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• Carbon pre-implantation improves the thermal stability of NiSi. • Carbon clusters are formed the vicinity of NiSi/Si interface. • NiSi agglomeration suppressed by carbon clusters formed at the NiSi/Si interface. • Ni diffusion is inhibited by carbon clusters at the interface of NiSi/Si. • The effect of carbon pre-implantation could be analyzed using atom probe at near-atomic scale. We have investigated effects of carbon pre-implantation (C-implantation) on electrical and morphological properties of nickel silicide (NiSi). C-implanted NiSi showed an improved thermal stability on the electrical characteristics in terms of sheet resistance (R sh) and contact resistivity (ρ c) after rapid thermal annealing (RTA) up to 700 °C. The process temperature window was extended by ~100 °C when the C-implantation with a dose of 1 × 1015 cm−2 was introduced. From transmission electron microscopy (TEM) images, the suppression of NiSi agglomeration was confirmed in the C-implanted NiSi. In order to further understand the role of carbon, atom probe tomography (APT) was performed. The three-dimensional (3D) distribution and composition of elements by APT unveiled the formation of carbon clusters with a diameter ranging from 2 to 10 nm near the NiSi/Si interface. The carbon clusters with a peak concentration of 6.0 at. % at the NiSi/Si interface can effectively suppress NiSi agglomeration and Ni diffusion, resulting in improving thermal stability of the NiSi. [ABSTRACT FROM AUTHOR]

The spatial position and energy level of the effective oxide trap in SiC DMOSFET were investigated using Trap Spectroscopy by Charge Injection and Sensing (TSCIS) method. It was found that the oxygen vacancy traps at 1.7 eV above from the valence band of SiO 2 make threshold voltage (V th ) shift under high negative gate bias stress condition. To further understanding the extracted oxide trap, the repetitive negative stress and recovery test at V G = ±40 V were executed. The results confirm that V th and subthreshold swing (SS) change were caused by the process induced pre-existed hole traps instead of the stress induced trap generation. This hole trapping also reduced the Stress Induced Leakage Current (SILC) after the negative bias stress. [ABSTRACT FROM AUTHOR]