Patent ID: 9645125
Date: 2017-05-09
CPC Classifications: G01N

Claim:
1. A method of measuring an atmosphere in a guest vacuum chamber of a vacuum tool, the method comprising: pumping down a host vacuum chamber to a selected base vacuum pressure; measuring a first composition of an atmosphere in a host vacuum chamber of the vacuum tool using a residual gas analyzer (RGA) at the selected base vacuum pressure, wherein the host and guest vacuum chambers are not coupled during the measuring of the first composition; coupling the host vacuum chamber to the guest vacuum chamber, so that the atmosphere in the host vacuum chamber mixes with the atmosphere in the guest vacuum chamber to form a mixed atmosphere in the host vacuum chamber; measuring a second composition of the mixed atmosphere in the host vacuum chamber using the RGA after the chambers are coupled; and using a processor, automatically determining a composition of the atmosphere in the guest vacuum chamber using the measured first and second compositions.