Investigation of the GaN thin films by ESR spectroscopy

In this thesis; it is aimed to characterize GaN sample which has been widely used nowadays, especially in electronics sector. GaN epitaxial structures have been produced with different contents of carbon dopants by applying different production conditions and it is known that the electrical performance of the samples increase by the increasing amount of carbon dopant. In this thesis, for the purpose of examining the magnetic, structural, optical properties of GaN which have different doped carbon contents; XRD, ESR, PL, SIMS and AFM studies have been held. The relation with the obtained experimental findings; the amount of carbon found in the grown GaN samples have been evaluated. In addition, the fabrication production procedures have been investigated on the fabricated transistors which were based on GaN samples containing three different amounts of carbon dopants. By XRD findings, information on carbon doped into GaN has been obtained. ESR findings have given information about the damage centers found in GaN epitaxial structures. ESR signal intensities have increased by increasing power values of etching process and decreased by increasing duration of annealing process. PL results have indicated an emission band at 2.2 eV for the carbon-doped GaN. AFM results have shown that the surface roughness of the samples have been increased by increasing amount of carbon dopants. SIMS results have given quantitative information about the doped content of carbon in GaN.