Rf-Mbe Growth Of Iii-Nitrides Heterostructures For Light Detecting Applications

摘要

Dalam penyelidikan ini, GaN p-n struktur homo, AlN/GaN struktur hetero,uddan AlxGa1-xN/GaN struktur hetero telah berjaya ditumbuhkan di atas substrat silikonud(Si) (111) menerusi epitaksi alur molekul plasma terbantu (MBE) untuk aplikasiudpengesan foto. Galium (7N) dan aluminium (6N5) dengan ketulenan yang tinggiudtelah digunakan dalam sel Knudsen dan nitrogen (7N) berketulenan tinggi telahuddibekalkan kepada frekuensi radio (RF) 13.56 MHz untuk menjana sumber spesisudnitrogen reaktif. Nilai tekanan nitrogen dan kuasa pelepasan masing-masingudditetapkan malar pada 1.5x10-5 Torr dan 300 W sepanjang projek ini. Morfologiudpermukaan, sifat-sifat struktur dan optik daripada semua sampel telah disiasat denganudmenggunakan pantulan belauan elektron bertenaga tinggi (RHEED), mikroskopudimbasan elektron (SEM), mikroskop imbasan electron pancaran medan (FESEM),udmikroskop electron transmisi (TEM), mikroskop daya atom (AFM), belauan sinar-Xudberesolusi tinggi (XRD-HR), fotoluminesen (PL), dan spektroskopi Raman, masing-masing.ududIn this research work, GaN p-n homostructures, AlN/GaN heterostructures,udand AlxGa1-xN/Ga heterostructures were successfully grown on silicon (Si) (111)udsubstrates by plasma-assisted molecular beam epitaxy (MBE) for photodetectorudapplications. High purity gallium (7N) and aluminum (6N5) were used in theudKnudsen cells and high purity nitrogen (7N) was supplied to 13.56 MHz radioudfrequency (RF) source to generate reactive nitrogen species. The nitrogen pressureudand discharge power values were kept constant at 1.5x10-5 Torr and 300 W duringudthis project, respectively. The surface morphology, structural and optical propertiesudof all the samples were investigated by using reflection high energy electronuddiffraction (RHEED), scanning electron microscopy (SEM), field emission scanningudelectron microscopy (FESEM), transmission electron microscopy, atomic forceudmicroscopy (AFM), high-resolution X-ray diffraction (HR-XRD),udphotoluminescence (PL), and Raman spectroscopy, respectively.