| 摘要 |
<p>A method of carrying out laser ablation includes applying suction at an extraction opening of a hollow working head (10), to cause reduced pressure internally of the hollow working head and to cause an airflow along an internal flow passage (26) between an exposure opening (18) and the extraction opening (19) in the head, generally tangentially past an internal beam port (24) at a reduced pressure from the exposure opening to the extraction opening. A laser beam is focussed through the beam port and the exposure opening onto a substrate proximately below the exposure opening at an incidence angle of between 10° and 50° to the normal to a surface of the substrate. The working head is traversed over the substrate in an area in which laser ablation is to be carried out.</p> |
