it for demanding applications, and control third party hardware like sensors, heating stage, sample cell or cryostat.

Laser Ellipsometers


SE 400adv | Multiple Angle Laser Ellipsometer

Multiple angle laser ellipsometer SE 400adv

Sub-Angstrom accuracy: The stabilized HeNe laser guarantees a precision of 0.1 Å for thin film thickness measurement of ultra thin single layers.

Push the limits of laser ellipsometry: The multiple angle manual goniometer with superior performance and angle accuracy of this laser ellipsometer allows measuring refractive index, extinction coefficient, and film thickness of single films and layer stacks.

High speed: The measurement speed of our laser ellipsometer SE 400adv enables the users to monitor single film growth and endpoint detection or to map samples for homogeneity.

The laser ellipsometer SE 400adv can be utilized to characterize single films and substrates from selectable, application specific angles of incidence. The auto-collimating telescope ensures precise measurement on most kinds of absorbing or transparent substrate with a flat, reflective surface. The fully integrated support of multiple angle measurements (40 ° – 90 ° in steps of 5 °) can be used for determining thickness, refractive index, and extinction coefficient of layer stacks. Multiple angle measurements are also applied for absolute thickness measurement to compensate the ambiguity of thickness measurement in laser ellipsometry.

The SE 400adv is the SENTECH laser ellipsometer for thickness measurement of ultra thin single films. The compact table top instrument comprises the ellipsometer optics, goniometer, sample platform, auto-collimation telescope, HeNe laser source, and detection unit. The options of our laser ellipsometer SE 400adv support applications in microelectronic, photovoltaic, data storage, display technology, life science, metal processing, and others.

SE 500adv | Combined Ellipsometry Reflectometry CER

Combined Ellipsometry Reflectometry CER SE 500adv

Unambiguous thickness determination: The combination of ellipsometry and reflectometry allows for fast and unambiguous determination of the thickness of transparent films by automatic identification of the cyclic thickness period.

Largest measurement range: The combination of laser ellipsometer and reflectometry extends the thickness range for transparent films up to 25 µm and more depending on photometer option.

Push the limits of laser ellipsometry: The multiple angle manual goniometer with superior performance and angle accuracy allows measuring refractive index, extinction coefficient, and film thickness of single films and layer stacks.

The SE 500adv combines ellipsometry and reflectometry to eliminate the ambiguity of measuring layer thickness of transparent films. It extends the measureable thickness to 25 µm. Therefore the SE 500adv extends the capability of the standard laser ellipsometer SE 400adv especially for analyzing thicker films of dielectrics, organic materials, photoresists, silicon, and polysilicon.

The SE 500adv can be operated as laser ellipsometer, as film thickness probe, and as CER ellipsometer. Consequently, it offers maximum flexibility never reached by standard laser ellipsometers. Operated as ellipsometer, single and multiple angle measurements can be performed. When operated as film thickness probe, the thickness of a transparent or weakly absorbing film is measured under normal incidence.

The combination of ellipsometry and reflectometry in the SE 500adv comprises the ellipsometer optics, goniometer, combined reflection measurement head and auto-collimating telescope, sample platform, HeNe laser source, laser light detection unit, and photometer.

The options of the SE 500adv support applications in microelectronics, microsystems technology, display technology, photovoltaics, chemistry, and others.

Spectroscopic Reflectometry


RM 1000 and RM 2000 | Spectroscopic reflectometry

Spectroscopic reflectometers RM 1000 and RM 2000

Push the limits for refractive index measurements: Our reflectometers feature most accurate single beam reflectance measurements by height and tilt adjustment of sample and high light conductance of optical layout allow repeatable measurements of n and k, measurements on rough surfaces as well as thickness measurements of very thin films.

UV to NIR spectral range:

  • RM 1000: 430 nm – 930 nm
  • RM 2000: 200 nm – 930 nm

High resolution mapping: The reflectometers RM 1000 and RM 2000 can optionally be equipped with an x‑y mapping stage and mapping software, objective lens for small spot size, and a video camera.

The spectroscopic reflectometers RM 1000 and RM 2000 measure reflectance of flat or curved samples with smooth or rough surface. Thickness, extinction coefficient, and refractive index of single films or layer stacks are calculated using SENTECH FTPadv Expert software. Single films between 5 nm and 50 µm thickness, layer stacks, and substrates can be analyzed in the UV‑VIS‑NIR spectral range.

The RM 1000 and RM 2000 represent high end SENTECH reflectometers. The table top device comprises the highly stabilized light source, the reflection optics with auto-collimating telescope and microscope, the height and tilt adjustable sample platform, the spectral photometer, and the power supply. It can be optionally equipped with an x‑y mapping stage and mapping software, objective lens for a second spot size, and a video camera.

Besides film thickness and optical constants, the composition of films (e. g. of AlGaN on GaN, SiGe on Si), AR coating (e. g. on textured silicon solar cells, UV sensitive GaN devices), and coatings on small medical stents can be measured by our reflectometers. These reflectometers support applications in microelectronics, microsystems technology, optoelectronics, glass coatings, flat panel technology, life science, biotechnology, and others.

The comprehensive, recipe oriented FTPadv EXPERT software for our reflectometers RM 1000 / 2000 includes measurement set-up, data acquisition, modeling, fitting, and reporting. An extensive database of predefined customer proven and ready to use applications is already built in. The AutoModel option allows for automatic selection of sample model from a spectra library. Based on SENTECH expertise in spectroscopic ellipsometry, a large materials library and the variety of dispersion models allow the analysis of nearly all materials and films by our spectroscopic reflectometers. The data library can easily be updated with new optical data by the operator. SENTECH supports its customers with the measurement of new materials with unknown optical properties by spectroscopic ellipsometry.

FTPadv | Film Thickness Probe Table Top Reflectometer

Film Thickness Probe Table Top Reflectometer FTPadv

Shortest way to film thickness: By selecting and starting an appropriate recipe, the FTPadv reflectometer gives thickness measurement in less than 100 ms with precision of less than 0.3 nm and in a thickness range of 50 nm – 25 µm.

Unique AutoModel feature: Operator errors are reduced to a minimum by the comparison between the measured reflection spectrum and the spectra library.

SE-based material library: A large material library based on SENTECH most accurate spectroscopic ellipsometry measurement supplies recipes for the measurements of optical constants of new materials.

Best application expertise: For 20 years, SENTECH has successfully sold the Film Thickness Probe FTPadv for various applications. This table top reflectometer features thickness measurement of small samples up to large window panes, insitu or inline, at low or high temperatures, in industrial or research environments, by remote or direct control.

The tabletop reflectometer FTPadv accurately and reproducibly probes thickness and refractive index of transparent and weakly absorbing films on reflective and transparent substrates. The FTPadv can be attached to a microscope or be equipped with a stabilized light source for thickness measurement of layers up to a thickness of 25 µm (thicker on request). The extensive database of predefined, customer proven, and ready to use applications benefits from SENTECH spectroscopic ellipsometer experience.

The FTPadv features the thickness measurement of any layer from a multilayer sample making the FTPadv the ideal cost-effective solution for film thickness measurement. The FTPadv for process control comprises an optical fiber bundle with post and sample holder, a stabilized light source with halogen lamp, and the FTP optics and controller station. LAN connection to PC allows remote control of the FTPadv in industrial applications like harsh environment, special protected rooms or large machinery.

The reflectometer FTPadv comes with a huge number of predefined recipes, such as dielectrics on semiconductors, semiconductors on semiconductors, polymers on silicon, films on transparent substrats, films on metallic substrates, and others. The unique AutoModel feature allows the detection of sample types by fast comparison with spectra library. This reflectometer reduces operator errors to a minimum. Film thickness measurement by optical reflection have never been so easy.

SENTECH FTPadv menu driven operation software permits thickness measurement of single and multiple layer structures with excellent operator guidance. Furthermore, it features powerful analyzing tools and outstanding reporting functionality. Additional mapping software is available to control a motorized sample stage. Upgrading the software to the software package FTPadv EXPERT for advanced analysis of reflection measurements extends the standard software package by the application of materials with unknown or not constant optical properties. So thickness measurement and the analyze of refractive index and extinction coefficient of single films is possible.