Femtosecond laser machining of gallium nitride

Ultrashort pulse laser ablation of gallium nitride (GaN) has been studied. Utilizing a 1 kHz femtosecond Ti:sapphire laser with a peak intensity of approximately 1016 W cm−2, we have successfully demonstrated controlled ablation of metal organic chemical vapour deposition and hydride vapour phase epitaxy grown GaN. Groove patterns 10–100 μm wide and as deep as 30 μm have been produced both in air and in a vacuum chamber and analyzed by scanning electron microscope and stylus profiling. This approach is demonstrated to be highly suitable for micromachining and controlled definition of features on a tens of micron length scale in materials such as GaN which are resistant to wet chemical etching.