Unformatted text preview: condition for a MOS capacitor assuming the work function of the metal is NOT the same as that of the semiconductor? Is this a positive or negative value? VFB = MS, normally MS < S therefore VFB is negative. e. What is a depletion mode MOSFET? What is an enhancement mode MOSFET? A channel exists in a depletion mode MOSFET when the gate voltage is zero. A depletion mode device is “normally on”. A channel does NOT exist in an enhancement mode device when the gate voltage is zero. An enhancement mode device is “normally off”. f. In order to create a channel in an enhancement mode MOSFET with an n‐type substrate is a negative or positive voltage applied to the gate? What type of carrier is in the channel? To create a channel in an enhancement mode MOSFET with an n‐type substrate, a negative voltage must be applied to the gate. Holes form the channel in an n‐type substrate MOSFET. Problem #2: Problem #3: (c)...
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- Winter '08
- ideal mos capacitor, enhancement mode MOSFET