to the subject invention a reactor system 10 includes a reaction chamber 12 having a base plate 30 a gas inlet nozzle 24 or process flange a gas outlet nozzle 22 or exhaust flange and electrical feedthroughs or conductors 20 for providing a current to directly heat one or more filaments 28 within the reaction chamber 12 as shown in fig2 a fluid inlet nozzle 18 and a fluid outlet nozzle 14 are connected to a cooling system for providing fluid to the reaction chamber 10 in addition a viewing port 16 or sight glass preferably allows visual inspection of the interior of the reaction chamber 12 and can optionally be used to obtain temperature measurements inside the reaction chamber 12 according to a preferred embodiment of the subject invention as depicted in fig1 and 2 the reactor system 10 is configured for bulk production of polysilicon the system includes the base plate 30 that may for example be a single plate or multiple opposing plates preferably configured with filament supports and an enclosure attachable to the base plate 30 so as to form a deposition chamber as used herein the term u201c enclosure u201d refers to an inside of the reaction chamber 12 where a cvd process can occur one or more silicon filaments 28 preferably are disposed within the reaction chamber 12 on filament supports not shown and an electrical current source is connectible to both ends of the filaments 28 via electrical feedthroughs 20 in the base plate 30 for supplying a current to directly heat the filaments further provided is at least one gas inlet nozzle 24 in the base plate 30 connectible to a.