Fluorinated Graphene in Interface Engineering of Ge‐Based Nanoelectronics

Abstract

Germanium is a promising candidate to replace silicon in nanoelectronics due to its significantly higher electron and hole mobilities. However, the unstable germanium oxide formed at the interface between the channel and dielectric layer has impeded the progress of Ge‐based nanoelectronics. By taking advantage of the impermeability of graphene, it is discovered that the insulating fluorinated graphene is able to act as an efficient diffusion barrier layer to suppress the formation of the unstable interfacial oxide in Ge‐based devices. The Ge‐based device with the fluorinated graphene exhibits negligible capacitance versus voltage hysteresis, extremely low leakage, and superior equivalent oxide thickness. First‐principles calculations reveal that interfacial diffusion, which would otherwise be unmanageable, is sufficiently obstructed by the fluorinated graphene. This new structure is expected to expedite the implementation of germanium as a channel material in next‐generation nanoelectronic devices.

Electrical Transport in Devices Based on Edge‐Fluorinated Graphene

“…[1][2][3][4][5] The layered 2D nature of graphene in particular allows a multitude of possibilities for the application of its fluorinated derivatives for, e.g., sensors, [6,7] energy storage, [8][9][10][11] or nanoelectronic [12,13] components. [1][2][3][4][5] The layered 2D nature of graphene in particular allows a multitude of possibilities for the application of its fluorinated derivatives for, e.g., sensors, [6,7] energy storage, [8][9][10][11] or nanoelectronic [12,13] components.…”

“…This implies potentially significant qualitative and quantitative differences in the device response. [1][2][3][4][5] The layered 2D nature of graphene in particular allows a multitude of possibilities for the application of its fluorinated derivatives for, e.g., sensors, [6,7] energy storage, [8][9][10][11] or nanoelectronic [12,13] components. Considering the electrical conductivity of individual mono-and fewlayer flakes, it is dominated by the type, amount, and bonding position (basal or edge) of functional groups attached to the C(sp 2 ) matrix.…”

“…Specifically, the presence of edges in graphene can be decisive. To date, multiple methods for graphene fluorination have been extensively studied [8,10,[13][14][15][16][17][18][19][20][21] and it has been shown that the F content can be varied controllably by adjusting the reaction conditions. In thin film-based systems, however, the charge transport also is largely affected by the properties of edge/edge, edge/plane, and plane/plane junctions.…”

Solvent‐Based Soft‐Patterning of Graphene Lateral Heterostructures for Broadband High‐Speed Metal–Semiconductor–Metal Photodetectors

“…[10][11][12] A thorough review of FG is also recently published. [12] The binding of F radicals to graphene leads to surface activation and band gap opening, [11][12][13] rendering the resultant FG useful for applications ranging from as a seed layer for dielectric deposition [14,15] to as a growth precursor for synthesis of new 2D materials [16] and a building block for 2D heterostructures. [17] While FG, like some of the other functionalized graphene forms, holds great promises as a complementary material for next generation graphene-based electronics, it can readily defluorinate under humid conditions or when in contact with acetone [7,18] Such a phenomenon, considering acetone an important solvent for FG transfer and patterning process, can seriously undermine the potential of FG for widespread applications.…”

Barrier Reduction of Lithium Ion Tunneling through Graphene with Hybrid Defects: First‐Principles Calculations

“…[16,[30][31][32][33] As shown in Figure 5, compared to primary graphene, boron and nitrogen substitution is taken into consideration to analyze the influence on the tunneling barrier. Edge-doping of B, C, N, and O into zigzag graphene nanoribbons can maximize loading of charges.…”