REGULATOR FOR GAS CONCENTRATION RATIO

摘要

The method for storing and regulating the composition ratio of gas to the desired value is disclosed. The composition ratio can be controlled very exactly by preventing the mixing of alien gas. The gas concentration regulator includes first and second MFCs for first and second gases flow control; a gas mixer for mixing gas through the first and the second MFCs; a mixed gas tank connected to an entrance of second MFC, and an inlet of the gas mixer; a vacuum pump connected with the gas mixer; and a pressure gauge for measuring the pressure in the mixed gas tank.