Device for doping, deposition or oxidation of semiconductor material at low pressure

Device for doping, deposition or oxidation of semiconductor material at low pressure in a process chamber of a process tube, comprising:

• devices arranged at a first end of the process tube for supplying and discharging process gases and for generating a negative pressure in the process tube, a collar attached to the process tube at a tube closure end opposite the first end, the collar comprising a coaxial tubular segment projecting beyond a sealing rim of the process tube and terminating in an outer rim, a stopper for closing the process chamber, said stopper being adapted to rest against the sealing rim of the process tube with a given leakage rate, and a door for vacuum tight sealing of the tube closure end, said door being applied to the outer rim of the collar with interposition of a seal, and the stopper being attached in a detachable and spring loaded manner to an inside of the door.