Optical and defect properties of S-doped and Al-doped GaSe crystals
Huang Chang-Bao, WuWu Hai-Xin †, Ni You-Bao, Wang Zhen-You, Chen Shi-Jing
       

The SEM pictures with different resolution of (a), (b) pure, (c), (d) S-doped, and (e), (f) Al-doped GaSe crystals.