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{
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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 9:Semiconductors"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.2 , Page no:272"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "Eg=0.67; #in eV (Energy band gap)\n",
      "k=1.38E-23; #in J/K (Boltzmann\u2019s constant)\n",
      "T1=298; #in K (room temperature)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "K=10; #ratio of number of electrons at different temperature\n",
      "\n",
      "#calculate\n",
      "Eg=Eg*e; #changing unit from eV to Joule\n",
      "#since ne=Ke*exp(-Eg/(2*k*T))\n",
      "#and ne/ne1=exp(-Eg/(2*k*T))/exp(-Eg/(2*k*T1)) and ne/ne1=K=10\n",
      "#therefore we have 10=exp(-Eg/(2*k*T))/exp(-Eg/(2*k*T1))\n",
      "#re-arranging the equation for T, we get T2=1/((1/T1)-((2*k*log(10))/Eg))\n",
      "T=1/((1/T1)-((2*k*math.log(10))/Eg)); #calculation of the temperature\n",
      "\n",
      "#result\n",
      "print\"The temperature at which number of electrons in the conduction band of a semiconductor increases by a factor of 10 is T=\",round(T),\"K            (roundoff error)\";\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The temperature at which number of electrons in the conduction band of a semiconductor increases by a factor of 10 is T= 362.0 K            (roundoff error)\n"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.3 , Page no:272"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "ni=2.5E13; #in /cm^3 (intrinsic carrier density)\n",
      "ue=3900; #in cm^2/(V-s) (electron mobilities)\n",
      "uh=1900; #in cm^2/(V-s) (hole mobilities)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "l=1; #in cm (lenght of the box)\n",
      "b=1;h=1; #in mm (dimensions of germanium rod )\n",
      "\n",
      "#calculate\n",
      "ni=ni*1E6; #changing unit from 1/cm^3 to 1/m^3\n",
      "ue=ue*1E-4; #changing unit from cm^2 to m^2\n",
      "uh=uh*1E-4; #changing unit from cm^2 to m^2\n",
      "sigma=ni*e*(ue+uh); #calculation of conductivity\n",
      "rho=1/sigma; #calculation of resistivity\n",
      "l=l*1E-2; #changing unit from mm to m for length\n",
      "A=(b*1E-3)*(h*1E-3); #changing unit from mm to m for width and height and calculation of cross-sectional area\n",
      "R=rho*l/A; #calculation of resistance\n",
      "\n",
      "#result\n",
      "print\"The resistance of intrinsic germanium is R=\",R,\"ohm\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The resistance of intrinsic germanium is R= 4310.34482759 ohm\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.4 , Page no:273"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "ne=2.5E19; #in /m^3 (electron  density)\n",
      "nh=2.5E19; #in /m^3 (hole density)\n",
      "ue=0.36; #in m^2/(V-s) (electron mobilities)\n",
      "uh=0.17; #in m^2/(V-s) (hole mobilities)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "\n",
      "#calculate\n",
      "#since ne=nh=ni,  therefore we have \n",
      "ni=nh;\n",
      "sigma=ni*e*(ue+uh); #calculation of conductivity\n",
      "rho=1/sigma; #calculation of resistivity\n",
      "\n",
      "#result\n",
      "print\"The conductivity of germanium is =\",round(sigma,2),\"/ohm-m\";\n",
      "print\"The resistivity of germanium is =\",round(rho,2),\"ohm-m\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The conductivity of germanium is = 2.12 /ohm-m\n",
        "The resistivity of germanium is = 0.47 ohm-m\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.5 , Page no:273"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "ni=1.5E16; #in /m^3 (intrinsic carrier density)\n",
      "ue=0.135; #in m^2/(V-s) (electron mobilities)\n",
      "uh=0.048; #in m^2/(V-s) (hole mobilities)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "ND=1E23; #in atom/m^3 (doping concentration)\n",
      "\n",
      "#calculate\n",
      "sigma_i=ni*e*(ue+uh); #calculation of intrinsic conductivity\n",
      "sigma=ND*ue*e; #calculation of conductivity after doping\n",
      "rho=ni**2/ND; #calculation of equilibrium hole concentration\n",
      "\n",
      "#result\n",
      "print\"The intrinsic conductivity for silicon is =\",sigma_i,\"S\";\n",
      "print\"The conductivity after doping with phosphorus atoms is =\",sigma,\"S\";\n",
      "print\"The equilibrium hole concentration is =\",rho,\"/m^3\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The intrinsic conductivity for silicon is = 0.0004392 S\n",
        "The conductivity after doping with phosphorus atoms is = 2160.0 S\n",
        "The equilibrium hole concentration is = 2250000000.0 /m^3\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.6 , Page no:274"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "ni=1.5E16; #in /m^3 (intrinsic carrier density)\n",
      "ue=0.13; #in m^2/(V-s) (electron mobilities)\n",
      "uh=0.05; #in m^2/(V-s) (hole mobilities)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "ne=5E20; #in /m^3 (concentration of donor type impurity)\n",
      "nh=5E20; #in /m^3 (concentration of acceptor type impurity)\n",
      "\n",
      "#calculate\n",
      "#part-i\n",
      "sigma=ni*e*(ue+uh); #calculation of intrinsic conductivity\n",
      "#part-ii\n",
      "#since 1 donor atom is in 1E8 Si atoms, hence holes concentration can be neglected\n",
      "sigma1=ne*e*ue; #calculation of conductivity after doping with donor type impurity\n",
      "#part-iii\n",
      "#since 1 acceptor atom is in 1E8 Si atoms, hence electron concentration can be neglected\n",
      "sigma2=nh*e*uh; #calculation of conductivity after doping with acceptor type impurity\n",
      "\n",
      "#result\n",
      "print\"The intrinsic conductivity for silicon is =\",sigma,\"(ohm-m)^-1\";\n",
      "print\"The conductivity after doping with donor type impurity is =\",sigma1,\"(ohm-m)^-1\";\n",
      "print\"The conductivity after doping with acceptor type impurity is =\",sigma2,\"(ohm-m)^-1\";\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The intrinsic conductivity for silicon is = 0.000432 (ohm-m)^-1\n",
        "The conductivity after doping with donor type impurity is = 10.4 (ohm-m)^-1\n",
        "The conductivity after doping with acceptor type impurity is = 4.0 (ohm-m)^-1\n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.7 , Page no:274"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "ni=1E20; #in /m^3 (intrinsic carrier density)\n",
      "ND=1E21; #in /m^3 (donor impurity concentration)\n",
      "\n",
      "#calculate\n",
      "nh=ni**2/ND; #calculation of density of hole carriers at room temperature\n",
      "\n",
      "#result\n",
      "print\"The density of hole carriers at room temperature is nh=\",nh,\"/m^3\";\n",
      "#Note: answer in the book is wrong due to printing mistake"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The density of hole carriers at room temperature is nh= 1e+19 /m^3\n"
       ]
      }
     ],
     "prompt_number": 6
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.8 , Page no:275"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "M=72.6; #atomic mass of germanium\n",
      "P=5400; #in Kg/m^3 (density)\n",
      "ue=0.4; #in m^2/V-s (mobility of electrons)\n",
      "uh=0.2; #in m^2/V-s (mobility of holes)\n",
      "Eg=0.7; #in eV (Band gap)\n",
      "m=9.1E-31; #in Kg (mass of electron)\n",
      "k=1.38E-23; #in J/K (Boltzmann\u2019s constant)\n",
      "T=300; #in K (temperature)\n",
      "h=6.63E-34; #in J/s (Planck\u2019s constant)\n",
      "pi=3.14; #value of pi used in the solution\n",
      "e=1.6E-19; #in C(charge of electron)\n",
      "\n",
      "#calculate\n",
      "Eg=Eg*e; #changing unit from eV to J\n",
      "ni=2*(2*pi*m*k*T/h**2)**(3/2)*math.exp(-Eg/(2*k*T));\n",
      "sigma=ni*e*(ue+uh);\n",
      "\n",
      "#result\n",
      "print\"The intrinsic carrier density for germanium at 300K is ni=\",ni,\"/m^3\";\n",
      "print\"The conductivity of germanium is=\",round(sigma,3),\"(ohm-m)^-1\";\n",
      "print \"NOTE: The answer in the textbook is wrong\" "
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The intrinsic carrier density for germanium at 300K is ni= 3.33408559508e+19 /m^3\n",
        "The conductivity of germanium is= 3.201 (ohm-m)^-1\n",
        "NOTE: The answer in the textbook is wrong\n"
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.9 , Page no:275"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "rho1=4.5; #in ohm-m (resistivity at 20 degree Celcius)\n",
      "rho2=2.0; #in ohm-m (resistivity at 32 degree Celcius)\n",
      "k=1.38E-23; #in J/K (Boltzmann\u2019s constant)\n",
      "T1=20; T2=32; #in degree Celcius (two temperatures)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "\n",
      "#calculate\n",
      "T1=T1+273; #changing unit from degree Celius to K\n",
      "T2=T2+273; #changing unit from degree Celius to K\n",
      "#since sigma=e*u*C*T^(3/2)*exp(-Eg/(2*k*T))\n",
      "#therefore sigma1/sigma2=(T1/T2)^3/2*exp((-Eg/(2*k)*((1/T1)-(1/T2))\n",
      "#and sigma=1/rho \n",
      "#therefore we have rho2/rho1=(T1/T2)^3/2*exp((-Eg/(2*k)*((1/T1)-(1/T2))\n",
      "#re-arranging above equation for Eg, we get Eg=(2*k/((1/T1)-(1/T2)))*((3/2)*log(T1/T2)-log(rho2/rho1))\n",
      "Eg=(2*k/((1/T1)-(1/T2)))*((3/2)*math.log(T1/T2)-math.log(rho2/rho1));\n",
      "Eg1=Eg/e;#changing unit from J to eV\n",
      "\n",
      "#result\n",
      "print\"The energy band gap is Eg=\",Eg,\"J\";\n",
      "print\"\\t\\t\\t =\",round(Eg1,3),\"eV\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The energy band gap is Eg= 1.54302914521e-19 J\n",
        "\t\t\t = 0.964 eV\n"
       ]
      }
     ],
     "prompt_number": 8
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.10 , Page no:276"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "rho=2300; #in ohm-m (resistivity of pure silicon)\n",
      "ue=0.135; #in m^2/V-s (mobility of electron)\n",
      "uh=0.048; #in m^2/V-s (mobility of electron)\n",
      "Nd=1E19; #in /m^3 (doping concentration)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "\n",
      "#calculate\n",
      "#since sigma=ni*e*(ue+uh) and sigma=1/rho\n",
      "#therefore ni=1/(rho*e*(ue+uh))\n",
      "ni=1/(rho*e*(ue+uh)); #calculation of intrinsic concentration\n",
      "ne=Nd; #calculation of electron concentration\n",
      "nh=ni**2/Nd; #calculation of hole concentration\n",
      "sigma=ne*ue*e+nh*uh*e; #calculation of conductivity\n",
      "rho=1/sigma; #calculation of resistivity\n",
      "\n",
      "#result\n",
      "print\"The electron concentration is ne=\",ne,\"/m^3\";\n",
      "print\"The hole concentration is nh=\",nh,\"/m^3\";\n",
      "print\"The resistivity of the specimen  is =\",round(rho,3),\"ohm-m\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The electron concentration is ne= 1e+19 /m^3\n",
        "The hole concentration is nh= 2.20496745228e+13 /m^3\n",
        "The resistivity of the specimen  is = 4.63 ohm-m\n"
       ]
      }
     ],
     "prompt_number": 9
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.11 , Page no:276"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "uh=1900; #in cm^2/V-s (mobility of electron)\n",
      "Na=2E17; #in /m^3 (acceptor doping concentration)\n",
      "e=1.6E-19; #in C(charge of electron)\n",
      "\n",
      "#calculate\n",
      "uh=uh*1E-4; #changing unit from cm^2/V-s to m^2/V-s\n",
      "Na=Na*1E6; #changing unit from 1/cm^3 to 1/m^3\n",
      "nh=Na; #hole concentration \n",
      "#since sigma=ne*ue*e+nh*uh*e and nh>>ne\n",
      "#therefore sigma=nh*uh*e\n",
      "sigma=nh*uh*e; #calculation of conductivity\n",
      "\n",
      "#result\n",
      "print\"The conductivity of p-type Ge crystal is =\",sigma,\"/ohm-m   (roundoff error)\";\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The conductivity of p-type Ge crystal is = 6080.0 /ohm-m   (roundoff error)\n"
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.12 , Page no:277"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "ue=0.19; #in m^2/V-s (mobility of electron)\n",
      "T=300; #in K (temperature)\n",
      "k=1.38E-23; #in J/K (Boltzmann\u2019s constant)\n",
      "e=1.6E-19; #in C(charge of electron)\n",
      "\n",
      "#calculate\n",
      "Dn=ue*k*T/e; #calculation of diffusion co-efficient\n",
      "\n",
      "#result\n",
      "print\"The diffusion co-efficient of electron in silicon is Dn=\",Dn,\"m^2/s\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The diffusion co-efficient of electron in silicon is Dn= 0.00491625 m^2/s\n"
       ]
      }
     ],
     "prompt_number": 11
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.13 , Page no:277"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "Eg=0.4; #in eV (Band gap of semiconductor)\n",
      "k=1.38E-23; #in J/K (Boltzmann\u2019s constant)\n",
      "T1=0; #in degree Celcius (first temperature)\n",
      "T2=50; #in degree Celcius (second temperature)\n",
      "T3=100; #in degree Celcius (third temperature)\n",
      "e=1.602E-19; #in C (charge of electron)\n",
      "\n",
      "#calculate\n",
      "T1=T1+273; #changing temperature form Celcius to Kelvin\n",
      "T2=T2+273; #changing temperature form Celcius to Kelvin\n",
      "T3=T3+273; #changing temperature form Celcius to Kelvin\n",
      "Eg=Eg*e; #changing unit from eV to Joule\n",
      "#Using F_E=1/(1+exp(Eg/2*k*T))\n",
      "F_E1=1/(1+math.exp(Eg/(2*k*T1))); #calculation of probability of occupation of lowest level at 0 degree Celcius\n",
      "F_E2=1/(1+math.exp(Eg/(2*k*T2))); #calculation of probability of occupation of lowest level at 50 degree Celcius\n",
      "F_E3=1/(1+math.exp(Eg/(2*k*T3))); #calculation of probability of occupation of lowest level at 100 degree Celcius\n",
      "\n",
      "#result\n",
      "print\"The probability of occupation of lowest level in conduction band is\";\n",
      "print\"\\t at 0 degree Celcius, F_E=\",F_E1,\"eV\";\n",
      "print\"\\t at 50 degree Celcius, F_E=\",F_E2,\"eV\";\n",
      "print\"\\t at 100 degree Celcius, F_E=\",F_E3,\"eV\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The probability of occupation of lowest level in conduction band is\n",
        "\t at 0 degree Celcius, F_E= 0.000202505914236 eV\n",
        "\t at 50 degree Celcius, F_E= 0.000754992968827 eV\n",
        "\t at 100 degree Celcius, F_E= 0.00197639649915 eV\n"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.14 , Page no:278"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "Eg=1.2; #in eV (Energy band gap)\n",
      "k=1.38E-23; #in J/K (Boltzmann\u2019s constant)\n",
      "T1=600; T2=300; #in K (two temperatures)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "\n",
      "#calculate\n",
      "Eg=Eg*e; #changing unit from eV to Joule\n",
      "#since sigma is proportional to exp(-Eg/(2*k*T))\n",
      "#therefore ratio=sigma1/sigma2=exp(-Eg/(2*k*((1/T1)-(1/T2))));\n",
      "ratio= math.exp((-Eg/(2*k))*((1/T1)-(1/T2))); #calculation of ratio of conductivity at 600K and at 300K\n",
      "\n",
      "#result\n",
      "print\"The ratio of conductivity at 600K and at 300K is =\",ratio;"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The ratio of conductivity at 600K and at 300K is = 108467.17792\n"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.15 , Page no:278"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "ue=0.39; #in m^2/V-s (mobility of electron)\n",
      "n=5E13; #number of donor atoms\n",
      "ni=2.4E19; #in atoms/m^3 (intrinsic carrier density)\n",
      "l=10; #in mm (length of rod)\n",
      "a=1; #in mm (side of square cross-section)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "\n",
      "#calculate\n",
      "l=l*1E-3; #changing unit from mm to m\n",
      "a=a*1E-3; #changing unit from mm to m\n",
      "A=a**2; #calculation of cross-section area\n",
      "Nd=n/(l*A); #calculation of donor concentration\n",
      "ne=Nd; #calculation of electron density\n",
      "nh=ni**2/Nd; #calculation of hole density\n",
      "#since sigma=ne*e*ue+nh*e*ue and since ne>>nh\n",
      "#therefore sigma=ne*e*ue\n",
      "sigma=ne*e*ue; #calculation of conductivity\n",
      "rho=1/sigma; #calculation of resistivity\n",
      "R=rho*l/A; #calculation of resistance \n",
      "\n",
      "#result\n",
      "print\"The electron density is ne=\",ne,\"/m^3\";\n",
      "print\"The hole density is nh=\",nh,\"/m^3\";\n",
      "print\"The conductivity is =\",sigma,\"/ohm-m\";\n",
      "print\"The resistance is R=\",round(R),\"ohm\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The electron density is ne= 5e+21 /m^3\n",
        "The hole density is nh= 1.152e+17 /m^3\n",
        "The conductivity is = 312.0 /ohm-m\n",
        "The resistance is R= 32.0 ohm\n"
       ]
      }
     ],
     "prompt_number": 14
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.16 , Page no:279"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "RH=3.66E-4; #in m^3/C (Hall coefficient)\n",
      "rho=8.93E-3; #in ohm-m (resistivity)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "\n",
      "#calculate\n",
      "u=RH/rho; #calculation of mobility\n",
      "n=1/(RH*e); #calculation of density\n",
      "\n",
      "#result\n",
      "print\"The mobility is u=\",u,\"m^2/(V-s)\";\n",
      "print\"The density is n=\",n,\"/m^3\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The mobility is u= 0.0409854423292 m^2/(V-s)\n",
        "The density is n= 1.70765027322e+22 /m^3\n"
       ]
      }
     ],
     "prompt_number": 15
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 9.17 , Page no:279"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "from __future__ import division\n",
      "\n",
      "#given\n",
      "RH=3.66E-4; #in m^3/C (Hall coefficient)\n",
      "rho=8.93E-3; #in ohm-m (resistivity)\n",
      "e=1.6E-19; #in C (charge of electron)\n",
      "\n",
      "#calculate\n",
      "nh=1/(RH*e); #calculation of density of charge carrier\n",
      "uh=1/(rho*nh*e); #calculation of mobility of charge carrier\n",
      "\n",
      "#result\n",
      "print\"The density of charge carrier is nh=\",nh,\"/m^3\";\n",
      "print\"The mobility of charge carrier is uh=\",uh,\"m^2/(V-s)\";"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The density of charge carrier is nh= 1.70765027322e+22 /m^3\n",
        "The mobility of charge carrier is uh= 0.0409854423292 m^2/(V-s)\n"
       ]
      }
     ],
     "prompt_number": 16
    }
   ],
   "metadata": {}
  }
 ]
}