Fig. 1.
Ge3d spectra analyzed by XPS for wafers with different process conditions
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Mei Zhao, Renrong Liang, Jing Wang, Jun Xu. Effective interface passivation of a Ge/HfO2 gate stack using ozone pre-gate treatment and ozone ambient annealing[J]. Journal of Semiconductors, 2013, 34(6): 066005. doi: 10.1088/1674-4926/34/6/066005
M Zhao, R R Liang, J Wang, J Xu. Effective interface passivation of a Ge/HfO2 gate stack using ozone pre-gate treatment and ozone ambient annealing[J]. J. Semicond., 2013, 34(6): 066005. doi: 10.1088/1674-4926/34/6/066005.
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Effective interface passivation of a Ge/HfO2 gate stack using ozone pre-gate treatment and ozone ambient annealing
doi: 10.1088/1674-4926/34/6/066005
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Abstract
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 6.4×1011 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. -
References
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