کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1691460 | 1011315 | 2007 | 8 صفحه PDF | دانلود رایگان |

Early stages of Cr contact formation on 6H-SiC(0001) were investigated using the atomic force microscope (AFM) and current-sensing AFM with conducting tip. Cr layers were vapor deposited under ultrahigh vacuum onto samples cut out of a single crystal of n-type 6H-SiC(0001) that were ex situ hydrogen etched in a tubular flow reactor. Topography of the samples, their local conductance patterns and local current–voltage characteristics of the Cr/SiC contact were examined simultaneously as a function of Cr-adlayer thickness and annealing temperature.The growth of Cr follows the Stranski–Krastanov growth mode. The layers of mean thickness ⩾4.5 nm have a grainy structure. Differences in quality of the electric contact between the grains and the substrate as well as between the grains themselves enable to obtain a good contrast image of the local conductance of the layer. The contact of the as-deposited at room temperature Cr-layer of the thickness from 1.5 to 10 nm is typical of the rectifying junction. Annealing the Cr-SiC contact at temperatures up to 1800 K leads to coalescence of grains and dissolution of Cr in the substrate. The dissolution essentially disturbs the rectifying character of the electric contact Cr/SiC.
Journal: Vacuum - Volume 82, Issue 4, 12 December 2007, Pages 364–371