In-plane strain states of standard and flip-chip GaN epilayers Z. Y. Zuo, D. Liu, R. J. Wang, S. B. Qin, H. Liu and X. G. Xu Eur. Phys. J. Appl. Phys., 54 1 (2011) 10101 Published online: 13 April 2011 DOI: 10.1051/epjap/2011100454