We report on an AlN/AlGaN superlattice approach to grow high-Al-content thick n+-AlGaNlayers over c-plane sapphire substrates. Insertion of a set of AlN/AlGaN superlattices is shown to significantly reduce the biaxial tensile strain, thereby resulting in 3-μm-thick, crack-free Al0.2Ga0.8N layers. These high-quality, low-sheet-resistive layers are of key importance to avoid current crowding in quaternary AlInGaN multiple-quantum-well deep-ultraviolet light-emitting diodes over sapphire substrates.
Published in Applied Physics Letters, Volume 80, Issue 19, 2002, pages 3542-3544.
©Applied Physics Letters 2002, American Institute of Physics (AIP).
Zhang, J. P., Wang, H. M., Gaevski, M. E., Chen, C. Q., Fareed, Q., Yang, J. W., Simin, G., & Khan, M. A. (13 May 2002). Crack-Free Thick AlGaN Grown on Sapphire using AlN/AlGaN Superlattices for Strain Management. Applied Physics Letters, 80 (19), 3542-3544. http://dx.doi.org/10.1063/1.1477620