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  1. XIV. What does the above Table refer to ? Describe the meaning of the terms entered in the boxes ? Answer: The angle between the Primary Flat of the Si Wafer and the Secondary Flat of the Si Wafer is ‘α’. Type tells if Si-Wafer is N-Type or P-Type. Orientation gives the cleavage plane Orientation in Miller Indices.[1/6+1/6+1/6=1/2Point]

XV. What do the different terms refer to in the above Integral Equation? Answer: N(E)=density of states per unit volume per unit energy, P(E) →Fermi-Dirac Statistics or the probability of occupancy at energy E by Fermions. dE → elemental energy, m*→effective mass of electron in the conduction band.X 0 →Fermi Level in Metal with respect to the bottom edge of the Conduction Band i.e.X 0 =E F - E C .[1/10+1/10+1/10+1/10+1/10=1/2 Points]


In the adjacent equation and in Question XV, X 0 is the same parameter. What is this parameter. Answer: X 0 =E F - E C .[1/2 Point]


What are the different parameters and what are their units ? Answer: E g is Band-Gap in eV and λ is the wavelength of the photon emitted accompanying the radiative transition from Conduction Band to the Valence Band.[1/4+1/4=1/2]

XVIII. Define the parameters and give the units ?

Semiconductor E g n i ε r (DC) ? ρ i (300K) N C N V
Si 1.12 1×10 10 11.7 5×10 22 /cc 3.2×10 5 3.2×10 19 /cc 1.8×10 19 /cc
Ge 0.67 2×10 13 16.2 4.4×10 22 /cc 48 1×10 19 /cc 5×10 18 /cc
GaAs 1.424 2.1×10 6 12.9 4.42×10 22 /cc 3.3×10 8 4.7×10 17 /cc 7×10 18 /cc

Answers: E g (eV) , n i (#/cc), ε r (DC) rel.permittivity (Dimensionless ), #density of atoms in the crystal , ρ i (300K) Intrinsic Resistivity in Ω-cm, N C _ Effective Density of States at E C, N V _ Effective Density of States at E V [1/14+1/14+1/14+1/14+1/14+1/14+1/14=1/7]


Define the terms and give the units. v = 10 7 cm/s. What is this velocity. Answers: v drift = electric drift velocity(m/s), μ(mobility) (cm 2 /(V-s)), q=electric charge(Coulombs), τ scattering (Mean Free Path or Relaxation Time)(sec),m* e =effective mass of electron(Kg)[1/28,1/28,1/28,1/28,1/28,1/28,1/28, 1/28,1/28,1/28,1/28,1/28,1/28,1/28,=1/2]


This rule is called Matthiessen’s Rule. Define the parameter and give the units of the parameter. Answers:μ effective ,→ effective mobility, μ imp ,→mobility due to impurity scattering, μ lattice ,→mobility due to lattice scattering, cm 2 /(V-s), [1/8+1/8+1/8+1/8=1/2]


What are these power laws. Answers: lattice scattering inverse 3/2 power law , impurity scattering 3/2 power law [1/4+1/4=1/2 points]

XXII. σ = qμn Define the terms and give the units. Answers: σ →conductivity(Siemens/cm), q→electronic charge(Coulomb),μ→mobility(cm 2 /(V-s),n→conducting electron number density[1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16=1/2 Points]

XXIII. What special information is given by this Table.

Metal Au Cu Ni Pt
Effective Mass/Free Mass of electron 1.1 1.01 28 13

Answers: Ni and Pt are heavy Fermionic Metals [1/4+1/4=1/2]

XXIV. What is the basic difference about electron transport reflected by the Table below ?

Element E F τ(femtosec) L(Angstrom) W F v e 1 (×10 5 m/s)
Li 4.7 9 90 9.96
Na 3.1 31 250 2.3 8.08
K 2.1 44 293 2.2 6.55
Cu 7.0 27 328 12.15
Ag 5.5 41 441.6 10.77
Ge E V +E G /2 2217 2106 1.16
Si E V +E G /2 767.6 729 1.16
GaAs E V +E G /2 4890 4645.5 1.16

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
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Source:  OpenStax, Electrical and electronic materials science. OpenStax CNX. May 01, 2014 Download for free at http://cnx.org/content/col11615/1.14
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