Method and System for Torsional Optical Manipulation to Remove Particles from Semiconductor Surfaces

A system for removing particles from a semiconductor surface in a dry environment, the system comprising:

• a laser source configured to emit a coherent laser beam;
• a beam expander optically coupled to the laser source and configured to expand the coherent laser beam;
• a spatial light modulator configured to receive the expanded laser beam and to divide said expanded laser beam into a plurality of individually controllable beams, each beam being modulated in at least one of phase, intensity, or angle;
• wherein the spatial light modulator is further configured to focus each of the plurality of individually controllable beams at distinct locations on a target particle disposed on the semiconductor surface, thereby forming a corresponding plurality of optical tweezers;
• a control unit operably connected to the spatial light modulator, the control unit being configured to:
• receive feedback data indicative of at least particle position or particle adhesion characteristics;
• and
• adjust at least one of the phase, intensity, or angle of each of the plurality of beams to induce torsional forces on the target particle by alternately imparting rotational motion in clockwise and counterclockwise directions, thereby weakening adhesion forces between the target particle and the semiconductor surface;
• an AOI system configured to detect the position or presence of the target particle on the semiconductor surface and provide the feedback data to the control unit;
• and
• an airflow generation unit configured to generate a controlled airflow directed toward the semiconductor surface to remove the target particle after its adhesion is sufficiently reduced by the torsional forces.