N.V. Cherkesova1, G.A. Mustafaev2, A.G. Mustafaev3

1,2 Kabardino-Balkarian State University (Nalchik, Russia)

3 MIREA – Russian Technological University (Moscow, Russia)

1 natasha07_2002@mail.ru, 2 zoone@mail.ru, 3 mustafaev@mirea.ru

Defects resulting from various technological processes and phenomena, such as ion implantation and hot electron injection, can significantly change the electrophysical parameters of MOS transistors, for example, the threshold voltage, leading to a decrease in their reliability and efficiency. It is necessary to identify the main mechanisms of these changes and determine the methods for their minimization. The purpose of the work is to investigate the effect of defects formed in the processes of ion implantation and subsequent hot electron injection on the threshold voltage of n-channel MOS transistors, as well as to determine the methods for reducing the negative effects by optimizing the implantation and annealing conditions. It was found that ion implantation causes a significant negative shift in the threshold voltage due to the formation of a positive charge in the gate oxide. Hot electron injection leads to a positive shift in the threshold voltage due to the capture of electrons by neutral traps. It is shown that the degradation of the characteristics of MOS transistors is associated mainly with the charge of the gate electrode during implantation, and not with the ion bombardment itself. Grounding the gate during implantation significantly reduces the negative impact. The results obtained allow us to better understand the mechanisms of changing the characteristics of MOS transistors under the influence of technological processes. This can be used to develop effective methods for manufacturing microcircuits, where minimizing defects and increasing the reliability of transistors is important. The proposed measures, such as grounding the gate during implantation, are easy to implement and can be introduced into modern technologies for the production of microelectronic devices.

Cherkesova N.V., Mustafaev G.A., Mustafaev A.G. Effect of ion implantation and hot electrons on the threshold voltage of MOSFETs. Electromagnetic waves and electronic systems. 2025. V. 30. № 6. P. 78−83. DOI: https://doi.org/10.18127/j15604128-202506-07 (in Russian)

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