Fig. 1
From: Realization of wafer-scale nanogratings with sub-50 nm period through vacancy epitaxy
Fabrication of the nanograting substrates. a Schematic of the vacancy epitaxy on GaAs(001) surfaces. b, c AFM and XTEM images of the sawtooth GaAs substrate with a nanogroove density over 20,000 lines mm−1 and (d) distribution of the facet angles over the AFM image, mostly 19°. e–g AFM images of the GaAs (001) substrates and their cross-section profiles along the [110] direction irradiated at 450 °C, 480 °C, and 520 °C. The periodicities of the nanogratings are 48 nm (e), 55 nm (f), and 78 nm (g), respectively. h–j SEM and XTEM images of the nanogroove structures formed on GaAs (001) with a miscut angle of 0°, 10°, and 15° toward the [110] direction. The periodicities of the nanogratings are 48 nm (h), 55 nm (i), and 155 nm (j), respectively
