Surface and Interface Studies of Si-rich 4H-SiC and SiO2
2005 (English)In: Materials Science Forum Vols. 483-485, Trans Tech Publications Inc., 2005, 581-584 p.Conference paper (Other academic)
A photoemission study of Si-rich polar and nonpolar 4H-SiC surfaces before andafter initial oxidation are presented. Core level and valence band data recorded usingsynchrotron radiation are utilized to explore the properties of these surfaces and of theinterfaces.The Si-rich surfaces showed three prominent surface Si 2p components. These componentsare strongly attenuated upon oxygen exposures and can not be detected after an exposure of3000 L. After exposures of ≥200 L the number of oxidation states, i.e. Si+1, Si+2 and Si+4oxidation states, and also their shifts are found to be the same as after initial oxidation of thesame surfaces prepared by in situ heating.Only one sharp C 1s core level is observed on the Si-rich surfaces. This is quite differentcompared to earlier findings on the same surfaces prepared by in situ heating whereprominent surface shifted C 1s components are found. After oxygen exposure of ~ 200 L theC 1s peak is broadened and an asymmetry is observed on the high binding energy side. Thistogether with the Si 2p results show that oxygen exposures of ~200 L affect not only the Sioverlayers. Layers in the SiC substrate are also affected since the C 1s peak is broadened andthe Si 2p spectrum show the same oxidation states as after large exposures and after oxidationof these surfaces prepared without Si overlayers.
Place, publisher, year, edition, pages
Trans Tech Publications Inc., 2005. 581-584 p.
Silicon Carbide, Oxidation, Angle resolved photoemission
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-78529DOI: 10.4028/www.scientific.net/MSF.483-485.581OAI: oai:DiVA.org:liu-78529DiVA: diva2:533872