A particles supply apparatus is equipped with cylindrical particles discharge unit provided with particles discharge outlet at lower portion thereof, and is equipped with cylindrical shutter cap covering outside circumferential surface of particles discharge unit. The local pattern is a function of the underlying wafer surface, but the global pattern is a function of the equipment in which the layer was deposited. The displacement of the sleeve relative to the stone shield is measured to determine the stroke of the brake actuator. The leading edge and trailing edge may be nonlinear shapes.