Research Of Luminous Intensity On AlGaInP LED

AlGaInP belongs to quaternary materials,which has direct gap.Itsluminescence wavelength range from red to yellow-green in visiblespectrum.Thus,AlGaInP semiconductor materials was widely used inhigh-brightness light emitting diode and many kinds of Optoelectronicdevices.Further to improve the LED luminousintensity,we investigated theproperties quaternary AlGaInP materials and designed better structure andepitaxy growth technology. The thesis conclude following threeoptimization,namely LED External Quantum Efficiency (EQE) enchanced byDistributed Bragg reflectors (DBR),.Multiple quantum well structure improveinternal quantum efficiency (IQW) and GaP Window layer optimation.1.We designed two types of DBR structure,these reflective wavelengthwere570nm and625nm,respectively.The two epitaxy layers were growed onGaAs substrate by organometallic vapor phase epitaxy.These samples weremade to chip by chip technology.We characterized the sample propertie byXRD,PL,and chip Optoelectronic testing device.The results suggested that red LED luminousintensity is better than that of yellow-green.This result wasarise from yellow-green IQW is low and leading to the low luminousintensity.2.We investigate the barrier thickness,the Al content in barrier materialsand V/III rate affected IQW of MQW structure.we found that the optimazationof the barrier thickness is8nm;the optimazation of the Al content is0.65;theoptimazation of the V/III is80.Under these optimize conditions,improving theIQW of the samples.3.We investigate the Mg flows,doping temperature,and V/III rate effect onthe quality of the GaP window layers.The results suggest that the optimazationof Mg flows is24sccm,the optimazation of the doping temperature is710℃,theoptimazation of V/III is10.Under these optimize conditions,the quality of GaPwindow layer was improved.