Title :
Influence of surface treatment prior to ALD high-κ dielectrics on the performance of SiGe surface-channel pMOSFETs
Author :
Wu, D. ; Lu, J. ; Radamson, H. ; Hellström, P.E. ; Zhang, S.-L. ; Östling, M. ; Vainonen-Ahlgren, E. ; Tois, E. ; Tuominen, M.
Author_Institution :
R. Inst. of Technol., IMIT, Kista, Sweden
fDate :
5/1/2004 12:00:00 AM
Abstract :
Compressively strained Si0.7Ge0.3 surface-channel pMOSFETs with atomic layer deposition (ALD) Al2O3/HfO2/Al2O3 nanolaminate and low-pressure chemical vapor deposition p+ poly-SiGe gate electrode were fabricated. Surface treatment with either hydrogen fluoride (HF) clean, or HF clean followed by water rinse was performed prior to the ALD processing. The devices with water rinse show a good control of interfacial layer and device reproducibility, while the devices without water rinse lack a clearly observable interfacial layer and show scattered electrical characteristics and distorted mobility curve. A ∼20% increase in hole mobility compared to the Si universal mobility and a ∼0.6-nm-thick continuous interfacial layer are obtained for the pMOSFETs with water rinse.
Keywords :
atomic layer deposition; chemical vapour deposition; electrodes; elemental semiconductors; hole mobility; power MOSFET; semiconductor device manufacture; surface treatment; Al2O3-HfO2-Al2O3; HF; HF clean; SiGe; atomic layer deposition; device performance; device reproducibility; gate electrode; high-κ dielectrics; hole mobility; hydrogen fluoride clean; interfacial layer; low-pressure chemical vapor deposition; mobility curve; nanolaminate; scattered electrical characteristics; surface treatment; surface-channel pMOSFET; Atomic layer deposition; Chemical vapor deposition; Dielectrics; Electrodes; Germanium silicon alloys; Hafnium oxide; MOSFETs; Silicon germanium; Surface treatment; Water;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2004.826523
