Patent ID: 8142567

Claim:
A vacuum processing apparatus having a vacuum processing chamber, a gas supply unit for supplying processing gas to the vacuum processing chamber, and a turbo-molecular pump for reducing pressure of the vacuum processing chamber, wherein the vacuum processing apparatus comprising a particle dispersion prevention unit disposed between the turbo-molecular pump and the vacuum processing chamber, wherein the particle dispersion prevention unit includes a blade support ring, a plurality of blades provided on an outer circumference of the blade support ring, and an annular space formed downstream of the plural blades, wherein a tilting direction of the blade of the particle dispersion prevention unit is opposite a tilting direction of a rotary blade of the turbo-molecular pump, and a gap between the blades forms a first exhaust route, wherein the blade support ring includes a hole formed in a center, which forms a second exhaust route as a gas passage, and wherein the annular space transfers the gas passing through the second exhaust route in a radial direction so as to be mixed with the gas passing through the first exhaust route to form a third exhaust route for guiding the mixed gas to the rotary blade of the turbo-molecular pump.