The transfer characteristic of a MOSFET is observed as shown: Th

SOLUTION

An enhancement type MOSFET requires some minimum Voltage (V_th) for a channel to get induced.

The current Equation for an Enhancement Type MOSFET is given by:

\({{I}_{d}}\left( sat \right)={{K}_{n}}\left[ {{\left( {{V}_{GS}}-{{V}_{th}} \right)}^{2}} \right]\) 

V_th is the minimum voltage required for the channel to get induced.

1) For V_GS = 0, there will be no channel, resulting in no current to flow for positive V_DS

2) For the given transfer characteristic, I_D(mA) is not zero for V_GS = 0, which indicates that there is already a channel induced for V_GS = 0.

So, the given MOSFET is a depletion type MOSFET.

Also, for positive V_GS, I_D = 0 and for negative V_GS, I_D is increasing, indicating that the channel is p-channel.