Selective growth of GaN on sapphire substrates treated with focused femtosecond laser pulses

Abstract

We developed a novel selective growth technique for metalorganic chemical vapor deposition (MOCVD) growth of GaN using an unique substrate treatment procedure; sapphire substrates were treated and patterned with focused femtosecond laser pulses. By adjusting laser-irradiation conditions, GaN film growth could be suppressed over the laser-irradiated region. Using organic layer deposition onto a sapphire substrate prior to laser irradiation, we could achieve selective growth of GaN without sapphire ablation. Compared with the conventional technique, the present selective growth procedure is characterized by patterning without the need for the etching process or mask layers.