Patent ID: 6578369
Filing Date: 2003-06-17
Classification: B05B,B08B,B24C,H01L

Abstract:
An apparatus for cryogenically treating a surface of a workpiece, said apparatus comprising:(a) a treatment chamber in which the workpiece is positioned for a cryogenic treatment, wherein the treatment chamber is at a first, relatively low pressure; (b) a nozzle comprising a plurality of nozzle orifices distributed along a length of the nozzle in a manner effective to aim at an angle of impingement toward the workpiece surface, wherein each nozzle orifice comprises a nozzle inlet having a diameter through which a process fluid enters the nozzle orifice and an outlet through which the process fluid is cryogenically discharged from the nozzle orifice toward the workpiece surface, wherein the nozzle is at a second, relatively high pressure such that the difference between the first and second pressures causes the formation of liquid droplets that arc atomized and frozen as the process fluid passes through the nozzle orifices, wherein each of at least two of the nozzle orifices (i) comprises a divergent section and (ii) has a longitudinal distance between the inlet and the outlet that is from about 1 to about 20 times the diameter of the nozzle inlet.