You can get Hydrofluoric acid at the grocery store... it's used in "Wink" stain remover. It's strong enough to get the job done, but dilute enough to be... well, in the grocery store.
The stuff that you don't want to mess with is Silane, which Sam describes as "a toxic and explosive gas".[1]
The stuff that you don't want to mess with is Silane, which Sam describes as "a toxic and explosive gas".[1]
[1] http://sam.zeloof.xyz/second-ic/