摘要
The physical and electrical properties of a Ge/GeO2/HfO2/Al gate stack are investigated.A thin interfacial GeO2 layer（- 1 nm） is formed between Ge and HfO2 by dual ozone treatments,which passivates the Ge/high-k interface.Capacitors on p-type Ge substrates show very promising capacitance-voltage（C-V） characteristics by using in situ pre-gate ozone passivation and ozone ambient annealing after high-k deposition,indicating efficient passivation of the Ge/HfO2 interface.It is shown that the mid-gap interface state density at the Ge/GeO2 interface is 6.4×10^11 cm^-2·eV^-1.In addition,the gate leakage current density of the Ge/GeO2/HfO2/Al gate stack passivated by the dual ozone treatments is reduced by about three orders of magnitude compared to that of a Ge/HfO2/Al gate stack without interface passivation.
The physical and electrical properties of a Ge/GeO2/HfO2/Al gate stack are investigated.A thin interfacial GeO2 layer（- 1 nm） is formed between Ge and HfO2 by dual ozone treatments,which passivates the Ge/high-k interface.Capacitors on p-type Ge substrates show very promising capacitance-voltage（C-V） characteristics by using in situ pre-gate ozone passivation and ozone ambient annealing after high-k deposition,indicating efficient passivation of the Ge/HfO2 interface.It is shown that the mid-gap interface state density at the Ge/GeO2 interface is 6.4×10^11 cm^-2·eV^-1.In addition,the gate leakage current density of the Ge/GeO2/HfO2/Al gate stack passivated by the dual ozone treatments is reduced by about three orders of magnitude compared to that of a Ge/HfO2/Al gate stack without interface passivation.
基金
supported by the State Key Development Program for Basic Research of China(No.2011CBA00602)
the National Natural Science Foundation of China(Nos.60876076,60976013)
