{ "metadata": { "name": "CH18" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 18 : Electrical Properties" ] }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 18.1 Page No 682" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "sigma=10**-6 # (Ohm-m)**-1 Electrical Conductivity\n", "e=1.6*10**-19 #Coulomb Charge on electron\n", "m_e=0.85 # m**2/V-s Mobility of electron\n", "m_h=0.04 # m**2/V-s Mobility of holes\n", "\n", "ni=sigma/(e*(m_e+m_h))\n", "\n", "print\"Intrinsic Carrier Concentration is\",round(ni,-11),\"m**-3\"\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Intrinsic Carrier Concentration is 7e+12 m**-3\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 18.2 Page No 689" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "e=1.6*10**-19 #Coulomb Charge on electron\n", "ni=4*10**19 #For Si at 423 K (m**-3)\n", "m_e=0.06 #m**2/V-s Mobility of electron\n", "m_h=0.022 #m**2/V-s Mobility of holes\n", "\n", "sigma=ni*e*(m_e+m_h)\n", "\n", "print\"Electrical Conductivity is \",round(sigma,2),\"(ohm-m)**-1\"\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Electrical Conductivity is 0.52 (ohm-m)**-1\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 18.3 Page No 690" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "n=10**23 #m**-3 Carrier Concentration\n", "e=1.6*10**-19 #Coulomb Charge on electron\n", "m_e=0.07 #m**2/V-s Mobility of electron\n", "\n", "sigma=n*e*m_e\n", "\n", "\n", "m_e2=0.04 #m**2/V-s Mobility of electron\n", "sigma2=n*e*m_e2\n", "\n", "print\"Conductivity at n=10**23 is \",sigma,\"(Ohm-m)**-1\"\n", "print\"Conductivity at T=373 K becomes \",sigma2,\"(Ohm-m)**-1\"\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Conductivity at n=10**23 is 1120.0 (Ohm-m)**-1\n", "Conductivity at T=373 K becomes 640.0 (Ohm-m)**-1\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Design Example 18.1, Page No: 691" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "c=50 #ohm**-1, room temprature conductivity\n", "Na1=10**22 #m**-3, assumed impurity content value\n", "mu1=0.04 #m**2/Vs, assumed electrical mobility\n", "e=1.6*10**-19 #Electronic charge\n", "NA=6.023*10**23 #Avagadro no\n", "\n", "C=Na1*e*mu1 #Conductivity\n", "Na2=10**21 #m**-3, \n", "mu2=0.045 #m**2/Vs,\n", "C=Na2*e*mu2\n", "Na=8*10**21 \n", "rho=2.33 # g/cm**3\n", "Asi=28.09 # g/mole\n", "Nsi=(NA*rho*10**6)/(Asi)\n", "Ca=(Na/(Na+Nsi))*100\n", "\n", "print\"The concentration of acceptor impurities is\",round(Ca,7)\n", "print\"Thus a Silicon material having conductivity 50 ohm**-1 \\nmust contain\",round(Ca,7),\"% boron,aluminium,Gallium or indium .\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The concentration of acceptor impurities is 1.6e-05\n", "Thus a Silicon material having conductivity 50 ohm**-1 \n", "must contain 1.6e-05 % boron,aluminium,Gallium or indium \n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 18.4 Page No 693" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "sigma=3.8*10**7 #(Ohm-m)**-1 Electrical Conductivity\n", "m_e=0.0012 #m**2/V-s Mobility of electron\n", "Rh=-m_e/sigma #Hall coefficient\n", "Ix=25 #Ampere(A) Current\n", "d=15*10**-3 #m Thickness\n", "Bz=0.6 #Tesla Magnetic field\n", "\n", "Vh=Rh*Ix*Bz/d\n", "\n", "print\"Hall coefficient is \",round(Rh,13),\"V-m/A-Tesla\"\n", "print\"Hall Voltage is \",round(Vh,10),\"V\"\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Hall coefficient is -3.16e-11 V-m/A-Tesla\n", "Hall Voltage is -3.16e-08 V\n" ] } ], "prompt_number": 13 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 18.5 Page No 707" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "A=6.45*10**-4 #m**2, area\n", "d=2*10**-3 #m. Plate separation\n", "V=10 #V Potential\n", "Er=6 #Dielectric constant\n", "Eo=8.85*10**-12 #F/m Constant dielectric constant\n", "E=Er*Eo\n", "C=E*A/d\n", "Q=C*V\n", "D=E*V/d\n", "P=D-Eo*V/d\n", "\n", "print\"The Capacitance is\",round(C,13),\"F\"\n", "print\"The magnitude of charge stored is \",round(Q,12),\"C\"\n", "print\"The Dielectric displacement is is\",round(D,9),\"C/m**2\"\n", "print\"The Polarization is\",round(P,9),\"C/m**2\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The Capacitance is 1.71e-11 F\n", "The magnitude of charge stored is 1.71e-10 C\n", "The Dielectric displacement is is 2.65e-07 C/m**2\n", "The Polarization is 2.21e-07 C/m**2\n" ] } ], "prompt_number": 15 }, { "cell_type": "code", "collapsed": false, "input": [], "language": "python", "metadata": {}, "outputs": [] } ], "metadata": {} } ] }