----Semiconductors2DinInstabilitiesandResistanceDifferentialNegative
VickersJ.A.andRidley,K.B.Balkan,N.byed.[Physics]SeriesASINATO 307B 1993)York(NewPressPlenum53-82,pp.,
TRANSFERSPACEREALONBASEDDEVICESLOGICEMITTINGLIGHTHETEROSTRUCTURESInGaAs/InAlAsCOMPLEMENTARYIN
MastrapasquaMarcoandLuryiSerge
LaboratoriesBellAT&T07974NJHill,Murray
ABSTRACT
deviceslogiclight-emittingnovelofimplementationtheandprinciplethediscussWeconductingcomplementarybetweenelectronshotof(RST)transferreal-spacetheonbased
dopedisemitter,thelayers,theseofOnelayers. n forcontactsmoreortwohasand-typeaintoinjectedareelectronsfield,thisbyHeatedfield.electriclateraltheapplying
complementary p iscurrentinjectionTheindependently.contactedlayer,collector-typetransferredtheofrecombinationthefromarisingsignalluminescenceabyaccompanied
region.activecollectordesignedspeciallyainelectronsfunctionalimplementtooneenablesRSTbyinjectionchargeofsymmetrypeculiarThe
theingateORexclusiveanasactscontactsemittertwowithstructuresimplestThegates.logicThevoltages.inputtheonlightoutputtheandcurrentcollectorthebothofdependence
electricallyisandNANDandORasfunctionssuchperformsdevicemultiterminalatdemonstratedareoperationslogicpowerfulThesefunctions.thesebetweenreprogrammable
temperature.roomtransistors.RSTofpropertiessymmetrytheofstudiestheoreticalrecentreviewalsoWe
varietyarevealsimulation,devicetransientandmodelingcontinuationonbasedstudies,Theseofnoveltystrikingaandinstabilitiesof multiply-connected RSTAcharacteristics.current-voltage
theinoccursinjectionhot-electronwhichinstatessteadyanomaloussupportcantransistorreflectionthebreakstatestheseofSomeelectrodes.emitterthebetweenvoltageanyofabsence
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INTRODUCTION1.
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configurations:biasexternaldifferent
S [ V D , V C ] →← S [ − V D (, V C − V D ]) . (1)
----
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----
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|0.0
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| | | | |
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----
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| | | | |
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----
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|0
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|2
|3
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||
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|| | | | | |
||
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----
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----
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|50
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________________________________________________________________________________________________
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________________________________________________________________________________________________
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statethatindicatesThis d oframpingrapidinfoundfirsthadwe(which V C at V D = 0,ofvariationquasi-staticabyaccessibleexperimentallyis20)Fig.cf. V D fixedat V C The.
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24Fig. fourtheinpotentialchannelThe.atstatesanomalous V D = 0.
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25Fig. statesnon-stationarytheofEvolution. c+ andlines)(solid c− atlines)(dashed V D = .0inshowniscurrentinjectiontheofdependenceTime figureleftthe selectedthemarksymbols;
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nearalreadyexistsdomainhot-electronfully-developeda D thenearyetnotbut S electrode.
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theinNDRawith I C (V C) dependence, ∂I C⁄∂V C < 0 ofthatand, b bothwith ∂I C⁄∂V C < 0and ∂I D⁄∂V D < 0 found.beenyethasrulethistocounterexampleNo.
characteristics.current-voltageCHINTofmappingsDC shows26Fig. I D (V DS)atdevicesingleaforcharacteristics T = 300 voltagescollectorfixedofseriesausingK
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Atconnected.singlyremaincurves V CS ∼∼ 1.2 inappeartobeginsloopdisconnectedaV,minimumabyboundedsurfaceatocorrespondingplane,left-handthe V CS 3Dthein
(27Fig.inshownAs26.Fig.inspace V CS = 1.5 needle-liketheandloopclosedthisV),theandopen,tocontinuebothplaneleft-handtheofbottomthefromemanatingfold
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componentconnectedsinglyaandorigin,theincludeswhichloopaintotransformedtwoTheseloop.thewithintersectionsorfoldsnohasbutmultivaluediswhich
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VDS (Volts) VCS(Volts)
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26Fig. CHINT: I D-V DS forcharacteristics1.0V ≤ V CS ≤ (2.0V L CH = 5µm, d B = 0.2µm,v sat = 1×107cm⁄ representCurvess).
constantatsimulations V CS byseparated∆V CS = 0.1V.
anomalousofmultiplicitytheNote V DS = 0 atgeneral,Instates. V DS = 0 canwe,numberoddanexpect m S numberevenanandstatessymmetricof m A asymmetricof
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(withcasesrealizetoablebeen m S, m A) = 4)(5,and4),(3,2),(3,,0)(3,,0)(1, aIn.ofvariationcontinuous V CS thewhensituationaatarrivecourse,ofcan,one I D (V DS)
thetouchesonlycurve V DS = 0 anistherepointsingularthisAtcrossing.withoutaxisdistinctofnumbertotaltheandstates,symmetrictwoofdegeneracyaccidental
even.becomesstatessymmetricdisconnectedtopologicallytobelongmaypartnerssymmetrytheInterestingly
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origin.thefromdisconnectedloop,theoftheofmapashows28Figure I C-V DS thetocorresponding, I D-V DS 27.Figs.inplot
sincestatedevicethedefinecompletelytheyTogether, I C = I S + I D ofslicesAlthough.I C-V DS givenaforspace V CS space,3Dtheinsymmetryistheresymmetric,notare
symmetrytheunderinvariantiscurrentcollectortheSince(1).Eq.byexpressedofplotstransformation, I C-V DS definedPoints28.Fig.cf.self-intersections,manyhave
thewithintersectionsingleaby V DS = 0 statessymmetrictocorrespondaxis( I C = 2 I D = 2 I S reflective,representintersectionscoincidenttwobydefinedpoints);
pairs.asymmetric
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27Fig. CHINTSingle: I D-V DS characteristicfor26Fig.from V CS = whichV1.50
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have28,and27Figs.incurvesbyrepresentedthoselikemappings,spacePhasecloseinfinitesimallytheirself-intersections,ofvicinitytheinexceptthatpropertythe
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aondistancefiniteabyseparatedpointstrue:alwaysisconverseThe (V , I ) planestatesdistinctmacroscopicallytocorrespond z pseudo-arclengththeinContinuation.
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k→u as22,Figs.in V DS orformationthetocorresponding0,fromincreasedisnegativeresultantThedomain.high-temperaturehigh-field,aofrepositioning I D at u
toduedrain,theofthatthanlowerisdomainelectronhottheinpotentialtheasarisesfield.collectorunscreenedthe
fororiginthefromstartedsimulationscontinuationofresultstheshows29Fig.V DS > 0 velocitysaturationhigherausing, vsat theBoth. V CS and V DS forthresholds
inpointslimitorfoldscausing IV withincrease vsat forreducedarethresholdsThe.smaller L CH inabovedescribedthosetosimilararedependenciesThese30.Fig.see,
transientaofspeedrampcriticalthewithconnection V CS inducetorequiredexcitationstablethe d atstate V DS = 0.
artificialsomewhattheofspiteIn v (F ) and T e(F ) canitsimulation,theinassumedRSTthepastobservedstepsnonlineartheofcausethethatconcludedsafelybe
Transientcontinuation.bypredictedfoldsandloopstheareexperimentsinthreshold29Fig.in(e.g.foldsthatindicateproceduresmeasurementtocorrespondingsimulations
for V CS = 3.0 transitionstatethewhereofPredictionslength.sometofollowedbecanV)dccompletefromaccuratelyextractedbecanoccurwill IV mustanalysisthisbutmaps,
circuitexternalaswellasterminalsallateffectsNDRofconsiderationincludeconfigurations.†
________________
ofcontinuitytheforbasisphysicaltheiswhatunderstandtointerestingverybewouldIt† W tot notedfootnotetheand13bFig.seecharacteristics,CHINTexperimentalintransitionsmanyatempirically
(6).Eq.below
----
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|0.1
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VCS=2.00V
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|0.0
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|2.0
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|-0.05
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29Fig. CHINT: I D-V DS aascharacteristicsoffunction V CS (L CH = 5 µm, d B = 0.2 µm,
v sat = 2 × 107 cm⁄ onlyshownareResultss).thefor V DS > thefrominitiatedbranches0
origin.
30Fig. CHINT: I D-V DS aascharacteristicsoffunction V CS (L CH = 2 µm, d B = 0.2 µm,
v sat = 1 × 107 cm⁄ onlyshownareResultss).thefor V DS > thefrominitiatedbranches0
origin.
ResultsSimulationtheofSummary6.3
complicatedpossesstransistorsinjectionchargeThe – multiply-connectedoften –IV highsufficientlyaofApplicationcharacteristics. V DS fixedaat V CS > 0 aforces
domain.electronhotaofformationthebyaccompaniedtransition,switchingatoelectronsofratesupplyfinitethewhenformdomainsthePhysically, " spothot " is
fringingtheunscreendomainsdepletedThespot.thatfromfluxRSTthebyexceeded(field "normally" collectorbecomesRSTtheandelectrons)channelbyscreened
controlled.peculiartheironbasedbetolikelyaredevicesRSTofapplicationsPotential
inupshowssymmetrysameThepolarity.fieldheatingthetorespectwithsymmetrydeviceRSTmultiterminalaofStatesformation.domainhot-electrontheofanalysisthe
arebiasgeneralunder "adiabatically" theofstatesanomalousthetoconnectedatconfigurationsymmetric V D = 0 potentveryprovetolikelyisanalysissymmetryThe.
2b,Fig.ofgateORNANDtheassuchgeometry,complicatedmoreofdeviceswithisgroupsymmetrywhose C 3 v atoccurthatPhenomena. V DS = 0 essentialthecapture
general.indomainsRSTthewithassociatedphysicsmodeltransportausingoutcarriedbeenhaveabovedescribedsimulationsThe
mobilitydifferentialnegativeafromresultinginstabilitiesusualtheeliminateswhichverifiedbeenhaveresultsTheexcluded).artificiallybeenhaslatter(the 23 remainto
InGaAs.forappropriatemodelvelocity-fieldrealisticmoreawithvalidqualitatively2,Fig.inthoselikestructure,deviceRSTparticularaofsimulationquantitativeaFor
anomaliesnoveltheHowever,model.transportrealisticaneedclearlywouldoneinreproducedqualitativelybecan6,Sect.indiscussed any channelallowsthatmodel
flux.RSTtheincludesself-consistentlyandheatedbetoelectronsmethodscontinuationofusetheisanalysisabovetheoffeatureessentialAn
theSlicingspace.phasedevicefulltheofinspectiontheallowwhich I D (V D, V C) surfacedifferentat V C inresults I D (V D) evolvefieldsinternalThetopologies.differentofcurves
connectedaalongsmoothly I D (V D) aofapproachthesignalnotdoandtrajectoryoftypeglobalthegivesuccessfullymappingsPhase-spacetransition.switching
thetoasguessunerringangiveusuallytheyMoreover,information. stability givenaofunderstandingThesimulations.transientcostlierbysupportedsubsequentlystate,
thetotransistorsRSTofapplicationtheininvaluablebewillfashionthisingainedsystems.high-performanceofdesign
----
CONCLUSION7.
leight-emittingnovelofimplementationtheandprinciplethediscussedhaveWeindependentlybetweenhot-electronsoftransferreal-spacetheonbaseddevices,logic
thatdevice,logicmultiterminalmonolithicAlayers.complementarycontactedThedescribed.beenhasgate,ORNANDanaselectricallyandopticallybothfunctions
thebothexhibitsheterostructure,InGaAs/InAlAs/InGaAsaninimplementeddevice, ortheand nand outputtheeitherinterminals.inputthreetheoftwoanyoffunctions
arebutlayoutthebyfixednotarefunctionsThesepower.outputopticaltheorcurrent(thirdtheonvoltagethebyinterchangeable "control" controltheofChoiceterminal.)
powerfulsuchwithdevicelogicuniqueaisThisarbitrary.moreover,is,electrodecircuitaofcoursetheinreprogrammableelectricallyisfunctionitscapabilities;
operation.thansmallermuchisdiscontinuitybandvalencetheusedheterostructuretheIn
thetodueiscurrentnon-RSTparasitictheofmostandbandconductiontheinthatthefromholesofinjection p theintolayercollector-type n atoDueemitter.-type
activetheconfininglayerInAlAswide-gapawithstructurecollectordesignedspeciallyhighermuchiscollectortheincarriersminorityofefficiencyradiativethelayer,InGaAs
andnon-radiativerelativelycurrentleakagethemakesThisemitter.theinthatthantemperature.roomatperformancelogicopticaltheenhancessubstantially
atosimilarsource,light-emittingincoherentanisdevicedemonstratedThefrequencytheimproveandpoweroutputitsincreasetoorderInLED.conventional
opticalresonantainemissionstimulatedtheofadvantagetakemustweperformance,density,currentinjectionhighThecavity. J C >∼ kA25 ⁄cm2 devicepresenttheinobtained,
longconventionalinthattocomparableefficiency,radiativeinternalhighitsandtransferreal-spaceaofimplementationfuturetheforpromisingareLED’s,wavelength
laser.logicnonlinearcomplicatedashowdeviceslogicRSTtheoptically,andelectricallyBoth
ondependencesstateinternaltheininstabilities,novelofvarietyaincludingbehavior,usetotheoretical,andexperimentalbothrequired,isworkMuchvoltages.inputthe
functionalfastofimplementationtheforfashioncontrolledaininstabilitiesthesedevices.
ACKNOWLEDGEMENTS
Cho,Y.A.Capasso,F.Belenky,L.G.collaboratorsourthanktowishWetocontributionstheirforSivcoL.D.andPinto,R.M.Hutchinson,L.A.Garbinski,A.P.
here.reviewedworkthe
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