In order to overcome current crowding and reduce the injection current underneath the opaque p-pad electrode in AlGaInP-based light emitting diodes(LEDs),a modified novel LED structure with SiO2 current blocking layer(CBL)was applied in AlGaInP-based LEDs.The novel LED structure was grown on Si-doped GaAs substrates by a low-pressure metal-organic chemical vapor deposition(MOCVD)system.The CBL was inserted into the GaP window layer,for the convenience of device fabrication,in the process of wafer epixial growth,the GaP window layer was thinned to only 500 nm.The GaP layer was partially etched by inductively coupled plasma(ICP)to expose the expected depth,and then refilled with SiO2 by plasma enhanced chemical vapor deposition(PECVD)system.A transparent and conductive ITO layer was then evaporated on thin GaP as a current spreading layer since the poor conductivity of 500 nm GaP.Be/Au and AuGeNi/Au were deposited as p-type and n-type ohmic contact.Finally,the LEDs were annealed at 435 ℃ for 30s.For comparison,traditional AlGaInP-based LEDs with 8 祄-thick GaP window layer were also fabricated.Experiment results show that the novel LEDs presented high performances in optical and electrical properties and better saturation characteristics as compared to traditional LEDs.The improvement is contributed to the advantages of less optical absorption,more uniform of injection current and less heat generation of the novel LEDs.