Optical coating thickness measurement using spectral reflectance instrument

Spectral Film Thickness Tester

TFT-1000 Non-contact, non-destructive film thickness measurement with one-click operation.

Get in touch Brochure

The TFT-1000 is a benchtop, non-contact thin film thickness measurement system that uses spectral reflectometry to measure film thickness, refractive index (n), reflectance, and transmittance. Configurable optical modules enable measurements from approximately 1 nm to 1800um , while delivering fast, accurate, and repeatable results with a simple one-click workflow. Designed for research, process development, and manufacturing, the TFT-1000 combines flexible hardware configurations with intuitive software to characterize a wide range of transparent and semi-transparent thin films.

KEY FEATURES

UV, Visible, and NIR Configurations

The TFT-1000 is available with four optimized spectral ranges: 300–1100 nm (Standard), 190–1100 nm (UV-Enhanced), 900–1750 nm (Near-Infrared), and 1000–2500 nm (Extended Near-Infrared). The ideal wavelength range depends on the coating material, thickness, and substrate. Custom spectral configurations are also available to meet specialized thin-film measurement applications.

Library with over 500 materials included with every system

The 500+ materials library includes oxides, nitrides, photoresists, polymers, semiconductors, hard coatings, thin metal films, solar cell stack materials (aSi, TCO, CIGS, CdS, CdTe), LCD and display films (ITO, cell gaps, polyamides), optical coatings (dielectric filters, anti-reflection, hard coatings), and OLED stacks. Dynamic measurement mode acquires spectral data continuously while the sample is in motion, enabling coating uniformity maps across large substrates.

Spot Size down to few µm

The TFT-1000 offers spot sizes from 4 µm to 2 mm, depending on the objective lens. Ultra-small spots accurately measure patterned wafers and microscopic features, while larger spots average wider areas for coating uniformity, process control, and quality assurance. Interchangeable optics maximize flexibility across research and industrial thin-film applications.

High Precision and Stability

The TFT-1000 combines next-generation light sources with high-resolution spectrometers to deliver exceptional accuracy, repeatability, and long-term stability. Designed for thin film process control, coating quality verification, and in-line deposition monitoring, it provides reliable, non-contact thickness measurements for research, production, and industrial quality assurance.

Easy to Use with Latest-Generation Analysis Software

Every TFT-1000 ships with the full analysis package: one-click measurement, real-time spectral fitting, multi-layer optical modeling, and automated reporting. Thickness, refractive index, reflectance, and transmittance are extracted from a single acquisition — no software tiers, no add-on licenses. User can run the tool with under 5 minutes of training of software.

More about

Thin film metrology for semiconductor and microelectronics manufacturing

Applications

Measure thickness, refractive index, reflectance, and transmittance of:

  • Single or multiple-layers
  • Transparent, translucent or lightly-absorbing films
  • Semiconductor — photoresist, dielectrics etc.
  • Optical Coatings
  • AR/VR devices
  • Medical – parylene, devices, catheters

How Does Spectral Reflectance Film Thickness Measurement Work?

Spectral reflectance is a fast, non-contact optical technique used to measure the thickness of transparent and semi-transparent thin films with nanometer precision. It is widely used in semiconductor manufacturing, MEMS, optics, photovoltaics, microelectronics, and advanced materials research because it provides highly accurate measurements without damaging the sample.

During the measurement, a broadband white light source is directed onto the coated surface through a precision optical probe. Part of the light reflects from the air-to-film interface, while another portion passes through the coating and reflects from the film-to-substrate interface. As these reflected beams recombine, they create constructive and destructive interference that produces a unique spectral interference pattern.

The spectrometer captures the reflected spectrum over hundreds of wavelengths in just milliseconds. Advanced optical modeling software compares the measured spectrum with theoretical models based on the optical properties of the film and substrate. The spacing and shape of the interference fringes reveal the film’s optical thickness (refractive index × physical thickness, n × d). When the refractive index is known—or simultaneously determined through curve fitting—the software accurately calculates the physical film thickness.

Unlike contact-based techniques, spectral reflectance requires no sample preparation and causes no surface damage. Measurements are completed in real time with a single click, making the technique ideal for both laboratory research and high-throughput production quality control. Modern systems can measure films from just a few nanometers to several hundred micrometers thick, depending on the material and optical properties.

With automated stage control, mapping capabilities, and powerful analysis software, spectral reflectance enables rapid thickness measurement across wafers, glass panels, optical components, and coated parts, providing manufacturers and researchers with reliable data to optimize deposition processes, improve product quality, and increase production yield.

Wavelength300–1100 nm (Standard) 190–1100 nm (UV-Enhanced) 900–1750 nm (Near-Infrared) 1000–2500 nm (Extended Near-Infrared). Custom wavelength configurations available
Precisionnm range
Material Library500+

Frequently Asked Questions

A thin film thickness tester is a non-contact optical instrument that measures coating thickness by analyzing light reflected from a coated surface. A spectral reflectance film thickness probe like the TFT-1000 extracts thickness, refractive index, reflectance, and transmittance from the interference pattern between light reflected at the film surface and at the film-substrate interface. Measurement takes seconds and requires no sample preparation.
The TFT-1000 measures film thickness from 1 nm to 1800 µm, plus refractive index, reflectance, and transmittance. It handles single layers and multi-layer stacks on transparent, translucent, and lightly absorbing films — photoresists, dielectrics, optical coatings, ITO, parylene, and solar or OLED stack materials among the 500+ in its library.
Semiconductor process engineers, optical coating manufacturers, display and AR/VR developers, solar cell producers, and medical device makers use the TFT-1000 for film thickness measurement in QC and R&D. Its non-contact operation and one-click workflow make it practical for both in-line production monitoring and laboratory analysis.
Yes. The TFT-1000 can be configured to measure multi-layer film stacks by fitting the measured reflectance spectrum to a multi-layer optical model. This is used for solar cell stacks, OLED layers, and complex optical coatings where multiple layers must be characterized simultaneously.
The minimum measurable thickness depends on the model configuration. The UV-visible model (200–1000 nm wavelength range) measures films as thin as 1 nm. The visible-range model measures from 10 nm, which is sufficient for most hard coatings, optical films, and semiconductor dielectrics. For ultra-thin gate oxides and monolayer films, the UV-visible model is appropriate.
No. The TFT-1000 is a non-contact probe that measures the as-received sample surface without cleaning, etching, or patterning. The only requirement is that the coating and substrate have sufficient optical contrast for the spectral reflectance measurement, which is the case for the vast majority of coating-substrate combinations.
The spot size depends on the objective lens used and ranges from 4 µm (high-magnification objectives) to 200 µm to 2 mm (low-magnification configurations). Smaller spot sizes are used for patterned substrates and small features; larger spots provide averaging over a wider area for uniformity measurements.
Yes. In addition to film thickness, the TFT-1000 measures refractive index, reflectance, and transmittance from the same spectral reflectance acquisition.
Measurement is real-time with one-click operation. The spectral acquisition and model fitting complete in seconds, and dynamic mode measures continuously while the sample moves.
The included library covers 500+ materials: oxides, nitrides, photoresists, polymers, semiconductors, hard coatings, thin metal films, solar stack materials (aSi, TCO, CIGS, CdS, CdTe), display films (ITO, polyamides), optical coatings, and OLED stacks.
Yes. Transparent, translucent, and lightly absorbing films are the core application of spectral reflectance film thickness measurement, on substrates from silicon to glass to polymer.

Ready to take your tribology
research to the next level?

Discover Rtec Instruments' cutting-edge solutions and see how our technology can empower your work.

Contact our experts