Mid-Term Examl (ECE 128 Electronics 1) Name: I. (a) The phosphorus atom is calle
ID: 1766252 • Letter: M
Question
Mid-Term Examl (ECE 128 Electronics 1) Name: I. (a) The phosphorus atom is called a ( (b) The boron atom is called a )impurity. (Ipts) (c) Among two basic processes that cause electrons and holes to move in a ) impurity. (Ipts) semiconductor, what is the name of the process due to the variations in the concentration of carriers? (2pts) (d) In the pn-junction, what is the name of region that does not have any carriers when there is no bias? (2pts) (e) In an n-channel MOSFET, the ) layer exists when the gate voltage is greater than the threshold voltage of Vs. (2pts) () Among n-channel MOSFETs, it is called a ( )-mode MOSFET when the channel exists when zero volts are applied to the gate generating drain to source current. (2pts)Explanation / Answer
a). Phosphorus atom is called a pentavalent impurity Because it has five valence elecrons.
b).Boron atom is called a tetravalent impurity Because it has three valence elecrons.
c). Drift and Diffussion.
d).Depletion Region because it is depleted with carriers.
e).In n-channel mosfet the inversion layer exists at gate voltage higher than threshold.
f).Depletion mode mosfet.