Substrate bias effect and body effect are two common effects in semiconductor devices.

Substrate Bias Effect: Refers to the effect of the potential difference between the substrate and the gate on the conductivity of the MOSFET.

The substrate bias effect can be changed by adjusting the substrate voltage to control the conduction and cut-off of the MOSFET.

Body Effect: Due to the different doping concentrations, the potential differences in different regions affect the electrical performance of the device. It is mainly caused by the change in electric field due to the change in source/drain voltage.

The body effect can be changed by adjusting the gate voltage to control the conduction and cut-off of the MOSFET.

The differences between the two are:

The substrate bias effect is caused by the change in gate voltage, while the body effect is caused by the change in source/drain voltage.

The substrate bias effect mainly affects the drain current, while the body effect mainly affects the gate current.

The effects of substrate bias effect and body effect on the performance of the MOSFET are:

The substrate bias effect can cause changes in the drain current, increasing the relationship between the threshold voltage and the drain current, affecting the operating point and output characteristics of the MOSFET.

The body effect can cause changes in the gate current, increasing the relationship between the drain current and the source/drain voltage, affecting the conduction characteristics and output characteristics of the MOSFET.

Methods to reduce the effects of substrate bias effect and body effect include:

Using a MOSFET with a long channel, where the channel length is longer, reducing the change in the electric field, thereby reducing the effects of substrate bias effect and body effect.

Reduce the doping concentration of the substrate, or reduce the thickness of the oxide layer (enhance the control ability of the gate).

Using negative feedback technology, by introducing a compensating circuit to reduce the effects of substrate bias effect and body effect.