Self‐Induced Nucleation Growth of GaN Columns by Chemical Vapor Deposition

• Published in: Physica status solidi. A, Applications and materials science Applications and materials science, 2018-04, Vol.215 (7), p.n/a
• Main Authors: Ramírez‐González, Francisco S., García‐Salgado, Godofredo, Morales, Crisóforo, Díaz, Tomás, Rosendo, Enrique, Nieto‐Caballero, Fabiola G., Luna, José A., Coyopol, Antonio, Romano, Román, Galeazzi, Reina, Martínez, Hugo
• Format: Article
• Language: English
• Subjects: Ammonia; Chemical vapor deposition; Columns (structural); CVD; Gallium arsenide; GaN structures; Metal particles; nitridation; Nucleation; self‐induced nucleation; Substrates; Wurtzite
• ISSN: 1862-6300; 1862-6319
• DOI: 10.1002/pssa.201700791

GaN columns are grown by (1 1 1) GaAs nitridation at 1000 °C. GaAs wafers are used as a substrate and Ga source. The nitridation is performed using a hydrogen and ammonia flow mix into a horizontal chemical vapor deposition (CVD) system at atmospheric pressure. XRD in correlation with pole figure shows that the structure is wurtzite with a (0 0 0 2) preferential plane. The SEM images show the growth of GaN columns with an agglomerate formation on top. EDS results show that the agglomerate is Ga rich, suggesting a self‐induced nucleation growth. The growth mechanism is discussed briefly. The average diameter and length of the columns are around 1.2 and 10 µm, respectively. The method reported here do not use a template or foreign metallic particles catalyst. In this work, GaN columns obtained by Chemical Vapor Deposition (CVD) are presented. In the experiments, the only Ga source is the substrate. The experiments are carried out at atmospheric pressure at 1000 °C. The presence of Ga at the columns tip suggest a self‐induced nucleation growth.