Patent ID: 8276648

Claim:
A method for forming a tube-based detector for signaling that a physical vapor deposition target has been reduced to a predetermined quantity of the physical vapor deposition target material, the method comprising the steps of: providing a mold member having an inner molding member and an outer molding member defining a space between the inner molding member and the outer molding member; melting a desired tube material; injecting the molten tube material into the space between the inner molding member and the outer molding member; cooling the molten tube material; removing the tube from the mold member after the molten tube material has cooled and solidified into a tube; embedding the tube in the physical vapor deposition target, wherein the tube forms an enclosure of the tube-based detector; and providing one of a filament element and a pair of electrode elements disposed within the tube, wherein if the filament element is provided within the tube, the filament element including first and second ends terminating externally of the tube, the first and second ends forming one of leads and terminals, and if a pair of electrode elements are provided with the tube, each of the pair of electrode elements including first and second ends, the second ends of the electrode elements terminating externally of the tube.