Electron and atomic force microscopy studies of femtosecond laser machining of Si, GaAs and InP

The application of femtosecond light pulses to materials processing has recently become a topic of great interest.1 Femtosecond laser ablation dynamics has been extensively studied by techniques including time-of-flight and has also been treated theoretically [see, e.g., 2–4]. However, although numerous experimental studies have demonstrated excellent spatial control in fem tosecond laser machining, relatively few investigations have explored details of the near-surface changes in crystallographic structure and the localized changes in target composition. In this study we characterize laser-machined semiconductor samples, employing a combination of scanning (SEM) and transmission (TEM) electron microscopies as well as atomic force microscopy (AFM).