电子信息类专业英语(李白萍).ppt

UnitNineMicroelectronics PassageAIntroductiontoMicroelectronicsPassageBTheSimpleAtom Conductors InsulatorsandSemiconductorsPassageCDiodeandTransistor PassageAIntroductiontoMicroelectronicsTheexploringofspaceandthedevelopmentofearthsatelliteshasincreasedtheimportanceofreducingthesizeandweightofelectroniccircuits Also eventhoughelectricityflowsquiterapidlyincomputersthetimedelayofthesignalintheinterconnectionsbetweenelectroniccomponentsisanimportantconsideration Iftheinterconnectionsarereducedinsize acomputercanperformoperationsatafasterspeed Microelectronicsinvolvestheminiaturizationofregularelectroniccircuits Acompleteelectroniccircuit anoperationalamplifierforexample whichcontainslargenumbersofindividualinterconnectedcomponents suchasdiodesresistors transistors etc maybeformedonaverysmallsinglesubstrate Thecompleteminiaturizedcircuitisthencalledanintegratedcircuit Integratedcircuitsaresmall light rugged andreliable Theyrequirelesspowerandlowervoltagesthanequivalentmacroscopiccircuits consequentlytheyoperateatlowertemperatures andindividualcomponentsmaybeclosetogetherwithoutexceedingtheoperatingtemperaturelimit RelativelylittlestraycapacitanceandshorttimedelaysareproducedbecauseoftheshortinterconnectionsbetweentheindividualcomponentsinIC MaintenanceissimplifiedbecauseifacomponentoftheICfailsthecompleteICisusuallyreplaced MassproductiontechniquesofplanetechnologyhavereducedthecostofmanyICsothattheyarealmostasinexpensiveasasingletransistor EventuallymostconventionalcircuitswillbereplacedbyIC Therearetwotypesofbasicintegratedcircuit monolithicintegratedcircuitandthethinorthickfilm MonolithicICareconstructedinasinglesubstrateofsinglecrystalsemiconductor usuallysilicon ThinorthickfilmsICareformedonthesurfaceofaninsulatingmaterialsuchasglassoraceramic HybridICcontainsmorethanasinglesubstrate thetermhybridisalsoappliedtocombinationsofmonolithicandthinorthickfilmIC Integratedcircuitsarealsoclassifiedaccordingtotheirfunctions DigitalorlogicalICareusedasswitches theyareeitheronoroff Incomputerstheonandoffstatescorrespondto0or1 OtherICiscalledlinearoranalogIC 1 Integratedcircuitscanbeproducedusingeitherbipolaroruniquepolartransistors Fieldeffecttransistors FET haveaadvantagesoverbipolartransistorsinmanycaseshowever Theyarerelativelyhigh impedancedevices withacorrespondingreductionincurrentandpowerdissipation andyethavehighpowergain Thereductioninpowerdissipationisparticularlyimportantwhereacomplexcircuitistobeconcentratedintoasmallspace Theproblemofextractingtheheatgeneratedinthecircuitmaythenbeadifficultone 2 TheformofconstructionoftheFET andparticularlytheMOSFET alsolendsitselfwelltointegratedcircuitfabrication andenablesresistorsandcapacitorstobeincludedreadilyintheintegratedcircuit Mostelectroniccircuitsarecomposedofactivedevices e g transistorsanddiodes togetherwithresistors forbias collectorload impedancetransformation etc andcapacitors e g forcouplingacsignalswhileblockingdcsupplies Eachoftheseelementscanbeproducedinaformsuitableforintegratedcircuitinclusionwithinlimitations e g capacitancevaluesmustnotbetoolarge Someelementsaredifficulttoproduceinasuitableform e g inductiveelements orlargecapacitors Usuallysomealternativecircuitformcanbedevisedthatdispenseswiththerequirement Otherwisetheymustbeincludedasanexternallumpedelement KEYWORDSmicroelectronic微电子amplifier放大器considerable相当的 重要的substrate基质 底质integrate综合 使完全rug地毯 毯子reliable可靠maintenance维护 保持 维修film胶片 薄膜monolithic独立的 完全统一的silicon硅hybrid混合物bipolar 电子 双极的 FET Fieldeffecttransistors 场效应管impedance阻抗dissipation损耗extractive抽出 释放出fabrication制造 装配 捏造事实bias偏差 偏置capacitor电容inductive电感dispense分配lumpedelement集总元件transistor晶体管 NOTES 1 Integratedcircuitsarealsoclassifiedaccordingtotheirfunctions DigitalorlogicalICareusedasswitches theyareeitheronoroff Incomputerstheonandoffstatescorrespondto0or1 OtherICiscalledlinearoranalogIC 也可根据其功能不同对集成电路进行分类 数字IC 也称为逻辑IC 通常用作开关 表示接通或关断 在计算中 接通和关断状态分别对应 0 或 1 另一种IC被称为线性或模拟IC either or 表示两者择一 在文中译为 要么 要么 2 Thereductioninpowerdissipationisparticularlyimportantwhereacomplexcircuitistobeconcentratedintoasmallspace Theproblemofextractingtheheatgeneratedinthecircuitmaythenbeadifficultone 减小功率损耗是非常重要的 其方法是将一个复杂的电子线路集成为一小块 这使得释放电路工作时产生的热量变成一个难题 Theproblemof maythenbeadifficultone 文中的one表示强调这个问题 这种句式在科技英语中常被使用 extractingtheheat为释放热量的意思 extract的本意为 抽出 剥离 在电子线路中 器件工作均会产生热量 如果不能及时散热 器件就不能稳定工作 PassageBTheSimpleAtom Conductors InsulatorsandSemiconductorsTheSimpleAtomThematerialsthatmakeupouruniversearecomposedofoveronehundredbasicandindividualtypesofmattercalledelements Ninety twooftheseelementsoccurnaturallyandtheremaindersareman made Eachelementhasaseparateidentifyofitsown thatis notwoelementshavethesamephysicalandchemicalproperties norcananelementbesubdividedbyordinaryphysicalandchemicalmeansintosimpleelements 1 Examplesofelementsaregold mercuryandoxygen Elementscontainsmallerparticlescalledatoms Inanyoneelementtheatomsareidenticalinstructure Thedifferencebetweenanytwoelementssuchasgoldandmercuryisintheiratomicstructures Theyhaveincommon however arelativelyheavyinnercorecalledanucleussurroundedbyoneormoreextremelylightparticlesofmattercalledelectrons Thesimplestnucleusisamassofmatterabout2 000timestheweightofanelectron andiscalledaproton Morecomplexnucleicontainvariouscombinationsofprotonsandneutrons Aneutronisaprotoncombinedwithanelectronandiselectronicallyneutral Electronswhirlaroundnucleiinmuchthesamemannerthattheplanetsofoursolarsystemtravelaroundthesun Thedifferencebetweenanatomofoneelementandthatofanotherisinthenumberofprotonsandneutronscontainedinthenucleus 2 Alltheelementsintheuniverse andthereforeallmatter iscomposedofprotons neutrons andelectrons Theremustbeforceofattractionbetweenanucleusandtheelectronssurroundingit otherwisetheelectronswouldflyoffintospace inordertounderstanditsnature wefindithelpfultocallthisforceacharge Thechargeofthenucleusisdefinedaspositive andtheoppositechargeoftheelectron negative Inviewofthefactthatoppositesattract theforcebetweenthenucleusandtherotatingelectronarounditpreventstheelectronfromflyingoffintospace Anatom whichhasallofitsorbital rotating electronshasasmanypositivechargesandthereforethenetchargeiszero Whenanatomlosesanelectronthebalanceofchargeisdisturbedandtheatombecomespositivelycharged Inthiscondition theatomiscalledapositiveion Incomparison whenanatomacquiresanelectron thebalanceofchargesisagaindisturbedandtheatombecomesnegativelycharged suchanatomisreferredtoasanegativeion Conductors InsulatorsandSemiconductorsAnysubstance whichallowselectronstoflowfreelythroughitsstructureiscalledaconductor Ingeneral metalsaregoodconductors Adefiniterelationshipexistsbetweengoodconductorsandtheiratomicstructures Ingoodconductors theouter ringelectrons whicharealsocalledvalenceelectrons maybereleasedfromtheirorbitswithrelativeease Atomwith1 2and3outerringelectrons andthereforemostmetalsaregoodconductors Substance whichpreventthepassageofelectronsthroughtheirstructuresarecalledinsulators Insulatorshaveveryfeweasilyremovedelectronsintheirouterrings Therearenoperfectinsulators first becauseofthepresenceofimpurities foreignmaterials whichcanneverbeentirelyremoved andsecond becauseevenasmallamountofheatwillcauseacertainnumberofvalenceelectronstobefreedfromtheiratoms Insulatorsgenerallyhaveverystableatomicstructures ofwhichthe4 electronouter ringstructureistypical Insuchastructure thereisanabsenceofeasilyremovedelectrons Exampleofgoodinsulatorsarecertaincompoundsofcarbon abasicingredientofrubber anddiamond whichhasasimilaratomicstructure Semiconductorsareagroupofmaterials whichconductelectronspoorlyandthereforecannotproperlybeclassifiedeitherasconductorsorinsulators Generally semiconductorsdifferfrominsulatorsinthattheirouter ringelectronscandetachthemselvesfromtheirorbitsmoreeasilythanininsulators Typicalsemiconductorsmaterialsaregermaniumandsilicon Impuritiesmaybeaddedtopuresemiconductors Thisresultsinsemiconductormaterials whichmayeitherhaveanexcessoffreeelectronsoradeficiencyoforbitalelectrons WhenanexcessofelectronsispresentwecallthematerialN type whenlackoforbitalelectronsoccurs wecallthematerialP type BothN typeandP typesemiconductorsaremadebytreatedmaterials suchasgermaniumandsiliconwithimpuritiessuchasarsenicandindium 3 Theadditionofimpuritiestosemiconductorsiscalleddoping KEYWORDSnaturally自然的 天生具备identity标识 标志mercury汞 金属的一种oxygen氧气 氧元素nucleus原子核proton质子neutrons中子force力量 力charge主管 看管 承载orbital眼眶 轨道positive正电negative负电 conductor导体semiconductor半导体insulator绝缘vale