Effective interface passivation of a Ge/HfO_2 gate stack using ozone pre-gate treatment and ozone ambient annealing  

作　　者：赵梅 梁仁荣 王敬 许军 

机构地区：[1]Tsinghua National Laboratory for Information Science and Technology,Institute of Microelectronics,Tsinghua University

出　　处：《Journal of Semiconductors》2013年第6期181-184,共4页半导体学报（英文版）

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)

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.

关 键 词：GERMANIUM surface passivation ozone treatment interface trap density gate leakage current density 

分 类 号：TB383.1[一般工业技术—材料科学与工程]