During doping, a foreign substance is introduced into the semiconductor crystal by diffusion during wafer production to specifically change the conductivity. There are several procedures for this. The diffusion process describes the process in which a carrier gas (nitrogen, argon) is enriched with the dopant from the gas phase and brought into contact with the wafer. Another method works with a liquid source. The carrier gas with the dopant is passed through a suitable liquid and the loaded liquid is brought into contact with the wafer.
Since the dopants are highly toxic, environmentally harmful and partly self-igniting on contact with the atmosphere, HOFER's leakage-free diaphragm compressors are typically used for this application.
|Medium: Monosilane (SiH4), Trichlorsilane (SiH3CI)|
|Discharge pressure: 25 – 200 bar|
|Power: 10 – 75 kW|