Epitaxial Relationship Analysis Between ZnTe Epilayers and Sapphire Substrates

ZnTe layers on R ‐ and S ‐plane sapphire substrates

“…The atom arrangement on the sapphire's surface varies depending on the crystallographic orientation, and domain distributions of ZnTe layers grown on various sapphire substrate surfaces by molecular beam epitaxy (MBE) were reported in previous works [12][13][14][15][16][17][18]. Although there was a large lattice mismatch between ZnTe and sapphire, the improvement of the ZnTe epilayer quality by the insertion of thin buffer layers between the substrate and the epilayer was confirmed [12,13].…”

“…Although there was a large lattice mismatch between ZnTe and sapphire, the improvement of the ZnTe epilayer quality by the insertion of thin buffer layers between the substrate and the epilayer was confirmed [12,13]. A (111)-oriented ZnTe layer with single domain structure was formed on the c-plane sapphire substrate [12,14,18], while a (211)-oriented ZnTe layer was formed on the m-plane (10 10) substrate [13][14][15]. Hence, it was considered that the orientation of the ZnTe epilayer could be varied by using R-plane (10 14) and Splane (10 11) sapphire substrates.…”

“…Hence, it was considered that the orientation of the ZnTe epilayer could be varied by using R-plane (10 14) and Splane (10 11) sapphire substrates. These studies were mainly carried out by using X-ray diffraction (XRD) pole figure imaging analysis, which was revealed to be a powerful method for ZnTe epilayers on sapphire substrates [12][13][14][15][16][17][18]. The interface between ZnTe and sapphire were also evaluated by using the transmission electron microscope and the lattice mismatch accommodation and related strain distribution were analyzed [14,17,18].…”

“…Elemental sources of Zn (Osaka Asahi Metal, 6N super) and Te (Osaka Asahi Metal, 6N super) were used as source materials. Based on the optimized nucleation conditions employed for the layer grown on the c-plane sapphire, a 3.5-nm-thick ZnTe layer buffer was deposited at 100 ºC, and the annealing was performed at 300 °C for 10 min prior to the nucleation of ZnTe layers [12,14,18]. The growth of ZnTe layer was performed at 340 °C, and the growth rate and the film thickness were held constant at around 0.5 μm/hr and 1μm, respectively.…”

“…The growth of ZnTe layer was performed at 340 °C, and the growth rate and the film thickness were held constant at around 0.5 μm/hr and 1μm, respectively. The Zn to Te beam intensity ratio was also fixed at around unity [12][13][14][15][16][17][18].…”