HIGH-BRIGHTNESS LIGHT-EMITTING-DIODES GROWN BY MOLECULAR-BEAM EPITAXYON ZNSE SUBSTRATES

High-brightness blue and green light-emitting diodes (LEDs) operating at peak wavelengths in the range 489-514 nm have been successfully syn thesized, processed, and tested. The high-brightness LEDs are II-VI he terostructures grown by molecular beam epitaxy at North Carolina State University using (100) ZnSe substrates produced at Eagle-Picher Labor atory by the seeded physical vapor transport process. The blue LEDs (4 89 nm) produce 327 mu W at 10 mA drive current with an external quantu m efficiency of 1.3%. In terms of photometric units, the luminous perf ormance of the ZnCdSe blue LEDs is 1.7 lm/W at 10 mA. The brightest Zn TeSe green LEDs tested to date produce 1.3 mW at 10 mA peaked at 512 n m with an external quantum efficiency of 5.3%. The luminous performanc e of the green LEDs is 18 lm/W at 10 mA. Using recently-developed n-ty pe conducting ZnSe substrates, green LEDs having external quantum effi ciencies of 2.7% have also been demonstrated. (C) 1995 American Vacuum Society.