Band alignment of high-k dielectric on SiO2/Si stack

Author

Jinjuan Xiang ; Xiaolei Wang ; Tingting Li ; Chao Zhao ; Wenwu Wang ; Junfeng Li ; Dapeng Chen ; Tianchun Ye

Author_Institution

Key Lab. of Microelectron. Devices & Integrated Technol., Inst. of Microelectron., Beijing, China

fYear

2012

fDate

14-15 May 2012

Firstpage

230

Lastpage

233

Abstract

Band alignments of high-k dielectrics such as atomic layer deposition (ALD) grown HfO₂ and Al₂O₃ with different thicknesses on SiO₂/Si stack are investigated by X-ray photoelectron spectroscopy (XPS). The band offsets at HfO₂/SiO₂, Al₂O₃/SiO₂ and SiO₂/Si interfaces are found to vary with physical thickness of high-k dielectric. Concepts of gap states and charge neutrality level (CNL) are employed to discuss band lineup of high-k/SiO₂/Si stack. The XPS observed results are successfully interpreted and attributed to lower CNLs of HfO₂ and Al₂O₃ related to that of SiO₂/Si stack, indicating feasibility of gap state based theory in investigating band alignment of oxide/semiconductor and oxide/oxide heterojunctions.

Keywords

MIS devices; X-ray photoelectron spectra; aluminium compounds; atomic layer deposition; hafnium compounds; high-k dielectric thin films; semiconductor-insulator boundaries; silicon compounds; Al₂O₃-SiO₂; HfO₂-SiO₂; SiO₂-Si; X-ray photoelectron spectroscopy; atomic layer deposition; band alignment; gap state; high-k dielectric; oxide-oxide heterojunction; oxide-semiconductor heterojunction; Abstracts; Hafnium compounds; High K dielectric materials; Silicon; Thermodynamics;

fLanguage

English

Publisher

ieee

Conference_Titel

Junction Technology (IWJT), 2012 12th International Workshop on

Conference_Location

Shanghai

Print_ISBN

978-1-4673-1258-5

Electronic_ISBN

978-1-4673-1256-1

Type

conf

DOI

10.1109/IWJT.2012.6212847

Filename

6212847