简介：Thisworkinvestigatesinternalplasmaprocessparametersusingahairpinresonanceprobeandopticalemissionspectroscopy.ThedependenceofelectrondensityandatomicfluorineonthepercentageofoxygeninanSF6/O2dischargewasmeasuredusingthesemethods.AnRIEOxfordInstruments80pluschamberwasusedfortheexperiments.Twodifferentprocesspowers(100Wand300W)ataconstantpressure(100mTorr)wereused,anditwasfoundthattheopticalemissionintensityofthe703.7nmand685.6nmlinesofatomicfluorineincreasedrapidlyasoxygenwasaddedtotheSF6discharge,reachedtheirmaximumatanO2fractionof20%andthendecreasedwithfurtheradditionofoxygen.TheplasmaelectrondensitywasalsostronglyinfluencedbytheadditionofO2.

简介：本文描述了GdB5O9、NaGdF4的合成与结构以及NaGdF4在高温下的相转变。粉末衍射数据表明GdB5O9属于四方晶系，其空间群为：I4l／acd，晶胞参数为：α=8．23813。c=33．6377。六方和立方NaGdF4分别与NaEuF4和CaF2同构。本文还考察了GdB5O9：Eu、六方NaGdF4：Eu、立方NaGdF4：Eu样品的真空紫外(VUV)荧光性质．上述三种样品中Gd3+的4f-5d跃迁及基质的吸收位于真空紫外波段。

简介：本文通过对三聚氰胺(C3N6H6)的室温高压原位同步辐射能量散射x-ray衍射实验（EDXRD），在14．7GPa压力范围内，观察到常压下为单斜晶系的三聚氰胺经历了两次压致结构相变。在1．3GPa下，三聚氰胺分子晶体从单斜相转变为三斜相；在8．2GPa又转变为正交相。

简介：Anewtwo-dimensionalstructuremodulationalongc-andb-axeshasbeendiscoveredinsuperconductingsinglecrystalsofBi2.13Sr1.87CuO6+δ(Bi2201)byx-rayscattering.Suchmodulationstructuredoesnotexistinnon-superconductingBi2201singlecrystals.Butinsteadlatticedistortionsareobservedinthea-b-plane.Thisphenomenonmayindicatethatbothstrainrelaxationandchargemodulationinthea-b-planeareimportanttotheoccurrenceofsuperconductivityinthecopperoxides.

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简介：ThisworkinvestigatedC2F6/O2/ArplasmachemistryanditseffectontheetchingcharacteristicsofSiCOHlow-kdielectricsin60MHz/2MHzdual-frequencycapacitivelycoupleddischarge.FortheC2F6/Arplasma,theincreaseinthelow-frequency(LF)powerledtoanincreasedionimpact,promptingthedissociationofC2F6withhigherreactionenergy.Asaresult,fluorocarbonradicalswithahighF/Cratiodecreased.Theincreaseinthedischargepressureledtoadecreaseintheelectrontemperature,resultinginthedecreaseofC2F6dissociation.FortheC2F6/O2/Arplasma,theincreaseintheLFpowerpromptedthereactionbetweenO2andC2F6,resultingintheeliminationofCF3andCF2radicals,andtheproductionofanF-richplasmaenvironment.TheF-richplasmaimprovedtheetchingcharacteristicsofSiCOHlow-kfilms,leadingtoahighetchingrateandasmoothetchedsurface.