Patent ID: 8623141

Claim:
A vacuum system for semiconductor fabrication comprising: a vacuum chamber for performing a semiconductor fabrication process; a vacuum source; a piping system fluidly connecting the vacuum chamber to the vacuum source, wherein the piping system is configured without any horizontal flow path sections of piping and includes a first piping branch and a second piping branch, wherein the first piping branch includes a first bifurcated fitting, the second piping branch includes a second bifurcated fitting and the first and second piping branches being fluidly connected to the vacuum source by a third bifurcated fitting, each of the first, second and third bifurcated fittings having two inlet sections and a combined outlet section and configured without a horizontal flow path section, wherein each of the first and second bifurcated fittings being fluidly connected to two pumping ports on the vacuum chamber and the two inlet sections of the third bifurcated fitting are each fluidly connected to one of the outlet sections of the first and second bifurcated fittings; a first throttle valve fluidly connecting the outlet section of the first bifurcated fitting to one of the inlet sections of the third bifurcated fitting; a second throttle valve fluidly connecting the outlet section of the second bifurcated fitting to one of the inlet sections of the third bifurcated fitting; and an isolation valve fluidly connecting the outlet section of the third bifurcated fitting to the vacuum source, each of the throttle valves being independently controllable and operable to adjust the pressure in each piping branch.