We have studied deposition of hydrogenated Si cluster ions, Si
nH
x+ grown in an External Quadrupole Static attraction Ion Trap (EQSIT), on Si surfaces. The Si
6H
13+ and Si
8H
19+ ions, which have
sp3 bonding networks, were grown stably in the EQSIT and subsequently deposited on the Si(111)-(7×7) surfaces with impact energy
Ed = 6 and 12 ± 1 eV. The surface structures with the clusters were observed by Scanning Tunneling Microscopy (STM) and investigated in comparsion with the Si
6H
13+ and Si
8H
19+ structures calculated using the density functional theory. The STM observations indicated that the cluster ions adsorbed preferentially on the faulted half of the Si(111)-(7×7) unit cell. We observed that Si
6H
13+ is more resistant to fragmentation than Si
8H
19+ on impact to the surfaces. We consider that the difference is due to the structural difference of the clusters; Si
6H
13+ ions have a tightly connected ring structure while Si
8H
19+ ions have chain structures with several isomers.
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