{ "metadata": { "name": "", "signature": "sha256:a04d8bca9534fb9597d80a980e2f1b54e0ff54b9697a6bc1d33eb2c967636be8" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter7:TRANSFERRED ELECTRON DEVICES(TEDs)" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg7.2.1:pg-294" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the conductivity of the diode\n", "e=1.6*(10**-19) #charge of electron in C\n", "nl=(10**10)*(10**6) #electron density at lower valley in /m**3\n", "nu=(10**8)*(10**6) #electron density at upper valley in /m**3\n", "ul=8000*(10**-4) #electron mobility at lower valley in m2/V-sec\n", "uu=180*(10**-4) #electron mobility at upper valley in m2/V-sec\n", "o=e*((nl*ul)+(nu*uu)) \n", "o=o*1000 #in milli mhos\n", "print\"The conductivity of the diode(in mmhos)is=\",round(o,2),\"mmhos\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the conductivity of the diode(in mmhos)is= 1.28 mmhos\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg7.2.2:pg-298" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#(a)Calculate the electron drift velocity\n", "q=1.6*(10**-19) #charge of electron in C\n", "f=10*(10**9) #operating frequency in Hertz\n", "L=10*(10**-6) #Device Length in meter\n", "vd=f*L \n", "print\"The electron drift velocity is =\",\"{:.0e}\".format(vd),\"m/s\",\"{:.0e}\".format(vd*100),\"cm/s\"\n", "\n", "#(b)Calculate the current density\n", "n=2*(10**14)*(10**6) \n", "J=q*n*vd \n", "print\"The current density is =\",\"{:.1e}\".format(J),\"A/m2 =\",int(round(J/(10**4))),\"A/cm2\"\n", "\n", "#(c)CAPTION: Calculate the negative electron mobility\n", "E=3200 #applied field\n", "vd=vd*(100) #in cm/sec\n", "un=-1*vd/E \n", "print\"Negative electron mobility(in cm**2/V*sec) is =\",int(round(un)),\"cm2/V.s\" #answer is wrong in book " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The electron drift velocity is = 1e+05 m/s 1e+07 cm/s\n", "The current density is = 3.2e+06 A/m2 = 320 A/cm2\n", "Negative electron mobility(in cm**2/V*sec) is = -3125 cm2/V.s\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg7.3.1:pg-304" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the criteria for classifying the modes of operation\n", "er=13.1 #relative dielectric constant\n", "vd=2.5*(10**5) #electron drift velocity in m/sec\n", "e=1.6*(10**-19) #charge of electron in C\n", "E=8.854*(10**-12)*er #permittivity of GaAs in F/m\n", "un=-0.015 #negative electron mobility in m**2/v.s\n", "un=-1*un\n", "a=(E*vd)/(e*un)\n", "print\"The criteria is=\",\"{:.3e}\".format(a),\"/m2 =\",\"{:.3e}\".format(a/10000),\"/cm2\" #calculation mistake in book \n", "print\"This means that the product of doping concentration and the device length must be\"\n", "print\"noL >\",\"{:.3e}\".format(a/10000),\"/cm2\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The criteria is= 1.208e+16 /m2 = 1.208e+12 /cm2\n", "This means that the product of doping concentration and the device length must be\n", "noL > 1.208e+12 /cm2\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg7.4.1:pg-311" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the output power\n", "n=0.06 #conversion efficiency\n", "M=3.5 #Multiplication factor\n", "Eth=320*(10**3) #threshold field in V/m\n", "L=12*(10**-6) #Device Length in m\n", "n0=10**21 #Donor concentration in m**3\n", "e=1.6*(10**-19) #charge of electron in C\n", "v0=1.5*(10**5) #Average carrier velocity in m/sec\n", "A=3*(10**-8) #Area m**2\n", "p=n*(M*Eth*L)*(n0*e*v0*A) \n", "p=p*1000 # in mW\n", "print\"The output power(in mW)is=\",int(round(p)),\"mW\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The output power(in mW)is= 581 mW\n" ] } ], "prompt_number": 5 } ], "metadata": {} } ] }