简介:DistributedBraggreflectors(DBRs)areessentialcomponentsforthedevelopmentofoptoelectronicdevices.Inthispaper,wefirstreporttheuseofthenanoporousGaN(NP-GaN)DBRasatemplateforregrowthofInGaN-basedlight-emittingdiodes(LEDs).Thewafer-scaleNP-GaNDBR,whichisfabricatedbyelectrochemicaletchinginaneutralsolution,hasasmoothsurface,highreflectivity(>99.5%),andwidespectralstopbandwidth(>70nm).ThechemicalcompositionoftheregrownLEDthinfilmissimilartothatofthereferenceLED,butthephotoluminescence(PL)lifetime,PLintensity,andelectroluminescenceintensityoftheLEDwiththeDBRareenhancedseveraltimescomparedtothoseofthereferenceLED.TheintensityenhancementisattributedtothelightreflectioneffectoftheNP-GaNDBRandimprovedcrystallinequalityasaresultoftheetchingscheme,whereastheenhancementofPLlifetimeisattributabletothelatter.
简介:Monolithicwhite-light-emittingdiodes(whiteLEDs)withoutphosphorsaredemonstratedusingInGaN/GaNmultiplequantumwells(MQWs)grownonGaNmicroringsformedbyselectiveareaepitaxyonSiO2maskpatterns.Themicroringstructureiscomposedof{1-101}semi-polarfacetsanda(0001)c-plane,attributedtofavorablesurfacepolarityandsurfaceenergy.ThewhitelightisrealizedbycombiningshortandlongwavelengthsofelectroluminescenceemissionsfromInGaN/GaNMQWsonthe{1-101}semi-polarfacetsandthe(0001)c-plane,respectively.ThechangeintheemissionwavelengthsfromeachmicrofacetisduetotheIncompositionvariationsoftheMQWs.Theseresultssuggestthatwhiteemissioncanpossiblybeobtainedwithoutusingphosphorsbycombiningemissionlightfrommicrostructures.
简介:ThinheavilyMg-dopedInGaNandGaNcompoundcontactlayerisusedtoformNi/AuOhmiccontacttop-GaN.ThegrowthconditionsofthecompoundcontactlayeranditseffectontheperformanceofNi/AuOhmiccontacttop-GaNareinvestigated.Itisconfirmedthatthespecificcontactresistivitycanbelowerednearlytwoordersbyoptimizingthegrowthconditionsofcompoundcontactlayer.WhentheflowrateratiobetweenMgandGagassourcesofp++-InGaNlayeris10.6%andthethicknessofp++-InGaNlayeris3nm,thelowestspecificcontactresistivityof3.98×10-5?·cm2isachieved.Inaddition,theexperimentalresultsindicatethatthespecificcontactresistivitycanbefurtherloweredto1.07×10-7?·cm2byoptimizingthealloyingannealingtemperatureto520℃.
简介:Realizationofefficientyellow-light-emittingdiodes(LEDs)hasalwaysbeenachallengeinsolid-statelighting.Greatefforthasbeenmade,butonlyslightadvancementshaveoccurredinthepastfewdecades.AftercomprehensiveworkonInGaN-basedyellowLEDsonSisubstrate,wesuccessfullymadeabreakthroughandpushedthewall-plugefficiencyof565-nm-yellowLEDsto24.3%at20A∕cm~2and33.7%at3A∕cm~2.ThesuccessofyellowLEDscanbecreditedtotheimprovedmaterialqualityandreducedcompressivestrainofInGaNquantumwellsbyaprestrainedlayerandsubstrate,aswellasenhancedholeinjectionbya3DpnjunctionwithV-pits.
简介:有数组结构的InGaN/GaNmulti-quantum-well-structure激光二极管成功地在蓝宝石底层上被制作。激光二极管由在一个激光薄片上分享普通电极的四根emitter条纹组成。一个800-mm-long洞被劈开底层沿着形成(1100)取向使用激光scriber。激光数组二极管的阀值电流和电压分别地是2A和10.5V。在在房间温度的搏动的当前的注射下面的12W的轻产量山峰力量被完成。我们模仿电的性质在共面的结构和最小化在不同山脉和n电极之间的距离的差别并且增加n类型的电的电导率轧了的结果表演轧了基于的激光二极管是在emitter条纹改进搬运人分发的一致性的二个有效方法。一个薄片上的二emitters被安排在二n电极垫附近位于左边,右边,和四条纹emitters一起装激光。激光二极管在阀值电流上面在408和409nm显示出轻输出的二座锋利的山峰。在为平行、垂直的远域模式的半最大值的完整的宽度分别地是8o和32o。[从作者抽象]