Fig. 1: Fabrication of the FEB and its semiconductor-less device characteristics.
From: Semiconductor-less vertical transistor with ION/IOFF of 106
a Optical microscopic image of an FEB consisting of stacked metal/hBN/graphene/hBN/metal (scale bar 20 μm). (inset) Scanning electron microscopic image of polymethyl methacrylate (PMMA) bridges, which help thin metal electrodes connect through the thick stack (scale bar: 5 μm) (for more detail, see the “Methods” section). b Schematic diagram of the FEB applying VD and VG. c, d Band diagrams of the FEB (VD > 0) under FE-dominant (c) and DT-dominant conditions (d). The VG modulates the accumulation of electrons on the graphene. e, f Band diagrams of the FEB (VD < 0) under DT-dominant (e) and FE-dominant conditions (f). The VG modulates the accumulation of holes on the graphene. The gate voltage decreases from c to f. g ID switching performance of the semiconductor-less device. ID− and IG− are drain and gate current under VD = −18 V. ID+ and IG+ are drain and gate current under VD = 29 V. For the negative VG, ION/IOFF above 106 has been achieved at 300 K. h Device characteristics of the n-type FEB (VD > 0) at 300 K (left) and 15 K (right). i Device characteristics of the p-type FEB (VD < 0) at 300 K (left) and 15 K (right). For both types, very little temperature degradation of ID was observed. j ID switching under VD = −18 V (red) and 29 V (black) also exhibited little temperature degradation from 400 to 15 K.
