Author/Authors :
Yan، نويسنده , , Long and Yang، نويسنده , , Haiqiang and Gao، نويسنده , , Hongjun and Xie، نويسنده , , Sishen and Pang، نويسنده , , Shijin، نويسنده ,
Abstract :
The initial stage of Ge adsorption on Si(1 1 1)-(7×7) surface has been investigated by ultrahigh-vacuum scanning tunneling microscopy at room temperature. We demonstrate that there is a critical nucleus for the adsorbed Ge clusters on Si(1 1 1)-(7×7) surface. Such clusters can behave like quantum dots, which display two states at +1.5 and −1.5 eV with respect to the Fermi level. The formation mechanism of the clusters is discussed.
