#Example 16.1 : concentration
#given data :
e=1.602*10**-19;# Coulomb
sigma_i=5*10**-4;# in ohm/m
mu_n=0.14;# in m**2/V-sec
mu_p=0.05;# in m**2/V-sec
n_i=sigma_i/(e*(mu_n+mu_p));
print round(n_i*10**6,-20),"= the concentration,n_i(/cm**3) "
#Example 16.2 : intrinsic carrier
#given data :
e=1.602*10**-19; # Coulomb
p_i=2*10**-4;# in ohm-m
mu_n=6;# in m**2/V-sec
mu_p=0.2;# in m**2/V-sec
n_i=1/(e*(mu_n+mu_p)*p_i);
print round(n_i,-19),"= the intrinsic carrier,n_i(/m**3) "
#Example 16.3 : neglect the intrinsic conductivity
#given data :
e=1.6*10**-19; # Coulomb
sigma=10**-12;# in mhos/m
mu_n=0.18;# in m**2/V-sec
n=sigma/(e*mu_n);
N=n; # amount of n type impurity
print "{:.2e}".format(N),"in(/m**3) "
# The answer is slightly different in textbook due to approximation
#Example 16.4 : number of electron carriers
#given data :
e=1.6*10**-19; # Coulomb
p=20*10**-2;# in ohm-m
mu_n=100*10**-4;# in m**2/V-sec
n=1/(e*mu_n*p);
print round(n,-19),"= number of electrons carrier,n(/m**3) "
#Example 16.5 : concentration of impurity
import math
e=1.6*10**-19;# Coulomb
l=10;#in mm
d=1;#in mm
r=100;#in ohms
up=0.19;#mobilty of electrons in V-sec
a=(math.pi*((d*10**-3)**2))/4;#area in m**2
p=((r*a))/(l*10**-3);#resistivity in Ohm-cm
n=((1/(p*e*up)));#concentration in per m**3
print round(n,-19),"is impurity concentration is in per m**3"
#Example 16.6 : intrinsic carrier density
#given data :
e=1.602*10**-19; # in coulomb
p=3000.0;# in ohm/m
sigma=1/p;# in ohm/m
mu_n=0.14;# in m**2/V-sec
mu_p=0.05;# in m**2/V-sec
n_i=sigma/(e*(mu_n+mu_p));
print round(n_i,-13),"is the concentration,n_i(/m**3) "
#Example 16.7 : conductivity
#given data :
e=1.602*10**-19; # in coulomb
n_i=5.021*10**15; # in m**-3
mu_n=0.48;# in m**2/V-sec
mu_p=0.013;# in m**2/V-sec
sigma=n_i*(e*(mu_n+mu_p));
print "{:.3e}".format(sigma),"= the conductivity,sigma(ohm**-1 m**-1) "