36 lines
931 B
Python
36 lines
931 B
Python
from math import log, sqrt
|
|
|
|
V_t0 = 0.7 # The nominal threshold voltage
|
|
t_ox = 100E-8 # The gate threshold voltage in angstrom with CGS units
|
|
N_A = 2E17 # The doping level in cm^-3
|
|
|
|
k_ox = 3.9
|
|
k_si = 11.7
|
|
eps_0 = 8.85E-14 # Vacuum permittivity with CGS units
|
|
k = 1.380E-23 # Boltzmann's constant
|
|
q = 1.602E-19 # The charge of an electron
|
|
|
|
T = 300 # Room temperature in Kelvin
|
|
|
|
v_T = k*T/q
|
|
n_i = 1.45E10 # The intrinsic carrier concentration of undoped Si
|
|
|
|
eps_ox = k_ox * eps_0
|
|
eps_si = k_si * eps_0
|
|
|
|
V_b = 0
|
|
V_s0 = 0
|
|
V_s1 = 4
|
|
|
|
gamma = (t_ox / eps_ox) * sqrt(2*q*eps_si*N_A)
|
|
phi_s = 2 * v_T * log(N_A / n_i)
|
|
|
|
def V_t(V_t0, V_s, V_b, gamma, phi_s):
|
|
V_sb = V_s - V_b
|
|
return V_t0 + gamma*(sqrt(phi_s + V_sb) - sqrt(phi_s))
|
|
|
|
Delta_V_t = V_t(V_t0, V_s1, V_b, gamma, phi_s) \
|
|
- V_t(V_t0, V_s0, V_b, gamma, phi_s)
|
|
|
|
print(Delta_V_t)
|