Improvement of the Anneal-Induced Valence Band Offset Variation by the Hybrid Deposition of ${\rm HfO}_{2}$ on Si
- Resource Type
- Authors
- Hongxia Liu; Yue Hao; Fei Ma; Ji-Bin Fan
- Source
- IEEE Transactions on Electron Devices. 60:1536-1539
- Subject
- Materials science
Fabrication
Annealing (metallurgy)
Analytical chemistry
chemistry.chemical_element
Oxygen
Electronic, Optical and Magnetic Materials
Threshold voltage
Dipole
X-ray photoelectron spectroscopy
chemistry
Thermal stability
Electrical and Electronic Engineering
Spectroscopy
- Language
- ISSN
- 1557-9646
0018-9383
Controlling threshold voltage variation during fabrication is essential, and one source for the variation is the thermal instability of valence band offset (VBO) for HfO2 deposited on Si. It has been reported that VBO can be changed as much as 0.33-0.60 eV after annealing. This paper proposes a hybrid process with both H2O and ozone as oxygen source during the deposition of HfO2 film. X-ray photoelectron spectroscopy shows that the VBO of this hybrid-fabricated film changes as little as 0.02 eV after a 600 °C anneal, which is compatible with the gate-last process. The improved stability is further confirmed by the VFB extracted from the C-V measurement. The physical processes that may be responsible for this improvement are discussed.