Towards Reconfigurable Electronics: Silicidation of Top-Down Fabricated Silicon Nanowires

Abstract

We present results of our investigations on nickel silicidation of top-down fabricated silicon nanowires (SiNWs). Control over the silicidation process is important for the application of SiNWs in reconfigurable field-effect transistors. Silicidation is performed using a rapid thermal annealing process on the SiNWs fabricated by electron beam lithography and inductively-coupled plasma etching. The effects of variations in crystallographic orientations of SiNWs and different NW designs on the silicidation process are studied. Scanning electron microscopy and transmission electron microscopy are performed to study Ni diffusion, silicide phases, and silicide–silicon interfaces. Control over the silicide phase is achieved together with atomically sharp silicide–silicon interfaces. We find that {111} interfaces are predominantly formed, which are energetically most favorable according to density functional theory calculations. However, control over the silicide length remains a challenge.

Monolithic Metal–Semiconductor–Metal Heterostructures Enabling Next-Generation Germanium Nanodevices

“…To investigate the dependency of the Al-Ge exchange reaction on the crystal orientation, the Ge pattern on the (100) device layer was rotated in steps of 22.5° from the original ⟨110⟩ direction, ending up finally in a ⟨1̅10⟩-oriented Ge pattern (see Figure S5a ). In accordance with similar investigations concerning the silicide formation in top-down fabricated Si nanostructures, 30 no significant dependence of the Al-Ge exchange rate on the crystallographic orientation was found (see Figure S5b ). The ability to fabricate devices with different orientations with similar Ge channel lengths provides a significant advantage with respect to the future wafer-scale integration of Al-Ge-Al heterostructures.…”

Controlled Silicidation of Silicon Nanowires Using Flash Lamp Annealing

“…Moreover, the interface is a shared, energetically most favorable (111) plane, in accordance with the simulation results reported in our previous work. 35 Furthermore, fast Fourier transformation reveals the formation of NiSi 2 having exactly the same orientation as the interfacing silicon. It was reported in 51,56,57 that Si/NiSi interfaces result in strained Si nanowire segments or dislocations to relax this strain.…”

Conductive Materials with Elaborate Micro/Nanostructures for Bioelectronics

“…Georgiev et al presented their investigations on nickel silicidation of silicon nanowires (SiNWs) fabricated by the top-down approach. [88] Here, SiNWs were fabricated using EBL and inductively coupled plasma (ICP) etching (Figure 3b). As the silicidation process is important for the application of SiNWs in reconfigurable field-effect transistors, the employment of EBL and alternative annealing techniques with shorter annealing times makes the silicidation process more controllable.…”

“…Reproduced under the terms of the CC-BY Creative Commons Attribution 4.0 International license (http://creativecommons.org/licenses/by/4.0/). [88] Copyright 2018, The Authors, published by MDPI. c) Schematic fabrication of ZnO nanopatterns using EBL-based direct-write technique.…”

“…Resist layers as molds and conductive layers as substrates Nanowires, [88] line patterns, [89,93,106] nanogaps, [83] film [99,104,105] Electric conductivity and surface wettability E-skins and biosensors…”