ZnSe/ZnS Distributed Bragg Reflectors in the Blue Region Grown on (311)B GaAs Substrates

High-reflectivity distributed Bragg reflectors (DBRs) in the blue region consisting of II–VI semiconductors were grown on (311)B GaAs substrates for the first time using metalorganic vapor phase epitaxy. ZnSe/ZnS alternative layers were used as the DBR. To realize atomically flat surfaces, the conditions of the thermal cleaning and the growth of ZnSe and ZnS on (311)B GaAs surfaces were investigated using atomic force microscopy and X-ray diffraction. The supply of sufficient organic As flow during the thermal cleaning led to extremely-flat (311)B GaAs surfaces, and it was attributed to the suppression of As desorption from (311)B surfaces. Through the examination of the growth conditions for ZnSe and ZnS layers on (311)B GaAs substrates, a DBR with a high reflectivity was fabricated. The maximum reflectivity of the ZnSe/ZnS DBR grown on the (311)B GaAs substrate, measured at room temperature, was 94.5% with only 10 periods at a wavelength of 468 nm, which is in good agreement with the calculated reflectivity of 94.8%.