《nano-textured indium-tin-oxide layer》.pdf

Vo1．35，No．8 JournaIofSemiconductors AUClust2014 GaN--basedlight--emittingdiodeswithhybridmicro／nano-texturedindium--tin-oxide layer HuangHuamao(黄华茂)，HuJinyong(胡金勇)，andWangHong(t~)* EngineeringResearchCenterfor0ptOelectrOnicsofGuangdongProvince，DepartmentofPhysics，SchoolofScience，South ChinaUniversityofTechnology,Guangzhou510640，China Abstract：Threetypesoftexturedindium—tin—oxide (ITO1surface includingnano—texturing andhybrid micro／nano．texturingwithmicro．holes(concave—hybrid—pattem)ormicro—pillars(convex—hybrid—pattern)．were appliedtoGaN．basedlight．emittingdiodes(LEDs)．Thenano—texturingwasrealizedbymasklesswet．etching． andthemicro．texturingwasachievedbystandardphotolithographyandwet．etching．ComparedtoLED chipswith fiatITO surface，thosewithnano．pattern concave．hybrid—pattern ，andconvex—hybrid—patternexhibitenhancement of11-3％．15．8％ and17．9％．respectively,forthelight．outputpowersat20mA．Theelectricalperformancehas nodegradation．Moreover,theconvex．hybrid—pattern showhigherlight—outputefficiencyundersmallinjection current．whiletheconcave．hybrid．patternexhibitbetterlight．outputefficiencyatlargeinjectioncurrent．Thelight． extractionefhciencyissimulatedbyuseoftwo—dimensionalfinitedifferencetimedomainmethod，andthenumer- icalresultsareconsistentwiththeexperiments． Keywords：light-e·mittingdiodes；hybridmicro／nano-·textured；indium--tin--oxide；light--output DoI：10．1088／1674—4926／35／8／084006 EEACC：2570 strucutre isthemasklesswet．etchingtechnique[1~一141 ．