Methods and apparatus for laser patterning leverage mask trench debris removal techniques to form etch singulation trenches. In some embodiments, the method includes forming a mask layer on the wafer, forming a pattern in the mask layer using a laser of a laser assembly where the pattern allows singulation of the wafer by deep etching and forms a trench in the mask layer with a laser beam which has a process point at a bottom of the trench, directing gas nozzles that flow a pressurized gas at the process point in the trench as the pattern is formed with a gas flow angle relative to the process point and evacuating debris from the trench using an area of negative pressure where the gas flow from gas nozzles and the area of negative pressure are in fluid contact and are confined within a cylindrical housing.