Study of growth, structure, optical and electrical properties of rf sputtered GaN thin films.

Gallium Nitride thin films were deposited by rf sputtering of GaAs target with nitrogen as the reactive and sputtering gas, in the substrate temperature range 400$^circ $C--700$^circ $C. Films were grown directly on quartz substrates as well as on low temperature grown GaN buffer layers. GaN films grown on quartz substrates were found to be polycrystalline and exhibited preference to either (10$bar1$0) or (0002) crystallite orientation depending on substrate temperature. In contrast, the films deposited on GaN buffer layers were found to be strongly (10$bar1$0) oriented at all substrate temperatures, with improved crystallinity. The crystallite size of the films grown on quartz substrates was found to increase from 3$pm$2,nm to 17$pm$5,nm, as the substrate temperature was increased from 400$^circ $C to 550$^circ $C. At higher substrate temperatures, the crystallite size decreased steadily to the value of 11$pm$5,nm for the film deposited at 700$^circ $C. More Info

Tags :
Your rating: None Average: 5 (1 vote)