Large positive VFB shift achieved by a band alignment modulated with insertion of Ga2O3 dipole layer
Abstract
In this Letter, a Ga2O3 dipole layer deposited at the SiO2/HfO2 interface by in situ atomic layer deposition (ALD) has been demonstrated to be a great positive dipole. Through the in situ ALD of 10–30 cycles Ga2O3 dipole layer, a 1.09–1.59 V flatband voltage positive modulation range is obtained with a small 0.05–0.36 nm equivalent oxide thickness penalty, respectively. The modification of the band alignment is verified by x-ray photoelectron spectroscopy measurement on the gate stacks before and after Ga2O3 dipole layer insertion. The valence band offset between SiO2/HfO2 has been suppressed by the insertion of Ga2O3, proving a p-type dipole nature of Ga2O3 dipole layer. The first interface of SiO2/Ga2O3 more dominantly decides the p-type nature, and the second Ga2O3/HfO2 suppresses it. This work indicates that ALD of Ga2O3 is a promising positive dipole candidate for multiple threshold voltage technology in advanced process nodes.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (9)
Xiao-na Zhu
Lei Shen
Key Laboratory of Functional Polymer Materials of Ministry of Education; Tianjin Key Laboratory of Functional Polymer Materials; Institute of Polymer Chemistry, College of Chemistry
Yu-Chun Li
Yu-Dong Lv
State Key Laboratory of ASIC and System, Shanghai Institute of Intelligent Electronics & Systems, School of Microelectronics, Fudan University 1 , Shanghai 200433,
Cai-Yu Shi
School of Microelectronics, College of Integrated Circuits and Micro-Nano Electronics, Fudan University 1 , Shanghai 200433, ; , Shanghai 201203, ; , Jiaxing, Zhejiang Province 314100,
Teng Huang
Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences
Zi-Ying Huang
School of Microelectronics, College of Integrated Circuits and Micro-Nano Electronics, Fudan University 1 , Shanghai 200433, ; , Shanghai 201203, ; , Jiaxing, Zhejiang Province 314100,
David Wei Zhang
Hong-Liang Lu
School of Microelectronics, College of Integrated Circuits and Micro-Nano Electronics, Fudan University 1 , Shanghai 200433, ; , Shanghai 201203, ; , Jiaxing, Zhejiang Province 314100,