Comparative STM analysis of C-60 and C-70 fullerene adsorption sites on pristine and Al-modified Si(111)7 x 7 surfaces

作者：Mararov Vsevolod V; Gruznev Dimitry V; Bondarenko Leonid V; Tupchaya Alexandra Y; Zotov Andrey V^*; Saranin Alexander A

来源：Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films , 2016, 34(6): 061402.

DOI：10.1116/1.4963067

Using scanning tunneling microscopy observations, preferable adsorption sites of C-60 and C-70 fullerenes on pristine Si(111) 7 x 7 and Al-modified Si(111)alpha-7 x 7-Al surfaces at 300 and 450K were determined. The C-60 and C-70 molecules display similar, albeit not identical, adsorption behavior while the most essential variance is related with the hosting surfaces, pristine 7 x 7 or alpha-7 x 7-Al. Both C-60 and C-70 prefer to occupy positions above the Si rest atoms upon adsorption onto Si(111) 7 x 7 at 300K and change their preferable sites for those located at the Si edge adatom at 450 K, that is plausibly accompanied by releasing the Si adatom. Upon C-60 and C-70 adsorption onto Si(111) alpha-7 x 7-Al surface at 300 K, the fullerenes prefer to occupy the asymmetric sites at the dimer rows. At 450 K, the C-70 fullerenes preserve this location, while about half of the C-60 fullerenes change it for that at the corner Si adatom position. The present experimental data set serves as a useful basis for theoretical analysis.

• 出版日期2016-11