Ellipsometry of thicker SiO2 film over bulk Si substrate

In summary: Expert SummarizerIn summary, Faisal is struggling to fit experimental data with models when using JWoollam Ellipsometer and WVASE 32 software to measure a wafer with a Silicon substrate and 8 um SiO2 film. The MSE is high, but literature examples have shown success with a much thicker SiO2 film. Suggestions for improving results include ensuring the correct model is being used, proper calibration and measurement parameters, and seeking guidance from other researchers or the manufacturer.
  • #1
Faisal Ahmed
1
0
Dear All,
I hope you are good.

But I am stuck in a measurement. I use JWoollam Ellipsometer and WVASE 32 software to perform ellipsometric measurements of a wafer which contains Silicon as substrate and SiO2 8 um as film over it. I performed a number of measurements on different points of the wafer but I could not fit the experimental data with models and the MSE is too high.

However, in literature examples of SiO2 film as thick as 500 nm over Silicon substrate are available.

If you can guide me, I shall be thankful.

Faisal
 
Physics news on Phys.org
  • #2


Dear Faisal,

Thank you for reaching out for assistance with your ellipsometric measurements. It sounds like you are having trouble fitting your experimental data with models and are experiencing a high mean squared error (MSE). This can be a common issue when performing ellipsometry, but there are a few things you can try to improve your results.

First, make sure you are using the correct model for your system. It is possible that the literature examples you have found are using a different model than the one you are using. You may need to adjust your model parameters or try a different model altogether.

Additionally, it is important to ensure that your experimental setup is properly calibrated and all measurement parameters are set correctly. Small errors in calibration or measurement settings can greatly affect the accuracy of your results.

If you are still having trouble fitting your data, it may be helpful to consult with other researchers in your field or reach out to the manufacturer of your ellipsometer for further guidance. They may have specific tips or troubleshooting steps for your particular instrument.

I hope this helps and wish you success in your measurements.
 

1. What is ellipsometry and how does it work?

Ellipsometry is an optical technique used to measure the thickness and optical properties of thin films on substrates. It works by measuring the change in polarization of light as it reflects off the sample at different angles.

2. Why is ellipsometry useful for measuring thicker SiO2 films over bulk Si substrates?

Ellipsometry is particularly useful for measuring thicker SiO2 films over bulk Si substrates because it is a non-destructive technique and can provide accurate measurements even for thicker films. It also has a high sensitivity and can detect subtle changes in film thickness or optical properties.

3. What are the main parameters measured in ellipsometry for thicker SiO2 films over bulk Si substrates?

The main parameters measured in ellipsometry for thicker SiO2 films over bulk Si substrates are the film thickness, refractive index, and extinction coefficient. These parameters can provide important information about the film's composition, structure, and optical properties.

4. How is the data from ellipsometry analysis used to determine the thickness and optical properties of thicker SiO2 films over bulk Si substrates?

The data from ellipsometry analysis is used to fit a mathematical model to the measured changes in polarization. This model takes into account the film thickness, refractive index, and extinction coefficient, and can accurately determine these parameters for thicker SiO2 films over bulk Si substrates.

5. What are the advantages and limitations of using ellipsometry for thicker SiO2 films over bulk Si substrates?

The advantages of using ellipsometry for thicker SiO2 films over bulk Si substrates include its non-destructive nature, high sensitivity, and ability to provide accurate measurements. However, one limitation is that ellipsometry may not be suitable for measuring very rough or non-uniform films, as the mathematical model relies on the assumption of a smooth, uniform film.

Hot Threads

Recent Insights

Back
Top