Some places would mix it with nitric acid so the yellow stain would tell you that you had been exposed.
Other fun chemicals used in fabs were Silane (CSi4), methane w/ silicon instead of hydrogen, used to form a silicon dioxide layer for etching* w/ HF and final step of protection. It would spontaneously combust on contact with air, so when you popped a tank fitting it would leave a white powder residue. Silicon dioxide is used as a food additive so AFAIK that wasn't dangerous.
Phosgene was also used as a dopant. If the alarm for that went off you really got out ASAP.
Arsine was a dopant also.
This is what I sort of remember from working on slacker job in silicon fab a long time ago when the number of transistors per chip was 1. I did say a long time ago.
* You could also just oxidize the outer layer of the silicon wafer itself w/ water vaper at high temps.
Silane is like Methane, but with Silicon instead of Carbon (SiH4). Thanks god for doping was used Phosphine (PH3) and not Phosgene (COCl2), both are nasty, but the second is more. Plus I don't know how much is used, since nowadays doping is typically done by ion implantation rather than gas diffusion
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Some places would mix it with nitric acid so the yellow stain would tell you that you had been exposed.
Other fun chemicals used in fabs were Silane (CSi4), methane w/ silicon instead of hydrogen, used to form a silicon dioxide layer for etching* w/ HF and final step of protection. It would spontaneously combust on contact with air, so when you popped a tank fitting it would leave a white powder residue. Silicon dioxide is used as a food additive so AFAIK that wasn't dangerous.
Phosgene was also used as a dopant. If the alarm for that went off you really got out ASAP.
Arsine was a dopant also.
This is what I sort of remember from working on slacker job in silicon fab a long time ago when the number of transistors per chip was 1. I did say a long time ago.
* You could also just oxidize the outer layer of the silicon wafer itself w/ water vaper at high temps.
Silane is like Methane, but with Silicon instead of Carbon (SiH4). Thanks god for doping was used Phosphine (PH3) and not Phosgene (COCl2), both are nasty, but the second is more. Plus I don't know how much is used, since nowadays doping is typically done by ion implantation rather than gas diffusion
Not enough caffeine. And yeah, it would have been phosphine since it was phosphorous that was the dopant.