Not content with making simple transistors at home, Jeri has moved up to making integrated circuits in her homelab. In Part 1 of this process she demonstrates how to cleave wafers, remove native oxide, test the dopant type with a hot probe test and loading the furnace.
UPDATE: Part 2 of this video is now available covering how to etch active areas, spin coat silicate dopants, diffuse source/drain, and test homemade nmos transistors and diodes.
wow, Hydrofluoric acid…….
An Urban legend… I think not, once it enters your skin there is the potential for significant systemic poisoning from fluoride.
Working with any sort of acid should not be treated as a matter of fact joke, no matter how ‘weak’ it is.
if you think it is a joke/urban legend, then take a look on google images for hydrofluoric acid burns.
You’re sort of missing the point. She isn’t saying the acid isn’t dangerous at all . She is saying it isn’t as dangerous as it has been portrayed, especially in the state she has it. Which is true.
Actually I am not missing the point, and it IS as dangerous as it has been portrayed, albeit not at certain concentrations, but that is NOT the point.
I have a lot of respect for what she is doing, but not for the laboratory skills (bare arms), especially as there are continual jokes throughout the video about HF.
Where she is, you can get HF off the shelf in certain cleaning products, in China where I am, I can wander down to the local shop and get basically anything, including fuming acids, for about $2us a bottle with absolutely no security checks.
The issue is: leaders in education should at all times promote best practices and safety no matter what the setup or availability of reagents.
What is better?
1. Someone who is over cautious about a weak reagent.
2. Someone that is ‘gong ho’ whilst handling highly reactive reagents.
For good laboratory practices, you never ‘assume’ that the reagents are safe just because it is marked on the bottle that it is a particular concentration.
A little less joking about with the reagents would be better, other than that the video is an excellent source of info, and my hat goes off to her.
After looking at the MSDS for both products mentioned, the glass etching paste doesn’t contain HF; it has some unnamed inorganic fluoride, likely NaF. The rust remover does contain HF but its a very dilute solution, about 2% w/w. Animal testing (rabbit) showed this to not be corrosive to skin for exposures of 1 minute.
As a side note, you should never call acids and bases strong or weak if you really mean concentrated or dillute. Strong and weak mean something very different in the context of acids and bases.