A substrate holding and rotary driving mechanism, e.g., for a cleaning chamber with vertical orientation of the wafer, that is comprised of a three-armed spider which is rotatingly installed on the outer side of the cleaning chamber and rotatingly supports on the outer ends of its arms outer shafts with eccentrically arranged inner shafts. The inner shafts pass through the outer shafts into the cleaning chamber where they support contact rollers, while the opposite ends of the inner shafts support gears driven into rotation by a synchronous belt. The contact rollers can be moved apart for insertion or removal of wafers from and into the chamber. This is achieved by turning the spider with eccentric inner shafts in one or another direction.