PA2230___Condensed_Matter

Question 1

Density of a “Unit Cell” Equation:

Answer 1

Question 2

N.N. for an fcc

Answer 2

Question 3

N.N. for a bcc

Answer 3

Question 4

Number of “Element: x” atoms per unit volume:
(Value of “x” donor concentration per unit volume)

Answer 4

Question 5

Energy Band gap of a semiconducting material
(When given wavelength)

Answer 5

Question 6

Extrinsic:
(Definition)

Answer 6

A semiconductor that has been doped

Question 7

Doping:

Answer 7

Deliberate addition of impurities in a controlled way

Question 8

Purpose of Doping:

Answer 8

Allows tailoring of the charge carrier concentrations to desired values

Question 9

n-type semiconductor:
(Definition)

Answer 9

A semiconductor doped with donor impurities

Question 10

p-type Semiconductor:
(Definition)

Answer 10

Acceptor-doped semiconductors

Question 11

Sketch of n-type extrinsic sc & its energy levels:

Answer 11

Question 12

Sketch of p-type extrinsic sc & its energy levels:

Answer 12

Question 13

m* derivation:

Answer 13

Question 14

Effective Mass

Answer 14

Question 15

Meaning negative effective mass

Answer 15

Electrons at the top of the energy band with negative effective mass are known as “holes” in the valence band.
A positive charged particle with equal magnitude of an electron.

Question 16

Effective density of states at the band edges

Answer 16

N_c

Question 17

Electrical Conductivity
(Equation)

Answer 17

Question 18

Fermi Energy:
(In terms of Conduction & Valence Energy

Answer 18

Question 19

Electric Conductivity
(Extrinsic n-type)

Answer 19

Question 20

Intrinsic s/c property

Answer 20

Question 21

Law of Mass Action
(Intrinsic s/c)

Answer 21

Question 22

Law of Mass

Answer 22

Question 23

k value at 1st Brillouin Zone

Answer 23

Question 24

Intrinsic
(definition)

Answer 24

A pure semiconductor that has not been doped with impurities

Question 25

Energy gap
(When given wavelength)

Answer 25