Atomic-scale tomography of semiconductor nanowires

Direct Observation of Dopants Distribution and Diffusion in GaAs Planar Nanowires with Atom Probe Tomography

“…However, unintentional impurities can degrade the performance of devices, , such as forming deep level recombination centers and leading to negative effects on electronics, photonics, and optoelectronics. − These adverse doping effects are usually unintentional and occur at low concentrations which cannot be detected by traditional characterizing technique due to their insufficient sensitivity and resolution. Capable of volumetrically mapping elements of materials in both quantitative and qualitative aspects with better than 0.3 nm spatial resolution in all direction, atom probe tomography (APT) provides atomic-level insights into materials. − In this paper, GaAs planar NWs intentionally doped with silicon and zinc were grown on a thin Al 0.3 GaAs film on top of a GaAs (100) substrates by MOCVD, and APT experiments were carried out to quantitatively determine the doping distribution in the epilayers and interfaces.…”

Nanowire Electronics: From Nanoscale to Macroscale

“…To date, a wide range of semiconductor nanowires (e.g., group V, III–V, and II–VI semiconductors and their alloys) have been synthesized with excellent electronics properties comparable to and in some cases surpassing that of the bulk single-crystal materials. ,− For example, carrier mobility values of 900 cm 2 /(V s) have been realized for n -type Si nanowires, 2250 cm 2 /(V s) for p -type GaAs nanowires, 11 500 cm 2 /(V s) for InAs/InP core–shell nanowires, 25 000 cm 2 /(V s) for InSb nanowires, and up to 50 000 cm 2 /(V s) for GaAs/Al 0.16 Ga 0.84 As core–multishell nanowires . Furthermore, semiconductor nanowires can be prepared with highly reproducible electronic properties, which is critical for large-scale integrated circuits. ,− In contrast, the synthesis of carbon nanotubes with controlled chirality and electronic properties remains a significant challenge despite some recent advances. − …”

Quantitative Determination of How Growth Conditions Affect the 3D Composition of InGaAs Nanowires

“…There is considerable interest in new-generation manufacturing technologies (MacDonald & Wicker, 2016;Wang et al, 2016;Martin et al, 2017;McHugh et al, 2017). Among various techniques, a bottom-up crystal growth paradigm for the manufacture of nanowires has been receiving extensive attention since Wagner & Ellis (1964) first proposed a metallic seed induced crystal growth method, now known as the vapor-liquid-solid (VLS) mechanism (Qu et al, 2015(Qu et al, , 2016. Subsequent efforts have been made to downsize the application of this method to allow pseudo-1D nanowire synthesis to cater to the requirement for device miniaturization for various applications.…”