Test for OMEN Nanowire Lab
(http://nanohub.org/tools/omenwire)
Note: only one choice is correct
1.
What is the main reason the nanowire transistor possibly can substitute the
conventional planar MOSFET?
a. small short channel effect
b. small ballistic mobility
c. large subthreshold slope
2.
The benefit that the nanowire transistors can offer in problem 1 is possible
because the quantum capacitance in nanowire is much smaller than the oxide
capacitance. What would result in a small quantum capacitance in a nanowire
transistor as compared to a conventional MOSFET?
a. small mobility
b. large ON-current
c. small density of states
3.
How many dimension(s) of a nanowire is(are) confined in real space?
a. 1
b. 2
c. 3
4.
Which of the following methods does OMEN Nanowire use to calculate the
transport property of a nanowire transistor?
a. effective approximation
b. wavefunction formalism
c. Boltzmann transport equation
5.
Which of the following is used in OMEN Nanowire to calculate the
bandstructure?
a. tight-binding model
b. abinitio model
c. nearly free electron model
6.
Suppose you have measured three (Id,Vg) pairs for a nanowire transistor at high
drain bias: (1e-10 A,0 V) (1e-9 A,0.1 V), (1e-8 A,0.2 V). What is the
subthreshold slope?
a. 120 mV/dec
b. 110 mV/dec
c. 100 mV/dec
7.
How does the tensile hydrostatic strain change the drain current of a nanowire
transistor?
a. increase
b. decrease
c. no change
8.
Why would a ballistic simulation without scattering suffer a convergence problem
at high gate bias?
a. drain induced barrier lowering
b. threshold voltage roll-off
c. source starvation
9.
Where would the electrons mainly flow in a circular nanowire transistor with
diameter less than 3 nm?
a. center
b. surface
c. zigzag
10.
How would density of states vs energy (DOS vs E) look like in a nanowire?
a. step function
b. inverse square root function
c. delta function
11.
How is the current density (spectra) calculated in OMEN nanowire?
a. electron energy * Fermi function difference (=fL-fR)
b. density of states * Fermi function difference (=fL-fR)
c. transmission * Fermi function difference (=fL-fR)
12.
What will cause a large OFF-current in a nanowire transistor with a short channel
length?
a. ballistic transport
b. tunneling of electrons through the barrier
c. electron-electron scattering