Fig. 1: Wafer-scale atomic layer deposition of amorphous boron nitride.
From: Tailoring amorphous boron nitride for high-performance two-dimensional electronics
a Schematic illustration of the ALD process for BN thin films. b Raman spectra of aBN (black) and hBN (red). The in-plane E2g vibrational mode of hBN is observed at 1369 cm−1, which is absent in aBN due to the lack of crystalline order. c Camera image and overlaid map of film thickness measured by spectroscopic ellipsometry of as-deposited aBN (300 ALD cycles) on a 150 mm Si wafer. d Thickness of aBN deposited at 250 °C as a function of ALD cycle number. A linear fit (blue) is used to obtain a growth rate of 0.34 Å/cycle after the initial nucleation delay. e HAADF-STEM cross-sectional image of Au-capped aBN deposited on SiOx at 250 °C for 300 ALD cycles. f EELS characteristics of B-K and N-K from the selected points in (e). g HAADF-STEM cross-sectional image of aBN deposited at 250 °C for 300 ALD cycles on a damascene structure made of SiOx. The aBN is highlighted with yellow dotted lines. h Cross-sectional HAADF-STEM image in the green selected area in (g). i EDS mapping of Si, C, and N in the orange selected area in (g).
