Atomic Force Microscope Model

thingiverse

Human: Here's how an atomic force microscope or scanning-tunneling microscope works to see atoms and molecules in basic terms. Slide the scaffold part of the frame and the tip will rise and fall to feel out the surface. You can change the surface with features such as steps or islands to get different results. It simplifies how AFM and STM work but still explains the main idea of how to map out a surface that's too small to see with visible light. Eventually, I want to cover the surface so my students can map out what it looks like by measuring changes in height as they "scan" the surface, and also make other surface structures that can be mapped out. Printer: Printer Settings Da Vinci Jr. Rafts: No Supports: No Infill: 5% Notes: The frame and tip files are set to print upside down. This lets them print without supports or rafts. Depending on your print bed, a little bit of glue from a glue stick applied before printing will prevent longer pieces from curling up as they cool. Standards NGSS Overview and Background This model helps us continue talking about the history of atoms after we've talked about how we used to learn about the atom's structure. Once students understand that, it's good to discuss modern technologies like AFM. It helps us see atomic surfaces in detail. Objectives: Students will be able to explain how AFM/STM makes an image of a surface with atoms. Students will know how to draw a surface profile based on data from the tip height change. Students can predict changes in surface height when they add things like islands, steps, or holes. Lesson Plan and Activity Talk about why light microscopes can't show us atoms and molecules. Explain how to move the scaffold over the surface so that the tip rises and falls as it touches it. Let the students figure out and discuss how this technique lets them create an image of an atomic surface like an AFM does. Ask the students to make graphs with the height of the tip vs position on both the x and y axes, then have them draw a surface profile based on those graphs. They can reconstruct a 3D image by drawing multiple slices together. This is basically how AFM/STM works. Materials Needed: AFM Model Graph Paper Floder or cardboard to block view of the model's surface