AVS 49th International Symposium
    Electronic Materials and Devices Wednesday Sessions
       Session EL+SC-WeP

Paper EL+SC-WeP1
Mechanistic Aspects of SiC Oxidation

Wednesday, November 6, 2002, 11:00 am, Room Exhibit Hall B2

Session: Poster Session
Presenter: F.C. Stedile, UFRGS, Brazil
Authors: C. Radtke, UFRGS, Brazil
F.C. Stedile, UFRGS, Brazil
I.J.R. Baumvol, UFRGS, Brazil
I.C. Vickridge, Universite de Paris 6 et 7, France
I. Trimaille, Universite de Paris 6 et 7, France
J.-J. Ganem, Universite de Paris 6 et 7, France
S. Rigo, Universite de Paris 6 et 7, France
Correspondent: Click to Email
SiC is the material of choice in the field of high band-gap semiconductors used in high-power, high-frequency, high-voltage, and/or high temperature applications. The possibility of obtaining an oxide film with good electrical characteristics (SiO@sub 2@) by thermal oxidation is one of its major advantages. In order to develop an oxidation model, the knowledge of the oxidation mechanism is of great importance. We investigated the incorporation of oxygen in surface and interface regions during different stages of the oxidation process of the C-face of 6H-SiC(0001) wafers as well as its dependence with the gas pressure. Oxidations in natural ultra dry O@sub 2@ followed by oxidations using isotopically enriched oxygen (@super 18@O@sub 2@) were performed. Different times of oxidation in the natural gas and chemical etching of grown oxides were used to obtain samples representing different starting conditions. Amounts of incorporated @super 18@O and depth profiles were determined using nuclear reactions in plateau and resonance regions of their cross-section curves, respectively. The results evidence that in the whole range of oxidation times studied, the oxidation process was limited by the reaction rate of diffusing oxygen with SiC. These results present a new dynamical mechanism with remarkable differences from the oxidation of Si.