Rainbow Thin Films
Hosted by: UT Austin NASCENT Engineering Research Center
Visit our Booth: Sunday, March 7, 2021, 12 p.m. - 4 p.m.
Recommended Grades: 3rd, 4th, 5th Grades
The Challenge: Create a clear nail polish film on black construction paper to observe thin-film interactions with light.
- Use a metallic permanent marker to write your name on the black paper.
- Put the paper in a small container full of water so that the name is facing up.
- Add clear nail polish to the water, delicately in an attempt to cover the whole surface of the water.
- When you pull out the paper, the film should evenly cover the whole surface.
- Try to make the film as uniform as possible and observe how many colors show up on the paper once it dries.
- A highly uniform film will not show many color variations.
Recommended Materials: Clear nail polish, disposable plastic container, black construction paper, metallic permanent marker, paper towels
How does this activity connect to STEM and today's Girl Day theme of Creating in Code: Computing, Cybersecurity, Robotics? Thin films are widely used in the fabrication of silicon-based computer chips. The thickness uniformity of these films impacts the quality of the chip and the incidence of defects that render these chips less efficient or completely unusable. Using nail polish to make these films we can observe:
- Changes in uniformity cause different light interactions, which give way to the rainbow pattern on the paper.
- As you extract the paper, the speed will impact how well the film sticks. If the film were to break, the “chip” would fail.
Engineers have developed highly sophisticated mechanisms to create uniform thin films reliably. However, observing light interactions remains a valid way of assessing the thickness uniformity and how well the overall surface was coated. How can we modify the experiment to ensure adequate films?
Please watch these videos to learn more about the Rainbow Thin Film experiment and to meet our STEM role models!
Meet our NASCENT STEM Role Models in the video below.
See below for a video about the experiment set up and a video of the experiment explained.
Rainbow Thin Film Experiment Set-Up
Rainbow Thin Films & Nanotechnology Explained
One of the main goals of the NASCENT Center is to create a pipeline of diverse, creative students who enter college and STEM degree programs. An important step towards achieving this goal is establishing a successful K–12 outreach program. NASCENT is accomplishing this through the following programs:
- Middle School Science Academies
- Middle School Big Ideas about Little Things (BILT) Camp
- Educational school field trips around nano-concepts
- NASCENT challenge projects integrated into the school curriculum
- NanoDays and other community outreach events