STRUKTUR KRISTAL DAN MORFOLOGI FILM TIPIS GaN YANG DITUMBUHKAN DENGAN METODE HOT-WIRE

Abstract

The GaN thin films were grown on (0001) sapphire substrates using hot-wire pulsed laser de­po­sition methode. The substrate and hot-wire temperature were around 680 and 1000 ⁰C res­pec­tive­ly. The effects of the nitrogen pressure during growth on the properties of GaN films have been investigated. XRD characterization shows that GaN film with c- axis orientation of (0002) and (0004) occurs if nitrogen gas partial pressure was increased up to 0.25 mbar, but the quality of GaN film decreased if gas partial pressure increased up to 0.35 mbar. Similar result was also found for the gas partial pressure of 0.15 mbar without using heater filament at nitrogen gas flow. SEM characterization shows that at the surface of the film, there were GaN particulates of the size of 0.1–0.4 mm. Number of particulates decreased if par­tial gas pressure increased up to 0.35 mbar by using heater filament.