Sketch density state function, Fermi-Dirac probability function,
and areas representing electron and hole concentrations for the...
Sketch density state function, Fermi-Dirac probability function,
and areas representing electron and hole concentrations for the
case Ef below the intrinsic Fermi energy.
You are given an intrinsic silicon at “some”
temperature. It is known that the Fermi-Dirac probability for
electrons at the conduction band edge is Fe(EC)=1∗10−5. Answer the
following questions:
Hint: Even though it looks like a calculation
question, it is not. You should be able to “see” the answer
directly even without using the formula of the Fermi-Dirac
function.
1.What is the Fermi-Dirac probability for electrons at
the valence band edge Fe(EV)?
2.What is the Fermi-Dirac probability for holes
at...
For a 3D free electron gas, derive expressions for the Fermi
momentum, Fermi energy, and density of levels. Then plot the
density of levels and contrast its behavior as a function of
energy. Your answers should be expressed in terms of the electron
concentration n = N / V and some combination of fundamental
constants.
The radial probability density for the electron in the ground
state of a hydrogen atom has a
peak at about:
A. 0.5pm
B. 5 pm
C. 50pm
D. 500pm
E. 5000pm
ans: C
Chapter
The equilibrium electron concentration is given by the product
of density of states and probability function, n(E) =
g_c(E)F(E)n(E)=gc(E)F(E) whereg_c(E)gc(E) and F(E)F(E) are the
conduction band density of states and Fermi-Dirac probability
function, respectively
Using the full expression of Fermi-Dirac function, calculate the
energy relative to the conduction band edge, E-E_cE−Ec, at which
the electron concentration becomes maximum. This semiconductor has
a bandgap of 1.124 eV and the temperature is 300 K. Further assume
that the Fermi level, E_FEF is...
Sketch the spatial distribution of the electron density for all
of the valence orbitals of one of the carbon atoms in each of the
following molecules, Identify each of the orbitals.
a) Acetylene
b) Ethylene
c) Ethane
The random variables X and Y have the following probability
density function (pdf).
Conditional probability density function is
f(xly) = ax/y^2 , 0<x<y, 0<y<1
=0 , o/w
marginal density finction is
f(y) = by^4 ,0<y<1
= 0, o/w
At this time, find the constant a and b values to be the
probability density function, and then indicate whether the random
variables X and Y are independent, and if not, indicate whether
they are positive or inverse.