An apparatus for processing a substrate surface in a processchamber wherein during chemical or physical altering of thesubstrate surface a laser beam is projected inside the processingchamber and along a trajectory which does not contact the substratesurface in order to capture particles by means of the photophoreticeffect, particles which would otherwise impinge upon andcontaminate the substrate surface.
Method and apparatus for protecting a substrate surface from contamination using the photophoretic effect
Periasamy, R. (1995). IPC No. U.S. Method and apparatus for protecting a substrate surface from contamination using the photophoretic effect. (U.S. Patent No. 5472550).