MAGNETIC FLUID SEALING UNIT FOR SEMICONDUCTOR WAFER VERTICAL HEAT TREATING APPARATUS

摘要

An outer shell member (60) arranged from a lower part onto an outer circumference of a unit main body (30) is fixed on a lower end of a rotating shaft (20). A space between the rotating shaft (20) and the unit main body (30) is magnetically sealed by a magnetic fluid sealing section (40). A shaft bearing section (70) is provided at a lower end part of the unit main body (30) between the unit main body (30) and the outer shell member (60). Further, at a position closer to a reactor vessel than the magnetic fluid sealing section (40) in the vicinity of the magnetic fluid sealing section (40), a space between the rotating shaft (20) and the unit main body (30) is supplied with a purge gas.