Synthesis of GaN Nanoparticles by DC Plasma Enhanced Chemical Vapor Deposition

Abstract

The unique optical properties of nanostructured GaN basically, turn it as a very important part of many electronic and optoelectronic devices such as high power transistors, UV detectors, solar cells, lasers and blue LED. The aim of the current study is GaN nanoparticle deposition at low temperature in preferred direction. In this work, GaN nanoparticles were prepared using direct current plasma enhanced chemical vapor deposition (DC-PECVD) method on Si (100) wafer as a substrate at 700°C. Gallium metal and nitrogen plasma were used as precursors. GaN nanoparticles were grown based on the direct reaction between gallium atoms and excited nitrogen species in the plasma. Structural and morphological characterizations of GaN nanoparticles were carried out using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and field emissions electron microscopy (FE-SEM). Preferred (100) direction of GaN nanostructures which obtained by careful control of processing parameters, were revealed by XRD. FE-SEM images show the average diameter of nanoparticles is 37 nm. The EDS results show the Ga to N ratio in the sample was 8.8 to 1.2 by weight which is very close to the Ga to N ratio of prefect GaN crystal. The deviance is related to the nitrogen vacancy of the sample. These results demonstrate a simple inexpensive method for GaN nanoparticle deposition at low temperature which is critical for many of applications.