Direct growth of germanium and silicon nanowires on metal films

Abstract

We describe the basic thermodynamic and kinetic aspects that govern the growth of Si and Ge nanowires directly on bulk metal films. We illustrate essential differences between the vapour-solid-solid and the conventional vapour-liquid-solid nanowire growth. Ge and Si nanowires were formed on a select set of metal films including Ag, Al, Au, Cr, Cu and Ni. Metals that form silicides or germanides (Cr, Cu, and Ni) generally yield higher quality nanowires compared to nanowires grown on metal films whose equilibrium phases are defined by alloyed phases below eutectic temperatures (Al, Ag, Au). Combinatorial experiments presented here provide new basic insights into nanowire formation in the context of metal germanide and silicide formation rates. The mechanism established from our experiments successfully predicts the nanowire growth under a broad range of conditions and also predicts the nanowire growth on other metals to provide guidance to future progress in nanowire synthesis.

Semiconductor Nanowire Light‐Emitting Diodes Grown on Metal: A Direction Toward Large‐Scale Fabrication of Nanowire Devices

“…Though direct growth of semiconductor nanowires on metals was demonstrated in several material systems, such as Si, Ge, CdS, and ZnO, it was only very recently reported by Wolz et al for GaN nanowires grown on sputtered Titanium (Ti) films . However, operating III‐Nitride nanowire devices electrically integrated and directly grown on metal were not yet demonstrated to our knowledge.…”

Diameter-Controlled Germanium Nanowires with Lamellar Twinning and Polytypes

“…[1][2][3][4][5][6][7][8] The integration of semiconductor nanowires into device geometries 9 requires control over their morphology, dimensions, growth orientation, crystal phase and structural defects. Catalytic bottom-up approaches, such as vapor-liquid-solid (VLS) [10][11][12] , vapor-solid-solid (VSS) [13][14] , supercritical fluid-liquid-solid (SFLS) [15][16][17] techniques, are popular routes for growing high-aspect ratio one-dimensional nanostructures [18][19] , where nanowire diameters can be controlled by the dimension of the catalysts. 20 Control over nanowire diameters, in turn, facilitates regulation over their growth orientation.…”

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

“…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 ]. As type B catalysts are promising due to their doping capacity, type C materials have become popular due to their promising ability to be used in microelectronic applications where properties such as high conductivity and high-quality crystal structures are required.…”