{
"metadata": {
"name": "",
"signature": "sha256:dd227268a9d19f5e7b124ff2e3d8219b9fcc3bf4655f5f8e908de4958335cce5"
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 11: Semiconductor Theory and Devices"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.1, Page 400"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import numpy\n",
"import math\n",
"\n",
"#Variable declaration\n",
"e = 1.6e-019; # Energy equivalent of 1 eV, J\n",
"k = 1.38e-023; # Boltzmann constant, J/K\n",
"T = 293; # Room temperature, K\n",
"\n",
"#Calculations&Results\n",
"dE = [0.10, 1.0, 10.0]; # Energies above the valence band, eV\n",
"F_FD = numpy.zeros(3);\n",
"for i in range(0,3):\n",
" F_FD[i] = 1/(math.exp(dE[i]*e/(k*T)) + 1);\n",
" print \"For E - E_F = %4.2f eV, F_FD = %4.2e\"%(dE[i], F_FD[i])\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"For E - E_F = 0.10 eV, F_FD = 1.88e-02\n",
"For E - E_F = 1.00 eV, F_FD = 6.53e-18\n",
"For E - E_F = 10.00 eV, F_FD = 1.40e-172\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.3, Page 402"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"e = 1.6e-019; # Energy equivalent of 1 eV, J\n",
"rho = 5.92e-008; # Resistivity of the zinc at room temperature, ohm-m\n",
"B = 0.25; # Magnetic field applied perpendicular to the strip, T\n",
"x = 10.0e-002; # Length of the zinc strip, m\n",
"y = 2.0e-002; # Width of the zinc strip, m\n",
"V = 20e-003; # Potential difference applied across the strip, V\n",
"I = 0.400; # Current through the strip, A\n",
"V_H = 0.56e-006; # Hall voltage that appeared across the strip, V\n",
"\n",
"#Calculations\n",
"z = rho*x*I/(y*V); # Thickness of the strip, m\n",
"n = I*B/(e*V_H*z); # Number density of the charge carriers, per metre cube\n",
"\n",
"#Results\n",
"print \"The thickness of the zinc strip = %4.2e m\"%z\n",
"print \"The number density of the charge carriers = %4.2e per metre cube\"%n\n",
"print \"The charge carries in zinc are positive.\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The thickness of the zinc strip = 5.92e-06 m\n",
"The number density of the charge carriers = 1.89e+29 per metre cube\n",
"The charge carries in zinc are positive.\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.4, Page 408"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"#Variable declaration\n",
"e = 1.602e-019; # Energy equivalent of 1 eV, J\n",
"k = 1.38e-023; # Boltzmann constant, J/K\n",
"T = 293; # Room temperature, K\n",
"V_f = 0.200; # Forward voltage, V\n",
"I_f = 50e-003; # Forward current, A\n",
"V_r = -0.200; # Reverse voltage, V\n",
"\n",
"#Calculations\n",
"I_r = I_f*(math.exp(e*V_r/(k*T))-1)/(math.exp(e*V_f/(k*T)) - 1); # Reverse current from diode equation, A\n",
"\n",
"#Result\n",
"print \"The reverse current through pn-junction diode = %2d micro-ampere\"%(I_r/1e-006)"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The reverse current through pn-junction diode = -18 micro-ampere\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.5, Page 413"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"#Variable declaration\n",
"A = 100*100; # Area of solar cell, Sq.m\n",
"t = 12*60*60; # Time for which the solar cell operates, s\n",
"phi = 680; # Solar flux received by the solar cell, W/Sq.m\n",
"eta = 0.30 # Efficiency of the solar array\n",
"\n",
"#Calculations&Results\n",
"E_array = eta*phi*A*t; # Energy produced by solar cell in one 12-hour day, J\n",
"print \"The energy produced by solar cell in one 12-hour day : %3.1e J\"%E_array\n",
"P = 100e+006; # Power output of power plant, W\n",
"t = 24*60*60; # Time for which power plant operates, s\n",
"E_plant = P*t; # Energy produced by power plant, J\n",
"print \"The energy produced by power plant in one day : %3.1e J which is about %d times more than that produced by solar cell array..!\"%(E_plant, math.ceil(E_plant/E_array))"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The energy produced by solar cell in one 12-hour day : 8.8e+10 J\n",
"The energy produced by power plant in one day : 8.6e+12 J which is about 99 times more than that produced by solar cell array..!\n"
]
}
],
"prompt_number": 4
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.6, Page 418"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"\n",
"#Variable declaration\n",
"r1 = 2.30e-002; # Radius of inner edge of storing region of CD-ROM, m\n",
"r2 =5.80e-002; # Radius of outer edge of storing region of CD-ROM, m\n",
"A = math.pi*(r2**2 - r1**2); # Area of the usable region of CD-ROM, Sq.m\n",
"N = 700e+006*8; # Total number of bits in CD-ROM\n",
"\n",
"#Calculations\n",
"APB = A/N; # Area per bit of CD-ROM, Sq.m/bit\n",
"t = 1.6e-006; # Track width of CD_ROM, m\n",
"l = APB/t; # Bit length, m\n",
"\n",
"#Results\n",
"print \"The surface area of CD-ROM allowed for each data bit = %3.1e Sq.m/bit\"%APB\n",
"print \"The approx. dimensions of each bit along the track = %1.0f micro-metre\"%(l/1e-006)"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The surface area of CD-ROM allowed for each data bit = 1.6e-12 Sq.m/bit\n",
"The approx. dimensions of each bit along the track = 1 micro-metre\n"
]
}
],
"prompt_number": 5
}
],
"metadata": {}
}
]
}