Structural properties and surface roughness of heterostructure GaN/AlN on Si (100) substrate

The GaN is considered by many as it has demonstrated the capability to be the displacement technology for silicon semiconductor in power electronic devices and light emitting diodes. In this project, heterostructure of GaN/AlN were deposited using RF magnetron sputtering at room temperature and its properties was studied. The structural and surface roughness of the deposited films were studied using X-ray diffraction (XRD) and atomic force microscope (AFM). Additionally, cross-sectional of field emission scanning electron microscope (FESEM) was used for the measurement of GaN/AlN thickness. The XRD results show that the deposited GaN is amorphous while the surface roughness and grain size are in the of $\sim 2$ nm and 60 nm, respectively. The surface topography observed using AFM shows that the GaN/AlN has homogenous structure while FESEM images show that the GaN/AlN film has pebble like structure.