THERMAL OXIDATION EFFECT ON ELECTRICAL PROPERTIES OF MOS CAPACITORS WITH EMBEDDED Ge NANOCRYSTALS
https://doi.org/10.29235/1561-2430-2018-54-1-119-126
Abstract
A 2D layer of spherical, crystalline Ge nanodots embedded in a SiO2 layer was formed by low pressure chemical vapor deposition combined with furnace oxidation and rapid thermal annealing. The samples were characterized structurally by using transmission electron microscopy in plan-view and cross-section geometries. It was found that the formation of highdensity Ge dots took place due to oxidation induced by the Ge segregation. Electrical properties were controlled by measuring C–V and I–V characteristics after the formation of MOS capacitors in different oxidation conditions and the ambient medium. A strong evidence of the charge storage effect on the crystalline Ge-nanodot layer was demonstrated by the hysteresis behavior of the high-frequency C–V curves. It is shown that dry oxidation followed by its reduction increases the hysteresis value compared to wet oxidation conditions. This hysteresis behavior is discussed taking into account the decrease in the Ge concentration and a possible effect of low temperature GeO evaporation is followed by wet oxidation.
Supporting agencies: We would like to acknowledge support from the Belarusian Republican Foundation for Fundamental Research (Project No. T16P-167) and the Belarusian Scientific Research Program “Photonics, Optics- and Microelectronics” (Project No. 3.2.03.01)
About the Authors
A. G. Novikau
Belarusian State University, Minsk
Belarus
Senior Lecturer of the Physical Electronics and Nanotechnology Department, Faculty of Radiophysics and Computer Science
Belarus
Senior Lecturer of the Physical Electronics and Nanotechnology Department, Faculty of Radiophysics and Computer Science
O. Yu. Nalivaiko
Belarusian State University, Minsk
Belarus
Deputy Chief of Technology, Holding Company “Integral”
Belarus
Deputy Chief of Technology, Holding Company “Integral”
P. I. Gaiduk
Belarusian State University, Minsk
Belarus
D. Sc. (Physics and Mathematics), Assistant Professor, Professor of the Physical Electronics and Nanotechnology Department, Faculty of Radiophysics and Computer Science
Belarus
D. Sc. (Physics and Mathematics), Assistant Professor, Professor of the Physical Electronics and Nanotechnology Department, Faculty of Radiophysics and Computer Science
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