利用多孔衬底HVPE生长GaN单晶及其不同晶面性质的研究.docx

利用多孔衬底HVPE生长GaN单晶及其不同晶面性质的研究
Title:StudyofGaNSingleCrystalGrowthonPorousSubstrateHVPEanditsDifferentCrystalFaceProperties
Abstract:
GaN(galliumnitride)hasgainedsignificantattentioninrecentyearsduetoitswiderangeofapplicationsinoptoelectronics,powerdevices,andhigh-frequencyelectronics.However,thegrowthofhigh-qualityGaNsinglecrystalsremainsachallenge.ThisstudyfocusesonthegrowthofGaNsinglecrystalsusingthehydridevaporphaseepitaxy(HVPE)methodonporoussubstratesandexploresthepropertiesofdifferentcrystalfaces.
1.Introduction:
GaNisapromisingmaterialfornumerousapplications,primarilyduetoitsexcellentelectrical,optical,andthermalproperties.Itpossessesawidebandgap(3.4eV)andahighelectronsaturationvelocity,makingitsuitableforhigh-powerandhigh-frequencyelectronicdevices.Thesynthesisofhigh-qualityGaNsinglecrystalsiscrucialforenhancingtheperformanceofsuchdevices,andHVPEisapreferredmethodduetoitssimplicityandscalability.
2.ExperimentalMethodology:
2.1PorousSubstratePreparation:
PoroussubstratesarepreparedbyetchingtechniquesusingvariousnitridecompoundslikeAlNorGaN.Thisprocessprovidesatemplateforcrystalgrowthandimprovestheoverallquality.
2.2HVPEGrowth:
TheHVPEtechniqueisutilizedtogrowGaNsinglecrystalsonthepreparedporoussubstrates.TheprecursorgasesincludeHCl,NH3,andGaCl3.Thegrowthparameterssuchassubstratetemperature,gasflowrates,andgrowthtimeareoptimizedtoachievehigh-qualitycrystals.
3.CharacterizationTechniques:
ThefollowingtechniquesareemployedtoinvestigatethecrystalgrowthandsurfacemorphologyofHVPE-grownGaNsinglecrystals:
3.1X-rayDiffraction(XRD):
XRDisusedtoanalyzethecrystalstructureandlatticeparametersoftheGaNsamples.Theorientationandcrystallinityaredeterminedfromthediffractionpatterns.
3.2ScanningElectronMicroscopy(SEM):
ThesurfacemorphologyandqualityoftheGaNcrystalsarestudiedusingSEM.Thistechniquerevealsthegrainsize,defects,andsurfaceroughness.
3.3AtomicForceMicroscopy(AFM):
AFMprovidesadetailedinsightintothesurfacetopographyandroughnessoftheGaNsamples.Itoffershigh-resolutionimagin