Interference effects in the electroreflectance and electroluminescence spectra of InGaN/AlGaN/GaN light-emitting-diode heterostructures

Interference effects in InGaN/AlGaN/GaN light-emitting-diode heterostructures of blue emission are studied by spectroscopy of electroreflectance and electroluminescence. The periodic bands observed in the electroreflectance and electroluminescence spectra in a blue spectral range are caused by interference effects in the structure in general. The emergence of interference fringes in the electroreflection spectra is explained by modulation of built-in electric fields in the active region of the heterostructure. The long-period interference fringes observed in the electroreflectance spectra in a wide spectral range from infrared to ultra-violet allows one to determine the location of the active region of the heterostructure with respect to different reflecting surfaces in the cavity.