The modulation-doped AlGaN/GaN heterostructure layers were used to improve the output power and efficiency of nitride-based blue light emitting diodes (LEDs). It was found that the output power of LEDs with the modulation-doped AlGaN/GaN layers measured at 20 mA injection current was increased from 4.8 to 6 mW. It was also found that the modulation-doped AlGaN/GaN layers can effectively spread pulse current. Nitride-based blue LEDs with the modulation-doped AlGaN/GaN layer can even endure a 3000 V reverse electrostatic discharge pulse voltage. (c) 2006 American Vacuum Society.