Question

sketch vertical structure of power transistor and describe properties of any two reasons

Answer 1

This technical article is dedicated to the review of the following power electronics devices which act as solid-state switches in the circuits. They act as a switch without any mechanical movement.

Power Diodes
Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET)
Bipolar -Junction Transistor (BJT)
Insulated-Gate Bipolar Transistor (IGBT)
Thyristors (SCR, GTO, MCT)

Answer 2

Power transistors are devices that have controlled turn-on and turn-off characteristics.These devices are used a switching devices and are operated in the saturation region resulting in low on-state voltage drop. They are turned on when a current signal is given to base or control terminal. The transistor remains on so long as the control signal is present. The switching speed of modern transistors is much higher than that of Thyristors and are used extensively in dc-dc and dc-ac converters. However their voltage and current ratings are lower than those of thyristors and are therefore used in low to medium power applications. Power transistors are classified as follows

Bipolar junction transistors(BJTs) Metal-oxide semiconductor filed-effect transistors(MOSFETs) Static Induction transistors(SITs) Insulated-gate bipolar transistors(IGBTs)