Laser Beam Orientation Control for Wafer Trim Surface Quality

The patent applies dynamics by making the longitudinal direction of the laser beam shape adjustable and changeable during processing. The controller dynamically changes the orientation of the longitudinal direction between a first orientation (intersecting the movement direction at an angle) and a second orientation (orthogonal to the movement direction) as the focusing point moves along the annular line, preventing local deterioration of the trimmed surface quality while maintaining continuous processing efficiency.

The patent changes the parameter of beam shape orientation by adjusting the longitudinal direction of the laser beam. The shaping portion modifies the laser beam shape so that the longitudinal direction can be oriented at different angles relative to the movement direction of the focusing point. This parameter change prevents the formation of a continuous modified region in certain areas, thereby suppressing local deterioration of the trimmed surface quality.

The patent transforms the static beam orientation into a dynamic one by continuously or periodically changing the longitudinal direction of the laser beam during the annular scanning process. This dynamic adjustment ensures that the beam orientation does not consistently match the movement direction, preventing the physical properties of the target material from causing surface deterioration while maintaining processing feasibility.

The patent applies preliminary anti-action by proactively adjusting the beam orientation to counteract the harmful effect of the target's physical properties. By pre-establishing an angular relationship between the beam's longitudinal direction and the movement direction, the system prevents the formation of continuous modified regions that would otherwise cause surface deterioration, rather than attempting to correct the problem after it occurs.