{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 4: p-n Junction" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 4.1, Page92" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "Na=10**18;#concentration\n", "Nd=10**15;#concentration\n", "N=9.65*10**9\n", "\n", "#calculation\n", "Vb=.0259*log(Na*Nd/N**2);#built in potential\n", "\n", "#result\n", "print\"built in potential is\",round(Vb,3),\"V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Populating the interactive namespace from numpy and matplotlib\n", "built in potential is 0.777 V\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example4.2 Page96" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "Na=10**19;#concentration\n", "Nd=10**16#concentration\n", "N=9.65*10**9\n", "q=1.6*10**-19#charge\n", "Es=10**-12;#constant\n", "\n", "#calculation\n", "Vb=.0259*log(Na*Nd/N**2);#voltage\n", "W=(2*Es*Vb/q/Nd)**.5;#width\n", "Em=q*W*Na/Es;#field\n", "\n", "#result\n", "print\"built in potential is\",round(Vb,3),\"V\"\n", "print\"depletion layer width is\",round(W*10**4,3),\"micro-m\"\n", "print\"maximum field at zero bias is\",round(Em/10299,0),\"V/cm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "built in potential is 0.896 V\n", "depletion layer width is 0.335 micro-m\n", "maximum field at zero bias is 5200.0 V/cm\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example4.3 Page 99" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "I=10**20;#impurity\n", "W=.50;#width\n", "q=1.6*10**-19;#charge\n", "E=8.85*10**-14#constant\n", "N=9.65*10**9;#concentration\n", "\n", "#calculation\n", "Em=q*I*W**2/(8*11.9*E);#maximum field\n", "Vb=.0259*I*W/N/2;#built-in voltage\n", "\n", "#result\n", "print\"maximum field is\",round(Em/10**8,0),\"V/cm\"\n", "print\"built-in voltage is\",round(Vb/10**8,2),\"V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "maximum field is 4748.0 V/cm\n", "built-in voltage is 0.67 V\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example4.4 Page101" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "Na=2*10**19;#concentration\n", "Nd=8*10**15;#concentration\n", "V=4.0;#voltage\n", "N=9.65*10**9\n", "q=1.6*10**-19;#charge\n", "E=10.53*10**-13#constant\n", "\n", "#calculation\n", "Vb=.0259*log(Na*Nd/N**2);#voltage at zero bias\n", "W1=(2*E*Vb/q/Nd)**.5;#width\n", "C1=E/W1;#capacitance at zero bias\n", "W2=(2*E*(Vb+V)/q/Nd)**.5;#width\n", "C2=E/W2;#capacitance at reverse bias\n", "\n", "#result\n", "print\"capacitance at zero bias is\",round(C1,11),\"F/cm^2\"\n", "print\"capacitance at reverse bias is\",round(C2,11),\"F/cm^2\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "capacitance at zero bias is 2.723e-08 F/cm^2\n", "capacitance at reverse bias is 1.172e-08 F/cm^2\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 4.5 Page109" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "Na=5*10**16;#concentration\n", "Nd=10**16;#concentration\n", "N=9.65*10**9\n", "Dn=21\n", "A=2*10**-4;#area\n", "Dp=10\n", "T=5*10**-7;#time\n", "q=1.6*10**-19;#charge\n", "\n", "#calculation\n", "J=q*(N**2)*(((Dp/T)**.5)/Nd +((Dn/T)**.5)/Na);#current density\n", "I=A*J;#ideal reverse current\n", "\n", "#result\n", "print\"ideal reverse current is\",round(I,17),\"A\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "ideal reverse current is 1.72e-15 A\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example4.6 Page110" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "Na=5*10**16;#concentration\n", "Nd=10**16;#concentration\n", "N=9.65*10**9\n", "V=4;#voltage\n", "E=10.53*10**-13;#constant\n", "T=5*10**-7;#time\n", "q=1.6*10**-19;#charge\n", "\n", "#calculation\n", "W=(2*E*(Na+Nd)/(q*Na*Nd)*(.0259*log(Na*Nd/N**2)+V))**.5;#width\n", "J=q*N*W/T;#current density\n", "\n", "#result\n", "print\"generation current density is\",round(J,9),\"A/cm^2\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "generation current density is 2.68e-07 A/cm^2\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 4.7 Page115" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "Nd=8*10**15;#concentration\n", "V=1.00;#voltage\n", "L=5*10**-4;#length of holes\n", "q=1.6*10**-19;#charge\n", "N=9.65*10**9\n", "\n", "#calculation\n", "Q=q*L*N**2/Nd*(e**(1/.0259)-1);#minority carriers\n", "\n", "#result\n", "print\"stored minority carriers is\",round(Q,2),\"C/cm^2\"\n", "print\"the answer in book is slightly wrong\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "stored minority carriers is 0.05 C/cm^2\n", "the answer in book is slightly wrong\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example4.8, Page120" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "Nd=5*10**16;#concentration\n", "E=10.53*10**-13;#constant\n", "N=5.7*10**5\n", "q=1.6*10**-19;#charge\n", "\n", "#calculation\n", "Vb=E*N**2/2/q/Nd;#breakdown voltage\n", "\n", "#result\n", "print\"breakdown voltage is\",round(Vb,1),\"V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "breakdown voltage is 21.4 V\n" ] } ], "prompt_number": 34 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example4.9 Page122" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "Nb=8*10**14;#concentration\n", "E=8.85*10**-14;#constant\n", "q=1.6*10**-19;#charge\n", "V=500;#voltage\n", "W=20*10**-4;#width\n", "\n", "#calculation\n", "Wm=(24.8*E*V/q/Nb)**.5;#width\n", "Vb=V*(W/Wm)*(2-(W/Wm));#breakdown voltage\n", "\n", "#result\n", "print\"width is\",round(Wm*10**4,1),\"micro-m\"\n", "print\"breakdown voltage is\",round(Vb,3),\"V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "width is 29.3 micro-m\n", "breakdown voltage is 449.771 V\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example4.10 Page126" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variable\n", "from math import *\n", "V=1.60;#voltage\n", "C1=10**16;#concentration\n", "C2=3*10**19;#concentration\n", "D1=12.00;#dielectric constant\n", "D2=13.00;#dielectric constant\n", "E=8.85*10**-14;#constant\n", "q=1.6*10**-19;#charge\n", "\n", "#calculation\n", "V1=D2*C2*V/(D1*C1+D2*C2);#voltage\n", "V2=D1*C1*V/(D1*C1+D2*C2);#voltage\n", "W1=(2*D1*D2*E*C2*V/(C1*D1+C2*D2)/q/C1)**.5;#depletion width\n", "W2=(2*D1*D2*E*C1*V/(C1*D1+C2*D2)/q/C2)**.5;#depletion width\n", "\n", "#result\n", "print\"electrostatic potential 1 is\",round(V1,2),\"V\"\n", "print\"electrostatic potential 2 is\",round(V2,5),\"V\"\n", "print\"depletion width 1 is\",round(W1,8),\"cm\"\n", "print\"depletion width 2 is\",round(W2,11),\"cm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "electrostatic potential 1 is 1.6 V\n", "electrostatic potential 2 is 0.00049 V\n", "depletion width 1 is 4.608e-05 cm\n", "depletion width 2 is 1.536e-08 cm\n" ] } ], "prompt_number": 11 } ], "metadata": {} } ] }