Lead-supported germanium nanowire growth

Direct Synthesis of Hyperdoped Germanium Nanowires

“…The most popular synthesis approach is the use of metal growth promoters in bottom-up processes including vapor–liquid–solid (VLS), supercritical-fluid–liquid–solid (SCFLS), and solution–liquid–solid (SLS) mechanisms as well as the growth by solid metal seeds . Many metallic growth seeds have been described in the literature to result in highly crystalline Ge NWs. − For some of the above-mentioned applications doping of the NWs is a prerequisite, which can be achieved either by external sources during crystal growth − or by the incorporation of atoms from metal seeds − used for the realization of anisotropic crystal constitution. The incorporation of dopants in the Ge matrix has recently been the focus of several studies, and rather effective doping with heavy group III atoms has been observed in low-temperature growth of Ge NWs using In as seeding material and also for Bi in Ge nanoparticles .…”

A Review of Self-Seeded Germanium Nanowires: Synthesis, Growth Mechanisms and Potential Applications

“…Cd and Tl are not very suitable for Ge nanowire growth due to droplet–nanowire system surface tension, a crucial element in nanowire growth. Group III, i.e., Ga [ 114 ] and In [ 115 ], IV, i.e., Sn [ 116 ] and Pb [ 117 ] and V, i.e., Sb [ 40 ] and Bi [ 118 ], elements are much more interesting as seed materials due to their low eutectic temperatures while having potential doping capacities as both n-type and p-type dopants. Type C catalysts, e.g., Cu [ 119 ] and Ni [ 120 ], are of particular interest due to their compatibility with group IV materials, and thus, potential integration in the Complementary Metal–Oxide–Semiconductor (CMOS) industry [ 121 ].…”

Drastic Changes in Material Composition and Electrical Properties of Gallium-Seeded Germanium Nanowires

“…More specifically, different metallic growth seeds have been identified to facilitate the formation of highly crystalline Ge NWs, while the temperature window of their activity to serve as nucleation seed varies. [6][7][8] In addition to the morphological control, the implementation of these nanostructures in device architectures as well as the actual suitability of a semiconductor NW often requires a doping of the Ge crystal, which is typically achieved in situ during crystal growth. [9][10][11] In the recent past, the incorporation of dopants in the Ge host lattice has been in the focus of several studies.…”

“…Among the large variety of preparation techniques, metal-assisted bottom-up growth is the most popular approach to obtain Ge NWs with smooth side walls and tunable diameters. More specifically, different metallic growth seeds have been identified to facilitate the formation of highly crystalline Ge NWs, while the temperature window of their activity to serve as nucleation seed varies. − In addition to the morphological control, the implementation of these nanostructures in device architectures as well as the actual suitability of a semiconductor NW often requires a doping of the Ge crystal, which is typically achieved in situ during crystal growth. − In the recent past, the incorporation of dopants in the Ge host lattice has been in the focus of several studies. For instance, the effective doping of Ge nanostructures with group III atoms as p-dopants has been observed in low temperature synthesis using Ga, In, and Bi. − Especially the incorporation of a high Ga percentage in anisotropic Ge crystals via a low temperature chemical vapor deposition, thermally induced liquid-phase crystal growth and electrodeposition using Ga electrodes − were described to result in homogeneously distributed dopants that are electrically active.…”