Scanning a variety of precision optical and metrology equipment to find the flattest and smoothest material CONSIDER SUBSCRIBING 🥰 ☕Buy me a coffee? https://www.buymeacoffee.com/Breakingtaps 🔬Or Patreon if that's your jam: https://www.patreon.com/breakingtaps 📢Twitter: https://twitter.com/BreakingTaps 💻Discord: https://discord.gg/R45uCXcEv4 In the very first AFM video, I showed a "precision" gage block and everyone was surprised how rough it looked. So today we are scanning a variety of surfaces (gage block, mirrors, silicon, mica) to see how they compare in flattness and roughness. The flattest surface is considered "atomically flat", meaning the surface is a single, continuous layer of atoms in the crystal all at the same height. Wild! I mention in the video, but it should be noted that flatness and smoothness/roughness are not quite the same. Flatness is a global property of how planar the surface is, while smoothness/roughness is a measure of smaller deviations from the average or median surface. I freely interchange the terms, partially on accident, but also because at the scan size it becomes a bit meaningless. At 10 microns flat and smooth are pretty similar concepts. ==== References ==== - Ostendorf, F., Schmitz, C., Hirth, S., Kühnle, A., Kolodziej, J. J., & Reichling, M. (2008). How flat is an air-cleaved mica surface? Nanotechnology, 19(30), 305705. doi:10.1088/0957-4484/19/30/305705  ==== Equipment and techniques ==== - nGauge AFM from ICSPI: https://www.icspicorp.com/ - Scans are post processed in Gwyddion (http://gwyddion.net/) and 3D images rendered in Blender - Mica is from Ted Pella ==== Timeline ==== 0:00 Intro 0:51 #6 - Gage Block 1:18 #5 - First surface mirror 1:52 #4 - λ/20 quartz mirror blank 3:05 #3 - Glass slide 4:13 Interlude - Flat vs Smooth/Rough 5:22 #2 - Silicon Wafer 6:41 #1 - Mica 9:03 Scan compilation comparison 9:39 Uses for mica