Fabrication And Characterization Of Gan Grown On Cubic Si (100) And Gaas (001) Substrates

Secara umumnya tesis ini membentangkan kajian lapisan GaN yang ditumbuh di atas substrat Si (100). Pada bahagian pertama tesis ini, sifat-sifat lapisan GaN di atas substrat kubik Si telah dibincangkan. Penambahbaikan ke atas sifat-sifat lapisan GaN telah dikesan melalui kaedah penyepuhlindapan. In general, this thesis presents the study of GaN layer grown on different cubic substrates. In the first part of this work, the properties of GaN film grown on (100)- oriented cubic Si substrate was investigated. Improvement in the properties of the GaN layer are observed by means of thermal annealing treatment

Effect Of Nucleation Time On GaN Layer Grown On Different Shape Of Patterned Sapphire Substrate

This work describes the effect of nucleation time on GaN layer; which was grown separately on three different shape of patterned sapphire substrate (PSS); cone PSS and dome PSS. Prior to the GaN layer growth, a low temperature of GaN nucleation layer was initially grown at 40, 80 and 160 second. The nucleation islands became larger as the nucleation time was longer. Bigger islands promote better coalescence, while smaller islands showed otherwise. Besides, the GaN layer grown on bigger islands exhibit smoother surface. From XRD measurement, FWHM of the GaN peak decreased for longer nucleation time, indicating the benefit of bigger islands to reduce the dislocations in the layer through better coalescence. It was found that the GaN layer grown on dome-patterned substrate exhibits better quality than the one on cone-patterned substrate. The growth of GaN layer on flat sapphire was also performed for comparison

Effect Of Nucleation Time On GaN Layer Grown On Different Shape Of Patterned Sapphire Substrate

This work describes the effect of nucleation time on GaN layer; which was grown separately on three different shape of patterned sapphire substrate (PSS); cone PSS and dome PSS. Prior to the GaN layer growth, a low temperature of GaN nucleation layer was initially grown at 40, 80 and 160 second. The nucleation islands became larger as the nucleation time was longer. Bigger islands promote better coalescence, while smaller islands showed otherwise. Besides, the GaN layer grown on bigger islands exhibit smoother surface. From XRD measurement, FWHM of the GaN peak decreased for longer nucleation time, indicating the benefit of bigger islands to reduce the dislocations in the layer through better coalescence. It was found that the GaN layer grown on dome-patterned substrate exhibits better quality than the one on cone-patterned substrate. The growth of GaN layer on flat sapphire was also performed for comparison