Abstract: A process for detachment and removal of microscopic contaminant particles from a surface includes a pulsed detach light directed at the surface to excite a contaminant particle thereon at or near its resonant frequency, to thereby detach the particle from the surface; and a photophoresis light directed at the particle to move it by photophoresis, to thereby prevent its reattachment to the surface. A thermal gradient may also be applied to control the velocity and direction of particle movement by thermophoresis. Detach light is of variable pulse frequency and angle of incidence.