Patent ID: 6513376
Filing Date: 2003-02-04
Classification: G01F

Abstract:
A system for indicating an amount of a process liquid contained within an interior of an ampoule, the system comprising:a first conduit in selective fluid communication with the interior of the ampoule, the first conduit having a first opening configured for disposal below an upper surface of the process liquid, the first conduit for introducing a carrier gas into the interior of the ampoule, a second conduit in selective fluid communication with the interior of the ampoule, the second conduit having a second opening configured for disposal above the upper surface of the process liquid, the second conduit for receiving the carrier gas from the interior of the ampoule, a pressure differential sensor disposed between the first conduit and the second conduit and in selective fluid communication with the first conduit and the second conduit, for sensing a pressure differential between the first conduit and the second conduit, and an indicator for indicating the amount of the process liquid in the ampoule based at least in part upon the pressure differential between the first conduit and the second conduit wherein the indication of the amount of the process liquid in the ampoule is based at least in part on: h=Î”&it;â€ƒ&it;P-CÏ Ã—g,â€ƒwhere h is a height of the process liquid in the ampoule, &Dgr;P is the pressure differential between the first conduit and the second conduit, C is a constant based at least in part on a configuration of the system, &rgr; is a density of the process liquid, and g is an acceleration due to gravity.