Research Initiation Award: Heteroepitaxial Layered Structures of Aluminum Nitride and Beta Silicon Carbide (REU Supplement)

采用异质外延化学气相沉积技术制备了碳化硅上氮化铝和碳化硅上氮化铝的薄层结构。β型碳化硅最初是通过将硅衬底表面转化为碳化硅，并通过硅烷和乙烯的化学气相沉积来生产的。采用金属有机化学气相沉积法生产外延化氮化铝。通过退火研究和热力学模型对这些结构的稳定性进行了评估。所生产的材料用x射线衍射、卢瑟福后向散射光谱、扫描电子显微镜和二次离子质谱进行表征。在碳化硅上的外延氮化铝层可以降低晶体缺陷密度，而在氮化铝上的外延碳化硅层应该与衬底电隔离。这项研究将改善这些半导体的结构和电气质量，增加它们在电子和光电子器件中的应用潜力。

Thin-layered structures of both aluminum nitride on silicon carbide and silicon carbide on aluminum nitride are developed by heteroepitaxial chemical vapor deposition. Silicon carbide in the beta form is produced initially by converting the surface of a silicon substrate to silicon carbide, and by chemical vapor deposition with silane and ethene. Epitaxial aluminum nitride is produced by metalorganic chemical vapor deposition. The stabilities of these structures are evaluated with annealling studies and thermodynamic modelling. Materials produced are characterized with X-ray diffraction, Rutherford backscattering spectrometry, scanning electron microscopy, and secondary-ion mass spectroscopy. A reduction in the crystal defect density in expected for epitaxial aluminum nitride layers on silicon carbide, while epitaxial silicon carbide layers on aluminum nitride should be electrically isolated from the substrate. This research will result in improved structural and electrical quality of these semiconductors, increasing their potential for applications in electronic and optoelectronic devices.