Abstract
Operation of the high-power thyristor without bias voltage switching in the impact-ionization mode was studied by numerical simulation methods. In calculations, the rate of voltage build-up on the dV/dt structure varied from 0.5 to 10 kV/ns, the temperature of the T structure was from 25 to 200 °C. It is shown that the increase in temperature affects the process of switching thyristors both due to an increase in the rate of thermal generation of carriers, and due to a decrease in the intensity of impact ionization processes. During switching processes of impact ionization occur at the same time in two regions of n-base: in the part of a base filled with the majority carriers and in the space charge region (SCR) near the n-p junction. At T>180 °C, owing to increase in concentration of thermo-generated carriers in the base, ionization processes occur only in SCR. It leads to increase in duration of switching process and increase in residual voltage. However, despite it if dV/dt>9 kV/ns, the effect of fast switching of the thyristor exists up to 200 °C.
Highlights
In the last decade semiconductor switches on the basis of dynistor structures with a time of transition into a conducting state for less than 1 ns were developed [1, 2]
It is shown that the increase in temperature affects the process of switching thyristors both due to an increase in the rate of thermal generation of carriers, and due to a decrease in the intensity of impact ionization processes
During switching processes of impact ionization occur at the same time in two regions of n-base: in the part of a base filled with the majority carriers and in the space charge region (SCR) near the n-p junction
Summary
In the last decade semiconductor switches on the basis of dynistor structures with a time of transition into a conducting state for less than 1 ns were developed [1, 2]. In compliance with the results received in [10, 11], the model includes the following provisions: (a) to avoid triggering the front due to the avalanche propagation of unphysically small concentrations of free carriers [5], impact ionization processes are activated at the time when the carrier concentration at any point of the structure reaches the value n0 =0.5· 109 cm-3, (b) the concentration of deep M-type levels (0.54 eV) is NPI =1012 cm-3, (c) the dependence of the active area of the structure through which the thyristor switches to the conductive state on the rate of voltage dV/dt is taken into account [11]. The magnitude of the initial bias voltage V0 was 0 kV
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
