Thin films are ubiquitous in modern technology, forming the functional basis of end products used in consumer electronics, high-end energy harvesting systems, and much more. Ensuring the quality of materials deposited in minuscule layers, often approaching nanoscale thicknesses (nm), is paramount in quality assurance and control (QA/QC). Although there are many quality benchmarks in thin film engineering, film thickness is one of the most critical. Additionally, issues with film thickness can also cause problems with the costs and processes associated with coating.
In our previous blog post, How is Film Thickness Measured?, we discussed the basic concepts of thin films and the principles of interference. This post will follow up with a focus on the tools used to measure film thickness.
Measuring Film Thickness
There are several tools that analysts can use to measure the thickness of films. They include contact and non-contact gauges and instruments such as microscopes and spectrophotometers. Non-contact instruments are favourable because they do not physically impinge upon the sample, meaning measurements can be conducted accurately, promptly, and non-invasively. If you are using a spectrophotometer, it is essential to note that these can only be used to measure a layer thickness of 0.3 to 60µm. Outside of those parameters, the principle of interference becomes key–a concept we have explained in our previous blog.
Optical techniques are preferred for measuring films. These include ellipsometry and reflectometry, which utilizes reflectance or transmittance to analyze the thickness values. Such techniques offer a non-destructive and non-invasive way of accurately measuring a thin film, providing data that can be used to ensure product quality and reliability.
Microspectrometry and Film Thickness
Film thickness is an important value to measure and is frequently used in many industries, including optics and semiconductors. These measurements can be taken with a microspectrophotometer, which enables a non-contact method of measuring thin film thickness in reflectance and transmittance. More about reflectance and transmittance can be found in one of our blog posts about thin film thickness.
A microspectrophotometer can be used for many other research and development laboratory applications, including measuring fluorescence and optical emissions in flat panel displays, industrial applications, and more.
A high-quality, reliable microspectrophotometer will provide so many benefits to any R&D laboratory. Not only can they be used for measuring film thickness accurately, but they can also be enhanced with additional software and technology for other applications.
CRAIC Technologies has developed a software called CRAIC FILMPRO™, which can be used with our range of CRAIC microspectrometers to measure the film thickness of thin films by using reflectance or transmittance. This software will analyze thin films on a range of substrates, including glass or silicon, and has the option to print and save reports.
One of our key products is the 2030XL PRO™ microspectrophotometer, which is used to analyze images and take film thickness measurements of large-scale samples. Specific attributes, such as absorbance, reflectance and transmission, of samples can be measured using UV-vis-NIR spectrophotometry, which enables analysts to test, identify and monitor components for a wide range of applications.
Key benefits of the 2030XL PRO™ include:
- Analyze large scale samples, such as 300mm wafers
- Automated operation
- Easy to use
- Low maintenance
- Spectral range of 200 to 2500 nm
- Suitable for color mapping
This non-contact and non-destructive analytical method is the ideal instrument for use in the semiconductor industry for the manufacture of LCD displays, OLEDs and optical products. Microspectrophotometry is used by analysts to measure film thickness to ensure it is consistant, which is crucial for developing anti-reflective coatings, protective coatings and many others.
For more information on our products and software available for measuring film thickness, contact a team member today.