1、Future Trends in Light ing: Solid State utu e e ds g t g:Sod StateLighti ngPate nt Issue :LED and LED PackagePate nt Issue : LED and LED PackageH.C. KuoNCTU,hckuofaculty. .twNCTU Semic on ductor Laser Tech no logyLaboratory3-1tliOutl inesFuture Trends in Light in g:Solid StateFuture Trends i

2、n Light ing: Solid StateLighti ngReview of GaN material and processReview of GaN material and processPate ntApplicati on and SummaryApplicati on and SummaryNCTU Semic on ductor Laser Tech no logyLaboratory3-2The LED developme nt and applicati onThe LED developme nt and applicati onNCTU Semic on duct

3、or Laser Tech no logyLaboratory3-3E D for SSLNCTU Semico nductor Laser Techn ology Laboratory3-4g a p (e B a n d Lattice con sta nt (?NCTU Semic on ductor Laser Tech no logy Laboratory3-6Major Adva ntageMajor Disadva ntagej gDirect Wide ban dgapDi t b d f I G N d AlG N High defect den sityWith t it

4、bl b t t (134% Direct bandgap of InGaN and AIGaN series materialsFull visible color emissionHighly chemical stabilityWithout suitable substrates (13.4% on Al2O 3a nd 3.4% on SiC Lower con ce ntrationof p-type Highly chemical stability High Saturated electron drift velocity Highbreakdown electric fie

5、ldl di l t i t t GaN:Mglower p-type activati on efficie ncy by thermal treatme ntWafer dime nsion costlow dielectric con sta nt Un ique emissi on spectra Radiati on resista neeWafer dime nsion cost dry etch ing process domin ated the device fabricati onOxidati on/jun cti on passivati onj pNCTU Semic

6、 on ductor Laser Tech no logy Laboratory3-7tliOutl inesFuture Trends in Light in g:Solid StateFuture Trends in Light ing: Solid StateLighti ngReview of GaN material and processReview of GaN material and processProcess Pate ntApplicati on and SummaryApplicati on and SummaryNCTU Semic on ductor Laser

7、Tech no logy Laboratory3-8NCTU Semic on ductor Laser Tech no logyLaboratory3-9NCTU Semic on ductor Laser Tech no logy Laboratory3-12 Process determ inesthe properties and nature of the LEDINCTU Semic on ductor Laser Tech no logyLaboratory3-13NCTU Semic on ductor Laser Tech no logyLaboratory3-14Aixtr

8、o n Model-G3 2400 reactorNCTU Semico nductor Laser TechnologyLaboratory3-15Cooli ng water at 20o Cboun dary layerPump outSource in S o =2.4(v/a0.5RF heati ng to 1050o C NCTU Semico nductor Laser Tech no logyLaboratory3-16V=0 at surfaceEMCORE(NCTU垂直式反應器-EMCORE(NCTUNCTUSemico nductorLaser Tech nologyL

9、aboratory3-17NCTU Semic on ductorLaser Tech no logyLaboratory3-18Optimum Growth Con ditionsP1. Temperature2. V/lll ratioNCTU Semic on ductorLaser Tech no logyLaboratory3-193. Total flow rateNCTU Semic on ductor Laser Tech no logy Laboratory3-20th t fti f t t h i th Growth rate as a function of tempe

10、rature showing thethree distinctgrowth-rate regimes.NCTU Semic on ductor Laser Tech no logy Laboratory3-21NichiaGaN blue LED on Al Substrate with top electrodeGaN blue LED on Al2O 3 Substrate with top electrodeNCTU Semico nductor LaserTech no logy Laboratory3-21GaN blue LED on SiC Substrate with bot

11、tom electrodeCreeGaN blue LED on SiCSubstrate with bottom electrodeNCTU Semico nductor LaserTech no logy Laboratory3-222GaN LED process flowchart(2 Etch ing mesa using Ni mask(3n-con tact Metal depositi on pICP plasmaTi/AI P-typen-type (500?/1000? n type(4TCL-co ntact Metal depositio n(5RTA : N,430,

12、 120sec ( p ( ,C ,(1 Epitaxial structureNi/Au(50?/50?NCTU Semic on ductor Laser Tech no logy Laboratory3-25Why ITO GaN Based LEDITO sta nd for Tin doped in dium oxide (In 2O3NCTU Semic on ductor Laser Tech no logy Laboratory3-28GaN tran spare nt con tactp-electrode tran spare nt con tact layer+l t d

13、p-GaN MQWs n-electrode n-GaN Al 20 3 substrateAl 2O 3 substrate Sapphire substrate :Electrical in sulatorRelatively low thermal con ductivityfl i i f G N/hi if Low reflectivity of n-GaN/sapphire in terface Lateral curre nt flow :Curre nt crowd ing effectLow con ductivity of p GaNNCTU Semic on ductor Laser Tech no logy Laboratory3-29Low con ductivity of p-GaNNiAu tran spare nt con tact (18NCTU Semic on ductor Laser Tech no logyLaboratory3-30Pate nt No: 5563422, Dateof pate nt: Oct.8 1996.Pate nt No: 5998925, Date of pate nt: Dec 7