Abstract: An apparatus for in-situ control of the flow of a liquid precursor into a deposition chamber comprises a liquid injection system having a liquid injection outlet connected to a chamber inlet line upstream of the deposition chamber. The liquid injection system includes a liquid precursor supply, a carrier gas supply, a vaporizer, and a controller managing flows of the liquid precursor and carrier gas to the chamber. A bypass line is connected to the chamber inlet line and includes a bypass valve, a sonic orifice, and a pressure gauge upstream of the sonic orifice. To calibrate the flow of the liquid precursor, a flow of carrier gas is directed into the bypass line at a carrier gas sonic flow rate. A first steady state pressure is measured with the pressure gauge. The liquid precursor is vaporized and directed to the flow of carrier gas into the bypass line. A second steady state pressure is measured with the pressure gauge.

Abstract: An apparatus for controlling the flow of a liquid precursor into a deposition chamber comprises a liquid injection system having a liquid injection outlet connected to a chamber inlet line upstream of the deposition chamber. The liquid injection system includes a liquid precursor supply, a purge gas supply, a carrier gas supply, a liquid flow meter, and a controller managing flows of the liquid precursor and carrier gas to the chamber. A purge line is connected between the purge gas supply and the liquid flow meter and is used to trap a known mass of liquid precursor. To calibrate the flow of the liquid precursor, the purge gas is used to push the trapped liquid precursor through the liquid flow meter at a steady rate. The elapsed time for evacuating the trapped liquid precursor from the purge line is measured. Calibration information is computed using the mass of the trapped liquid precursor and the measured elapsed time based on the direct liquid measurement approach.