Fig. 2: Properties of Al/c-Al2O3 gate.
From: Single-crystalline metal-oxide dielectrics for top-gate 2D transistors
a, Schematic (left), cross-sectional HR-TEM (middle) and magnified atomic-resolution (right) images of an Al/c-Al2O3/MoS2 heterostructure. b, Selected area electron diffraction patterns (top) obtained from the dashed green, orange and blue boxes in a. Line intensity profiles (bottom) along the dashed green, orange and blue lines in a. c, HR-TEM image of a-Al2O3/MoS2 (left) and the important tunnelling contributions (right). d, HR-TEM image of c-Al2O3/MoS2 (left) and the important tunnelling contributions (right). e, Experimental gate leakage currents for 2D FETs with c-Al2O3 and a-Al2O3. f, The relationship between current and gate voltage. VTG, top-gate voltage; VBG, back-gate voltage. g, The relationship between EOT and dielectric thickness. h, Experimental gate leakage currents compared with EOT measured at standard operating gate voltages of 1 V. i, Noise power spectra as a function of frequency. j, Comparison of Dit values measured for Si devices and different 2D technologies. Scale bars, 5 nm (a, bottom row, middle); 2 nm (a, bottom row, right); 2 nm (c,d). TAT, trap-assisted tunnelling.
