fundamentals of the metal-oxide-semiconductor field-effect transistor and its applications
Post on 20-Dec-2015
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enhancement n-channel MOSFET
222 DSDSTGS
oxnD VVVV
L
CWI
2
2 TGSoxn
D VVL
CWI
Non-saturation: Saturation:
transconductance
GS
Dm V
Ig
DSoxn
GS
DmL V
L
CW
V
Ig
TGSoxn
GS
Dms VV
L
CW
V
satIg
Non-saturation:
Saturation:
I-V relationship….11.3.3
1. The current in the channel is due to drift rather than diffusion.
2. There is no current through the gate oxide.
3. A gradual channel approximation is used in which . This approximation means that Ex is essentially a constant.
4. Any fixed oxide charge is an equivalent charge density at the oxide-semiconductor interface.
5. The carrier mobility in the channel is constant.
x
E
y
Exy