Body effect MOSFET
The MOSFET is known as the field-effect transistor type, technically it is made by joining the semiconductor material together.
A MOSFET is a 3 three-terminal device but actually, they had an extra terminal called the body, in this article we explain a phenomenon that happened at the body terminal of the MOSFET.
What is body effect in MOSFET?
- We mentioned earlier that the body is the fourth terminal at the MOSFET, they have a P+ charge at the device.
- The body effect is happened due to a change in source voltage at the MOSFET.
- In normal cases the source terminal is grounded, if any change happened on the voltage of the source, say 1v passes towards the source, VB= body voltage, and Vs = source voltage. VB < VS.
- The body terminal or bulk terminal releases electrons, and that electrons accumulated in the gate region.
- This will cause the depletion region width, it increases and naturally, that will be affected on the threshold voltage.
- This effect is called the body effect on MOSFET.
How to reduce body effect in MOSFET
For to reduce the body effect in MOSFET, we need to maintain the source voltage and body voltage on the same level.
Body effect in MOSFET will affect
Body effect will affect the MOSFETs threshold voltage, say if the normal threshold voltage Vth of MOSFET is between 0.7 to 1v, which would changes into 0.8 to 2v.
The increase in threshold voltage is a loss for the overall component working.