Surfactant-assisted chemical vapour deposition of high-performance small-diameter GaSb nanowires

Abstract

Although various device structures based on GaSb nanowires have been realized, further performance enhancement suffers from uncontrolled radial growth during the nanowire synthesis, resulting in non-uniform and tapered nanowires with diameters larger than few tens of nanometres. Here we report the use of sulfur surfactant in chemical vapour deposition to achieve very thin and uniform GaSb nanowires with diameters down to 20 nm. In contrast to surfactant effects typically employed in the liquid phase and thin-film technologies, the sulfur atoms contribute to form stable S-Sb bonds on the as-grown nanowire surface, effectively stabilizing sidewalls and minimizing unintentional radial nanowire growth. When configured into transistors, these devices exhibit impressive electrical properties with the peak hole mobility of B200 cm 2 V À 1 s À 1 , better than any mobility value reported for a GaSb nanowire device to date. These factors indicate the effectiveness of this surfactant-assisted growth for high-performance small-diameter GaSb nanowires.

Impact of doping and diameter on the electrical properties of GaSb nanowires

“…4 While the synthesis, processing, and applications of III-V materials have been studied for more than a decade, research on III-Sb NWs has attracted a growing interest only recently. [5][6][7][8][9] GaSb, in particular, is an increasingly important material for a III-V p-channel metaloxide-semiconductor field-effect transistor (MOSFET) due to its high hole mobility. 10 However, the mobility is highly dependent on the materials synthesis method and device structure.…”

Fabrication of Sub-25 nm Diameter GaSb Nanopillar Arrays by Nanoscale Self-Mask Effect

“…This is among one of smallest diameters obtained for GaSb nanowires/ nanopillars. 22,24,30 The aspect ratio of these nanopillars was estimated to approximately 24, which is larger than the previously reported top-down etched GaSb nanopillars with silica, 25 Au, 24 and resist 23 masks. The high resolution TEM (HRTEM) image and the corresponding fast Fourier transform (FFT) of a representative nanopillar show that the nanopillar has a diameter of 18.2 nm and a zinc blende crystalline structure ( Figure 1e).…”

Brief Review of Epitaxy and Emission Properties of GaSb and Related Semiconductors

“…Yang et al reported the growth of GaSb nanowires on Si substrates using CVD. However, these GaSb NWs were coil-like and became intertwined, which made device fabrication difficult [70]. A. H. Chin used GaSb subwavelength wires with a cross-sectional dimension of 700-1500 nm and lengths of 10-70 µm to lase at approximately 1550 nm, as shown in Figure 12 [71].…”