title: Electronic properties of single Ge/Si quantum dot grown by ion beam sputtering deposition.
abstract: The dependence of the electronic properties of a single Ge/Si quantum dot (QD) grown by the ion-beam sputtering deposition technique on growth temperature and QD diameter is investigated by conductive atomic force microscopy (CAFM). The Si-Ge intermixing effect is demonstrated to be important for the current distribution of single QDs. The current staircase induced by the Coulomb blockade effect is observed at higher growth temperatures (>700 °C) due to the formation of an additional barrier between dislocated QDs and Si substrate for the resonant tunneling of holes. According to the proposed single-hole-tunneling model, the fact that the intermixing effect is observed to increase as the incoherent QD size decreases may explain the increase in the starting voltage of the current staircase and the decrease in the current step width.
authors.affiliation: Institute of Optoelectronic Information Materials, Yunnan University, Kunming 650091, People's Republic of China. National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai 200083, People's Republic of China.
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: S Y
authors.initials: SY
authors.lastname: Ke
authors.forename: J
authors.initials: J
authors.lastname: Yang
authors.forename: W D
authors.initials: WD
authors.lastname: Hu
authors.forename: F
authors.initials: F
authors.lastname: Qiu
authors.forename: R F
authors.initials: RF
authors.lastname: Wang
authors.forename: Y
authors.initials: Y
authors.lastname: Yang