Question

Difference between MOSFET and JFET?

Answer 1

In MOSFET gate is of metal and is insulated with the conduction channel of transistor with a silicon dioxide layer. On the other side in JFET gate terminal is of semiconductor material and is not insulated with the channel. Remember in JFET channel and gate are different type of extrinsic semiconductor. In both case gate voltages control the conduction in the channel.

Answer 2

The gate terminal in MOSFET is isolated from conduction channel with a very thins silicon oxide layer. Hence, the name Metal Oxide Semiconductor FET. Its input resistance is very high due to thin Silicon oxide layer.