In [1]:

```
#initiation of variable
sigma=10**-6 # ( Electrical Conductivity in Ohm-m)^-1
e=1.6*10**-19 # Charge on electron in Coulomb
m_e=0.85 #Mobility of electron in m^2/V-s
m_h=0.04 # Mobility of holes in m^2/V-s
#calculation
n_i=sigma/(e*(m_e+m_h))#n_i is Intrinsic carrier concentration
#result
print" Intrinsic Carrier Concentration is %.1e m^-3" %n_i;
```

In [2]:

```
#initiation of variable
e=1.6*10**-19 #Charge on electron in Coulomb
ni=4*10**19 # number of electron per unit volume for Si at 423 K (m^-3)
#Values of m_e and m_h are deduced from graphs at page No.689
m_e=0.06 #Mobility of electron in m^2/V-s
m_h=0.022 # Mobility of holes in m^2/V-s
#calculation
sigma=ni*e*(m_e+m_h) # electrical conductivity
#result
print" Electrical Conductivity is %.2f (Ohm-m)^-1\n" %sigma
```

In [4]:

```
#initiation of variable
n=10.0**23 # Carrier Concentration in m^-3
e=1.6*10**-19 #Charge on electron in Coulomb
#From graph 18.18 m_e is calculated corresponding to n=10^23
m_e=0.07 # Mobility of electron in m^2/V-s
m_e2=0.04 # Mobility of electron m^2/V-s
#part A
#result
print" Material is n-type "
# Part B
#calculation
sigma=n*e*m_e # electrical conductivity calculation for extrinsic n-type
#result
print "Conductivity is just %d (Ohm-m)^-1" %sigma
#partC
#From graph 18.19a m_e2 is calculated corresponding to 373 K
sigma2=n*e*m_e2
#result
print"Conductivity at T=373 K becomes %d (Ohm-m)^-1\n" %sigma2;
```

In [9]:

```
#intiiation of variable
sigma=3.8*10**7 # Electrical Conductivity in (Ohm-m)^-1
m_e=0.0012 # Mobility of electron in m^2/V-s
I_x=25.0 # Current in Ampere(A)
d=15.0*10**-3 #Thickness in m
B_z=0.6 # Magnetic field in Tesla
#calculation
Rh=-m_e/sigma #Hall coefficient
Vh=Rh*I_x*B_z/d
#result
print" Hall coefficient is %.2e V-m/A-Tesla" %Rh
print"Hall Voltage is %.2e V" %Vh
```

In [11]:

```
#initiation of variable
from math import ceil
A = 6.45e-4 # Area of plat in m^2
l = 2.0e-3 # separation between plates in m
epsilon_r = 6.0 #dielectric constant of material
epsilon_0 = 8.85e-12 # universal constant
V = 10.0 # Applied voltage in Volt
# Part A
#calculation
C = epsilon_0*epsilon_r*A/l #Capacitance of a parallel plat capacitor
#result
print" Capacitance of capacitor is %.2e F" %C
#partB
Q = C*V # Stored charge calculation
#result
print" Stored charge in capacitor is %.2e C" %Q
#partC
D = epsilon_0*epsilon_r*V/l # Dielectric displacement
#result
print" Dielectric displacement in capacitor is %.2e C/m^2" %(ceil(D*1e9)/1e9)
#partD
P = D - epsilon_0*V/l # Polarisation
#result
print" Polarization is %.2e C/m^2" %(ceil(P*1e9)/1e9)
```

In [15]:

```
#initiation of variable
p1 = 1.0e22 # Number of electrons per unit volume
e = 1.6e-19 # Charge on electron in coulomb
mu_h1 = 0.04 # concentration of holes mobility in m^/Vs
sigma_d = 50.0 # Desired conductivity in (ohm-m)^-1
p2 = 1.0e21# Number of electrons per unit volume
mu_h2 = 0.045#concentration of holes mobility in m^/Vs
p3 = 8.0e21# Number of electrons per unit volume
mu_h3 = mu_h1# concentration of holes mobility in m^/Vs
N_a = 6.023e23 # Avogadro’s constant
rho_si = 2.33e6 # density of silicon in g/m^3
A_si = 28.09 # molecular weight in g/mol
#calculation
sigma1 = p1*e*mu_h1
sigma2 = p2*e*mu_h2
sigma3 = p3*e*mu_h3
N_Si = N_a*rho_si/A_si
Ca = p3*100/(p3+N_Si)
#result
print " Silicon material of p-type of conductivity %d (ohm-m)^-1" %sigma_d, " must have %.2e doping material" %Ca
```