超深亞微米NMOSFET中的熱載流子效應(yīng).pdf

1、西安電子科技大學(xué)碩士學(xué)位論文超深亞微米NMOSFET中的熱載流子效應(yīng)姓名：邢德智申請學(xué)位級別：碩士專業(yè)：微電子學(xué)與固體電子學(xué)指導(dǎo)教師：劉紅俠20070101AbstractAbstractWiththescalingofdevicesizeintoultradeepsubmicronandnanegion，hotcarriereffectisalsoanimportantreliabilityissueinCMOScircuit，its

2、degradationmechanismsandimpactondevicecharacteristicsarediscusseddeeplyinthisdissertationFirstthebasicphysicalmechanismsandimpact—ionizationmechanismsunderlowsupplyvoltageinultra—deepsubmicronNMOSFET’SareintroducedThedeg

3、radationofNMOSFET’SIVcharacterandstaticparametersunderhotcarrierstressconditionarepresentedThesaturationeffectofdevicedegradationisinvestigatedTheworstcasestressconditionisalsodiscussedThreegroupsofNMOSFETwithdifferentox

4、idethicknessaremeasuredtostudythesubstratecurrentcharacteristicsIt’SexperimentallydemonstratedthatthemaximumsubstratecurrentstressconditionswishfromVgs≈l／2VdstoVgs=VasinNMOSFETwhosechannellengthis0091xm，theoxidethickness

5、is124nmItisfoundthatinshortchannelthingateoxideNMOSFETthedevicelifetimeunderchannelhotcarderstressislowerthanthatunderdrainavalanchehotcarrierstress，contrarytotheusualthinkingthattheworstcasestressconditiondependsonthega

6、tevoltagewiththemaximumsubstratecurrent，thereasonsofthisphenomenonareanalyzedAtlast，themechanismsandcharacteristicsoftrapassistedtunnelingdrainleakagecurrent(ITAT)degradationareinvestigatedBothinterfacetrapandoxidetrappe

7、dchargeareanalyzedTheexperimentalresultsshowthatthehotcarrierstressmakesITATdegradationhaveastrongdependenceontheoxidethicknessInthingateoxide(theoxidethicknesstox=384nm)NMOSFETITATdegradationisattributedmostlytointerfac

8、etrapcreation，whileinthickeroxide(theoxidethicknesstox=764nm)NMOSFETITATexhibitstwostagesdegradation，apowerlawdegradationrateintheinitialstageduetointerfacetrapgeneration，followedbyanaccelerateddegradationrateinthesecond