Abstract: A fault-tolerant system and a method for controlling levels of a fluid in a vessel during a fluid operation, which may include draining the fluid from the vessel or filling the fluid into the vessel, are provided. A first signal indicating the first fluid level in the vessel is sensed by a primary sensor set of the system. A second signal indicating the second fluid level in the vessel is sensed by a secondary sensor set of the system. The fluid operation can be controlled using both the first signal from the primary sensor set and the second signal from the secondary sensor. Alternatively, the fluid operation can be controlled using the second signal from the secondary sensor set if the primary sensor set fails.

Abstract: The present invention is a method and system to reduce defects in conductive surfaces during electrochemical processes. The system includes a first power supply and a second power supply. The first powers supply is configured to supply a first power between a conductive surface of a workpiece and an electrode of the system. The second power supply is configured to supply a second power between the conductive surface and the electrode when a switching unit switches from the first power from the first power supply to the second power from the second power supply in response to the conductive surface contacting the process solution.