News Flash: Student Memories I starting querying students on what they have remembered from their STEM classes years back! Surprising answers!
The "Art Wafer"
The first fab (cleanroom) experience our students and workshop participants are exposed to is the making of an "Art Wafer" which we also refer to as the "Tourist Wafer".
Generally, the wafer has a layer of silicon dioxide deposited in our furnace. The way this is done is to heat the wafers to about 900-1000C in with some water vapor (call "wet oxidation"). Details of this can be found in our fabrication educational modules including Deposition, Etch Overview. The Etch Overview has an activity called the Rainbow Wafer Activity which goes into more detail as to how the oxide wafers are produced.
So... once you have a layer of oxide on your silicon wafer (substrate) you can pattern through lithography and subsequently etch the wafer with a solution of Hydroflouric Accid to create a pattern in the wafer.
We have create a "Job Instruction" Guide for teaching this process to our students. It is a good tool for this sort of training, click on: Art_Wafer
For my students, I also have them design their own mask (pattern) here is a link to this assignment: Make Your Own Mask